Spinning globe

All the Details Behind Purification


The purpose of the purification unit is to produce an ethylene gas stream that has a purity of 99.9wt% of ethylene. The distillation column that is going to be used to achieve this purity is usually a large one. There are as many as 125 stages in a typical column. The column is operated at a pressure of 700 to 2800kPa. Its overhead condenser and bottom reboiler are operated at a temperature of -40 to -90 degrees celcius, and -15 to -65 degrees celcius, respectively. At such a high purity, the distillation column requires a high reflux ratio. Sometimes acetylene is found in the gas stream. Instead of removing the acetylene, hydrogen is added to hydrogenate it and form ethylene.


Start Over

Go Back

Continue