analysis assignment two tasks: prepare a partial mass balance run lab experiments and calculate...

Analysis Assignment

Two Tasks: Prepare a partial mass balance Run lab experiments and calculate kinetic coefficients

Analysis Assignment Don Robinson

Required Files Information about the assignment

is in “Analysis & Planning” Background information is in

“Basic Data” See “Laboratory Facilities” for

instructions on how to run the lab reactor simulator program

Analysis Assignment Don Robinson

Mass Balance Streams Feed to Syngas process Output from Syngas process Added CO2 Feed to methanol process Intermediate step: 100% CO=>CO2 Output from methanol process

(100% conversion, not equilibrium)

Analysis Assignment Don Robinson

Components Methane Water Hydrogen CO CO2 Nitrogen Methanol

Analysis Assignment Don Robinson

Components cont. Also include total stream Units: kg-moles/hr

Analysis Assignment Don Robinson

Catalyst Analysis Objective Arrhenius constants (A & E) methanol + CO2 + 3H2 => ethanol + 2H2O ethanol + 5CO2 + 15H2 => fusel oil +

10H2O 2ethanol => acetone + methanol + H2 E in kJ/kg-mol A’s (same as kf,kr) some combination of

kg-mol, hours, m3

Analysis Assignment Don Robinson

Simulated Runs Reactor size (1X2 or 2X12.5 cm) Temperature (200 & 225°C) Pressure (fixed at 3900 kPa) Feed rate (.5 to 20 kg/hr) Methanol & Ethanol rates (50-2000

gms/hr)

Analysis Assignment Don Robinson

Data InputRun Specifications

Reactor Size 0

Temperature 200 CFeed Rate 1 kg/hrMethanol Rate 0 gms/hrEthanol Rate 0 gms/hr

Small

Analysis Assignment Don Robinson

Summary of ConditionsResults

Run Number 1 2Reactor Diameter cm 1 1Reactor Length cm 2 2Temperature C 200 200Feed Rate kg/hr 1 1Methanol Rate gms/hr 0 100Ethanol Rate gms/hr 0 0

Analysis Assignment Don Robinson

FeedMass Fraction Base Feed FeedMethane 0.18 0.18 0.163636Water 0.05 0.05 0.045455Hydrogen 0.11 0.11 0.1CO 0.02 0.02 0.018182CO2 0.48 0.48 0.436364Nitrogen 0.16 0.16 0.145455Methanol 0 0 0.090909Acetone 0 0 0Heptanol 0 0 0Ethanol 0 0 9.09E-12

Analysis Assignment Don Robinson

ProductProduct Product

Methane 0.179998 0.163636Water 0.05052 0.045752Hydrogen 0.109831 0.099906CO 0.020046 0.018221CO2 0.478724 0.435639Nitrogen 0.159998 0.145455Methanol 0.000883 0.091389Acetone 2.15E-13 9.8E-13Heptanol 9.55E-11 3.19E-10Ethanol 3.24E-07 1.75E-06

Analysis Assignment Don Robinson

Forward Rate Const. Calcs Consider the simple case of A + B C Rate = kf [A] [B] Rate in moles per hour per m3

[A],[B] in moles/m3

Base rate on void volume (void fraction = .33)

What is the missing parameter?

Analysis Assignment Don Robinson

Molar Density Required to convert mole fraction to

moles/m3 Get from HYSYS model “Start.hsc”

on CD in “Files” Suggestion: Get one density (at

average feed conditions) for each temperature you are going to run at and apply this to the whole reactor

Analysis Assignment Don Robinson

Variation of K,kf,kr With T Arrhenius equation k = A*exp(-E/RT) Since we will know the k’s at two

different T’s, the only issue is what value of R to use

Perry’s Handbook has a table of R values in various units

HYSYS wants E in kJ/kg-mol

Analysis Assignment Don Robinson

Entering Data in HYSYS

Analysis Assignment Don Robinson

Check Base, Phase, Units

Analysis Assignment Don Robinson

Schedule A group: Today, Friday, next week

Wednesday B group: Wednesday, next week

Monday, Friday If necessary a session on Saturday

27th

Due at start of class Monday September 29