HYDROCARBON GAS PROCESSING

摘要

Recovery of ethane, ethylene, propane, propylene, and heavier hydrocarbon components from a hydrocarbon gas stream. The stream is cooled and divided into first and second streams. The first stream is further cooled to condense it and is thereafter expanded to the fractionation tower pressure and supplied to the tower at mid-column. The second stream is expanded to the tower pressure and is supplied to the tower at mid-column. A distillation stream is withdrawn from the column below the feed point of the second stream and compressed, and is heat-exchanged with the tower overhead vapor stream to cool the distillation stream and condense it, forming a condensed stream which is the tower top feed. The system is effective to maintain the overhead temperature of the tower at an effective recovery temperature. The distillation stream can be withdrawn from the column above the feed point of the second stream.