MEMBRANE PERMEATE RECYCLING PROCESS FOR APPLICATION IN ADSORPTION PROCESSES AT VARIABLE PRESSURE Russian patent published in 2023 - IPC B01D53/47 B01D53/22 C01B3/50 

FIELD: gas industry.

SUBSTANCE: membrane permeate recycling processes using hydrogen recovery units and pressure swing adsorption units. Method for processing a dry gas stream is proposed, including: directing the dry gas stream to a compressor to produce a pressurized gas stream; directing the pressurized gas flow to the pressure swing adsorption unit to obtain a ready hydrogen stream and a residual gas stream; directing a portion of the tail gas stream to a first membrane unit to produce a first permeate stream and a first non-permeate stream; recycling the first permeate stream and mixing with the dry gas stream; directing a portion of the tail gas stream to a second membrane unit to produce a second permeate stream and a second non-permeate stream; passing the second permeate stream without additional compression to the pressure swing adsorption unit; and passing the first non-permeate stream and the second non-permeate stream into the absorber unit; wherein the first membrane unit and the second membrane unit are hydrogen selective, and wherein the second permeate stream from the second membrane unit is recycled to the pressure swing adsorption unit as purge gas. In another embodiment, a similar process for treating the dry gas stream is provided, which further includes controlling the flow of the tail gas stream to the first membrane unit and the second membrane unit.

EFFECT: group of inventions provides for creation of an improved membrane separation process, which provides a reduction in operating and capital costs, as well as an efficient extraction of hydrogen.

9 cl, 5 dwg