Membrane-based CO2 Removal System

The membrane-based biogas CO₂ removal system consists of two sections: pretreatment and purification & separation. In the pretreatment section, the biogas from the desulfurization unit is first fed into a compressor for pressurization, and then sent to the drying unit for water removal. The resulting dry, oil-free compressed biogas flows into the membrane separation and purification unit.

The core component of the purification & separation section is the membrane module. By precisely controlling temperature and pressure, effective separation of CO₂ and methane is achieved. Product gas (natural gas product) is obtained on the high-pressure side of the membrane, with CO₂ concentration below 3%, methane recovery rate ≥90% for single-stage membrane separation and ≥99% for two-stage membrane separation. CO₂ off-gas is withdrawn from the low-pressure side of the membrane.