HYDROCARBON GAS PROCESSING

摘要

The processing of gas streams containing hydrocarbons and other gases of similar volatility to recover high yields of components such as ethane, propane, and heavier hydrocarbons therefrom by cooling said gas stream under pressure to form a liquid portion, and expanding the liquid portion to a pressure lower than feed pressure whereby a part of the liquid portion vaporizes to cool the remaining part of the liquid portion is improved by pre-cooling the liquid portion prior to flash expansion. In one embodiment this is accomplished by dividing the remaining part of the liquid portion into a first and second stream, directing the first liquid stream into heat exchange relation with the liquid portion of the feed stream prior to expansion to warm the first liquid stream and pre-cool the liquid portion prior to expansion. Both first and second liquid streams are then supplied to a fractionating column, the second stream being supplied to the fractionating column at a point thereon higher than the first stream. Several other methods of pre-cooling the liquid portion are also described.