Hybrid membrane-vacuum pressure swing adsorption: low-cost technology for simultaneous biomethane and carbon dioxide production from biogas

Biogas production and upgrading allow to reduce methane and carbon dioxide emission through simultaneous production of biomethane and CO₂. Membrane and vacuum pressure swing adsorption technologies can achieve this goal in a single unit, but currently these technologies have a high upgrading costs. Here, we developed a hybrid configuration, which benefits from the advantages of both technologies while having a lower upgrading cost and cost uncertainty. The hybrid configuration delivers a biomethane stream with methane purity > 96 % and methane recovery > 99 % as well as a CO₂ stream with CO₂ purity > 95 % and CO₂ recovery > 93 %. The new hybrid process showed ∼ 15 % reduction in upgrading cost in the most probable cases. The hybrid configuration is robust and less complex compared to benchmark technology. The hybrid configuration achieves high efficiency and could enable a new generation of upgrading technology for simultaneous biomethane production and CO₂ capture.