Tail gas processing for liquid hydrocarbons synthesis

A method of using a tail gas stream of a pressure swing absorption (PSA) apparatus, comprising:

• compressing and reforming said tail gas stream for producing CO and H2;
• mixing said tail gas stream with a mixture of natural gas and steam for producing a tail gas mixture;
• heating the tail gas mixture to at least 500° C. but not more than 650° C.;
• feeding the heated tail gas mixture to a reformer reactor for producing a synthesis gas stream;
• cooling said synthesis gas stream;
• directing a portion of the cooled synthesis gas stream to a membrane separator for producing a hydrogen depleted stream;
• and
• mixing the hydrogen depleted stream with a remaining portion of the synthesis gas stream for achieving a select ratio of H2 to CO in said synthesis gas stream.

An apparatus for using a tail gas stream of a pressure swing absorption (PSA) apparatus, comprising:

• means for compressing and reforming (170) the PSA tail gas stream (14) for producing CO and H2;
• means for mixing (41) a tail gas stream (40) with a mixture of natural gas and steam (34), the mixing means in fluid communication with the compressing and reforming means (170);
• a first heat exchanger (140) in fluid communication with the mixing means (41) for heating the mixture to at least 500° C. but not more than 650° C.;
• a reformer reactor (190) in fluid communication with the first heat exchanger (140) to produce a synthesis gas stream (48);
• a second heat exchanger (A) disposed to receive and cool the synthesis gas stream (48);
• means for separating (51) the cooled synthesis gas stream into a first portion (52) directed to a membrane separator (180) to produce a hydrogen depleted stream (54), and a second portion (56);
• and
• means for mixing (57) said hydrogen depleted stream (54) with the second portion (56) to achieve a select ratio of H2:CO in said second portion (56) of the synthesis gas stream to provide a mixed stream (58) with a reduced H2:CO ratio.