Simulate Equilibrium Reactor

PROBLEM STATEMENT

 The new application of hydrogen as a raw  for fuel cells for mobile power source (PEM fuel cells) requires that the inlet gas have a concentration lower than 10-20 ppm.

 Otherwise, the anode is poisoned and the cell efficiency abruptly drops. Hence, if the hydrogen is produced from hydrocarbon or alcohol reforming, purification is required in 

 order to reduce the CO levels to cell requirements. The most technologically feasible purification train consist of a water gas shift reaction (WGS). 

The reaction 

CO + H20 <----------------->CO2 + H2 

has been employed for 40 years in the industrial process for H2 production from liquid and gaseous hydrocarbon. The role of the WGS reaction is to increase the H2 yield and decrease the CO concentration, which is a poison for some catalyst used.

LEARNING OUTCOMES

>Simulate equilibrium reactor and reactions in HYSYS. 

>Re-Add the reactions and reaction 

>Attach reaction sets to the fluid package. 

SEE VIDIO PART1 AND 2

part2

part1

 

Conversion of HYSYS Simulation

PROBLEM STATEMENT . 

Develop a model that represents partial oxidation of methane to produce hydrogen. 

• Given the following

 conditions; Fluid package: Peng- Robinson Temperature: 25°C. Molar flow for CH4 : 100 kgmole/hr

 Pressure: 2 bar. Molar flow for Air(79% N2 & 21% O2): 260 kgmole/hr %Conversion: 40% and 60% for

 Rxn 1 and 2 resp

BUILDING THE SIMULATION

 • Access Hysys. 

Define Simulation Basis. 

• Add reactions. Add reaction sets. Make sequential reactions. 

• Attach reaction to fluid package. Add feed streams 

• Add the conversion reactor 

 

Flash Separator

 

INTRODUCTION • 

A flash separator is a device or an equipment used in several industrial applications to separate a vapour- liquid mixture. It is performed to determine the product condition and phases. It is referred also to as flash drum or knock- out drums.

PROBLEM STATEMENT 

We have a stream containing 15% ethane, 20% propane, 60% i- butane, and 5% n- butane at 50°F and atmospheric pressure and a flowrate of 100lbmoles/hr. Th compressed to 50 psia, and then cooled to 32°F. The resulting vapour and liquid are to be separated as the two product streams. What the flowrates and compositions of these two streams?

Hysys Simulation of Pump

 Estimate the outlet temperature of n-hexane and note down 

the duty of the pump 

Use hysys to find solution   

ex: estimate n-hexane pressure in 3 atm to 10 atm 

 

Adding Material Streams

 

 Hysys simulation -

>Starting HYSYS 

>Simulation Basis Manager

>Creating A New Simulation

>Adding Components to the Simulation

>Selecting A Fluids Package 

>Selecting Thermodynamics Model 

>Enter Simulation Environment

>Adding Material Streams

>Review and Summary Problems

Hydrogen Recovery from Refinery Off-gases

Background 

Hydrogen is one of the main intermediate products largely utilized in oil and petrochemical industries.

 

• It is used as a raw material and obtained in some processes as a by-product.

 

• The off-gas streams contain considerable amount of hydrogen, which are

 

mostly incinerated in refinery flares as a waste gas.

 

>Hydrocarbons are converted into hydrogen reformers in order to produce

 

the hydrogen needed for hydrogen consuming processes.

 

>Separation of hydrogen from an existing refinery off-gas stream

 

represents an opportunity to achieve significant cost reductions in refineries

>Cryogenic Technology (CT)

 

Separation principle:

 

Cryogenic technology is based on the difference in the relative

 

component volatility at low temperatures.

 

Disadvantages:

 

Extra compressors to increase the pressure at least 20 bar. CO2 separation is necessary to avoid freezing the CO2 in line at low temperatures.

see simulation 

 

Design of Heat Exchanger using ASPEN Shell & Tube Exchanger

 example:

Design an exchanger to sub-cool condensate from a methanol condenser from 95°C to

40°C. Flow-rate of methanol 100,000 kg/h. Cooling water will be used as the coolant,

with a temperature rise from 25°C to 40°C.

1.

Determine the heat exchanger duty

In this example, since coolant is more corrosive, it is assigned to the tube side.

Specific heat capacity of methanol = 3.926kJ/kg°C

Heat Exchanger Duty

Q = mCp.(AT) =(100000/3600) × 3926 × (95 – 40) =

 5998.056 × 10³W = 5998.056kW

2.

Specific heat capacity of water[= 4.2kJ/kg°C

Mass flowrate of cooling water:

mwater= Q/Cp.water (Twater out-Twater.in)= (5998056/4200(40-25))= kg/S 95.21 = 342360 kg/hr

Using 1-2 Shell and Tube Heat Exchanger,

Log Mean Temperature Difference:

see simulation