System for adjusting hydrogen-carbon ratio of synthesis gas and simultaneously producing byproduct hydrogen through coupling of membrane separation and pressure swing adsorption

The invention discloses a system for adjusting the hydrogen-carbon ratio of synthesis gas and simultaneously producing a byproduct hydrogen by coupling membrane separation and pressure swing adsorption, wherein raw material gas firstly enters a membrane separator, permeate gas and impermeable gas are obtained under the pushing of the pressure difference of two sides of a separation membrane, the permeate gas is subjected to pressure swing adsorption to purify high-concentration product hydrogen and desorption gas with higher carbon monoxide concentration, the desorption gas is pressurized by a compressor and then is mixed with the membrane separation impermeable gas to form the synthesis gas with the hydrogen-carbon ratio meeting the requirement. The amount of permeate gas entering pressure swing adsorption is adjusted by adjusting the operation pressure of membrane separation or the membrane separation area, so that the hydrogen production amount of pressure swing adsorption is adjusted, and the hydrogen-carbon ratio of the synthesis gas is adjusted. The advantages of two gas separation methods of membrane separation and pressure swing adsorption are fully utilized, the whole set of system is low in energy consumption, no exhaust waste gas is generated, and the purposes of adjusting the hydrogen-carbon ratio of the synthesis gas and producing high-concentration hydrogen as a byproduct are achieved at the same time.