Why are the only columns that receive gaseous and liquid phase ethylene for processing the deethanizer and the ethylene distillation column?
Thread Content
Why are the only columns that receive gaseous and liquid phase ethylene for processing the deethanizer and the ethylene distillation column?
Ethylene in gas-liquid phase is normally introduced during startup as a packing material, enabling reflux to be established in the entire tower in advance and thus reducing the time required for the product to meet quality standards. In cold separation, the material in the ethylene distillation column is closer to pure ethylene; therefore, the feed to the ethylene column needs to be started up. The deethanizer accepts gaseous and liquid ethylene during startup in order to establish full reflux throughout the column more quickly; since the material composition in this column is simple, it is difficult to supply heat, which hinders the rapid establishment of reflux. In addition to ethylene, it can also accept propylene, butadiene, etc., to establish reflux more smoothly. Just my personal opinion.