training session on water treatment

8/12/2019 Training Session on Water Treatment

1/141


2/141

2

COMMONLY USED TERMS IN WATER TREATMENT

1. OBR: OUTPUT BETWEEN TWO SUCCESSIVE REGENERATIONS.

2. TDS: TOTAL DISSOLVED SOLIDS

3. TSS: TOTAL SUSPENDED SOLIDS

4. HARDNESS: TOTAL OF CALCIUM & MAGNESIUM

5. FLOW RATE: VOLUME IN M3/HR REQUIRED TO BE TREATED.

6. CATIONS: POSITIVELY CHARGED IONS IN WATER.

7. ANIONS: NEGATIVELY CHARGED IONS IN WATER.

8. DM PLANT: DEIONISATION / DEMINERALIZATION PLANT.

9. EXCHANGE CAPACITY: THE CAPACITY OF RESIN TO REMOVE THE

DISSOLVED IMPURITIES.

10. REGENERATION: THE RECHARGING OF ION EXCHANGE RESIN BY

USE OF ACID OR CAUSTIC.


3/141

3

COMMONLY USED TERMS IN W TER TRE TMENT

1. RO PLANT: REVERSE OSMOSIS PLANT.

2. GFD: GALLONS OF WATER FROM RO PLANT PER DAY PER FT

SQUARE AREA OF RO MEMBRANE.

3. FOULANTS: THE ELEMENTS IN WATER THAT IS LIKELY TO CAUSE

DAMAGE TO THE TREATMENT EQUIPMENT (RESIN/MEMBRANE).

4. CONDUCTIVITY: THE ELECTRONIC MEASUREMENT OF DISSOLVED

IONS.

5. CLEANING: THE CHEMICAL CLEANING OF RO MEMBRANE TO

RESTORE THE OPERATING CONDITION.

6. M3: 1000 LITRES.

7. GALLONS: US GALLONS 3.785 LITRES.


4/141

4

RAW WATER APPRAISAL

SOURCES LIKE BORE WELL,SHALLOWWELL,RIVER,LAKE,SEA,MUNICIPAL.

DIFFERENT SOURCES HAVE DIFFERENTCHARACTERISTICS.

IONIC IMPURITIES VARY FROM SOURCETO SOURCE. TWO WELLS IN SAMEPREMISES SHALL BE DIFFERENT.

IMPURITIES: SOLUBLE,NON-SOLUBLE,ORGANIC ORIGIN.

IMPORTANT TO UNDERSTAND RAWWATER.


5/141

5

RAW WATER SOURCES & THEIR PECULIARITIES

SOURCE DISSOLVEDIMPURITIES

SUSPENDEDIMPURITIES

ORGANICIMPURITIES

DEEP WELLWATER

HIGH LOW LOW

SHALLOW WELL

WATER

MODERATE LOW MODERATE

RIVER LOW HIGH -SEASONAL

MODERATE

LAKE MODERATE MODERATE HIGH

SEA V. HIGH MODERATE MODERATE

MUNICIPAL LOW LOW LOW

EFFLUENT HIGH HIGH HIGH

NOTE: THIS IS TO GIVE THE GENERAL IDEA. THERE CAN BE EXCEPTIONS.


6/141


7/141

7

CLASSIFICATION OF RAW WATER ANALYSIS INVARIOUS CATEGORIES

NONDISSOLVEDIMPURITY

TSS, TURBIDITY, COLLOIDALSILICA, COLOR, SMELL

DISSOLVEDIMPURITY

TDS, CALCIUM, MAGNESIUM,SODIUM, SILICA, CHLORIDES,

SULPHATES, NITRATES,ALKALINITY, TOTAL HARDNESS

ORGANICIMPURITY

COD, BOD, COLOR, SMELL

TOTALHARDNESS

CALCIUM, MAGNESIUM

EACH OF THESE REQUIRES DIFFERENTTREATMENT FOR REMOVAL.


8/141

8

WATER TREATMENT METHODS AVAILABLE & WHICH IMPURITYIT CAN REMOVE.

TREATMENTMETHOD

IMPURITIES REMOVED

TUBE SETTLER &CLARIFIERS

TSS, TURBIDITY, COLLOIDAL SILICA

FILTERS TSS, TURBIDITY

SOFTENER TOTAL HARDNESS

DM PLANTS TOTAL HARDNESS, TOTAL DISSOLVEDSOLIDS, CALCIUM, MAGNESIUM, SILICA,ALKALINITY, CHLORIDES, SULPHATES

RO PLANTS TOTAL HARDNESS, TOTAL DISSOLVEDSOLIDS, CALCIUM, MAGNESIUM, SILICA,ALKALINITY, CHLORIDES, SULPHATES

CHLORINATION BOD & COD

ACTIVATEDCARBON FILTER

FREE CHLORINE, COD, BOD, COLOR, SMELL

DEGASSER TOWER ALKALINITY


9/141

9

WHICH METHOD OF TREATMENT

TO CHOOSE ? RAW WATER ( INLET ) PARAMETERS

TREATED WATER QUALITY REQUIRED

APPLICATION OF TREATED WATER

ECONOMIC OPERATIONAL COST


10/141

10

FILTERS: Diameter (Mtrs.)=

(FLOW RATE M 3 /HR / VELOCITY M/HR)0.785

HEIGHT OF FILTERS IS USUALLY FIXED AT 1500 MM OR2000 MM.

SOFTENER: REQUIRES SOME CALCULATIONS ASFOLLOWS:FLOW RATE IN M3/HR = FDURATION BETWEEN REGENERATION HRS = THENCE OUTPUT BETWEEN REGENERATION= F X T

REFER TO SOFTENER RESIN GRAPHS TO GETREGENERATION LEVEL = SAY 150 G/LEXCHANGE CAPACITY = SAY @ 50

HENCE QUANTITY OF RESIN REQUIRED IN SOFTENER (

LITRES):

= OUTPUT BETWEEN REGENERATION NET EXCHANGE CAPACITY

SELECT THE SOFTENER WITH THE NEAREST RESINQUANTITY FROM SOFTNER CHART.


11/141


12/141

12

SIZING

RO PLANTS: REQUIRES DETAILED CALCULATIONS.

STEPS AS FOLLOWS:

DATA COLLECTION:FLOW RATE IN M3/HRDETAILED CATION & ANIONIC ANALYSISHOURS OF OPERATIONSQUALITY OF WATER REQUIRED

DESIGN STEPS:RO PROJECTION FROM SOFTWAREDECIDE ON THE OVERALL SCHEMEEQUIPMENT SIZINGCHEMICAL CONSUMPTION SIZING

CALCULATIONS


13/141

13

COMMONLY OCCURING PROBLEMS IN A WATERTREATMENT SYSTEM

1. REDUCTION IN FLOW RATES

2. REDUCTION IN THE OUTPUT BETWEEN REGENERATION

3.

QUALITY DETERIORATION

4. LEAKAGES & OTHER MECHANICAL PROBLEMS

5. PROBLEMS RELATING TO INSTRUMENTS & CONTROL

6. CHOCKING OF FILTERS & MEDIA LEADING TO FREQUENTBACKWASH.

7. HIGH PRESSURE DROP


14/141

14

-

IT IS ESSENTIAL TOUNDERSTAND THE

CONSTRUCTIONAL DETAILS &OPERATING STEPS IN ORDERTO SOLVE THE PROBLEM


15/141

15

EQUIPMENT DESCRIPTION

FOR FILTERS PRESSURE VESSEL INLET DISTRIBUTION SYSTEM

BOTTM COLLECTION SYSTEM SUPPORT MEDIA FILTRATION MEDIA FRONTAL PIPEWORK

SERVICE OPERATION BACKWASH OPERATION


16/141


17/141

17


18/141

18


19/141


20/141

20


21/141

21


22/141


23/141


24/141


25/141

25


26/141

26


27/141

27


28/141

28


29/141

29


30/141

30


31/141

31


32/141

32


33/141

33


34/141

34


35/141

35


36/141

36


37/141

37


38/141


39/141


40/141

40


41/141

41


42/141

42


43/141

43


44/141

44


45/141

45


46/141

46

EQUIPMENT DESCRIPTION

FOR SOFTENER PRESSURE VESSEL INLET DISTRIBUTION SYSTEM BOTTM COLLECTION SYSTEM STRAINERS SOFTENING RESIN REGERATION SOLUTION TANK FRONTAL PIPEWORK

SERVICE OPERATION BACKWASH OPERATION REGENERATION OPERATION


47/141

47


48/141

48


49/141

49


50/141


51/141

51


52/141

52


53/141

53


54/141

54


55/141

55

EQUIPMENT DESCRIPTIONFOR DM PLANTS

PRESSURE VESSEL INLET DISTRIBUTION SYSTEM BOTTM COLLECTION SYSTEM STRAINERS CATION & ANION RESIN REGERATION SOLUTION TANK FRONTAL PIPEWORK

SERVICE OPERATION BACKWASH OPERATION REGENERATION OPERATION


56/141

56


57/141

57


58/141

58


59/141

59


60/141

60


61/141

61


62/141

62


63/141

63


64/141

64


65/141

65

DM REGENERATION SEQUENCE

1 TO REMOVE ACCUMULATED FOREIGN

MATERIALS AND RESIN DUST.

2 TO INJECT ACID OR ALKALI TO CONVERT RESIN

IN TO ACTIVATED FORM.

3 TO REMOVE EXCESS ACID / ALKALI FROM RESIN .

OBJECTIVES OF REGENERATION


66/141

66

STEPS OF REGENERATION

1 BACKWASH.

2 REGENERATION INJECTION.

3 SLOW RINSE.

4 FAST RINSE


67/141

67

BACKWASH

- RESIN IS FLUIDISED TO 40 TO 50 %BED EXPANSION.

- ACCUMULATED DIRT, RESIN FINESREMOVAL.

- RESIN BED IS HYDRAULICALLY

CLASSIFIED.


68/141

68

REGENERATION INJECTION .

- ACID OR ALKALI IS USED SAC : HCL OR H 2 SO4

WBA : NaOH

SBA : NaOH- CONCENTRATION

WEAK RESINS : 0.5 % - 2.5%

STRONG RESINS : 3.0 % - 5%- TIME TO BE SUFFICIENT FOR

ADEQUATE CONTACT .


69/141

69

REGENERATION LEVEL

- KGS OF 100% REGENERANTINJECTED FOR EVERY M 3 OF RESINS.

- IMPORTANT FOR ONLY STRONG

RESINS ( SAC & SBA)

- R/L RANGE IS 30-160 KG/M 3


70/141

70

REGENERATION QUANTITY

- FOR STRONG RESINS.RESIN VOL. (M 3 ) X REGENERATION

LEVEL (KG/M 3 ).

- FOR WEAK RESINS.

WORK DONE BY RESIN.=

IONIC LOAD ( As CaCO 3) X OBR M3

1000 X 1.25 OR 1.37 ( TO CONCERT FROM CaCO3 TO EQUIVALENT)

X 115


71/141

71

TYPES OF REGENERATION

SEQUENCES .

- CO-FLOW- COUNTER FLOW- DOWN FLOW, PACKED- UPFLOW , CONVENTIONAL


72/141

72

FAST RINSE

- PURPOSE IS TO REMOVE EXCESS

REGENERANT FROM RESIN BED.

SERVICE INLET WATER IS USED.FAST RINSE IS CONTINUED

TILL DISIRED OUTLET QUALITY IS

OBTAINED


73/141

73

CO FLOW REGENERATION.

REGENERANTINLET

SERVICEINLET

REGENERANTOUTLET.

SERVICEOUTLET


74/141

74

COUTER REGENERATIONDOWN FLOW

REGENERANTINLET

SERVICEOUTLET

REGENERANTOUTLET.

SERVICEINLET

COFLOW REGENERATION


75/141

75

COFLOW REGENERATION

- LEAKAGE OF IONS IS HIGH

- TREATED WATER QUALITY IS NOT CONSISTENT.

THROUGH OUT CYCLE.

- REQUIRES VERY LARGE QUANTITY OF REGENERANT

FOR QUALITY IMPROVEMENTS.

- REGENERATION EFFICIENCY IS LOWER ( 30-45%)

COUNTER REGENERATION


76/141

76


( DOWNFLOW)- HAS ALL ADVANTAGES OF UPFLOW COUNTER

CURRENT REGENERATION.

- UP FLOW COUNTER CURRENT REGENERATION.

- BACKWASH IS NOT POSSIBLE BECAUSE OF LACK

OF FREE BOARD.

- FEED WATER TURBIDIY SHOULD BE LOW ( < 1 NTU )



77/141

77


- LEAKAGE OF IONS IS LOW.

- TREATED WATER QUALITY IS CONSISTENT

THROUGHT THE RUN.

- REDUCED REGENERANT QUANTITY ALSO

PRODUCES IMPROVED QUALITY.

- REGENERATION EFFICIENCY IS HIGHER (80-90%)


78/141

DV NT GES OF REVERSE OSMOSIS SYSTEM OVER


79/141

79

DM

We would like to propose an RO based treatment scheme inplace of DM based system. We would like to highlight that theR.O. based treatment system shall be more beneficial in

terms of following parameters :

1. Very less operating cost. (Enclosed an annexure ontypical operating cost calculations for DM & RO)

2. Less chemical handling and storage.

3. Very less operational needs thus the manual Reverse

Osmosis Plant shall suffice in place of an automatic DMPlant.

4. Less civil work.

5. Less area requirements.

6. Reverse Osmosis system can take the marginalvariations in feed water quality without affecting thetreated water parameters.

7. No need for any neutralisation pit. The RO reject & MBregeneration effluents can be directly taken to guardpond.


80/141

REVERSE OSMOSIS RO )

TOPICS :

- PRINCIPLES OF RO.

- PRETREATMENT FOR RO.

- OPERATION & MAINTAINANCE.

- TROUBLE SHOOTING.

- CASE STUDIES & DISCUSSIONS.


81/141

PRINCIPLES OF RO

- RO BASICS.

- TYPICAL RO ARANGEMENT - OPERATING ARANGEMENT.

- DESIGN PARAMETERS. - SELECTION OF RO MODEL.

Reverse Osmosis


82/141

Reverse Osmosis

P >

Reversing osmotic flow by applying a pressurein excess of the osmotic pressure

P

DILUTESOLUTION

CONCENTRATEDSOLUTION


83/141

TYPICAL RO ARRANGEMENT.

PRETREATMENT RO POST TREAT


84/141

Block Diagram of RO

(PERMEATE )

PRODUCTWATER

REJECTWATER

(CONCENTRATE)

HIGH

PRESSURHEPUMP

SALTWATER


85/141


86/141

OPERATING PARAMETERS

FEED

PERMEATE7.5 M3/HR50 PPM

CONCENTRATE2.5 M3/HR

3850 PPM

RECOVERY = PERMEATE FLOW = 0.75 OR 75 %

FEED FLOW

10 M3/HR

1000 PPM

SALT PASSAGE = PERMEATE TDSFEED TDS

= 0.05 OR 5 %SALT REJECTION = 100 - SALT PASSAGE

= 95 %.


87/141

OPERATING PARAMETERS

FEED PERMEATE 7.5m3/hr.OF 50 PPM AT 5 PSI

CONCENTRATE 2.5 M3/HROF 3850 PPM AT 215 PSI

RECOVERY = PERMEATE FLOW = 0.75 OR 75 %

FEED FLOW10 M3/HR

1000 PPM230 PSI

SALT PASSAGE = PERMEATE TDSFEED TDS

= 0.05 OR 5 %SALT REJECTION = 100 - SALT PASSAGE

= 95 %.

P = FEED PR - CONC. PR= 230 - 215 = 15 PSI

DESIGN PARAMETERS


88/141

FLUX - GFD

- L/M 2H

GFD = 0.59 * L / M 2 H

GFD = 8-10 FOR WASTE WATER &

SEAWATER.

< 14 FOR SURFACE

< 18 FOR WELL WATER

< 25 FOR PERMEATE

DESIGN PARAMETERS


89/141

BETA FACTOR = MAXIMUM

1.16 FOR LAST ELEMENT ATCONCENTRATE SIDE

T i l A li ti


90/141

Typical ApplicationsOf

Reverse Osmosis

Industrial process water Production of potable water Food processing Waste treatment


91/141

Membrane manufactures Dow Filmtec.,U.S.A. Fluid systems U.S.A.

Hydranautics U.S.A. Osmonics inc U.S.A. Trisep USA. Saehan KOREA


92/141


93/141

CROSS SECTION OF THIN FILM

COMPOSITE MEMBRANE

SEMIPERMEABLEMEMBRANE

POROUSSUPPORT

BACKINGMATERIAL

THIN-FILM COMPOSITE MEMBRANES


94/141

40 micrometer

120 micrometer

0.2 micrometerPolyamide

Polysulfone

UltrathinBarrier Layer

MicroporousPolysulfone

ReinforcingFabric

THIN FILM COMPOSITE MEMBRANES

Membrane Assembly


95/141

Membrane Assembly

End cap

In board connec tor

Outer bord

connector

Feed tube

o rings


96/141

Reverse OsmosisMembranes - Types

Cellulose Acetate

Thin Film Composite Polysulfones


97/141

THIN FILM COMPOSITE

MEMBRANE CHARACTERISTICS Lower Operating Pressure

High Salt Rejection Available for Sea Water Stable to pH 11 Sensitive to Oxidants

Benefits of R O


98/141

Benefits of R.O.High recovery rates.Predictable water quality--regardless ofTDS content.Simple operation and control.Limited chemical problems.No daily regeneration hassels.Can be skid mounted,hence less space.Very few components for maintenance.Less operator attention


99/141


100/141

Source of Water

Surface water Lake or Pond

River Well Water

Shallow well

Deep Well Treated Effluent


101/141

Silt Density Index - SDI

How to measure SDI Quanitifies particles of range 0.45 to 5

microns Dual media removes upto 50 microns. Multimedia with garnet removes down to

25 microns.


102/141

Feed Water Analysis

Need to know the trend in the increase. Onsite pH. Appearance of water as drawn Organics. Biological activity of water.

RO System Design


103/141

Temperature (Max, Min & Average) Chlorine Residual Turbidity Suspended solids Color. Silt Density Index pH colliform Count (bacteria) Total Plate Count Calcium Magnesium Pottashium Iron

y g

ManganeseBariumStrontiumChloriteSulfateNitrateAmmoniaPhosphateFluorideSilicaTotal Dissolved SolidsHydrogen SulfateCarbon Di Oxide

Parameters required for designing :

Note : Variation in these parameters should be noted and odours, traces of industrial pollutant,clay, sand, rust, or other unusual characteristics should be described.


104/141

Reverse Osmosis

System Design


105/141

MEMBRANE SELECTION


106/141

MEMBRANE SELECTIONBASIS

Application or end use Quality Desired Water Temperature

4-2-1 Array


107/141

y

Feed

2000mg/L173 gpm

89 mg/L98 gpm

239 mg/L42 gpm

638 mg/L16 gpm

Concentrate18,211

mg/L17 gpm

8231 HR, 90%

Recovery

Permeate187 mg/L156 gpm

1st Bank

2nd Bank 3rd Bank

RO S


108/141

RO System components

The basic expanded design of a single systemincludes the following:

Raw water feed pump to supply water to the pretreatment

Pre treatment system for Turbidity,TSS,Colloidalparticles & Organic matter.

Cartridge filter to remove micron size particle tocontrol the SDI( Silt density index) of feed water

Anti scalant dosing system. High pressure pump&feed control valve to pressurize

the feed water. Membranes housed in Pressure tubes. -----continued.,


109/141

A reject control valve to control the recovery of the ROsystem.Askid to mount to all mechanical equipment .Flow indicators to measure permeate and rejectflowrates.Pressure gauges for monitoring the differentialpressures across the RO feed, reject and intermediatestages.Conductivity & pH meter for measuring the quality ofthe permeate water.And other necessary instruments for monitoring easyoperation and critical parameters.A cleaning system consisting of Tank,CF,Pump andnecessary instruments.

PRETREATMENT FOR


110/141

PRETREATMENT FORRO PLANT

CHLORINATION.

USE OF SODIUM HIPO CHLORITE.

- TO GET MAXIMUM FRC 0.5 PPM AT THE POINT OF

BISULPHITE DOSING.- EFFECTIVE REACTION TIME 20 - 30 MIN.

PRETREATMENT FOR


111/141


DE - CHLORINATION

- TOLERANCE < 1 PPM MAX

- ACITIVATED CARBON FILTER.

- BISULPHITE DOSING WITH ORP METER.

- 1 PPM OF F.R.C REQUIRES 1.46 PPM OF NaHSO3

.

PRETREATMENT FOR


112/141


pH

- ACID DOSING / ANTISCALENT CHEMICALS.

- HCL / MAXTREAT CHEMICALS. - AS PER PROJECTION.


113/141

PRETREATMENT FOR RO PLANT

OIL & GREASE & COD / BOD

REQUIREMENT - NIL

- IF IT IS PRESENT- REF : MATTER TO H.O. PEG.

IRON & Mn - LESS THAN 0.1

PRETREATMENT FOR


114/141


REMOVAL METHODS FOR Fe (Iron)

1. BY MnO 2 FILTER UP TO 1 PPM.

2. OXIDATION BY AIR, FOLLOWED BY FILTERATION -MORE THAN 3 PPM

3. OXIDATION BY CHLORINATION - UP TO 2 PPM.

Reverse osmosis systemCleaning tank


115/141

Pretreatment

RO hydrablock

Cleaningsystem

Clarification

Coagulation

Filteration

De-chlorination

Dosing system

Cartridge filter

Membrances

Pressure tubes

HP pumps

Control pannel

Cleaning tank

Pump (SS)

Cartridge filter

DM plant

pH adjustment

Degassification

Posttreanment

Schematic diagram of RO unit for brackish water


116/141

Lime or lime - sodacoagulant aids

coagulation andsedimentation

Sandfilter

Activatedcarbon filter

Mn greensandfilter

S.H.M.P. Acid

High pressurepump

DESALATION SECTIONMembrane modulesProduct

water

Wastebrine

Polishingfilter

Operating Parameters


117/141

p g

.Feed PressureConcentrationpHTemperature

Permeate ConcentrationFlowPressure

Concentrate FlowPressureConcentration

S P fil


118/141

System Profile The System Profile is a measurement of the

permeate concentration from each individualvessel.

Identifies which vessels in an array have highsalt passage. A System Profile should be taken at startup,

as a baseline record. Record complete system data whenever a

System Profile is performed.

PROBING


119/141

Probing is done while the system isoperating at normal conditions.

Insertion is normally done from the endopposite the permeate collectionmanifold.

PROBING

PROBING


120/141

Conc.

Feed

Permeate

CONDUCTIVITY

PROBING


121/141

CHANGE IN PRESSURE


122/141

CHANGE IN PRESSUREDROP

HIGHER

BIOFOULING SCALING INORGANIC FOULING HIGHER FLOWRATES LOWER FEED TEMPERATURES

LOWER

LOWER FLOWRATES

HIGHER FEED TEMPERATURES


123/141

CHANGE IN FEED PRESSURE

HIGHER SCALING PLUGGAGE FOULING HIGHER FEED TDS LOWER FEED

TEMPERATURE IMPROVER VALVING

LOWER HIGHER FEED

TEMPERATURE LOWER FEED TDS MEMBRANE

DAMAGE


124/141

CHANGE IN FEED CHEMISTRY

pH TOO HIGH = MEMBRANE DAMAGE

Ph TOO LOW = MEMBRANE DAMAGE

CHLORINE ABOVE = MEMBRANEVENDORS SPEC DAMAGE

SCALING IONS ABOVE SPEC = SCALING

INCREASED SDI OR TURNIDITY = FOULING

TROUBLESHOOTING OF RO


125/141

Too high system recovery : Concentration Polarization

Localized Salt Concentration

Causes :Operator errorFlow meter out of calibrationUnnoticed change in Feed water composition

SYSTEM

Troubleshooting of RO System


126/141

Common causes for high pH Buildup of bacteria

g y

RO element manufacturing problem Elements moved from their original

marked position .


127/141



128/141

Severe membrane deterioration ormultiple problems:


TIMELY CORRECTIVE ACTION

Instrumentation


129/141

pH

Conductivity Rota meter. Pressure gauges. ORP

Thermometer Level switches Flow switches Pressure switches Electrical control

Instruments used in an RO system


130/141

130

R. O. PLANT LOGSHEET FORMAT (TYPICAL)DATE-

O/P R. W. AREA SMBS D. P. ANTI.D. P.

HRS.NaOCl D. P. I/L FLOW I/L PR. O/L PR. O/L FRC ON/OFF ON/OFF O/L PR. O/L SDI O/L FRC ORP READING FEED PR. REJ. PR. PERMEATE FLOW REJ. FLOW PERMEATEON/OFF (LPM) (KG/CM2) (KG/CM2) (PPM) (KG/CM2) (PPM) (KG/CM2) (KG/CM2) (LPM) (LPM) (Microsieme

SIGN. OF OPERATOR SIGN. SUPERVISOR

G.F./D.M.F. C. F. R. O. BLOCK AREA


131/141

131

D. M PLANT LOGSHEET FORMAT (TYPICAL)DATE -

O/PHRS. ALUM D.P. NaOCL D.PI/L FLOW I/L PR. O/L PR. I/L PR. O/L PR. O/L FRC I/L PR. O/L PR. I/L PR. O/L PR. O/LCOND. O/L Ph

ON/OFF ON/OFF (M3/HR) (KG/CM 2) (KG/CM2) (KG/CM 2) (KG/CM 2) (PPM) (KG/CM2) (KG/CM 2) (KG/CM 2) (KG/CM 2)(m/cm2)

SIGN. OPERATOR SIGN. OF SUPERVISOR

SBAR.W. AREA DMF ACF SAC


132/141

132


133/141

133


134/141


135/141


136/141

AL KAL I BOI L OUT PROCEDURE


137/141


138/141

4. Determine the quantity of water added to the boiler and add a sufficient quantity ofMelrose Chemicals, Ltd A-420 or F-685 for the treatment in progress. Refer to theTechnical Bulletin of the product used to know its solubility. When the necessaryquantity of A-420 or F-685 is added, alkalinity "M" will be 3000 to 4000 ppm.5. A concentrated solution of the cleaner can be added proportionally to the feed waterwhile filling of the boiler. If there is an economiser in the system, the concentratedsolution must be added to there directly. In the case of small boilers or when the

conditions allow it, the concentrated solution can be added through a manhole or anyother opening located at the top of the boiler. Do not add solids to a boiler. The use of A-420 liquid for an alkaline boil-out eliminates any problem from deposits incurred bythe use of solid chemicals.6. Read and follow closely the instructions of the manufacturer of the boiler concerningthe firing stages and the evacuation of the vapours during an alkaline boil-out.7. In the case of new boilers, the drying of refractory materials can be combined withthe alkaline boil-out. Light a fire with wood to dry the boiler lining. Leave the chimneyopen until vapour appears - then close. If wood cannot be used, use oil. In installationswhere the oil is pulverized, it is often necessary to use a more easily controllable fuel.

The temperature of the furnace during the preliminarystages of boil-out must be low -


139/141

in order to obtain uniform drying - then can be graduallyincreased by varying the rate offuel addition or firing period to maintain the minimumpressure necessary during theboil-out. The suggested maximum pressure isapproximately 50% of the limit of

pressure for the valve operating with the lowestpressure. This pressure will createsufficient circulation in boilers having a waterwall and anetwork of complicated internal

piping.

8. It is difficult to precisely determine the optimal duration of analkaline boiling.Experience shows that 1 to 3 days are generally necessary for the


140/141

internal cleaning of aboiler. One prolonged period is better if drying of refractorymaterials is also carried out.The state and the appearance of the blowdown water of the boilerare the bestindication in knowing if the treatment should be continued or

stopped.9. For the duration of the boiling, all the safety measures must beobserved with regardto the superheaters, the economisers, etc. in order to avoid any

damage with theequipment. The superheaters and the economisers should beoperated in the sameway as when the system is operating. Detailed attention should begiven to the

at least every 8 hours. The total quantity of water removed from allthese points shouldbe roughly a quarter of the level indicated on the gauge, this


141/141

quantity being also dividedbetween the various drains and the continuous blowdown. Firstdrain the continuousblowdown, then progressing toward the drains on lower level ofthe boiler. Following thisoperation, the water level in the boiler should be restored by using

water containing thealkaline cleaner, so that the concentration of the cleaner in theboiler is not reduced bythese regular purges.

11 At the end of the boiling, cool the boiler gradually, then drainand flush the system byi d hi h Ch k h l li f h

training session on water treatment

Documents