Biogas is recommended to be a potential fuel source that can provide a continuous supply of compressed natural gas in forms of Bio-compressed natural gas. Different technologies proposed to enrich methane in biogas mixture such as cryogenic process, membrane process, physical and chemical absorption, water scrubber, pressure swing adsorption (PSA). PSA is guaranteed as gas purification technology in air separation, gas drying application, and hydrogen enrichment. Recently, PSA applications extended to include other areas such as the methane enrichment into biogas mixture. PSA is an efficient purification process owing to the low energy penalty, low installation and operation cost, and simple and safe operation. The optimization of the PSA process can follow two paths mainly adsorbent modification, and/or developments in the PSA process design. This work outlines the fundamentals of the pressure swing adsorption unit by investigating the main innovative process engineering approaches that improved the performance of the PSA process. Previous research about the PSA, simulation and experimental examination for biogas upgrading are also introduced and significant findings highlighted. Besides, the paper discusses the impact of some parameters on the performance of the PSA process such as bed porosity, pressure and time of adsorption, sizing of PSA unit, and purge to feed ratio. Also, the evaluation parameters of the PSA process have been presented. PSA technology is a versatile process and alternative to other enrichment technologies, we expect that it will remarkably contribute to the Biogas industry in the future.

建议将沼气作为潜在的燃料来源，以生物压缩天然气的形式连续提供压缩天然气。提出了多种技术来丰富沼气中的甲烷，例如低温工艺，膜工艺，物理和化学吸收，水洗涤塔，变压吸附（PSA）。PSA作为空气净化，气体干燥应用和氢气浓缩中的气体净化技术得到保证。最近，PSA的应用范围扩展到其他领域，例如将甲烷富集到沼气混合物中。PSA由于具有低能耗，低安装和运行成本以及简单安全的操作而成为一种高效的净化过程。PSA工艺的优化可以遵循两条路径，主要是吸附剂的改性和/或PSA工艺设计的发展。这项工作通过研究提高PSA工艺性能的主要创新工艺技术方法，概述了变压吸附装置的基本原理。还介绍了有关PSA，沼气升级模拟和实验检查的先前研究，并着重指出了重要发现。此外，本文还讨论了一些参数对PSA工艺性能的影响，例如床孔隙率，吸附压力和吸附时间，PSA单元的尺寸以及吹扫进料比。此外，还介绍了PSA过程的评估参数。PSA技术是一种通用工艺，可替代其他浓缩技术，我们希望它将在未来为沼气行业做出巨大贡献。