Simple simulation of propane liquification

Simple Simulation of Propane Liquefaction

This process starts with propane vapor at ambient conditions (298 K and 1 bar which is compressed to 15 bar, cooled back down to 298 K, expanded through an adiabatic valve to 1 bar then the resulting gaseous and liquid streams are separated. Since propane is not an ideal gas throughout the process because of the conditions (high pressure and the presence of both a gas and a liquid), the Peng Robinson equation of state will be used as the thermodynamic model, though other equations of state could have been chosen.

Methodology

Step1:Start new simulation

Step2: Select engineering units for the simulation

Step3: Create a flow sheet

Choose the equipment then connect them

Then connect them

Step4: Select chemical components for the process

Step5: Select K‐value and enthalpy options for the process

Step6: Define the feed streams used in the process

Step7: Enter specifications for the unit operations

1- Compressor Specifying

2- Heat exchanger

3- Valve

4- Flash Separator

Step8: Run the simulation

Review Results

Compressor

Output Streams

While the process just simulated would work for the liquefaction of propane, it would not be acceptable since the propane vapor leaving the separator is released to the atmosphere, which is an economic problem, since it is a valuable resource, and an environmental problem, being explosive and a greenhouse gas. A simple way to deal with this is to recycle the propane vapor back into the process by mixing it with the feed and returning it to the compressor.

Make a recycle to the process

1-Insert a mixer unit

2 -Reroute Propane vapor stream (Stream 5)

3 -Select cut stream

5- Run simulation

Generate a Report