Methane enrichment for biogas purification using pressure swing adsorption techniques

Abstract

Biogas is a highly potential renewable fuel source substituting fossil-based natural gas. To commercialize biomethane, biogas purification systems via selective removal of CO2 are a crucial step for the production of biomethane. Technologies based on pressure swing adsorption (PSA) are widely used and achieve promising results, such as water scrubbing, membrane separation, cryogenic processes, chemical absorption, and physical absorption. This review describes the potential of PSA as a technology to separate CO2 from biogas to purify biomethane. PSA is an efficient technology for biogas purification having a low energy penalty, low cost and a safe operation. Nowadays, different biomethane purification technologies are operated, such as cryogenic separation, membrane operations and absorptive separation. The PSA process, as one of the main technology, and its concepts are described. Then, the main process engineering approaches for efficient biogas purification are analyzed. Different adsorbents are compared and key process performance variables are evaluated. Next, the results of different studies on adsorption materials and the yield of real examples as well as the current research trends and improvement potentials are presented and discussed.