Abstract: A heat integrated distillation column provides heat at each theoretical stage of distillation in a heating portion and coolant at each theoretical stage of distillation in a cooling portion.

Abstract: An improved ethane recovery system and process which increases the recovery of ethane up to about 99% with no increase in plant residue compression horsepower. The improved ethane recovery process employs an additional fractionation column which receives two vapor streams in different regions thereof which allows the fractionation column to produce the top reflux to the demethanizer column.

Abstract: Increased recovery of propane, butane and other heavier components found in a natural gas stream is achieved by installing an absorber upstream from an expander and a separator. The separator is downstream from the expander and returns the liquid stream generated by the separator back to the absorber. Additionally, the recovery of propane, butane and other heavier components is enhanced by combining the upper gas stream from a distillation column with the upper gas stream from the absorber prior to injecting this combination into the separator. The upper gas stream removed from the separator is then subsequently processed for the recovery of a predominately methane and ethane gas stream while the bottom liquid stream from the absorber is subsequently distilled for the generation of a stream consisting predominately of propane, butane and other heavy hydrocarbon components. Alternate embodiments include an additional reflux separator in the system, or substitution of an additional absorber for the separator.