name of the subject is chemical engineering sophmore seminar (che200 )

Description of the process:

Ethylene

The feed (ethanol) enters the process at a temperature and pressure of 25C and 1 atm and at a composition of 95 wt% ethanol and 5 wt% water.

It is initially pressurized to 4335 kPa using a centrifugal pump and subsequently heated to 400C using a specific equipment.

The heated and pressurized feed enters the fixed bed reactor and contacts with the aluminum oxide catalyst. At this point it dehydrates to form the product, ethylene, as well as the byproducts water, hydrogen, diethyl ether and acetaldehyde.

The pressure of the reactor effluent is increased to 4500 kPa by compressor and the temperature decreased to 100C by exchange with cold water in heat exchanger.

The stream then expands and flashes in flash vessel, which separates out 82.3% of the unreacted ethanol, 96.6% of the water and virtually all of the acetaldehyde contaminant in the bottoms while sending the ethylene-rich vapor phase out of the top.

The top product is compressed to 3500 kPA and cooled to 0.0 C by a freon refrigerant in.

At this point the stream is flashed for a second time in a vessel to remove additional impurities.

The top outlet stream consists of 99.5 wt% ethylene, which is fed to the bottom of a 10tray absorption column that removes a fraction of the residual diethyl ether as well as the remainder of the unreacted ethanol.

A stream of absorbent water is fed to the top of the column. The product exits the top of the column and has a purity of 99.7% ethylene. Diethyl ether makes up 0.2% of the remaining product stream and is the primary contaminant.

Questions:

1-Draw a process flow diagram (PFD) of the process. (Choose the appropriate units, label all units and streams)

- The feed (ethanol) enters the process at a temperature and pressure of 25C and 1atm and at a composition of 95wt% ethanol and 5wt% water. - It is initially pressurized to 4335kPa using a centrifugal pump and subsequently heated to 400C using a specific equipment. - The heated and pressurized feed enters the fixed bed reactor and contacts with the aluminum oxide catalyst. At this point it dehydrates to form the product, ethylene, as well as the byproducts water, hydrogen, diethyl ether and acetaldehyde. - The pressure of the reactor effluent is increased to 4500kPa by compressor and the temperature decreased to 100C by exchange with cold water in heat exchanger. - The stream then expands and flashes in flash vessel, which separates out 82.3% of the unreacted ethanol, 96.6% of the water and virtually all of the acetaldehyde contaminant in the bottoms while sending the ethylene-rich vapor phase out of the top. - The top product is compressed to 3500kPA and cooled to 0.0C by a freon refrigerant in. - At this point the stream is flashed for a second time in a vessel to remove additional impurities. - The top outlet streamer consists of 99.5wt% ethylene, which is fed to the bottom of a 10 tray absorption column that removes a fraction of the residual diethyl ether as well as the remainder of the unreacted ethanol. - A stream of absorbent water is fed to the top of the column. The product exits the top of the column and has a purity of 99.7% ethylene. Diethyl ether makes up 0.2% of the remaining product stream and is the primary contaminant. Questions: 1. Draw a process flow diagram (PFD) of the process. (Choose the appropriate units, label