Impact of feed changes in the ethylene distillation column of an ethylene plant
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At present, due to an abnormality in the separation system of the ethylene plant, the concentration of carbon tertiary compounds in the ethylene distillation tower – which is designed to separate ethylene from ethane – has risen to 15–20% by volume. This results in insufficient purity of the ethane product at the bottom of the tower; while the designed purity is 99%, the actual purity is only around 70%. Some of these impurities are carbon tertiary compounds, while the rest is ethylene, leading to a high loss of ethylene at the bottom of the tower, at a level of 15% by volume. I would like to ask how it is possible to reduce this loss of ethylene without shutting down the plant.
Excessive carbon terpene content refers to an excessive level of carbon terpenes in the feedstock
There is a problem with the previous deethanizer; trimers are being carried over to the ethylene tower, and it is necessary to prevent an excessive amount of trimers from reaching the subsequent systems. The C3s are located at the bottom of the ethylene column; heavy components there cause the heat exchange efficiency of the reboiler at the column bottom to decline, resulting in a poorer separation effect. r
In the case of a pre-depropanization process, it is recommended to check the operating condition of the high-pressure tower and whether the C3 separation ratio is normal. Also, investigate the type of feed used in cracking to see if the amount of C3 in the system increases significantly afterward