construction of distillation solvent recovery system

125
Scholars' Mine Scholars' Mine Masters Theses Student Theses and Dissertations 1960 Construction of distillation solvent recovery system Construction of distillation solvent recovery system Joseph Richard Aid III Follow this and additional works at: https://scholarsmine.mst.edu/masters_theses Part of the Chemical Engineering Commons Department: Department: Recommended Citation Recommended Citation Aid, Joseph Richard III, "Construction of distillation solvent recovery system" (1960). Masters Theses. 2673. https://scholarsmine.mst.edu/masters_theses/2673 This thesis is brought to you by Scholars' Mine, a service of the Missouri S&T Library and Learning Resources. This work is protected by U. S. Copyright Law. Unauthorized use including reproduction for redistribution requires the permission of the copyright holder. For more information, please contact [email protected].

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Page 1: Construction of distillation solvent recovery system

Scholars' Mine Scholars' Mine

Masters Theses Student Theses and Dissertations

1960

Construction of distillation solvent recovery system Construction of distillation solvent recovery system

Joseph Richard Aid III

Follow this and additional works at: https://scholarsmine.mst.edu/masters_theses

Part of the Chemical Engineering Commons

Department: Department:

Recommended Citation Recommended Citation Aid, Joseph Richard III, "Construction of distillation solvent recovery system" (1960). Masters Theses. 2673. https://scholarsmine.mst.edu/masters_theses/2673

This thesis is brought to you by Scholars' Mine, a service of the Missouri S&T Library and Learning Resources. This work is protected by U. S. Copyright Law. Unauthorized use including reproduction for redistribution requires the permission of the copyright holder. For more information, please contact [email protected].

Page 2: Construction of distillation solvent recovery system

T\1..1 o C» ' \

CONSTRUCTION OF DISTILLATION SOLVENT

RECOVERY SYSTEM

BY

JOSEPH RICHARD AID, III

A

THESIS

submitted to the faculty of the

SCHOOL OF MINES AND METALLURGY OF THE UNIVERSITY OF MISSOURI

in partial fulfillment of the work required for the

Degree of

~ .f ~\ ·, .·. .. ' ,. ' ·. , ' /

\ ' . .I

'~.~

Page 3: Construction of distillation solvent recovery system

-ii-

TABLE OF CONTENTS

TIT!Ji; PAGE ••••••••••••••••••• o ..... o........ i

TABLE OF CONTENTS ~ O e O O O o O O O O e O O o o ' o • O O e O O o O O ii

I. INTRODUCTION•••••••••••••••••••••••••••••••

II. LITERATURE REVIEW ••••••••••••••••••••• ~ •••• 4

Chemical Processing .of Nuclear ·Fuel • • • 4

Introduction •••••••••••••••••••••• 4

Nuclear Fuel Elements ·······••ooo 6

Dissolution •••o~•o••~•oo~••••••o• 8

Phase contacting, Separation, and Purification 0000000•0•••. ••••••• 10

Oxide, Hexaflu.oride, and Metal Production 000000•00••0•.•oo.~o•oo 17

Distillation •o••o••o•••••••••••••o•oo• 18

Calculations 0 0 e O e O O O e O e O O O O O O O O O e 19

Tower Hydraulics •••• o. o •••••• o o o o o 19

Control and Instrumentation

Water-Methano.l~Tr:lchloroethylene .

000000 20

System o•·~··•o••o••o••o•••o••• :•••.o••o 21

Vapor-Liq~i~ _Equilibrium •••• o . _' ••• ;:··23

Enthalpy •••••••• ·- ~ .• • o .••••••• ~ • ~ • • • 23

Density ••••••o••••••o••••~~.o•••• 23

Refractive Index · •• ~ •••••••• o o ~ ••• o 23

Gas-Liquid Partition Chromatography o•• 23

Theory o o • o o • o • o • o o •••• _o • o • o • o o • • • 28

Equipme:r:it •00000•••0•••••••••••••• 29·

Page 4: Construction of distillation solvent recovery system

III.

-111-

Gas Flow Control ••••••••o•~ 29

Column and Thermostat 31

Sample Introduction • 0 •••••• 31

Component Detection 0 • • • • • • • 32

Applications • • • 0 • • • • • • • • • • • • • • • • 32

EXPERI:MENTAL • ••••• .••••••••••••••••••• 0 •• ~. 34

Purpose of Investi§ation ••••••••••••• 34

Plan of Investigation •••••••••••••••• 34

Literature Review •••••••••••• ~ •• 35

Redesign and Purchase Specifica-tions ••••••••• · •••••••••••••••• . 35 ;.., .:

Con~truction •••••••••••••••••••• 35

Analytica~ •••••••••••••••••••••• 35

Materials•••••••••••••••••••••••••••• 36

Construction and In~tallation ot Eguipment ••••••••••••• ~ •• . •.. • • • • • • • 37

Flow Sheet, · • • • • • • • • • • • • • • • • • • • • • • 37 ·

Equipment Placement••••••••••••• 37

Tanks ........... ·• .............. . Pumps . .

•••••••••••••••• 0 •••••••• . •.

Distillatiqn Column ·• ...........• Reboiler · •••• .•••••••• ~.~ •••••• ~ ••

37

41

43

47

Condenser •••••• ·• • · •.•••••••••••••• · 47

Feed H~ater ••••••.••••••••••• ~ ••• 50

Feed Prehea ter •••••• .•••••• ·• • • • • • 50

Distillate Cooler •••••••••••••• ~ 50 .,

Instrument Panel .......... • .• .... 53

Page 5: Construction of distillation solvent recovery system

IV.

-iv-

Control Instrumentation • ·• ••••••• 53

Instrument Air

Process Piping

O O O O • O O • O O • 0 • ~ O O O O

O O O O • • 0 0 • 0 0 0 O O O O O O

58

58

Vent System 00000••••0••0~•••0••• 60

Electrical Wiring·~·!· ······••••• 60

Operational. Procedure ••••••• o·• •••• ~.. 63

. Preliminary Procedure· • • • • • • • • • • • 63

Start-up Procedure· • • • • • • • • • • • • • • 65

Continuous Operation•••••••••••• 67

Shut-down Procedure ••••• ·•• • • • • • • 68

Sample Calculations • • • • • • • • • •.• • • • • • • • 69

Determination of Flow Rates and Heat Requirements •••• o ••• o ••.•• 70

Calculation-of Distilate Product Rate and the Re-flux Rate , ••••••• o •••• o • • • 71

Calculation of the Bottoms ·Rate •••••o••••••••••••••• 73

Calculation of the Heat Re-· quirements. · • • • • • • • • • • •. • • • • 74

Calculation of the Theoretical Plates ....................... ·•.•• 75-

Results of. the· Calculations .••• · •• 76

Calibration o.f Analytical I:astruments. 76

Westphal Balance •••••• ~. o... ... . . . 79

Dipping Refractometer••••••••••• 79

Gas Chromatograph .••••••••••••••• · 79

Unknown SamP,les •••••••••••••••.• ·,; 82

DISCUSS ION ••••• o : ••••••••• . •· o ••••• o •••• ~ ••• o

Discussion of Equipment O O O O O O O O O O O o O O

Page 6: Construction of distillation solvent recovery system

v. VI.

VII.

VIII.

IX.

-v-

Distillation Column••••••••••••• 85

Reboiler •••••••••••••••••••••••• 86

Condenser ••••••••••••••••••o•••• 87

Auxiliary Heat Exchangers ••••••o 88

Feed Heater ••••••••••o••••• 88

Feed Preheater ••••••••••••• 88

Distillate Cooler ••••o••••• 88

Process Pumps o•••••••••••••••••• 89

Tanks and Taruc Rack••••••••••••• 89

Vent System••••••••••••••••••••• 90

Discussion of Instrumentation •••••••• 90

Process Instrumentation••••••••• 91

Analytical Instrumentation •• -•••• 91

Recommendations • • • • • • • • • • • • • • • • • • 0 • • •

Distillation Column ••••o••••••••

Condenser • • • • • • • • • • • • • • • • • • • • • • •

Limitations • • • • • • • • • • • • • • • • • • • • • • • • • 0

CONCLUSIONS e • e e • • • • • • • • • • e • e • e • • • e O • • • 0 e • e

92

92

93

94

96

S~~RY •••••••••••••••••••••••••••• o.. . . . . 98

APPENDICES •••••••••o~•••••••••••••••••••• 100

Appendix A, Nomenclature•••••••••••• 101

BIBLIOGRAPHY ••••••••o•••••••••••••••••••• 102

ACKNOWLEDGEMENTS • • • • • • • • • • • • • • • • • • • • 0 • • • • 113

X. VITA •••••o••••••••••••••••••••••••••••••• 115

Page 7: Construction of distillation solvent recovery system

Figure 1.

Figure 2o

Figure 3.

. .

Figure 4.

Fig~re 5o

Figure 60

Figure 7.

Figure 80

Figure 9.

Figure 10.

Figure 11.

Figure 12.

Figure 13.

-Figure 14.

Figure 15.

-vi-

LIST OF. FIGURES ·

Block·Diagram Representing the Reactor Fuel Cycle with ·Sol-vent. Extraction Reprocessing ••• . 11

Block Diagram Representing the Reactor Fuel Cycle withrFlu~ oride Volatility Reprocessing · •• 12

Block Diagram Representing the Reactor Fuel Cycle with Pyro­metallurgical Reprocessing ...... 13

Generalized ~olvent -Extraction Flow Sheet • • • • • • • • • • • • • • • • • • • • •. 1 5

.. Enthalpy Composition Chart for

Methanol-Water Solutions at 1 Atmosphere ••••••••••••••••o•• 25

Schematic Diagram of Gas Chro­matography Apparatus -... o o ••••• o 30

Distillation Flow Sheet ~···•o•••·•• 38

The Distillation:· Unit showin·g the Distillation Column, the Control Valves, and the T.ank ,Farm •••••• 39

The · Distillation · Unit -showing;. the Bottom ·or the Column and the Re boiler • o·• ·• ••••••••••••.•• o.... 40

Rear View of· Tank Farm.and Tank. · Rack • • • • • • • • • ~ .• · • • • • • • . • . • • • • • • •• o 4 2

Process Pumps and Control Vailives. 44

The Distillation Column •••• o ••••• . 45

Distillation Column Installation Det_ails ·. 9 9·•· • .•••.••••••• .-; • .• ~ • • • .• • • 46

View of the Reboiler. from the South Side·· of · the Unit o •••••••• 48

View of the Reboiler from the · North Side· of the Unit •• ~ ••.••• ." 49 ·

Page 8: Construction of distillation solvent recovery system

Figure 16.

Figure 17.

Figure' 18.

Figure 19.

Figure 20.

Figure 21 •

Figure 22 .•

Figure 23.

Figure 24.

Figure 25.

Figure 26.

Figure 27.

Figure 28 •.

-vii-

The Product Condenser •••••••••••• 51

The Feed Heater •••••••••o•••••••• 52

. Front View of · the Instrument -Panel .-•••• · •••••• .•••.•••••• .•• ~ • • • 54

Rear View of the Instrument ~anel showing the ·Tel-0-Set Instru­ments., the Instrument Air Header, and the Electrical Wiring••••••••••••••••••••••••• ·55

Process Control Flow Diagram ••••• 56

Location and Numbering of Thermo-couple Leads •••••••••••••••• . • •• . 57

The Instrument Air Compressor •••• 59 . .

Vent System Flow Diagram·~······· 61

Wiririg Schematic••••••••••••••••• 62

Ponchon-Savarit Solution to· the Sample Calculations . • • • •.• • • • • • • • 72

Specific Gravity as a Function of Composition for the System . . . Methanol-Water at 25 oc •••••••• 80

Refractive Index as a Function of Composition for the S~stem . · ·Methanol-Water at 25 C • • • • •. • • • ~.1

Ratio of Areas of Methanol-Water Peaks as a Function of Compo- · si tion by Gas .. Chromatography·· -~ .o ~ 83

Page 9: Construction of distillation solvent recovery system

TABLE I.

TABLE II.

TABLE III.

TABLE IV.

TABLE V.

TABLE VI.

TABLE VII.

-viii-

LIST OF TABLES

Current Atomic .Energy Commission . . Assignment. of Fuel Processing

Responsibility by Fuel Types ••• 7

Table of Solvent ·Properties o o . : ••• 22

Vapor-Liquid Equilibrium Data for Methanol-Water at ·760 milli- · meters of _Mercury •o•••••••••••• 24

Density, Specific Gravity, and Composition Relationship of Mix­tures of Methanol and Water at 25 °c .•••• 0 ••• .••• 0 •• · - •• .•••• 0 ~ 0 • 26

Refractive Index of· Mixtures of Methanol and Water at 25 oc . •• .•• 27

Effect of Reflux Ratio on the Theoretical Plates Required for Separation ••••••• · ••••••••• o •••• ·_ 77

Results of Theoretical Material and Energy Balances •••••.•• -••.• ·• • 78

TABLE VIII.· Analysis of Unknown Samples of Methanol-Water Mixtures as Per Cent Methanol •••• o.o ••••••••.•• -•• 84

TABLE IX. Limitations of Equipment • • • • • • • • .• 95

Page 10: Construction of distillation solvent recovery system

I. INTRODUCTION

When a nuclear fuel is uburnt 11 in an atomic

reactor it is not possible to completely utilize the

fissionable material present due to build-up of fission

products (which act as poisons), depletion of the fis­

sionable material, and radiation damage to the fuel

elementao .Chemical processing of nuclear fuels is con-. .

earned with the recovery of the ·fissionable materials,

specif~cally uran1um,.pluton1um, and thorium, from the

spent fuel · elementao There are t\·10 general _metp.oda of

reprocessing nuclear f~~ls: aqueous and non-aqueouso·

The aqueo~~ methods· include solvent extraction, ion

exchange, and precipitationo Comprising the non-aqueous

methods are_fluoride volatility and pyrometallurgyo At

the present time only the aqueous method is. ·being· used

on a commercial a~ale by the Atomic Energy Comm1J:3Sion

in its reprocessing plants at O~k Ridge, tdaho Falls,

Savannah River, and Hanfor.do . .

Of the aqueous pro.ceases fo.r uranium purifi!)ation,

the most .comm.on is the 1/iq-µid-liqui~ extracti.on of ·Uranyl

nitrate, ~y m~ans or'~ organic soivent, ·from-a urany·~ ­

nitrate-fission products solutiono The uranyl nitrate · ..

is then re-extracted from the organic phase by 1.·1ater and

· is further processed- to the uranium oxides, uranium

Page 11: Construction of distillation solvent recovery system

-2-

tetrafluor~de, and finally to the uranium metal. If an

enriched uranium is wanted, the tetrafluoride is conver­

ted to the hexafluoride which is processed by gaseous

diffusion.

It is desirable .that students in chemical and

nuclear engineering have a sound theoretical and prac­

tical background in the chemistry and chemi-cal engineer­

ing involved in the aqueous process. 'ro support instruc·­

tion in this field, a model of an aqueous nuclear fuels

reprocessing plant was designed and constructed in. the

Unit Operations Labo~atory of ·the University of Missouri

School of Mines and Metallurgyo Since safety considera­

tions ruled out the use of radioactive materials and/or

heavy metals, the system water-.methanol-trichloroethylene

was chosen to represent the uranyl nitrate-organic solvent

system employed in the actual process. In this case,

methanol, representing the uranium, would be extracted

from a solution of methanol-trichloroethylene by water,

representing the organic solvent. The resulting mixture

of methanol and water then would be separated by frac­

tional distillation, representing the re-extraction._: and

further purification stepso

The purpose of· this investigation was to construct

the neceisary equipment to isolate, by fractional dis- ·

tillation {separation by differential vapor pressure),

the products of a liquid~liquicl extraction {separation

Page 12: Construction of distillation solvent recovery system

-3-

by differen:tial solubility) unito The construction

of the distillation unit was an integral part of and

coordinated with the construction of the extraction -:

equipment.

Page 13: Construction of distillation solvent recovery system

-4-

II. LITERATURE REVIEW

The background material for this investigation

was considered from four points of view: (1) chemical

processing of nuclear fue~s, (2) · distillation,

(3) water-methanol-trichloroethylene system, and

(4) gas-liquid partition chromatography.

· · Chemical Processing of Nuclear Fue°ls

There has been a great deal of research and de­

velopment work in the field of chemical processing of

nuclear fuels. This review ·1s concerned chie.fly with

the presentation of a broad basic background of the field.

Introduction. At the pre~ent time, the only prac­

tical method of utilizing ·nuqlear power involves the gen­

eration of.heat by nuclear fission(~ 1). In turn, the

heat is employed to produce steam from water. The steam

is then further used to drive a turbine in the production

of electric current. Thus~·the nuclear reactQr is actu­

ally used only to replace the.boiler in the conventional

power s~ation, commonly referred to as the fossil fuel

power station~. The fossil fuels are petroleum gas, oil,

and coal.

· A major difference between burning fossil.and

nuclear fuels is the "combustion products. 11 When fossil

Page 14: Construction of distillation solvent recovery system

-5-

fuels are burned, combustion is virtually complete; and

the ash is ready for immediate disposalo However, in

the case of the nuclear reactor, the fuel is not complete­

ly utilized; and the "unburnt" fuel is usually too valua­

ble to be wasted and too dangerous for disposai by ordin­

ary means( 11,s1).

Chemical processing is concerned with the decon­

tamination and recovery of fissionable materials from

the irradiated fuel elementso Many different.methods

have been proposed :for the processing of irradiated nu­

clear. fuels; but they can be divided into two main clas-

sifications: aqueous and non-aqueouso The aqueous

methods basically involve liquid-liquid<.extraction;

however, seine work has been done .with ion exchange and

precipitation { 21 ' 69 ) o The. non-aqueous methods include

pyrometallurgy and fluoride volatilit/ 17 ' 44,.77 ). . The

major portion of the . reprocessing -done in the .United

States is by liquid-liquid .extr~c~ion< 66 ).

It is difficult to pr~dict f _uture trends .in the

chemical processing of nuclear fuels • . Of the processing

methods now in use, it appears that the developments

must come in the technology rather than in the chemistry -·

in order to make ~rem economic~lly feasible. The demand , .

will be for · substantial·,.reduction in fuel processing

cqsts and for closer integration of processing plant

and operating reactor( 55 )0

Page 15: Construction of distillation solvent recovery system

-6-

With this brief introduction it is the intent to

present _information on the essential aspects of chemical

processing of nuclear fuelso The following four principal

related topics are now presented: (1) different types of

nuclear fuel elements and ·the factors involved in their

design; (2) . dissolution of irradiated nuclear fuels to

convert them to a form suitable for further processing;

(3) separation, recovery, and purification of the fis- ·

. sionable materials from the fission products; - and (4)

preparation of the metal oxides, . tetrafluoride, an_d pure

metal from the product of the purification stepo

Nuclear Fuel Elementso A wide range of nuclear (32,53)

fuel types is possible • Some of the potential ( 38)

fuels include uranium metal . and its alloys with such ' (74) - -

metals as aluminum , chromium,. niobium, molybdenum, · ( 37)

and zirconium. Uranium dioxide _ and other. refrac-. - . { 42)

tory compounds of uranium are the basis for ceramic

and cermet fuelso Thorium {_a 4) . and plutonium ( 52 ) are

also used as fertile and fissionable materialso · Clad-

ding materials for the various fuels might be -aluminum, . - . . ~ · ( 68)

stainless steel, zirconium, or_ Zircaloy o The clad-

ding, or jacket, can. be metallurgically bonded to the

fuel; or a liquid-metal thermal bond_ with sodium may be

usedo The enrichment of the uranium used is also quite

important in determining the ··make-up of the fuel elemento

A summary of the various types of fuel elements currently

being processed is given in Table I.

Page 16: Construction of distillation solvent recovery system

-7-

TABLE I

Current Atomic Ener5y Commission Assi5nment of Fuel Processin5

Responsibility by Fuel Typesa

Idaho

U-Zr(Zr)-HF

U02-SS(SS)-H2S04

U-~l .(Al)-HN03

Handford

·U02(Zr)-NH4F

. U02 (SS) -H2 SO 4

_TIO(Al)-HN03

· ·u(Al)-HNo3

Oak Ridge

U-Mo(SS)-H2S04b . b .U02(SS)-H2S04

Th02-U02(SS)-H2S04b

U-Al(Al)-HN03

·· u-zr ( Zy )-~H4F

Savannah River

U-Mo(Zr)-HF

U(Al)-HN03

aThe ~ignificant dissolution agent is shown after each fuel type. The .core of the fuel element· is shown before the parenthesis and the cladding· is within the parenthesis. (SS-stainless.steel, Zy-zircalloy)

_bDarex alternate, decladding if sodium_bond~d.

-Baranowski, F-. P. : Scope ·or the ~ower: Fuel ;Broces·sing Program, "Pro- . · ceedin§s of ~h~- AEC · Symposium for Chemical Processing of Irradiated :: ·_ · Fuels, ·held· at Richl~nd ,- Washington, October 20 and 21 , 1959, p. 14.

Office of Technical Services, Department of Commerce, Washington 25, D • C • ," 1 960 •

Page 17: Construction of distillation solvent recovery system

-8-

An interesting review of the factors involved

in the design of reactor fuel elements appeared in the

literature recently< 76 ) o The factors included: {1)

nuclear physics, (2) reaction rate, {3) temperature,

and (4) heat transfero The primary design, which is

concerned with the reaction rate, the temperature de­

sired, and the approximate shape and arrangement of the

fuel elements, is dictated principally by nuclear physic.so

After these restrictions have been decided upon, heat

transfer becomes quite important since there is the pos­

sibility of the mill~on-degree temperature· of an uncon­

trolled chain reactiono In a nuclear reactor the prob­

lem is not the generation of heat, but its effective.re-

moval and utilizationo

Fuel elements as they are known today may become

obsolete in the future with the arrival of the homogene­

ous reactor{g) o Instead of the fuel and moderator being

engineered separately, as is the case in the heterogene­

ous reactor, they are intimately mixed in the homogeneous

reactoro Several homogeneous reactors have been built

for experimental purposes< 33) o One advantage of the

homogeneous reactor is that a aide stream of the fuel can

be continuously withdrawn for reprocessingo

Dissolutiono Dissolution is the process whereby

the heterogeneous reactor fue'l elements are converted

from solid fuel to liqu14 feed solution for reproceaaingo

Page 18: Construction of distillation solvent recovery system

-9-

The actual material used for the dissolution is deter-

mined by the particular type of fuel element to be re­

procesaed(7) o The composition of the fuel can vary

widely, along with the ·possibility of many different

cladding, or jacketing,_ materialso In general, however,

nitric acid dissolution is used for uranium, urani'l.:Ull­

aluminum alloys, and thoriumo Sodium hydroxide is used

for dissolution of aluminum jackets and uranium-aluminum

allojs; and fuel elements containing zirconium can be

dissolved in hydrofluoric acid or in solutions of ammo-

nium fluoride, singly or in mixture with ammonium nitrate( 85)o

During the dissolution, gaseous fission products are

often liberated and must be disposed ofo Also, quite fre­

quently, oxides of nitrogen will be liberated; and these

may have to be removed from the effluent gas by scrubbing

with caustic(S)o

In some.cases it may be desirable to remove the

cladding before making the final product dissolution:

for example, if the cladding is not soluble in nitric

acid whereas the fuel is, or if the fuel requ~res a less

corrosive disso;J_ving agent than does the jacket(SB)o The

cladding may be removed by either mechanical or chemical

meanso The mechanical methods include sawing, shearing,

and pulverizing. The chemical methods are similar to

those used for the fuel dissolutiono

Page 19: Construction of distillation solvent recovery system

-10-

Batch dissolution .is satisfactory in most appli-

cations; however, continuous dissolution methods are

being studied< 54)0 Besides the obvious reasons in fa­

vor of continuous dissolution, such as greater through~

put in smaller pieces of equipment and more uniform

product control, there is the criticality problem< 54 )0

In a system containing fissile material certain combi­

nations of concentration and vessel geometry may result

in an accumulation of sufficient mass of the fissile

material to allow a chain reaction to progress { 14, .57) o

If continuous dissolution is employed, the vessel size

for~ given through-put will be smaller; a~d c~oser con­

trol can be maintained over the concentrationar fissile

material.

Phase Contacting. Separation, and Purification.

Recovery a~d purification methods have been divided into

two main classes: aqueous and non-aqueouso The first

is characterized by the use of aqueous solutions for

reprocessing of the irradiated nuclear fuelso The non­

aqueous methods include fluoride volat_ility and pyro­

metallurgical processing.

The over-all react.or fuel cycles for the various . ( 45)

processi_ng methods are quite different o . The cycles

are shown a.ahematically in Figures 1, 2, and 3 for the

s~lvent extraction, fluoride. volatility, and pyrometal­

lurgical processes. It is n~ted that the method employed

Page 20: Construction of distillation solvent recovery system

REACTOR COOLING

FABRICATION

REDUCTION HYDRO-

TO METAL FLUORINATION

REDUCT~ON GASEOUS {TO U~) DIFFUSION .

-11-

DlSSOLUT ION

REDUCTION

' ' '

FLUORIN·ATION

FIGURE 1.

HEAD END SOLVENT

EXTRACT I ON

SOLVENT

EXTRACTION

DE NITRATION

BLOCK DIAGRAM REPRESENTING THE REAC,:OR FUEL CYCLE WITH SOLVENT EXTRACTION

REPROCESSING

La:wroski, So: Non-Aqueoua Processi:gg - An Introduction, "Symposium on the Reprocessing of Irradiated Fuels, 11 Po· 4800 Technical In.formation Service Extension, Oa~ Ridge, Tenno, 19576

Page 21: Construction of distillation solvent recovery system

REACTOR

FABRICATION

COOLING

REDUCTION

TO METAL

-12-

DISSOLUTION

AND

FLUOR I NATION

REDUCTION

(TO UF4)

FIGURE 2.

FRACTIONAL

DISTILLATION

GASEOUS

DIFFUSION

BLOCK DIAGRAM REPRESENTING THE REACTOR FUEL CYCLE WITH FLUORIDE VOLATILITY

REPROCESSING

La.wroski, a.: N·on-aqueous Processi~ - An Introduction, "Symposium on the Reprocessing or Irradiated Fuels," p. 482. Technical Information Service Extension, Oak Ridge, Tenn., 1957,

Page 22: Construction of distillation solvent recovery system

-13-

MOLTEN REACTOR

REACTOR -- DE CLADDING - MAGNESIUM ~ BLANKET ~

EXTRACTION

H REACTOR

CORE

y REMOTE

FUEL -- OXIDE ~

FABRICATION d~ DROSStNG

~ 1

FIGURE 3.

BLOCK DIAGRAM REPRESENTl'NG THE REACTOR FUEL CYCLE WITH PYROMETALLURGICAL

REPROCESSING

-,.....-- (EXCESS

PRODUCT)

Lawroski, s.: Non-aqueous Processin~: - An Introduction, -"symposium on the . Reprocessing of Irradiated Fuels, p. 482. Technical Information Service

Extension, Oak Ridge, Tenn., 1957 •.

Page 23: Construction of distillation solvent recovery system

-14-

. for fuel recovery in the ,solvent extraction process is ..

. comparatively. complicated~ Many operations must -still

.be performed arter the chemical" purification step be:- ·

fore the recovered fuel can be re-introduced to the

nuclear reactoro An examination of the flow sheet for

the fluoride volatility method reveals that a lesser

number of operatingsteps is required for the reactor

-f~el cycleo A still further simplification of the fuel

cycle may·be obtained with a pyrometallurgical type of

processo

.. For the present at least, solvent extraction is .

the· most versa.tile method for complete decontamination

of plutonium, . thorium, and uranium fuels from fission ·

products and other contaminants. Descriptions of the

two major processes (Redox and Purex), as well as des­

crip·tions ~f the _ solvent-extraction processes. mo~1f1ed

· to handle enriched ·ruels and fuels -containing .various · .-:' •-- •· · · · · ·· . .. · . ··. -· (11,1a·,7a,a6) _alloy.ing agents, have_ been publishe~ · · .. ~ A

A generalized solvent~extrac~ion flow sheet is shown . . .

· .inFigur~· 4 ·and is typical . f~r th(:f Red.ox pro~ess, which · . . . . ' . ' . . '. . .

· 1~ .· characte~ized .• by the use . of h~xone · (Diethyl isobutyl .< ket~~e)as ihe • sol Vento it could also al)pljr to the · . ..

Pur~x pr_ocess, which . uses . tributyl. phosphat~ '. diluted ..

· ·.· w~ tl'l. ~ydroc~rbon diluent for t}?.e s.olvento . · .· .. .. ·

Page 24: Construction of distillation solvent recovery system

OFF

GAS

DISSOLUTION OF

IRRADIATED URANIUM

IN HN03

ORGANIC EXTRACTION

ACTIVE

WASTE

STORAGE

NITRATE. SCRUB AND

SALTING AGENT

E x T R A c T I

0 N

-15-

DILUtE ACID

... REDUCING DILUTE

AGENT ACID

USED SOLVENT TO RECOVERY

p s A T R R T I I p T p

ADDITIONAL I I SOLVENT 0 N EVAP.

EXTRACTION N G CYCLES. I N G

.ORGANIC EXTRACTION

----- EVAP. t----c>ADDITIONAL SOLVENT EXTRACTION CYCLES

FIGURE 4.

GENERALIZE~::., SOLVENT-EXTRACTION FLOW SHEET

u. s. Atomic Energy Commission: Reactor Fuel frocessing, 1, No. 1, 7 (1958).

Page 25: Construction of distillation solvent recovery system

-16- .

The- fluoride volatility processes comprise ··a

group o·f non-aqueo~s reprocessing methods which exploit

the volatility of uranium and plutonium hexafluorides (12,78,86) · ·- . . . .

o Except for tellurium ( and molybdenum which_

is~ fission product -with a short.ha1:r:..11re), all of

the fission products form fluorides which are much.less

volatile than uranium hexafluorideo Uranium hexafluoride

and plutonium he~afluorid~ have nearly the same volatili­

ties. However, it is difficult to fluorinate· p~utonium -

to the hexafluorid~; and the lower fluorides.of plutonium ..

are not volatileo Thus, the relative ease of fluorination ·.

of u~anium .and plutonium .. may be used for t1:1,ei~ separ~tion~· · .

The mos"t;t.important of the fluoride volatility methods are: ·

( 1) fused· salt processes, ( 2) ·continuous. dissolution

by inter-halogens, . and ( 3) a combination ·of aqueous

dissolutio;n. with fluorination and fluidization techniqueso

~he.major difficulties encountered a.re with techniques

and materials of -construction ·in the feed dissolution

stepo .. .

The.· pyrome.tallurgica.l proces_se~ have ah inherent

compactness wh.ichresults from avoiding chemical Qonver­

sions dUI'ing th~- proces;ing . steps( 13,7i3,B6) 0 ·. .

' ·, . · , : .: :

the ·fuel ·· is ·retained.· in the ·metallic 'state . througho'Ut·;

howeyer, proces~~s i:n w~ich _the metallic state is lost

momeii.tar1iy . or -. -in .. whi cli it11e . 'inetai(t s ·conver.t 'ea into . the ·.- .•

salt in one •step and back in the ~exi ;r:e allio inci\lcie~{

Page 26: Construction of distillation solvent recovery system

-17-

·pyrometallurgical processes are characterized by high

temperatures and low decontamination factorso It is

believed that moderate decontamination will be suffi-

cient for fuels in power reactorso The pyrometallurgi­

cal processes include:- ( 1) oxide dressing, also known

as oxide slagging or meld refining; (2) solvent·ex­

traction, either with immiscible molten metals or fused

salts; and (3) methods such as zone refining, fractional

crystall1.zation, electrolytic refining, and fractional

distillationo

Ox1de 0 Hexafluoride 0 and Metal Productiono Fol­

lowing the separation and purification steps in the re­

processing scheme, the fuel must be converted to a re­

usable form as a nuclear fuel(B 6)o The forms in which

uranium is used as a fuel are uranium dioxide, uranium

metal, and metal alloyso The product of the. aqueous

sol vent extraction process is usu_ally a uranyl nitrate

solution. The nitrate solution is denitrated to uranium

trioxide which is then reduced to uranium dioxideo The

uranium dioxide may be the desired fuel product, or it

may be fluorinated to uranium tetrafluoride from which

either uranium hexafluoride (for re-enrichment-) or ura 0

nium metal is produeedo In the fluoride vo_latility

processes, uranium hexafluoride is obtained directly

and is re-enriched by gaseous diffusion and/or is reduced

to uranium tetrafluoride for further processing to uranium

metalo

Page 27: Construction of distillation solvent recovery system

-18-

One of the important techniques receiving exten­

sive attention is the fluidized bed( 86)o Fluidized bed

reactors are used for denitration and reduction of uranyl

nitrate to the oxides and for fluorination of the oxides

to the tetrafluoride and hexafluoride.

Distillation

"Now I am come to the arts and I

shall begin from distillation, an invention

of later times, a wonderful thing to be

praised beyorid the power of men; not that

which vulgar and unskilled men use, for

they do but corrupt and destroy what is

good; but that which is done by skillful

artistSoooLet one that loves learning and

to search nature's secrets, enter upon this;

for a dull fellow will never attain to this

art of distilling."

Forta, 15890

The purpose of this section of.the literature

review is to provide information on recent advances in

the field of distillation to in.elude: { 1) calculations,

(2) tower hydraulics, and (3) control and instrumen­

tationo A basic knowledge (as covered in the standard · ,

texts) of the theory and terminology of distillation is

assumed and will not be covered( 10, 56170 , 79 ).

Page 28: Construction of distillation solvent recovery system

-19-

Calculations. The emphasis of distillation cal-

culations has changed in recent years from empirical

correlations to rigorous calculations. Not that the

principles have changed, but with the use of analog and

digital computers the simplifying assumptions formerly

made are no longer necessary.. Computers are being used

successfully for (1) prediction of vapor-liquid equi­

librium data< 15 ), (2) simulation of column behavior ( 42)

under varying conditions , (3) prediction of opti-

mum column design(l,75 >, (4) solution of multic9mpo­

nent . distillation problems ( 25 , 28 , 48 ), an·d (5) many

oth~r types of distillation problems(31 , 49,72, 83). A

committee has been established by the American Institute

of Chemical Engineers for the .interchange of computer

programs.

Other work· on distillation calculations has been

concentrated on modification of existing methods and

development of short cuts ·for the solution of equations.

The McCabe-Theile method has received considerable atten­

tion, with the emphasis on developing methods for reduc­

ing the inherent error of assuming constant vapor-liquid

ratio throughout the co1umn< 82).

Tower Hydraulics. An investigation of the tray

efficiencies of distillation columns was recently com­

pl~ted at the Universities ·of Delaware and Michigan and

the North Carolina State College. The research committee

Page 29: Construction of distillation solvent recovery system

-20-

of the American Institute of Chemical Engineers spon-.

sored the investigation and published the results in a

comprehensive booklet(S). Recent research has also in­

creased our knowledge and understanding of: (1) the·

influence of surface phenomena and entrainment on tr~y

.. efficiencies ( 89), ( 2) mass .transfer between liquids· (36) .

and vapors in bubble-cap columns , and (3) pressure . (80)

drop through bubble-cap and packed columns •

New tray designs for use in distillation columns

have been proposed. The claims in favor of the new de-

signs .are lower initial cost and higher efficiency than

the.conventional bubble-cap tray. In general these trays

operate very well at the design specifications, but. they

lack the stability of operation which is inherent in the

bubble-cap tray.

Control and Instrumentation. Progress in control

and instrumentation of distillation columns ~as been very

rapid during the past few·years, and many instruments

which were merely laboratory. curiosities five rears ago

are today helping to control chemical processes.

Through the use of improved instrumentation, the

delay between measurement of the process variables .and

applic~tion of control to the process has ~een decreased.

Of particular importance is the use of in-line analy~ical . . ( 22)

instruments: for example, 'vapor phase chromatography o

Page 30: Construction of distillation solvent recovery system

-21-

Of especial interest today is the use of compu­

ters. The possible steps in the integration of computers

into process control are: (1) use of digital data log­

gers, (2) 11on-linett calculation of operating gui~e~,

(3) computer supervi~ion of processes, and (4) dynamic

· control of processes ( 27).

Water-Methanol-Triohloroethylene System

The system water-methanol-trichlo~oethylene has

been specified for use in the operation of the unit.

Originally, the system water-acetone-carbon tetrachloride

had-been considered( 25 ' 64); but owing to safety consider­

ations, principally flash points and toxicity, this sys­

tem was abandoned. A summary of the solvent properties

for the two systems is given in Table II.

The solubility of trichloroethylene in water is . 0

0.11 per cent at 20 C, and in a mixture of methanol and

water at the same temperature the solubility of trichloro­

ethylene is only about one per cent when the concentration

of methanol is 37 per cen~( 59 , 73 >. The product.of the

extraction unit will be the feed for the distillation

unit and will contain from 15 to 20 per cent methano1( 6o).

The amount of trichloroethylene dissolved in the feed

stream to the distillation unit is subsequently assumed

as negligible, and this portion of the literature review

Page 31: Construction of distillation solvent recovery system

1 •

2.

3.

4.

TABLE II

Table of Solvent Properties

Name and· Synonyms Boiling Flash Fire Explosive Limits, Threshold % by Volume in Air Point, .Point, Hazard

OF OF Group,

Acetone 133 0 4 dimethyl ketone 2-propanone

Carbon Tetrachloride 171 * 0 tetrachloromethane

-Methanol 148 54 4 methyl alcohol wood alcohol

Trichloroethylene 189 * 0 eth1nyl trichlor1de e

(A) e

* LEL ·

American Conference of Industrial-Hygienists Can be vio1e·n·t1y decomposed· by aluminum fines Non-flammable Lower explosive limit Upper explosive limit

LEL

3.0

7.3

UEL ppm Parts of vapor per million parts of air, PY volume

Limit UEL Values,

ppm

1 1 1000

25

36 200

200

Fire Hazard Rating Fla.sh Points Non-flammable Above 140 °F 100 - 140 OF 73 ·- 100 °F Less than '73 °F

(A~

(A)

(A)

(A)

Group 0 1 2 3 4

"Handbook of Organic Industrial Solvents," pp. 25, 34, 51, 60. National Association of Mutual Casualty Companies, Chicago, Ill.

Page 32: Construction of distillation solvent recovery system

.-23-

is concerned chiefly wit~ the physical properties· of .the

me~hanol-wa.te:I' system •

. The following· .·_data. on the· me.~hanol-water system;

·were used for all calculations' and calibrations.

Vapor-Liguid .. Eguilibrium •. The vapor-liquid equi.; • ( : j •

librium data are.given in ~able III for a pressure of 760

millimeters of mercury( 2o.>. Enthalpy. The relationship bet.ween .th~ liquid

and vapor _enthalpies as a function of composition is shown·

in Figure 5~4

~. ·

.. ·. Density. · V~lues_ of density as a function of. com­

p6alt1on at ae~er!!.1 temperatures are given 1:q Table IV(i 6>, Refractive Index. Values of .. the refraotive .. index

·for the methanol~water system at several different tem­

peratures are giveri in Table vC34).

't}as-Liquid Partition Chromatography .

Initial operational procedure for the analysis

of a product by gas-liqu~d·chromatography ;s the intro­

duction of a· measured sample into· a· ·controlled·-gas stream . • / .

The. gas' .. stream then· ·acts. as ·a. carrier :for the sample as

it transports· it _t};lrotigh a heated colµmn packed with -a· ..

partitioning agent. The partitioning agent, which must··

be esae·ntially ·non-volatile at the temperature· and pres­

sure or·· oper_at1on:, is usually·. ·coated on: inert. granul_ar

Page 33: Construction of distillation solvent recovery system

-24-

TABLE III

Vapor-Liquid Equilibrium Data for Methanol-Water

at 760 millimeters of Mercury

Methanol Methanol Temperature in Liquid, in Vapor,

mole J{, mole% OC

3.21 19.0 95.3

3.72 22.2 Q4.0

5.23 29.4 92.5

5.95 30.8- 91.5

7.50 35.2 89.9

8.76 39.0 88.1

15.4 49.0 85 .1

15.8 51.6 83.9

18.2 55.2 82.9

22.5 59.3 82 .1

29.0 64.3 78.7

34.9 70.3 76· •. 7

81 .3 91 -.8 67.4

91 .8 96.3 65.6

Chu, J. C., S. L. Wang, S. L. Levi and R. Paul: "Vapor-Liquid Equilibrium Data, 1 p. 420. J. w. Edwards,Inc., Ann Arbor, Mich., 1956.

Page 34: Construction of distillation solvent recovery system

c.> 0 E D

,.: <'l)

0.

:j +-' dl

:2 :::, O'

-0

~ .Q. <U .c

+> c w

-25-

24200

21,800

21,400

21,000

20,600

20,200

1°9,800

sql 19,400 v,...c:1 t~

(/ J..-q 19,000 t:>o,...

18,600

18~200

17,800

17,400

Saturated 11. Uid ·

800 --400

0 0 0.1 0.2 o.3 0.4 ··o.5 o .6 o.7 o.e o.9 1.0 ·

Mole fraction niethan of FIGURE 5. ENTHALPY COMPOSITION CHART FOR METHANOL-WATER

. SOLUTIONS. AT 1 ATMOSPHERE

Ansell, L. s., H. Sammuels and w. c. Frishe; Enthalpy Concentration Chart for Methanol-Water Solutions, Chem. · Eng., 512., No. 4, 133 (1951);

~

0 E .ci

t.: c,) a.·

:J +-' co L~ 0 a. cu > -0

~ a. l'v .c ....... c

LLI

Page 35: Construction of distillation solvent recovery system

-26-

TABLE IV

Density, ·specific Gravity, and Composition R~lationship

of Mixture·s . of . Methanol and 'Water at 25 °c

Methanol, Methanol, · Density, . Specific . Gravity, __ ·

wt% vol .·% 25°/4° a : 25~/25° a' '

0 o.oo 0.99708 1 .0000 . 5 6.28 o.9887 0.9916

10 12.46 0.9804 0.9833 15 18.55 0 .,9726 0.9754 20 24.53 0:-96~9 0.9677 25 30.42 0.9572 0~9600 30 · 36.20 0.9492 ·0.9520, 35 41 .84 0.9405 0.9433 ·40 ·· 47 .37 0.9316 0.9343 45 52.74 o·.9220 0.9247. · ..

· 50 57.98 Ol9122 0.9.149 55 63.05 0.9019 O .9045 ,' · 60 · 67 .96 0 .·8910 0·~8936 65 72 .64' 0.8792 0.8818 70 77 .19 o.8675 0 .8790 . 75 81 .54 o.8553 0.8578 80 85.66 o.8424 o.8449 85 89 .·60' 0.8293 0 .8317 90 93.33 o.8l58 0.8182

.95 96.79 ·o .801-5 0.8038 100 100.00 'O ;7867 . _0.7890

Carr, C., and J. A. Riddick: :,Phy.sical Properties of Methanol Water System, !):_ijg.. Eng. Chem., i2,, .693 (1951).

Page 36: Construction of distillation solvent recovery system

-27-

TABLE V

Refractive Index of Mixtures of Methanol

and Water at 25 °c

Methanol Nn25

mole%

o.oo 1 .33232

21 .70 1 .33823

37.66 1 .34090

52.22 1.34163

54.23 1.34163

64.35 1 .34065

68.20 1 • 33984

80.44 1.33663

86.27 1.33505

92.48 1.33193

100 .oo 1.32773

Maximum Nn25 = 1.34170 at . 53 mole % Meth_anol

International Critical Tables, VI, p. 66. McGraw-Hill Book Co., Inc., New York, N. Y., 1929.

Page 37: Construction of distillation solvent recovery system

-28-

materials in amounts up to 40 per cent by weight·.. By

selection of the proper partitioning agent, the sample

may be separated into fractions consisting of pure com­

pounds. The pure compounds arrive separately at the

exit of the column, w~ere they are measured by a suitable

'detector. Recordings obtained by measuring the d~tector

output result in a series of peaks, whose locations pro­

vide qualitative information and whose. heights or areas

determine the quantitative analysis.

The possibility of gas-liquid chromatography was

first suggested by Martin and Synge(SO) in their paper

on liquid-liquid chromatography in 1941, for which they

received the Nobel Prize in 1952. The suggestion was

neglected until 1951, when Martin, together with James, ( 35)

proceeded to elaborate on it • Since then the tech-

nique of gas-liquid chromatography has been developed

into a powerful tool for analyzing volatile materials.

Theoryo As in distillation, a gas-liquid chroma­

tographic column can be considered from the viewpoint of

containing a number of theo.retical plates ( 39_, 61 ) • The

separation per plate and the number of plates then deter­

mine the over-all separation obtained in any one column.

The mechanism of separation is based on the varying

absorbability of the components of the sample in a non­

volatile liquid impregnated: on an inert support·. Sepa­

ration then takes place because the molecules of one

Page 38: Construction of distillation solvent recovery system

-29-

component spend more time in the carrier gas than those

of another, thus determining the residence time for each

component in the ~01umn< 43 ). Therefore, the · separation

obtained is a matter of the relative volatility, whic~

in turn is affected by the vapor pressure, adsorption

· and solute-solvent effects, and in some cases mol~cular

\'Teight of the sample components.

Equipment. The apparatus used in gas-liquid

chromatography can be divided into four categories(40):

(1) equipment for providing a controlled flow of carrier

gas, (2) the column and its thermostat; (3) the sys­

tem employed for introducing the sample, and (4) the

apparatus used for detecting the components in the ef-

fluent. These four categories are discussed separately.

A generalized flow diagram for~ gas-liquid chromatograph

is shown in Figure 6.

Gas Flow Control~ The precise regulation

of the flow of the. carrier gas is not a necessary

requirement for the separation of the components of

a mixture by gas-liquid c~romatograp~y. However,

if the retention volume or the efflux t1mes are to

· be used for qualitative identif~catiori, accurate

control is necessary; and, if a quantitative analy­

·sis is to be made, the flow must be substantially

constant. The usual method consists of a coarse

and fine pressure regulator to adjust the pressure

Page 39: Construction of distillation solvent recovery system

. I

I

I

L

FLOW.

METER

PRESSURE

GAUGE

CARRIER

GAS

NEEDL'E

VALVE

PREHEATER q)IL

L------

RECORDER

-30-

----------,

REF

THERMAL

CONDUCTIVITY

CELL

3WAY VALVE

COLUMN

I I L_ -

VENT

EXHAUST .----,-...-. SAMPLE I

I I CONSTANT_ T~"1~E~~R_§ ±I~ ~ATH__ _J L ____ _

FIGURE 6. SCHEMATIC t)IAGRAM OF GAS CHROMAT00RAPHY APPARATUS

Fi"sher-Gulr Partitioner,· Catalogue No.11 1 ~ ~130, p. 3. .F.1sher Scientific Co.,· Pittsburgh, Pa.

Page 40: Construction of distillation solvent recovery system

-31-

within a range of 0-30 pounds per square inch,

gage and a flow regulator. Also, the column it­

self acts somewhat as a flow regulator and there-

fore helps control the flow.

Column and Thermostat. Chromatographic

columns usually consist of lengths of tubing,

four to eight millimeters inside diameter, either

straight or coiledo The tubing can be of any

suitable material, such as glass, copper, alumi-

num, or stainless steel. The advantage of a coiled

column is i~s co@pactness and hence the reduced

size of the thermostat, and metal coils are su­

perior to glass in heat transfer and consta~cy of

temperature. As peak .height .is pa~ticularly sensi­

tive to temperature variations, close control of

the temperature is important if analyti.cal results

are to be obtained; but it is not necessary for

good separation(41). Several different types of

thermostats have been used, including the follow­

ing: (1) oil baths, (2) vapor baths, and

(3) an air thermostat with a sufficient gas ve­

locity.

Sample Introduction. The sample to be ana­

lyzed should be introduced into the carrier gas

stream as close to the top of the column as pos-

sible. Gas samples are usually introduced by

Page 41: Construction of distillation solvent recovery system

-32-

trapping a definite volume of the sample and

then forcing it into the column by the carrier

gas. Some of the methods used in introducing

liquid samples are: (1) by syringe, (2) by

crushing a glass bulb, and (3) by use of a

special pipet.

Component Detection. The detector has to

sense and measure the amounts of components pres-

eht in the effluent gas. There are two basic

types of detectors: differential and integral( 23).

Integral methods include automatic titration of

acids and bases and detection by the ~onductivity

of a collecting solution. Differential methods

are characterized by the gas . density balance, ion­

ization detectors., and thermal conduct! vi ty, which

is most widely used at the present t·ime.

Applications. The results of a gas-liquid chro-

matograph.le analysis is a 1:l"Gries of peaks on a strip of

chart papero Either the. p~ak heights or the ·a.reas w.1 thin

the peaks of the chromatogram may be. used to calculate

quantitative information about the sample. However, since

the areas are less sensitive· to small fluctuations of

temperature and carrier gas flow rate, they are usually

preferred( 41 ). The peak areas may be determined by ·graph-

. ical means or through use of an electronic or mechanical

integrator.

Page 42: Construction of distillation solvent recovery system

-33-

·The area obtained on a chromatogram is propor­

tion.alto the a~ount of the component in the sampleo

However, it has been reported that the thermal conducti­

vity detector does not respond equally t,o all" components ( 62 ).

Therefore, correction fact·ors .or calibration constant"s

must be determined which will put the relative·areas on

an equal·basis. There are seve~al ways of doing this:

( 1) equal amounts of the pure compound may be subje.cted l . . .

to chroma tographi,c analysis and the areas· compared, ( 2) .

r 'elative areas can be computed from analysis or known

mixtures, or ( 3.) calibration constants can be obtained

~rom publlshed lists<58 ).

Once the calibration constants have been deter­

mined, ·quantitative results can be obtained by: (1) de­

termining th~ areas under the respective peaks, (2) mul­

tiplyi~g or diyiding.each area-by its respect.ive calibra­

tion cor;istant, and (3) norm~llzing the __ (}orrected -~~.e.as

to give the percentage·coinpositiono

Page 43: Construction of distillation solvent recovery system

-34-

iii. EXPERIMENTAL

The experimental section of this thesis is divi­

ded into the following sections:_ ( 1 ) purpose of inves­

tigation, ( 2) plan of inve_stigation, ( 3) materials,

(4) construction and installation of equipment, (5)

operational procedure, (6) sample calculations, and

(7) cal-ibration of analytical instruments.

Purpose of Investigation

The purpose of this investigation was·to constru·ct

the necessary equipment to isolate, by fractional distil­

lation (separation by differential vapor pressure), the

products of.a liquid-liquid extraction (separation by

differential solubility) unit. The construction of the

distillation unit was an integral part of and was coordi­

nated with the construvtion of· the extraction equipment.

Plan of Investigation

The plan of procedure was: (1) to review the

literature, (2) to modify the proposed design of Puyear

( 63) and purchase additional necessary equipment, (-3) to

construct the unit, and ·(4) to calibrate the analytical

instruments.

Page 44: Construction of distillation solvent recovery system

-35-

Literature Review. The literature review .was

conducted for this investigation with the following

purposes in mind: (1) investigation of the methods

used in the reprocessing of nuclear fuels, (2) review

of the current literature for information on distillation

techniques, (3) acquisition of information on the phys­

ical properties of the water-methanol-trichloroethylene

system, and (4) study of the methods of gas-liquid

chroma to.graphy •

Redesign and Purchase Specifications. During the

construction of the unit, the design( 63 ). was revised as

necessary changes became apparent. When additional

equipment was needed, it was obtained through the school

store room or the business office.

Construction. The proce.dure followed in construc­

tion of the unit was: (1) erection of the structural

steel; (2) installation of the tanks, pumps, heat ex­

changers, and control valves; (3) rough process piping;

(4) installation of the distillation column and reboiler;

( 5) installation of the process. instrumentation; ( 6)

completion of the process piping; and (7) installation

of the electrical wiring.

Analytical • . An investigation of the analytical

method's was made. The investigation involved preparation

of standard mixtures of methanol-water, analysis by the

various instruments(dipping refractometer, Westphal bal­

ance, and gas chromatograph), and comparison of results~

Page 45: Construction of distillation solvent recovery system

-36-

Materials

The materials used in the construction of the

equipment are listed in the purchase specifications •.

These purchase specifications are found in two parts:

(1) Purchase specifications given by Puyear( 63), ·an4

(2) Purchase Orders Made Between July and December,

1958, and Purchase Specifications: January, 1959 to

January, . 1960 both presented by Okenf'us s ( ~O) .• A ·com­

plete list of these purchase specifications, alon~ · with

lists of costs and .equivalents, is on file with the

Chairman of the Department of Chemical Engineering,

Missouri School of Mines and Metallurgy, Rolla, Missouri.

Page 46: Construction of distillation solvent recovery system

-37-

Construction and Installation of Equipment

This section deals with the construction and

placement of the equipment. Standard items have been

used where possible. Manufacturers and catalog numbers · ( 63) .

.. are listed in the materials list by Puyear and in

Appendix A and Appendix·B. Engineering drawings and pho­

tographs are included where their use ._will clarify the

details of the construction.

Flow Sheet. A schematic flow diagram is presen­

ted in Figure 7. The function of each piece of equip­

ment is shown and each valve has been given a specific

number.

Equipment Placement. The equipment was installed

in the Unit Operations Laboratory of the Departme·nt of

Chemical Engineering at t~e University of Missouri School

of Mines ·and Metallurgy, Rolla, Missouri. Photographs of

the installation are shown ·in Figures 8 and 9.

Tanks. The ·tanks used were standard 55~ and 30-

gallon ICC-5 specification ·black steel drums. ·rn order

to have all of the d.v.ums readily accessible, yet using

the m1p.1mum amount of_ floor space, a tank rack was erec­

ted. Standard structural steel members and an all bolted

construction were utilized to facili.tate future changes.

The ·tanks were not physicai~y attached to the tank rack

as they are held in place by their own weight. All flow

Page 47: Construction of distillation solvent recovery system

FROM EXTRACTION UNIT

DIS TILLATE 1

0-23 ------~ BOTTOMS 1

~~-D~-2_5~~~-

-----...a...D-27

BOTTOMS 3

DISTILLATE2

D-20

D-21

BOTTOMS

REJECT

D-24

BOT TOMS 2

D-26

D-28

BOTTOMS4

• D-30

,~-4--~~~-D_-3_3_j_~D-34

D-29

D-32 ~ 9RP

Fl FLOW I NDICAlOR FR FLOW RECORDER

DRP LLIC LEVEL INDICATOR CONTROLLER

FP

MTR MULTIPLE TEMPERATURE RECORDER

PR PRESSURE RECORDER PRC PRESSURE RECORDER

CONTROLLER

LEGEND

TRC TEMPERATURE RECORDER CONTROLLER

FPH FEED PREHEATER DC DISTIL LATE COOLER DR DRAIN D-1 thru 40 VALVES

TO VENT

/

BP BRP DP DRP FP RP

F R-3,4

MTR-1

BOTTqMS PUMP BOTTOMS RETURN PUMP DISTILLATE PUMP DISTILLATE RETURN PUMP FEED PUMP REFLUX PUMP·

BP

STEAM

TRC-1

TRAP

DR .

TRC­V-2

DEPARTMENT OF CHEMICAL ENGINEERING MISSOURI SCHOOL OF MINES & METALLURGY

ROLLA, MISSOURI

DISTILLATION FLOW SHEET

SCALE: NONE DATE CASE NO: 60 DRAWN BY: J. RA . 2/23 60 FILE NO: 490 CHECKED BY: j:/, _ .. ~/h~/&/'J FIGURE NO: 7 APPROVED BY: ,t-_1-~ , .-/1~ / I .(f SHEET NO: 1 of 1

Page 48: Construction of distillation solvent recovery system

-39-

Figure 8. The Distillatio~ Unit showing the

D1st1ll~t1on Column, the Control Valves,

and the Tank Farm

Page 49: Construction of distillation solvent recovery system

Figure 9. The D1s·tillat1on Unit sho~ing

the Bottom of the Column

and the Reboiler

Page 50: Construction of distillation solvent recovery system

-41-

connections into or out of the tanks were made with

11 Swage.lok 0 fittings which allow the tanks to be removed·

from the system for repair or replacement with a minimum

of labor. Construction of the tank rack and installation

of the tanks is essentially as specified by Puyear(:65).

A photog~aph of the installation is shown in Figure 10.

Pumps. The pumps are Bell and Gossett booster

pumps. The pumps are driven by 1/6 horsepower, explosion­

proof motors wound for 115 volts, 60 cycle, single phase

alternating current. These pumps are of a centrifugal

type with an enclosed impeller. The pumps, which are

located along the front of the tank rack, were placed on

a rack to which they.were securely bolted. The pump rack

consists principally of two pieces of 3 x 3 x 1/4-inch

angle iron laid back to back with a 3/4-inch spacer be­

tween them. The pumps are used as follows: (1) feed

pump ( ~) , to pump the fee.d from the feed tank to the

column; (2) bottoms pump(~), to pump the bottoms

product from the reboiler to the bottoms storage tanks;

(3) reflux pump (B1:), to pump the reflux from the accu­

mulator tank to the top of the column; (4) distillate

pump (Q!:), to pump the distillate ·product from the accu­

mulator tank to the distillate storage tanks; . (5)

bottoms return pump (!ill!:), to pump the bottoms product

from th~ bottoms storage tanks t9 either the extraction

solvent tank or the distillation feed tanks; and ,. ,.

Page 51: Construction of distillation solvent recovery system

-42-

Figure 100 Rear · View of Tank Farm

and Tank Rack

Page 52: Construction of distillation solvent recovery system

-43-

(6) distillate return .pump (QB!:), to pump the distil­

late product from the distillate storage tanks to either

the extra:cti-on or distillation feed tanks. A photograph

of the pump installation is shown in Figure 11.

Distillation Column. The distillation column is

an assembly of standard parts. The purpose of the dis- ·

tillation column is to separate, by differential vapor

pressure, the components of the feed mixture. The col­

umn was constructed of glass pipe six inches in diameter

with nine plates spaced at 12- and .18-inch intervals.

The column.is supported by clamps which were mounted on

two pieces of 3-inch steel pipe extending from floor to

ceilingo The column as installed is shown in Figure 12 •

. The plates are formed from sintered gla~s, and

each plate contains one bubble ·cap. The bubble cap is

slotted around its periphery and is an integral part of

the plate. Each plate is ~lso provided with both a liquid

and a vapor sampling tap and a thermocouple well.

The plates were sandwiched between the sections

of glass pipe, and the entire assembly was held . together

by aluminum flanges. Th~ bo~tom section was rigidly

mounted to the s~pport clamps, while t~e other sections

were spring mounted to allow for expansion and contrac­

tion of the column during. start-up and shut-down opera­

tions. The details of the column suspension are shown

in Figure 13.

Page 53: Construction of distillation solvent recovery system

-44-

Figure 11. Process Pump~ and Control Valves

Page 54: Construction of distillation solvent recovery system

-45-

Figure 12. The ·Distillation Column

Page 55: Construction of distillation solvent recovery system

I

PLATE NUM.BER

9

8

7

6

5

4

3

2

1

DISTILLATION COLUMN

EAST VIEW

t°l l I

Fi I

:>ETAIL TWO SPRING MOUNTED PLATES

::~EE NOT[ Ot,IE

OETAI L C NE HIGI DLY M[:UNTE D

BOTTOM PLATE

SEE NOTE ONE

-4- SEE DETAIL TWO

0

DISTILLATION COLUMN

NORTH VIEW

TOP VIEW OF

BUBBLE CAP PLATE

CROSS SECTIONAL ViEW

0F BUBBLE CAP . PLATE

NOTE ONE : THE BOTTOM PLATE (No 1) IS RIGIDLY MOUNTED; ALL THE REST ARE SPR.ING MOUNTED.

DEPARTMENT OF CHEMICAL ENGINEERING MISSOURI SCHOOL OF MINES & METALLURGY

ROLLA, MISSOURI

DISTILLATION COLUMN . INSTALLATION DETAILS

SCALE: NONE DATE CASE NO: 60 DRAWN BY: J. R. A. 4/9/60 FILE NO: 490

CHECKED BY: 9:·f. S/IIJ/~~ FIGURE NO: 13

APPROVED BY: _"-·-~7. ~~-1,1~ ~ SHEET NO: 1 of 1

Page 56: Construction of distillation solvent recovery system

-47-

Optional feed sections were provided for in the

column. Numbering from the bottom, plates 3, 4, 5, and

8 have a tee section above them by which feed may be

introduced. The tee sections are 18 inches in ~ength,

while the straight_ sections of pipe comprising the re­

mainder of the column are 12 inches in length. This

accounts for the unequal spacing of the bubble-cap plates

in the column.

Reboiler. The reboiler was fabri~ated from stain­

less steel by the Nooter Corporation of St. Louis, Miss­

ouri. It is fitted with a fully flanged head to which

the copper steam coil is attached. The steam coil was

built up from copper pipe and copper sweat fittings. The

purpose of the reboiler is to supply the heat input to

the distillation column. To _prevent undue heat loss to

the surroundings, the.reboiler is insulated with insula­

ting cement. Photographs of the reboiler installation

are given in Figures . 14 and 15.

Condenser. The condenser consists of a V-shaped

double-pipe heat exchanger constructed f~om copper pipe

and copper fittings. The cooling water passes through

an inner one-inch tube, and the vapors condense in the

annulus between .this inner one-inch tube and the outer

two-inch tube. The purpose of the condenser is to con­

dense the vapors from the top of the distillation column.

Page 57: Construction of distillation solvent recovery system

-48-

Figure 14. View of the Reboiler from the

South Bide of the Unit

Page 58: Construction of distillation solvent recovery system

-49-

Figure 15. View of the Reboiler from. the

North Side of the Unit

Page 59: Construction of distillation solvent recovery system

-50-

The condenser is mounted on the front of the tank

rack, and flow of the condensate from the condenser to

the accumulator tank is by gravity. The condenser as

installed is shown in Figure 16.

Feed Heater. The feed heater is a vertical, dou­

ble-pipe heat exchanger fabricated from copper.pipe and

fittings in much the same manner as the product condenser •

. The purpose of this piece of equipment is to heat the dis­

tillation feed stream to the boiling point prior to its

arrival at the distillation column. Steam is used in an

inner one-inch tube, and the distillation column feed

flows through the annulus formed by an outer two-inch

tube. This piece of equipment is mounted at the north­

east corner of the unit. A photograph of the feed heater

is shown in Figure 17.

Feed Preheatero· The heat exchange! used to pre­

heat the feed and to cool the bottoms product is a Graham

heliflow with a cast irpn shell and cojpper tubes 9 Cold

feed flows through the shell side,. and the bottoms product

flows through the tube side~ The feed preheater was

mounted on the southwest corner of the reboiler stand.

Distillate Cooler. The distillate cooler is iden­

tical to the heat. exchanger used- for the feed preheater~

The distillate cooler is used to cool the distillate pro­

duct from the accumulator.tank before it is pumped to the

product tanks. The cooling water used on the shell side

Page 60: Construction of distillation solvent recovery system

-51-

Figure 16. The Product Condenser

Page 61: Construction of distillation solvent recovery system

-52-

Figure 17. The Feed Heater

Page 62: Construction of distillation solvent recovery system

-53-

of this heat exchanger is obtained from the exit. side of

the product condenser.

Instrument Panelo The instrument panel consists

of a piece of 3/8-inch sheet steel attached to~ rrame·

constructed from two- and three~inch angle iron. ,The pan­

el is located between the two main structural.columns in

the unit operations laboratory··,~ and the front of the

panel board is flush with the east·. side of these columns.

The face of the panel was cut out to acc9modate the vari­

ous indicating and recording.instruments. The panel has

a graphic representation of the process flow diagram on

its face above the instruments. A photograph of the in­

stallation is shown in Figures 18 and 19.

Control Instrumentation. Process control of .the

unit is maintained through t~e use of automatic instru­

mentation •. A vari~ty.of control instruments was incorpo­

rated in_ the design; .and these _are illustrated in the di_s- .

tillation flow sheet, ·::_Figure· 7, and in the process. control

flow diagram,. Figure 20. The transmitter po·rtion of ·each

instrument is located .close to the point .o~ measurement;

the recorders, con~roller, and in~icators a~e located on

the· instrument panel; and the control valves are located

on the control valv_e rack. All transmi.ssion of control . .

signals is by compressed air. The individual spe_cifica-

tions of all the process instruments have be~n given by

Puyear( 66 ). The location and· numbering system used on

the thermocoupie leads is shown in Figure 21.

Page 63: Construction of distillation solvent recovery system

-54-

Figure 18. Front View of the ·Instrument ·Panel

Page 64: Construction of distillation solvent recovery system

-55-

Figure 19. Rear View of the Instrument Panel

showing tne Tel-0-Set Instruments,

the Instrument Air Header,. and

the Electrical Wiring

Page 65: Construction of distillation solvent recovery system

0

c

LLIC-V2

TRC-Tt

D

FR 3,4

F·V

FR 1,2

R

c e

..... --•D

Pf-i -TI

LLIC 2

R 4

PR I

R

'3

Pi,C -Tl

PRC

i'

TRC.,.__.._.,. TRC 4 r

A

FRC 3

FRC ...... .._~ FRC. 2 I

TRC-V2

LLIC-T:1

LEGEND TRC-TFMPERATURE RECORDER CON­

TkOLLER

LLIC- -UQUIO LEVEL tNDtCATOR CONTROLLER

FR-FLOW RECORDER

PR-·PRESSURE RECO,AOER

PRC-PRESSURE RECORDER CONTROLLER

FRC-FLOW RECORDER Ct,'NTROLLEfi F-fLOW

V-VALVE

T-TRANSMtTTER

-SUPPLY AIR

-- INPUT 6 OUTPUT PNEUMATIC $1GNJlL

DEPARTMENT OF CHEMICAL ENGINEERIN6 MISSOURI SCHOOL Of MINES & METALLURGY

ROLLA, MISSOURI

PROCESS CONTROL rLOW DIAGRAM

SCALE: NONE DATEl~E NO: 60 DRAWN IY: G G '5TAPLES FILI NO: 490

..._------------a:;a... C CHECKED IY: Fl6URE NO: 20 APPROVED BY: ~ '/rjt,o SHEET NO: 1 d 1

Page 66: Construction of distillation solvent recovery system

DISTILLATION

COLUMN

2 ~-

LEADS INSERTED INTO

WELLS ON EACH PLATE

LEADS INTO TERMINAL BOX

ROTATING

DISC

COLUMN

PULSE

COLUMN .

LEADS INSE4TED l"ITO WELLS IN

INLET AND EX~l FLOW STREAMS

NOTE;LEADS A AND B ARE

CONNECTED TO RECORDER-

CONTROLLERS TRC - 1 AND

TRC - 2 ON DISTILLATION

SYSTEM.

LE ADS PASS FROM

TERMINAL BOX INTO

MULTIPOINT TE ~PER AT URE

RECORDER.

DEPARTMENT OF CHEMICAL ENGINEERING MISSOURI SCHOOL OF MINES & METALLURGY

ROLLA, M_ISSOURI

LOCATION AND NUMBERING

OF THERMOCOUPLE LEADS

SCALE: N () /'J ( DATE

DRAWN SY: R.A.L. I, II, - t>O

CHECKED BY: /(. 'Ji t.ll . J. • /0 ·i," APPROVED BY: '\{, Sii'!/t,.l)

CASE NO: 60 FILE NO: <\(}0 FIGURE NO: 21

SHEET NO: 1 of 1

Page 67: Construction of distillation solvent recovery system

-58-

Instrument Air. The instrument air is supplied

by an air compressor equipped w~th an intercooler and

aftercooler. The compressed air is filtered and reduced

to about 50~60 pounds per square inch, gage. The piping

between the compressor and the instrument panel is gal­

vanized iron. The air is distributed from the instrument

panel by a copper header. Further distribution is by cop­

per pipe and polyethylene tubing. Extensive use was made

of polyethylene tubing for·pneumatic lines .interconnect­

ing the varioµs instrument components. A photograph of

the instrument air compressor is shown in Figure 22.

Process Piping. The distillation column, heat

·exchangers, and tank farm were integrated by means of the

process piping. All piping was of standard copper water

pipe connected with standard fittings -and joined by solder

sweat joints. Threaded unions were placed in the piping . .

·wherever their use might be advantageous in removing sec­

tions of piping or equipment for cleaning_, repair, or re­

placement. The piping runs- were made perpendicular and

parallel to the walls and floor of the unit operations

1aboratory to assure a neat appearance. ·

After the process piping had ~een installed, it

was checked for leaks. This was accomplished by pumping

water through the system, repairing the leaks discovered

after draining the lines, and then rechecking with water.

Page 68: Construction of distillation solvent recovery system

-59-

Figure 22 •. The Instrument Air Compressor

Page 69: Construction of distillation solvent recovery system

-60-

The pieces of equipment were linked together as

specified by the distillation flow sheet, Figure 7. The

general piping pi·cture can be seen in the pho·tographs of

the various equ·ipment installations.

Vent System. ~ vent system was installed for the

purpose of venting the tanks and the column. The vent

system was fabricated from 1/2-inch copper pipe using

copper sweat joints. A schematic diagram of the vent

system is shovm in Figure ·23.

Electrical Wiring. The electrical wiring for the

pump motors, the instrument chart ~iv~s, and lights was

installed according to the standard electrical codeo The

·wires were run through electrical conduit utilizing stan­

dard connections and ele-ctrical junction box~s. The unit

was connected into the Missouri School of Mtnes and Met­

allurgy power plant system.by standard.male plugs into

female outlets. A wiring diagram is shown in Figure 24.

Page 70: Construction of distillation solvent recovery system

-61-

i TO VAPOR CONDENSER ·

' •

I l 1

EXTRACT 1

FEED FEED

TANK TANK1 TANK2

I I l

RAFFINATE DISTILLATE DISTILLATE

TANK T ANK1 TANK2

. I I I

EXTRACT2 REFLUX BOTTOMS

ACCUMU LA. REJECT TANK TANK TANK

'

I I I

FEED BOTTOMS BOT TOMS

TANK TAN K1 TANK2

..

I r l

SOLVENT BOTTOMS BOT TOMS

TANK TAN K3

TANK4

4 FROM CONTROL VALVE: PRC - V-1

NOTE: VENT SYSTEM IS MADE

O F ~·. C OP P E R P I P E DEPARTMENT OF CHEMICAL ENGINEERING

MISSOURI SCHOOL OF MINES & METALLURGY

ROLLA. MISSOURI

VE NT

FLOW SCALE: NONE

DRAWN BY: /f. w_ r)/. CHECKED BY: J R A

APPROVED BY: ~

SYSTEM

DIAGRAM DATE

J..-<f-1,0

4/9/60 S'/10/1. IJ

CASE NO: 60 FILE NO: 490 FIGURE NO: 2 3

SHEET NO: 1 of 1

.

Page 71: Construction of distillation solvent recovery system

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DEPARTMENT OF CHEMICAL ENGINEERING MI.SSOURI SCHOOL OF MINES & METALLURGY

ROLLA, MISSOURI

\,,\/ I R I N G, S'C. \-\ E. MA, 1 c..· . r.:'01'(

D \ S_TlLLRTIDN - E'XTRRC1IOA/ SYSTEM ..

SCALE: . HOA/E. DATE I/- 1./ CASE NO: (f_q DRAWN BY: MMIZ FILE NO: 490. CHECKED BY: ~.)Y.' d. / ;J.. -/'7. ~1' FIGURE NO: 2. 4 APPROVED BY: 1:1:f'._ / l- 17·-S'I SHEET. NO: l o+ 1

Page 72: Construction of distillation solvent recovery system

-63-

Operational Procedure

The basic procedure for the operation of . the dis­

tillation unit is: (1) the attainment of operating

temperature, ( 2) the approach to a steady~st~te ·:; ·· :

equilibrium, (3) introduction of the column feed, ·and

( 4) establishment o.f appropriate operating conditions.

The recommended, det_ailed procedure for operation

of the distillation unit is presented in the following

order: ( 1) preliminary pro_cedure, ·c 2) start-up pro­

cedure, . (3) continuo.us operation, and (4) shut-down

procedure. All equipment will be referred to as desig­

nated on the disttllation flow sheet, Figure 7.

Preliminary Procedure. The following preliminary

operations should be performed in order to prepare the

unit for operation:

1. All valves, including flow valves and by-pass

valves, are closed.

2. Both feed tanks are filled with water by means

of a connection to the distilled water outlet.

3. The number l·distillate tank and the numbers

land g bottoms tanks are filled with feed mixture by

connections to the suction sides of the distillate pump

and the bo~toms pump.

4. Cooling· water for the condenser should be

available at the control valve TRC-4.

Page 73: Construction of distillation solvent recovery system

-64-

5. Steam for the feed heater and the reboiler

should be available at the control valves TRC~1 and

TRC-2o Any condensate is bled off .through the drain

valves.

6. Approximately half of the contents of feed

tank ~umber 1 is ·pumped to the distillation columno

This is accomplished by opening valve D-15, the_by-pass

valve at F-V-1, the flow valves through EB::.1., the desired

feed _plate valve (12.::.1.,- J2.::.g, D-3, Qr. 12.:!), and valve D.-5

and by turning on the feed pump. After the desired amount

of water has been transferred to the co-lumn from the num­

ber l distillate tank, the by-pas_s valve at F-V-1 is

closed; and the feed pump is turned off.

7o At this point, the following instruments should

be turned on and checked for proper operation:

a. ~ should read room temperature for

all _points.

b. TRC-2 and TRC-3 should indicate room

temperature.

c. ~ should indicate atmospheric pres-

sure.

d·. PRC-1 should indic·ate atmospheric

pressure. This instrument may be set·to control

at atmospheric pressure.

e. LLIC-2 should indicate the liquid level

in the rebeller.

Page 74: Construction of distillation solvent recovery system

-65-

Start-up Procedure. The unit is brought up to

temperature with boiling water, and the column is then

run at total reflux on water until ·static equilibrium

is approached. This may be accomplished by the following

procedure:

. 1. TRC-v-·4 is set to control the flow of cooling

water to the condenser.· The temperature set-point at

this time is the boiling point of water at atmospheric

pressure.

2. The by-pass valve at TRC-V-2 is .slowly opened

to allow entrance of steam into. the steam coil of the

reboiler. The water .in the reboiler is·brought to the

boiling temperature, and the vapors are allowed to fill

the column. The liquid level in the reboiler shou~d be

main~ained at greater than half of total capacity. If

the level drops below this, additional water should be

added from feed tank number l· (It may be _desirable to

add this .additional water at an elevated temperature. To

incre~se the temperatur~, the by-pass valve at TRC-V-1 is

opened slightly to allow: steam to enter the fe·ed heater.)

3. The vapor from·the reboiler should fill the

column, pass overhead, and be condensed in the ·condenser.

The condensate will then collect in the reflux accumula­

tor. Flow from th~ condenser to the reflux accumulator

should ·-be through FR-3. This is accomplished by opening

the flow valves on either side of FR-3.

Page 75: Construction of distillation solvent recovery system

-66-

4. When sufficient material has collected in the

reflux accumulator, reflux to the col'1Illn can be started.

The by-pass valve at TRC-V-3 is opened, and the reflux

pump is turned o·n. The flow valves. through ~ and .12::.§_

are opened, and the reflux rate is adjusted by use of the

by-pa~s valve at·TRC-V~3.

5. At this stage, the column should be approach­

ing an equilibrium condition; and the following process

instruments can be checked f"Or operation:

a. -~ should show a small temperature

·decrease up the column. The temperature on the

top plate should be the boiling point of water

at the prevailing .atmospheric pressure.

b~· TRC-2 should indicate a temperature

intermediate to that shown on~ for the first

and third plates of t .he distillation column.

TRC-2 can now be-set to control the steam flow

to the reboiler. The set-point of the instrument

should be the temperature indicated.· ·The· flow·

valves at TRC-V-2 are opened, and the.by-pass

valve is closed.

c. PRC-1 should maintain atmospheric

pressure for the pressure at the :top·~ of the column.

d. PR-1 ·should indicate the pressure at - .

· the bottom of the columno Tl;l.e difference between

this reading and that given by PRC-1 is-the pressure ·,

drop through the column •.

Page 76: Construction of distillation solvent recovery system

-67-

e. LLIC-2 should show the liquid level in

the reboiler. .-

f. FR-3 and~ should indicate the liquid

rates of ·flow in their respective process lines.

Continuous Operation. The pro.cedure f'or c~nyertirig

to the methanol-water mixture from the refluxing water is

now given, and instructions for continuous oper~tion are

presented:

1. The excess water in the feed tanks is pump.ad

out through valve D-36 by opening valves D~15 and l2:.1..2. and turning on the feed pump. When the· tanks are empty,

valves Q::.15. and 12.:.1..Q. are closed.

2. The feed mixture from numbers land 2 bottoms

tanks is pumped into the feed tanks by opening valves

D-25_, D-26, D-9, and Q:1.g and turning on the distillate

return pump.

3. Feed is now slowly introduced into the column

in the following manner: TRC-1 is set to maintain the

feed temperature at it~ ~oiling· point, _valve ·D-15 is

opened, and the feed pump is turned on. The flow valves.

on either ~ide of F-V-1 are opened, F-V-1 i~ slowly opened,

and the flow is regulated at a rate ·or o.2-o.3·gallons per

minut~.

4. LLIC-2 is set to control the level in the

reboiler. The flow valves on either side of LLIC-V-2

and ~ ~nd valve ~ ar.~ opened. The excess of water

Page 77: Construction of distillation solvent recovery system

-68-

in the unit will collect in the reboiler and can be

pu,mped out.

s. A temperature gradient should now begin·to

appear on m. ·The reflux rate sho.uld be carefully .

controlled at this time to help regulate the top tempera­

ture. As the top temperature approaches the operat·ion

temperature, TRC-3 may be set for automatic operation.

6. The level of liquid in the reflux accumulator

tank will now begin to build up. When the tank is approxi­

mately half full, LLIC-1 can be activated to maintain this

level. · Valve Jl:.a, the flow valves through LLIC-V-1.and

El::l, and valve D-17 should be opened.

7. All or· the process instruments should now be .

functioning, and the unit is on continuous operation.

Minor adjustments should be made to the instruments to

maintain steady operation. ·

Shut-down Procedure. The following procedure is

presented for terminating operation of the unit:

l. Valves D-15, D-16, 12::,g, TRC-V-1, · and F-V-1 ·

are closed; and the feed pump is turned off. ·

2o Flow of steam to the reboiler is discontinued

by closing valve TRC-V-2.

3. Valves TRC-V-3 and~ are closed, and the

reflux pump is turned offo

4. The unit is now allowed to cool.

Page 78: Construction of distillation solvent recovery system

-69-

5. The remaining material in the reboiler is

pumped, through t~e bottoms pump and £::.gl, to the bottoms

reject tank.

6. The product in the reflux accumulator is

pumped to the distillate tank-by the distillate pump~

7. The cooling water to the condenser is t~rned

off. ·

8. All proc~ss· valves, flow valves, and. by-pass

valves are closed.

Sample Calculations

Theoretical material and energy balances around

the distillation -column have been determined. The cal-

c~lations were based on the system meth~nol-water. The

feed for the distillation was the extract stream ·from the

extraction unit. The extract stream has· been specified

by Okenfuss(60) to con~ain approximately 20 mole per cent

methanol and 80 mole per cent water, with.leas . than one

~alf of one mole per cent trichloro~thylene. This a~ount

of trichloroethylene was considered negligible for these

calculations and was not taken into account.

The distillate.p~oduct was specified t~ be of such

a composition that by mixing it with a calc~_~ated .amount . .

.of the raffinate stream from the extraction ·unit (approx-

imate_ly 100 per - cent trichloroethylene) additional feed

for the extraction unit was obtained. The desired.feed·

Page 79: Construction of distillation solvent recovery system

-70-

for .the extraction unit wa~ 50 mole per cent methanol,

40 mole per cent trichl.oroethylene, and 1 O mole per. cent

w~ter ( 60) '.. Therefore, the required distillate ·product

composition was calculated by material balance to be · . .

83.3 mole per cent methanol and 16.7 mole per cent water.

The bottoms product was specified to be essentially pure

solve.nt for the extraction·unit (water).

With regard to the ~iscussion. above, the· following

variables were specified in order that the calculations

would be in agreement with those made for the extraction

unit:

1. A feed composition of.20.0 mole per .cent

methanol and 80.0 mole per cent water.

2. A diatillate product composition of 83.3 mole

per cent methanol and 16.7 mole per cent water.

3. A bottoms produc~ of 99.0 mol~ per cent water

and 1 .o mole per cent methanol.

The following variables were th~n chosen specif­

ically for the sample calculations:

1 • A feed rate· of O. 25 gallons · per minute of

the above feed composition.

2. · The feed ·mixture to enter the column at the

bubble point ·.

3. An.external reflux ratio of 1025.·

.Determination of the Flow Rates and Heat Require­

ments~ The method of Ponchon-Savar1t(9·39 9'M was used in

Page 80: Construction of distillation solvent recovery system

~71-

the determination of the material and energy balances.

The enthalpy-composition diagram, Figure 5, ~as obtained

from t4e data of Ansell, Samuels, and Frishe(4).

The solution as worked on the Ponchon-Savarit

diagram is shown in Figure 25. Point F was established

by the concentration (xF = 0.200) and the temperat~re

(bubble point) of the feed. Points D and B were located

on the saturated-liquid line at xn ~ o.833 and·xB = 0.010

respectively. Point D 1· was ·found from the specified

reflux ratio by use of the following equation(94):

in - 1y iy - in

The values of iy_and in can be read directly from the

( 1 )

enthalpy-composition diagram, Figure 25, at the compo-

sition of the -distillate product.

= 1 a,000· ~b-mol~ ·

Btu

= 2,200 Btu

lb-mole

therefore: 1' D = 1-.25 (18,000 - 2,2oq) + 18,000 (2)

1' 37,750 Btu (3) = D lb.-mole

iB an~ B' were then located analytically at -8,075 Btu

per ·lb~mole by a · line through D'. apd F, the feed point.

Calculation of the ·Distillate Product Rate

and the Reflux Rate. The feed rate was spec-ified

at 0.25 gallons per min~te for these calculations.

Page 81: Construction of distillation solvent recovery system

DJ., "'110

20,000

18,000 I; . //

..! 11 ,; ,, I I

I I ,, ,, I I

,, ,, , / I !I 16,000 ,: I,

!/ I

" // I ,, ,, I : I : 1! ,' r I· I I

,: I ;

// I I I

I

I I

,// I I

I II I ;

I I I I , I I

1' I 14,000 I I'. ,· I I

i I ; ,' I I

!i I

.. I I

// I

a, I I I I

g I • I I

12,0.00 r ! , i I I I·

£j I I ,, i I

I I; I I I I

" I ! I I :J

i ; ' i ,' I ti) I j I

I , I I; I I

, I I: I I ,' I I l I I I I I i l I , I , I

~ I . i ,' I I .'.).. I I I

I co j I I ,

I :r:. I

I I I I ..... I

c I I ! I I I

w I I I I I I i I I I I I I I I j

I I I

I I I I I . I I ., I . I

I I I I I

I I / I I I I 1· /,

I. I I I I I

1/ I

I /1 I , / I I

I

·x D L1

0.1 0.2 Q3 OA 0.5 0.6 0.7 0.8 0.9 Mole Fraction Methanol I -80<.)0i i' '. s· B

· FIGURE 25. PONCHON- SAVAR IT ~LUTION TO THE SAMPLE CALCULATtO NS

Page 82: Construction of distillation solvent recovery system

-73-

This ·1s equivalent to a feed rate of 5.627 lb-moles

per hour.· The distillate product is related to the

feed by the following equation ( ~90) :

where:

therefore:

D F

F

D

.D

= (4)

= 0.200 mole fraction methanol

= 0.833 mole fractio~ methanol

0.010 mole fraction methanol

= 5.627

= 5.627

= 1.300

lb-mole hr

0.200.- 0.010

0.$33 - 0.010 · lb-mole

hr

(5)

(6)

The average molecular weight of the distil­

late product is 29.66 lbs per lb-mole. Therefore,

. the distillate rate was calculated as 38.6 lbs · per

houro Also, since the reflux ratio was 1 .25, the

reflux rate was calculated at 48.3 lbs per hour.

These rates can be easily converted to gallons per

minute.

D - 0.095 gal min

(7)

R = 0 .119 g~l . min

(8)

Calculation of the Bottoms Rate. The

bottoms rate was calculated from the feed and

product rates by the following material balance

Page 83: Construction of distillation solvent recovery system

equation(9~):

·B

where: F

D

B

B

-74-

= F - D

= 5.627

= 1.300

lb-mole ·hr

lq-µiole hr

= 5.627 - 10300

= 4.327 lb-mole

hr

(9)

(10)

( 11 )

Converting this value to gallons per minute gave

a rate of 0.157 gallons per m'inute.

Calculation of the Heat Requirements·. The

specific enthalpies of the overhead and _bottoms

were 2,200 and 3,150 Btu per lb~mole, respectively,

as read from Fiqure 25. The heat withdrawn in the

condenser was then calculat~d using the following

equation c9 2):

where:

D

= 37,750

= 2,200

Btu lb-mole

Btu lb-mole

lb-mole 1.300 .

· hr

( 1 2)

q 0 = 1.300 (37,750 - 2,~00) (13)

= 49,050 ~tu hr

(14)

Page 84: Construction of distillation solvent recovery system

-.75-

The heat a~ded in the reboiler is calculated

from the following equation(92):

qr = B (iB .. ) - l.B ( 15)

where:

iB 3,200 Btu = lb-mole

1' -8,075 Btu = B lb-mole

B 4.327 lb-mole =

hr

qr = 4.327 [3, 200 - (-8,075~ ( 16)

48,700 Btu (17) qr = hr

Calculation of the Theoretical Plates. The theo-

retical plates were stepped off on the Ponchon-Savarit

diagram, Figure 25, in the following manner. Since

xD = Y1, the point representing V1 is on the saturated­

vapor line at x = 0.833. From point V1, the appropriate

tie l~ne establishes po.int L1 on the saturated- liquid

line. An operating line through points D' and ·L1 inter­

sects the saturated-vapor line ·at point V2," and ·the tie

line through this point establishes point L2 ~ An oper­

ating line through point~ ·D' and L2 intersects the sat­

urated-vapor line at point L3 •

Since L3 is at the .left of line D'FB' ·, the next

operating line is drawn through point B', thus estab­

lishing point V4 on the saturated-v:apor 11ne. From

point V4, point L4 is located by a tie line; V5 from

Page 85: Construction of distillation solvent recovery system

-76-

an operating line; L5 by a tie line; V6 from an oper­

ating l~ne; L6 b~ a tie line; V7 from an operating line;

and Irr by a tie line. Since x7 is less than ~B' s~ven

steps are sufficient. A reboiler ·and ·six ideal plates

with feed admitted on the fourth plate are specified·.

Results of the Calculations. The results of the

theoretical material and energy balances are given in

Tables VI and VII. Calculations were made for a range

of feed rates from 0.20 gallons per minute to 0.50 gallons

per minute and for external reflux ratios of 1.00, 1.25,

1.50, 1 .75, and 2.00. In all cases, it was assumed that

the feed mixture entered the c_olumn at· the bubble point.

Calibration of Analytical Instruments

The instruments used for the analytical deter­

minations were: {1) a Westphal balance·, (2) a dip­

ping refractometer, and (3) ·a gas-liquid chromatograph.

A description of these instruments is given in. the mat­

erials list. The instruments were cali.brated by firs.t

analyzing pr_epared sanipies of methanol-wa t ·er.. These ··.;­

mixtures were prepared ·by carefully weighing .. the amount . . · · , : ..

of liquid contained in pipets of .various size~ at 25 °c, and then calculated amounts of methanol and water were

pipetted into glass st9ppered bottles. Calibration charts

were prepared for .each of the instruments from analysis

of these known samples. Unknown samples were than

Page 86: Construction of distillation solvent recovery system

-77-

TABLE VI

Effect of ·Reflux Ratio on the Theoretical Plates

Required for Separationa

External Theoretic~l Reflux Ratio Plates

1 .oo 9

1 .25 7

1.50 . 7

1 • 75 6

2.00 6

O<. 4

· aA feed of 20 .o mole per cent methanol and 80.0 mole per cent water into a distillate product of 83.3 mole per cent methanol and 16.7~mole per cent water and a bottoms of loO:mole per cent methanol and 99.0 mole per cent wa·ter.

Page 87: Construction of distillation solvent recovery system

-78-

TABLE VII

Results of Theoretical Material and Energy Balances

Feed Product Bottoms Condens·er Duty in Btu per hour Rate Rate Rate at Reflux Rates of:

1.00 1.25 1.50 1. 75 2.00 gal gal gal min min min

0.200 00075 0.126 32,900 37,000 41,200 45,200 49,300 ..

0.250 0.095 0.157 40,050 49,050 51,000 56,000· 61,000

0.300 0 0 113 0.169 49,300 55,400 61,600 67,700 73,800

0.350 0.133 0.219 57,000 64,500 72,000 79,000 86,000

o.4oo 0.152 0.251 65,800 73,900 82,200 90,200 98,500

o.450 0.170 0.278 73,500 83,000 92,750 101,500 110, 500

0.500 .0 .188 0 0·314 82,20~ 92,300 · 103,500 11 2, 500 123, 100

Page 88: Construction of distillation solvent recovery system

-~.19-

analyzed by° each.of the instruments and the.results

compared.

Westphal 'Balance. The specific gravity of the

known samples was deterIQ.ined at 25 °c by thermostating

the samples prior to analysis. The results obtained

are presented 1~ graphical form in Figure 26. For

purposes of comparison, the values of Carr and Riddick

as given in Table IV were also plot_ted.

Dipping R~fractometer. The dipping refractometer

was used in conjunction with a cons·tant temperature ·bath

which.regulated the temperature at 25.00 ·= 0.01 °c. Due to the volatile nature of· the mixtures, a.metal

beaker which pr~vided a vapor-tight compartment for the

sample was· used. · The calibration curve obtained for .

this instrument is shown in Figure 27. For comparison,

the values from the Intern~tiona~ Criti~al Tables were

also plotted.

Gas ~hromatography. _ A considerable amount of

literature search and experim~ntal work w~s ne~essary

before a calibrat~on ·curve·_ could be determined for the

gas chromatograph. Owing to its highly pol~r nature,

water is·stro~gly retained by most partitioning agents,

with the result that the water peak has a long tail.

This makes it very difficult .to obtain .a quantitative

measurement of the peak area and also g~eatly lengthens

the time of the analysis. Therefore, it was desirable .

Page 89: Construction of distillation solvent recovery system

>-t: > ~ 0:: (.!)

u u: u w a.. l/)

-80-

1.000r---....... --~---.--...... --.----.-----------

0.950

0.900

0.850 0

+

0.800

0 0.1

' '

experiment~, values

values of Carr and

\

'\ Riddick 0

\ \

\

0.2 0.3 o.4 o.5 o.6 o.7 o.e 0.9. 1.0 WEIGHT FRACTION METHANOL

F!Gl)RE 26. SPECIFIC GRAVITY AS A FUNCTION OF COMPOSITION

FOR THE SYSTEM METHANOL-WATER AT 25 °c.

acarr, c., and J. A. Riddick: Physical Properties ot· Methanol Water System, Ind. Eng. Chem., il, 693 ( 1951} •.

Page 90: Construction of distillation solvent recovery system

)( w a z

w > .... u <{ a: L1. w a::

-81~

1.34250,----T----...---..... ----..... ----..---..... ----..... --.... ----..---......

134000

1.33750

1.33500

1.33250

o experimental values

6 valu~s from lnh:rnational Critical Tables0

1:33000

1.32750

1·3 2500 o~---,"'."io--2-'o--...130---....i4L.o--5._0 ____ 6 ... o----.170--..1so-.--g1.o---'100.·

METHANOL. weight percent

_FIGURE 27. REFRACTIVE INDEX AS A FUNCTION OF COMPOSITION

FOR THE SYSTEM METHANOL-WATER AT 25 °c

a~!International Critio~l Tables," ll, p.66. McGraw­. Hill Book Company, Ino., New York, N. Y., 1929.

Page 91: Construction of distillation solvent recovery system

!"982-

to find a suitable liquid phase and solid support which

w.ould g~v,e a measurable water peak.

Ethylene glycol, silico~e grease, tricresrJ phos­

phate, and "Ucon" lubricants were tri·ed without satis­

factory results. An article in ".The Laboratory11(30)

suggested the use of "Theed" (tetrahydroxyethylet:J:J;ylene~

dianiine) on "Chromasorb W" as a good combination far

analysis of polar liquids~ A column containing 35.5

per cent "Theed" by weight was prepared· and tested.· This

combination was found to give the best water peaks of the

materials tried. A calibration curve was· plotted and is

shown in Figure 28. It t~kes·approximately 30. minutes

for a sample to ~e completely eluted from the .column

at 101 °c with a helium flow rate of 110 milliliters per

minute. The retention times for methanol and water are

2.75 and 17.50-minutes respectively.

Unknown Samples. Unlmown samples were prepared

at approximately 25, 50, and 75 per cent by weight

methanol. These samples were ~hen_analyzed by each of

the three instruments. · The results obtained are tabulat-. .

ed in Table VIII.

Page 92: Construction of distillation solvent recovery system

~ <t

~ w <t -~ w CL _J

0 a:: z w <( ~ I <{

~ ~ w u ~

0 LL

<t 0 w <t a:: <{ w

a:: <t

8.0 7.0

6.0

50

4.0

3.0

2.0

1.0

0.8

0.6

0.5

OA

0.3

0.2

0.1

0.08

0.06

0.05

0.04

Q030

0

0.1

-83-

expet-imental values

extrapolated values

0..2 · 0.3 OA 0.5 0.6 0.7 WEIGHT FRACTION METHANOL

0.8

\

' ' ' ' 0.9

FIGURE 28. RATIO OF AREAS OF METHANOL- WATER PEAKS ..

1.0

AS A FUNCTION OF COMPOSITION BY GAS-LIQUID CHROMATOGRAPHY

Page 93: Construction of distillation solvent recovery system

-84-

TABLE VIII

Analysis.of Unknown Samples.of Methanol-Water

Mixtures as Per Cent Methanol

Analysis by Sample

No. Westphal Dipping Gas-Liquid Balance* Refractometa~* Chz,.oma. tqgr.aphy

wt% wt % wt %

21.5 :t OoO 23o0 ± O.O 2_?. oO : o.o 2 41 o5 + 0.2 45.3 :!: Oo5 45.~ ± 1.0 -3 70.0 :f: 0.2 69.6 :i: o.s 67..0 :I: 0 o5

*Analysis determined at 25 °c.

Page 94: Construction of distillation solvent recovery system

-85-

IVo DISCUSSION

The discussion section is divided into the fol­

lowing categories: (1) discussion of equipment, (2)

discussion of instrumentation, ( 3) recommenda-tions,

and (4) limitations .•

Discussion of Equipment

The distillation equipment has been installed for

the express purpose of serving as an instructional aid.

The discussion of the equipment will be made with this

in mind and wil~ cover the following items: (1) distil­

lation column, ( 2) reboiler, · ( 3) condenser, . (·4)

auxiliary heat ·exchangers, (5) proces$ p~ps, (6)

tanks and tank rack, and (7) . vent system.

Distillation Columno _ The distillation column has

several desirable :features -~which enhance its instructional

value:

1. The column has been constructed of glass so

as to provide an unobstructed view of the phenomena occur­

ring within.

2o Multiple feed plates were provided so the stu­

dent can observe the effect produced by ~hanging the feed

plate·.

Page 95: Construction of distillation solvent recovery system

-86-

3. Each plate was provided with a thermocouple

well and liquid and vapor sample taps, enabli;ng .the stu­

dent to obtain a temperature and .composition pro.file of

the column.

In the material and energy balance calcula~ions,

it was assumed .that the heat loss from the column .walls

was negligible. However, since the column ·Wa~ not insu­

lated, this :. as· sumption was far from true; but the actual

amount of heat lost is unknown. It is believed that the

heat loss will not be a hindrance to successful operation

and that it will be compensated by the instructional value

obtained.

It has been noted that the feed plates were spa·ced

unequally in the distillation columno · While this is not

a particularly desirable feature, it was unavoidable.

Twelve-inch tee sections of six-inch glass pipe were not

available, and the use of 18-inch sections only would

have made the column too tall for the space ava+-lable.

Therefore, rather than reduce ·the number of plates in

the column, the unequal spacing was used. 'It is not ·felt,

however, that this will.be a critical fac~or for proper

operation of the column. The main· objection ·probably is

a less attractive appearance.

Reboiler. The . purpose of the reboiler is to supply

the q.riving force for operation of the column. · This is

accomplished by heat tra~sfer from steam in a copper coil

Page 96: Construction of distillation solvent recovery system

-87-

to ·the bottoms material. Copper was chosen for the steam

c_oil because of its high thermal con~uctivity and mechani- ·

cal strength. One end of the reboiler is flanged -so_ that

the steam coil ·can be removed inta_ct from the reboiler for

inspection and cleaning. Also, when the steam coil is

in place in the -reboiler, it is attached only to the flange

face. A metal support in the reboiler allows free expan-

sion or contraction of the steam coil in a horizontal di-

rection. This should effectively relieve strain from the

coil during expansion and contraction.

· Condenser. The condenser contains approximately

3.9 square feet of heat -transfer surface. The cooling

medium is water flowing inside the inner tube. Assuming

an over-all coefficient of heat transfer between the con­

d~nsing vapors and the cooling water of 200 Btu per (hour) {o .

(square foot) (°F), at a temperature difference_ of 64°F,

the· heat transfer rate is calculated to be 49,920 Btu per

hour. .By reference to Table VII, it is seen that this will

limit the feed rate and the reflux ratio used. · rt is felt

that the size of the condenser will seri~usly limit the

effectiveness of the distillation unit as an. ·instructional

aid. However, · the conde_nser is adequate at selected feed .

rates and reflux ratios; and it .can be used .as ·1nstalled

to condense the product vapors from the distillation col-

umn.

Page 97: Construction of distillation solvent recovery system

--88-

·Auxiliary Heat Exchangers. The auxiliary heat

exchangers are: (1) the feed heater, (2) the feed

preheater, and ( 3) the disti·llate cooler. The purpose

of these heat exchangers is to supply or remove hea·t

from the process streams.

Feed Heater. The purpose of the feed

heater is to regulate the temperature of the feed

to the distillation column. This is a highly de­

sirable instructional feature as the effect caused

by changing the feed temperature ~an be easily

predicted theoretically, and the empirical results

can thus be compared with the calculated ones.

Feed Preheater. The most important fun<:~·­

tion of the feed preheater is to cool the bottoms

product, which .has a temperature very close to its

boiling point upon exit from the reboiler. If

no attempt is made to cool the bottoms product,

it is very likely that "vapor locking" will occur ' . . .

in the bottoms pump. •ivapor locking" is a co.ndi-

tion which occurs in a centrifugal -pump when a volatile material · vaporizes in the impeller hous­

ing and prevents the pump from operating effi­

ciently.

Distillate Cooler. The purpose of the

distillate cooler is essentially the same as that

of the feed prehe~ter: to cool the distillate

Page 98: Construction of distillation solvent recovery system

-89-

product so that it can be pumped and stored.

The cooling medium used in this case ·is the. cool­

ing water from the exit side of the cond~nser.

This serves as an example _to illustrate the . con­

servation of cooling water in the unit. If neces­

sary, a . separate source of cooling water could be

supplied in order to more effective~y cool the

distillate product.

Process Pumps. The process pumps are of the cen­

trifugal type, allowing placement of valves for flow con­

trol·on th~ discharge side. With no .load, the pumps

have a maximum head of 17-1/2 feet. The head· drops to.

approximately 17 feet at a delivery rate of five gallons

_per minute. The pumps are of explosion-proof constrµc­

tion as a safety precaution since they are located on

the floor in front of the ·tank rack. If any leaks were

to develop from the t~nk rack, the vapors would concen­

trate .near the floor since the vapors of.both methanol

and trichloroethylene are heavier than air. For the

purpose of preventing any such concentration of vapors,

a window fan has been installed on the west ·side of the

·unit Operations Laboratory.

Tanks and Tank Rack. The tanks use~ as storage

and surge tanks in the unit were not intend~d to be per­

manent. They were designed and installed so as to be

easily removable. For this reason, the tanks were not

Page 99: Construction of distillation solvent recovery system

-90-

physically attached to the tank rack; and all connections . .

into and out of the tanks were made with 11 Swageloku fit-

tings. The tank rack has an all-bolted construction in

order that mod.ifications may be e~sily made when ne_cessary.

The capacity of the tank farm is such that it lim­

its the length .of time which the unit can be run without

either obtaining additional feed from the extraction unit

or making up feed from the distillation and bottoms prod-

uct. For this reason, it may prove desirable at some

future time to increase the capacity of the tank farm.

Vent System. It was necessary.for safety reasons

to maintain a closed system. However, whenever material

i_s pumped into or out of the tanks on the tank rack, they

must be vented. Therefore, a vent system -was employe_d to

provide a safe means for venting the tanks. All of the

tanks were tied together with a common vent system which

passes first through a condenser and then is piped out­

side the building. Any volatile material is then condensed

and recovered while noncondensable gases are carried-out-

side.

.Discussion of Instrumentation

Two different types of instrumentation were incor­

porated for use o;n the distillation unit: (1) process

instrumentation and (2) analytical instrumentation.

Page 100: Construction of distillation solvent recovery system

-91-

Both types of instrumentation have a functional and

necessary use in the operation of the distillation unit;

but they both also serve the purpose of providing· ·an

instructional benefit to the student by offering ·~ him

practical experience in the use and mode of operation

of the two type.s of instruments.

Process Instrumentation. The primary function of

the process instruments . is to control automatically the

unit operation and to provide information on the physical

conditions of the unit. Flow rates, temperatures, and

pressures are measured and indicated qr recorded. This

information can be used in conjunction with re·sults ob;.;;;

tained from analytical determinations to . calculate mat~­

rial and energy balances for the system.

Analytical Instrumentation~ Whereas the process

instruments provide information on the pliysical condi­

tions of the distillation unit, the analytical instru­

ments serve to provide information on the· chemical con­

ditions of the system. Three analytical instruments ._ are

used to perform the necessary chemical analyses: (1) a

w.estphal balance, for determination of specific gravity;

(2) a dipping refractometer, for,q.etermination of re­

fractive index; and· (3) a gas chromatograph, · for sepa­

ration, detection, and measurement of the various com­

pone~ts of a sample. Thus, a sample receives three sepa­

rate analyses,-< through the use. of three different ana.lytical

Page 101: Construction of distillation solvent recovery system

.-92-

instruments. Analyses performed in this triplicate manner

provide a basis for comparison of the potential accuracy

of each set ·or results.

The most beneficial and informative analyses would

be those of samples obtained from the feed tank, product

tank, bottoms tank, and each plate of the distillation

column. As has been noted, the analyses can b~ used in

the calculation of material and energy balances for the

system.

Recommendations

The distillation unit is to be used in conjunction

with the extracti'6n unit to support instru~tion, specifi­

cally in the various aspects of the aqueous reprocessing

of nuclear fuels, of stude~ts in chemical and nuclear en­

gineering. These recommendations are made with this in

mind.

Distillation Column. It is recommended that the

following variables be studied during ·the operation of

the distillation unit:·

1 • The effect of changing the feed plate.

2. The effect of varying the reflux ratio.

3. The effect of feed rate and temperature.

4. The effect of the top and bottom column tem-·

perature.

Page 102: Construction of distillation solvent recovery system

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It would ·also be desirable to study the effect of . .

insulating the column. Insulation which would still af-

ford some visibility of the interior of the column could

be applied. For example, two slits in the insulation

could run the full length of the column opposite each

othero

Condenser. It. i-s strongly recommended that the

size of the product condenser be in.creased or supplemen-

ted. It is estimated that, in· order to provide the de­

sired flexibility of operation which should be inherent

in this unit, at least 25 square feet.of heat transfer

surface be provided. A graphite heat exchanger might be

investigated. Graphite offers good corrosion resistance,

and heat exchangers which have a large amount of heat

transfer surface in a small volume can be fabricated.

The author has had some experience with.such a heat ex-

changer and has found ~t to be quite adequate •

. The present condenser as designed and constructed

is a total condenser. It may prove desirable to have

available a partial condenser for instructio~al purposes.

One could be installed to. operate either in conjunction

with or completely separate from the present condenser.

Another modification could be the conversion of one of

the feed sections to a side stream draw-off. This could

be aocomplished by disconnecting the feed section from the

feed manifold and substituting a condenser. A multiple­

component mixture could then be run through the column.

Page 103: Construction of distillation solvent recovery system

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Limitations

The distillation equipment is limited by materi­

als of construction and by size. A list of the limits (86)

of each piece of equipment has been presented by Puyear ,

and it is also presented here in Table IX.

Page 104: Construction of distillation solvent recovery system

-95-

TABLE IX

Limitations of Equipmenta

Item Capacity or Limiting Feature

Distillation Column Approx1ma·tely 50 gal feed per hr, maximum

Reboiler Approximately 6.2. sq ft of heat transfer surface

Condenser

Feed Heater

Feed Preheater

Distillate Cooler

Feed Tanks

Overhead Product . Tanks

Approximately 3.9 sq ft

Approximately 1 .o sq f ·t

Approximately 2.5 sq .ft

Appro~imately 2.5 sq ft

110 gallons total

110 gallons total

of .heat transfer surface

of heat transfer surface

of heat transfer surface

of heat transfer surface

Accumulator Tank 30 gallons

Bottoms Reject Tank . 30 gallons

Bottoms Product Tank 220 gallons total

Pumps

Feed Line

Approximately ·17 ft of head, maxim~

Limited to tw·o ~al per min by flow recorder

Bottoms Product Line Limited to two gal per min by flow recorder

Distillate Product Line

·Reflux Line

Limited to one gal per min by flow recorder

Limited to one gal per min by flow recorder

Materials of Construction

Pyrex glass

Steel tank c·opper coil

Copper tube

Copper tube

Brass tube in cast iron case

Brass tube in cast · iron case

Sheet Steel

Sheet Steel

Sheet Steel

Sheet Steel

Sheet Steel

Bronze

Copper tul;>e

Copper tube

Copper tube

Copper tube

aPuyear, D. E.: Design of Distillation Solvent Recovery System, p. 134, Unpublished M. Sc. Thesis, Library, Missouri .. School ~t Mines and Metallurgy, Rolla, Mo. (1958).

Page 105: Construction of distillation solvent recovery system

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V. CONCLUSIONS

The construction of the distillation portion of

the model of a nuclear fuels reprocessing plant has led

to the following conclusions:

1. The distillation column, condenser, reboiler,

feed heater, auxiliary heat exchangers, tanks, rotameters,

control valves, and process piping have been installed;

and preliminary testing has indicated that thi~ equip­

ment will function properly.

2. The process instruments with the necessary

pneumatic lines, regulation equipmen~, and air compressor

have been installed. This _equipm~nt is _now reasonably

free from air leaks and is ready for operational checks.

3o · Theoretical material and energy balances have

indicated that, at a reflux ratio of 1o25 and using a

reboiler and six ideal plates, 0.25 gallons .of feed at

the bubble point and consisting of 20o0 mole·per cent

methanol and 80.0 mole per cent water can be separated

into the following:

a. A distillate product consisting of

83.3 mole per cent methanol and 16.7 mole per

cent water.

b. A bottoms pr_oduct consisting of ·1 .o

mole per cent methanol and 99.0 mole per cent

water.

Page 106: Construction of distillation solvent recovery system

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4. The analytical instruments have been calibra­

ted and have been used to analyze .unknown samples of

methanol-water mixtures. The analytical instruments

consist of the following items of equipment:

ao A Westphal balance for determining the

specific gravity of the sample.

b. A dipping refractometer for determina­

tion of the index of refraction of the sample·.

c. A gas-liquid chromatograph for both

qualitative and quantitative analysis of the sample.

Page 107: Construction of distillation solvent recovery system

-98-

VI. SUMMARY

The Department of Chemical Engineering of the

University of Missouri School of Mines and Metallurgy,

Rolla, Missouri, received a grant f~om the Atomic Energy

Commission for the construction of a model of a nuclear

fuels reprocessing plant. The construction of a complete­

ly nonhazardous system has now been completed. The system

consists of an extraction unit· and a distillation unit . .

which can be operated either concurrent+Y or separatelyo .

The ternary liquid system water-methanol-trichloroethyl­

ene has been designated for use in the unit. Usi.ng the

principle of differential solubility, me~ha~ol is to be

extracted by water from a methanol-trichloroethylene

mixture in the extraction unit. The meth~ol-water mix-

ture thus obtained as the extract stream is then separated

in the distillation unit because of differential vapor

pressure. The system was constructed as an instructional

~id for students of nuclear ·and chemical engineering

rather than as a research tool.

The distillation unit consists of a s-ix-inch,

glass, bubble-cap.column and accessory equipment. The

feed plate, the rate and condition·of the feed, the re­

flux ratio, the top and bottom.column temperatures; and,

to a certain degree, the column· pressure can all be

Page 108: Construction of distillation solvent recovery system

-99-

s·elected as required to illustrate their effect on the

operation of the unit.

The distillation unit was instrumented with both

process and analytical instruments. The process i~stru­

ments serve the · dual purpose of controlling the distil­

lation process and providing a record of the c9nditions

of temperature, pressure, and flow throughout the system.

The analytical instruments can be used to determine .the

composition of the feed stream, of the top and bottom

product, and of the material on each plate of the column.

The primary objective in the design and construc­

tion of the distillat~on equipment was to provide maxi~

mum instructional benefit. This goal has been attained

in that:

1. The glass column allows visual understanding

of internal operations· and phenomena.

2. Versatility incorporated into the unit allows . .

control of the operating variables, making possible obser-

vation of the effect of these variables on the operat'ion

of the unit.

3. Instrumentation employed within the system

allo~s practical experience in the use and mode of opera­

tion of the process and analytical instrumentso

Page 109: Construction of distillation solvent recovery system

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VII. APPENDICES

The nomenclature used in the thesis is listed

in Appendix A.

Page 110: Construction of distillation solvent recovery system

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Appendix .A..

Nomenclature

The symbols used in this thesis are defined as

follows:

B Bottom product, lb-mole per hr

D Overhead product, lb-mole per hr

F Feed, lb-mole per hr

1 Specific enthalpy, Btu per lb; i _B, of bottom product; in, of over~ead product; iy, of v_apor from top plate; 113, of bottom product, corrected for heat effect qr; in, of over­head product, corrected for heat effect_ -qc

q Rate of heat flow, Btu per hr; qr, . heat· added -a~ rebo1ler; -qc, heat rejected at condenser

R Reflux ratio; Rn= L/D

x Mole or .mass fraction of component A in liquid; xB, in.bottom product! xn, in over­head product; XF, in feed to column

y Mole or mass fraction of component A in vapor; YB, in bottom product; Yn, in over­head product; YF, in feed to column .

Page 111: Construction of distillation solvent recovery system

-102-

VIII. BIBLIOGRAPHY

1. Albright, M.A.: Computer Gives Best ·Spiitter De­

sign, Petrol. Refiner, .21, Noo 12., 111 (1958).

2. Amundson, N. R. and A. J. Pontinen: Multicomponent

Distillation Calculations on a ·~arge Digital

Computer, Ind. Eng. ·. Chem., .5.Q., 730 ( 1958).

3. ---------------------------------- and J. N. Tierney: 38th National Meeting, Am. Inst. Chem. Engr. ·,

Salt Lake City, Utah, Sept • . 1958.

4. Ansell, L. s., H. Samuels and W. C. Frishe: Enthalpy

Concentration Chart for Methanol-Water Solutions,

Chem. Eng., 5..§., No. 4, 133 (1951).

5. American Institute of Chemical Engineers: 11Bubble­

Tray Design Manual," Scie1?,ce Press, Inc.; 1958.

6. Baranowski, R. ~.: Scope of the Pow~r Fuel Process­

ing Program, · "Proceedings of t~e AEC Symposium . for Chemical Processing.of Irradiated Fuels,u

held at Richland, Wash., Oct. 20 and 21, 1959,

p. 14. Office of Technical Services, pepartment

of Commerce, Washington 25, D. C., 1960.

7. Blanco, R. E.: Dissolution and Feed Adjustment,

ttsymposium on the Reprocessing of Irradiated

Fuels, 11 held at Brussels, Belgium, May 20-25,

1957, pp. 22-44. Technical Information Service

Extension, Oak Ridge,. Tenn., 1957.

Page 112: Construction of distillation solvent recovery system

--103--

8. ibid, pp. 30-31.

9. Bowman, F. E.: Solvent Extraction, "Materials for

Nuclear ~eactors" (B. Kopelman, Editor), PPo 305-

12. McGraw-Hill Book Co., Inc., New.York, N. Y.,

1959.

10. Brown, Go G. and associates: 11Unit Operations," . .

pp. 322-397. John Wiley & Son~, Inc., New York,

N. Y., 1950. 1 ed •.

11. Bruce, F. R., et al: 0 Progress.in Nuclear Energy, . Series III, Process .. Chemistry, 11 pp. 161-258-•

..

McGraw-Hill Book Co., Inc., New York, N. Y., 1956.

12. ibid, pp. 259-288.

13. ibid, pp. 289-341.

14. Callihan, A. D.~ J. W. Morfitt and J. T. Thomas:

Small Thermal Homogeneous Critical ·Assemblies, 11Proceedings of the Inter. Conf. on the Peaceful

Uses of Ato.mic Energy, I' 5., pp. 145-55. United

Nations Publications, New York, N. Y., 1956.

15. Canjar, L. N., H.B. Ford ahd R. T. Sebulsky: Pre­

dicting V-L Equilibrium Data, Petrol. Refiner, ·

.2.Q., No. 10, 135 ( 1957).

16·. Carr, c. and J. A. Riddick: Physical Properties of

Methanol Water System, Ind. Eng. Chem., 12., 693

(1951).

170 Chemical Processing of Reactor Fuel Elements at the

Idaho Chemical Proc~ssing Plant, 11 C~em1cal Pro­

cessing and Equipment, 11 p. 3 • . United States

Page 113: Construction of distillation solvent recovery system

-l0-4-

Atomic Energy Commission~ McGraw-Hill Book·

Co., Inc., New York, N. Y., 1955.

18. ibid, pp. ·-.-3~44.

19. Chiotti, P~ and A. F. Voigt: Pyrometallurgical

Processing, uProceedings of the Inter. Conf.

on the Peaceful Uses of Atomic Energy, 11 1.7.,

pp. 368-75. United Nations Pub.lications, New

York, N. Y., 1959 .•

20. Chu, J. C., S. L. Wang, S. L. Levy and R. ·Paul:

11Vapor-Liquid Equilibrium Data, 11 p. 420. J. · W. •.

Edwards, Inc., Ann .Arbor, Mich., 1956.

21. Cooper, V. R. and M. T •.. Walling, Jr.: Aqueous Sepa­

ration and. Decontamination Processes, "Proceed­

ings of the Inter. Conf. on the Peaceful Uses of

Atomic Energy, 11 U, pp. 291-323. United Nations

Publications., New York, N • . Y., 1959.

22. Cyclic Analysis. No Bar, Chem.· Engo, 66, No. 3, · 34

( 1959).

23. Drew, c. M.: Detectors, 0 Principles and Practice

of Gas Chromatography!• ·· (R. L. Pe_csok, Editor), ' . .

P. 116. John Wiley & Sons·, Inc., New York, N • . Y.,

1959.

24. Escher, E. E.: IR Process Gas ·chromatography, Chem.

Eng. , 2§., No. 1 5, 11 3-8 ( 19 59 ) •

25. Fard, M. R. : Design of Liquid-Liquid Extraction

System, P. 72, Unpublished M.Sc. T~esis, Library,

Page 114: Construction of distillation solvent recovery system

-.105-

Missouri School of Mines · and Metallurgy; Rolla,

Mo. ( 1958).

26. · Fisher-Gulf J::'artitioner, Catalogue No-. 1·1-130, p. 3.

Fisher ·scientific Co., Pittsburgh; Pa.

'Z(. Freilich, A.: Computers in Process Control, Chem.

Eng., §i, No. 6, 280-4 (1957).

28. Greenstadt, J., Y. Bard and B. Mors.e: Multicompo­

nent Distillation Calculation on the IBM 704,

Ind. Eng •. . Chem., ~' 1644 ( 1958).

29. 11Handbook of Organic Industrial Solvent.s, 11 pp. 25, . .

34,· 51, 60. National Association of Mutual Casu-

alty Companies, Chicago, Ill., 1958.

30. Here 1 s a More Effectiv? Support for Chromatography

of Polar Compounds, The Laboratory,~' No. 4,

1 1 8-9 ( 1 9 59 ) •

31. Higgins, E. J., J. W. Kellett and L. ·T. Ung: ·Engi-

neering Des.ign on a Computer, Ind·. Eng. Chem.,

5Q, 716 ( 1958).

· 32. Howe, J.P.: Reactor Fuel Metallurgy, 0 Proceedings . t

of the Inter. Conf. on the Peace·ful Uses of· Atomic

Energy, 11 2., p. 179. United Nations Puolications,

New York, N. Y., 1956.

33. Hurst, R., et al:. The Homogeneous Aqueous Reactor,

J. Brit. Nucl. Energy Conf., g, ·395-405 ( 1957).

34. "International Critical Tables," Il, p. 66. McGraw­

Hill Book Co., Inc., . New York, N. Yo., 1929.

Page 115: Construction of distillation solvent recovery system

---1.06-

35. James, A. T. and A. J.P. Martin: Gas-Liquid-Parti­

tion Chromatography: The Separation and Micro­

Estimati~n of Volatile Fatty Acids from ·Formic

Acid to Dodecanoic Acid, Biochem. : J., 5Q., 679

(1952).

36. Johnson, A. I. and c. w. Bowman: Can. J. Chern. Engr.,

.1§., 253 (1958) ~

37. Johnson, J. R. and C. E.. Curtis: T~chnology of uo2 and Th02, 11Procee.dings of the In-ter. Conf. on

the Peaceful Uses of Atomic Energy," 2., p. ·169.

United Nations Publications, New York, N. Y.,

1956.

38. -Kaufmann, A. R.: Fabrication of Uranium Alloys,

"Proce.edings of the· Inter. Conf. on the Peaceful

Uses of Atomic Energy, 11 2., p. 210. · United Na­

tions Public_ations, New York, N·_. · Y,,, · 1956~

39. Keulemans, A. I_. M.: -"Gas . Chromatogr.~phy, 11 p.· 9~. ·

Re~nhold Publishing Corp., New York, N. Y., 1957.

40. ibid, p. 55.

41-. ibid, p. 32.

42. Kling, H •. P. and B. Kopelman: Ceramic Fuels, "Mate-,.

rials for Nuclear Reactors 11 (B. Kopelman, Editor),

pp. 90-108. McGraw-Hill Book Co.; Inc., New York,

N. Y., 1959 •

43. Knight, H. S.: Mechanism of Separation, 11Principles

and Practice of Gas Chromatograp~y" (R. L. Pecsok,

Page 116: Construction of distillation solvent recovery system

-107-

Editor), pp. 21-8. John Wiley & Sons, _Inc.,

New Y~rk, N. Y., 1959.

44. Lawroski, s.: Non-Aqueou·s Processing - 1m In~roduc-.•

tion, "Symposi~ on the R~processing· . of Irradia­

ted Fuels, 11 held at Brussels, Belgium, May 20-

25, 1957, pp. 479-97. Te·chnical Information Ser~

vice Extension, Oak Ridge, Tenn., 1957.

45. ibid, p. 479 •

. 46. ibid, p. 480.

47 •.. ibid, p. 482.

48. Lyster, w. N., D.S. Billingsley, et al: 38th.Nat.

Meeting, Am. Inst. Chem. Engro ,: Salt Lake City,

Utah, Sept. 1958.

49. Maddox, R. N. : · Use Digital Comput.ers .as · ·nistillation

Column Design Aid, Petrol. Engr., 3.Q., No. 4, - 15-8

( 1958) 0

50. Martin, A. J.P. and R. L. -M. Synge: A New Form of

C~omatography Employing Two Liquid'Phases. I.

A Theory of Chromatography: II. Application of

the Microdetermination of the Higher Monoamino-

acids· in Proteins, Biochem. J., J.!2., 1358-68

(1941).

51. Martin·, F. s. and' G. L. Miles: 11 Chem1cal Processing

of Nuclear Fuels, 11 . pp. 3-13. Butterworths Scien­

tific Publications, London~ 1958.

Page 117: Construction of distillation solvent recovery system

52.

53.

54.

55.

56.

-1.08-

i .bid, p. 15.

ibid, pp •. 19-25.

ibid, p. 98. ·

ibid, pp. 223-231.

McCabe, W. L. and J. C. Smith: 11Unit Operations of

Chemical Engineering, u pp·. 665-755. McGraw-Hill

Book Co., Inc., New York, N. Y., 1956.

57. McKay, H. A. C. and c. M. Nicholls: Criticality in

Producing Fissile Materials: ttProceedings of the . .

Inter. Conf. on the Peaceful Uses of Atomic Ener-

gy,u U, pp. 311-4. United Nations Publications,

New York, No Y. ,. 1956 •.

58. Messner, A. E., D. M. Rosie and P.A. Argabright:

Correlation of Thermal Conduct.ivity Gell Response

with Molecular Weight and Structure, Anal. Chem.,

.ll, 230-3 (1959).

59. 0 Nialk Trichloroethylene," p. 9. Niagara Alkali Com-

pany, 1953.

60. Okenfuss, R.H.: Redesign and Construction of Ro­

tating Di~c Contaotor, p. 108, Unpublished M. Sc.

Thesis, Library, Missouri School of Mines and

Metallurgy, Rolla, Mo. · (1960).

61. Patton, H. W.: Fundamental Principles, 11Principles

and Practice of Gas Chromatography!' (R. L~ Pecsok,

Editor), pp. 8-20. John Wiley & Sons, New York,

N. Y., 1959.

62. (Seep. 112).

Page 118: Construction of distillation solvent recovery system

-109-

63. Puyear, D. E.: Design of Distillation Solvent Re­

covery System, Unpublished M. Seo Thesis·, Li­

brary, Missouri School of Mines and Metallurgy,

Rolla, Mo~ (1958).

64. ibid, p. 65.

65. ibid, pp. 83-87.

66. ibid, pp. 93-107.

67. ibid, pp. 1 33-1 34.

68. Raiklen, H. and W. Go Lidman: Cladding and Bonding

Techniques, .. Materials for Nuclear Reactors 1.1

(B. Kopelman, Editor), pp. 157-76. McGraw-Hill

Book Co., Inc., .New York, N. _Y., 19590

69. Richards, R. B.: Aque·ous Reprocessing - An Introduc­

tion, "Symposium on the Reprocessing of Irradia~ . ted Fuels," held at Brussels, B~lgium, May 20-

25, 1957, pp. 3-21. Technical Information Ser­

vice Extension, Oak Ridge, Tenn., 1957.

70. Robinson, c. S. and E. -R. Gilliland: "Elements of . Fractional Distillation," McGraw-Hill Book Co.,

Inc.,· New York, N. Y., 1950. 4 ·ed.

71. Rosenbrook, H. H.: . Calculation of the Transient

Behavior of Distillation Columns, Brit. Chem.

Engr., l, 364:.7, 432-5, 491-4 (1958) • .

-72. Rose, A. and R. F. Sweeny: Ternary Batch Distilla­

tion Calculation for Rectification of Naphtha-

lene Tar Acid Oil, Ind. Eng. ~he~., -5.Q_, 1687 (1958).

Page 119: Construction of distillation solvent recovery system

-110-

73. Rothlin, S., J. L. Crutzen and G. R. · Schultze:

Gleic~gewichte Flussiz/flussiz in Einegen T~r~

naren System und Gegenstrom-Extrakin in Einem

Horizontalen Rohr, Chemie_. Ing. Techn., ~' ?11-

9 (1957). (in German) .

7 4. Saller, H. A.: . Aluminum-Uranium Alloys, 11Proceed­

ings of the Inter. Conf. on the Peaceful Uses of

Atomic Energy·, u 2., ·p. 214. United ~ations Pub­

lications, New York, N. Y., · 1956.

75. Sargent, R. W • . H.: Trans. Inst. Chem. Engr. (London),

.22., 20 1 - 1 4 ( 1 9 58 ) •

76. Schumar, ·J. R.: Reactor Fuel El~ments, Scientific

American, 200, No. 2, 37 (1959).

77 • . Steunenberg, R. K. and R. _c. Vogel: Survey of Fluo~

ride Volatility Pro_cesses, 11Proceedings of the .. Inter. Conf~ on the Peaqeful Uses of Atomic

Energy, 11 11., pp. 438-51 • . United.Nations. Publi­

cations, New York, N. Y.j 1959~ ·

78. 11 Symposium on the Reprocessing of Irradiated Fuels, 11 .

held .at Brussels, _Belgium, May 20-25, 1957, Books

1, 2,' and . 3 •. Technical . Information Service ·Ex­

tension, Oalc Ridge, Tenn., 1957.

79. Weissberger, A.: · "Technique of Organic Chemistry, 11

4. Interscience Publishers, Inc., New York,

N. Yo, 1951.

Page 120: Construction of distillation solvent recovery system

-1·1.1-

80. Welch, H. T.: Pressure Drop Through Bubble Caps,

Petr~l. Refiner, 21., No. 8, 127 (1958). ·

81. Whitman, c. 'I.: Fuel Reprocessing, 11Materials for .. Nuclear Reactor.a" (B. Kopelman, Editor), pp.

337-4o. McGraw-Hill Book Company, Inc., New

York, N. · Y., 1959.

82. · Wing, R.H.: Rethink Your Distilla~ion Design,

Chem. Eng., .2§., No~ 21, 185-8 (1959) •

. 83. Winn, R. W.: . New Relative Volatility Method for

Distillation Calculations, Petrol. Refiner,.

:fl.·, No. 5, 215-8 (1958) • .

84. Witt, R·.: Th~rium, . 11Materials f<;>r Nuclear Reactors II . (B. Kopelman, Editor), pp. 45-58. McGraw-Hill

Book Company, Inc., New York, .N. Y., 1959.

85. · Wymer, R. G. and D. L. _Foster: Nuclear Reactor Fuel

Dissolution~· "Progress in Nuclear Energy, S~ries . III, Process Chemistrytt (F • . R. Bruce, et ~l., .

Editors), pp. 85-96. McGraw-Hill Book Company,

Inc., New York, N. Y., 1956.·

86. u. s. Atomic ~argy Commission: Reactor Fuel Pro­

cessing, land g (1958).

87. u. s. Atomic Energy Commission: Reactor Fuel Pro­

cessing, l, No. 1 , 7 ( 19 58) •

88. u. s. Atomic Ene~gy Commission: Reactor Fuel Pro­

cessing,!, No. 3, 3 (1958).

Page 121: Construction of distillation solvent recovery system

-112-

89. Zuiderway, F. J. and A. Harmons: Chem.~ Eng. Sci.,

2., 89 ( 1. 9 58 ) •

Addenda

90. McCabe, W. L. and J. c. Smith: 11Uni t Operations of

91 0

920

93.

. Chemical Engineering," p. 6860 . McGraw-Hill Boolt

Co., Inc., New York, N. Y. ,· 19560

ibid, p. 716.

ibid, P• 719.

Ponchon, M.: Tech. Moderne, u· . ' 20 ( 1921) 0

. Foust, A. S. and associates: "Principles of Unit

Operations," p. 49. John W!°ley & Sons, New York,

N. Yo, 1960.

94. Savarit, R.: Arts et· Metiers, 65ff ( 1-922).

Foust, A. s. and associates: "Principles of .Unit

Operations," p. 49. John Wiley·~- Sons, New York,

N. Y. , 1 9 60 • · - ·

62 0 Pecsok, R. L.: Analytical· Methods, '~Principles and . Practice in Gas Chromatography'~ (Ro L. Pecsok,

Editor), pp. 142-143. John Wiley & Sons, Inc.,

New York, N. Y., 1959.

Page 122: Construction of distillation solvent recovery system

-113-

IX. ACKNOWLEDGEMENTS

The author of this thesis wishes to thank Dr.

Dudley Thompson, Major Adviser for this project, for his

patient and understanding assistance in the completion

of this research project.

Mr. R.H. Okenfuss and Mr. c. J. Vetter, who were

responsible for the construction of the extraction por­

tion of the project, were of invaluable assistance in

coordinating their work with the work of the author.

The indebtedness of the author is gratefully acknowledged.

A special "thank youtt is extended to the under­

graduate students who put in many hours of labor on the

unit. while enrolled in Chemical Engineer~ng 300. Their

assistance in the construction· of the unit is . greatly

appreciated.

The author's wife, Lucene, has given noble service

in proof reading the draft and assisting in the compila­

tion of the final thesi·s. To her the author 1·s warmest

appreciation is extended~

The services, in the fabrication of equipment, of

Mr. Russell Welch and Mr. Elmer Giddens of the Chemical

Engineering Staff·are genuinely appreciated.

The assistance of the members of the staff and

graduate students of the Chemical Engineering Department

is appreciated and hereby acknowledged.

Page 123: Construction of distillation solvent recovery system

-114-

The author is also indebted to the Atomic Ene_rgy

Commission for the funds which made this project po~si­

ble and · to Mr. D. E. Puyear and Mr.· Mo R. Fard for the

original design work on the unit.

Page 124: Construction of distillation solvent recovery system

X. VITA

The author of this thesis was born on October 16,

1935, in West Plains, Missouri. He received his elemen­

tary and high school educations in the West Plains public

school system. His high school education was completed

in May, 1953. He entereo.· Westminster College in Fulton,

Missouri", in September, 1953, and was enrolled during the

scho9l years 1953-54 and 1954-55. He attended.summer

school at the University of Colorado in Boulder, Colorado,

during the summer of 1954. At thi~ time~ he transferred

to the ~niversity of Missouri School of Mines . and Metal­

lurgy in Rolla, Missourio He was enrolled during the

Page 125: Construction of distillation solvent recovery system

-116- -

school years 1955~56 and 1956-57. He accepted a job

with Columbia-South~rn Chemical Corporation, Corpus ·

Christi, Texas, .~s a Project Engineer in the Development

Departm~nt in June, 1957, and remained. with them until

February, 1958. _During the summer of 1957 he was·e~­

rolled in the night·school ·of Del Mar University, Corpus

Christi. He then returned . to the University of. ·Missouri

School of Mines and Metallurgy and completed the require­

ments for a Bachelor of Science Degree in Chemical Engi­

neering in June, 1958.

Upon graduation, the author worked for Oolumbia­

Southern Chemical Corporation during the summer of 1958.

He returned to the Univers.ity of Missou~i S_chool of Mines

and Metallurgy in September, 1958, to_ begin work -on the

requirements for the Master . of Sci.ence Degree in Chemical

Engineering. He served as a Graduate Assistant in Chem~

ical Engineering from September, 1958, to-August, 1959;

as an Assistant Instructor in qhemical Eng~neering from

September, 1959, to January, 1960; and· as an Instructor

in Chemical Engineeri~g from February, 1960 to June, 1960 •

...... / (/