Department of Applied Chemistry and Chemical Technology, University of Karachi, Pakistan.
Department of Chemical Engineering, NED University of Engineering and Technology, Karachi, Pakistan.
Chemosphere. 2022 Nov;307(Pt 4):136001. doi: 10.1016/j.chemosphere.2022.136001. Epub 2022 Aug 17.
Purification of Natural gas is vital for utilizing it as a source of energy harvesting for the world. Amine-based chemical absorption technique is the most utilized in the gas field for the purification of gas that ensures the purity of the sweet gas stream with the elimination of carbon dioxide. However, it is considered an energy-intensive process to deal with considerable energy loss and environmental damage to the ecosystem. Five cases have been developed in this study based on various blends comprising mono and tertiary amines in combination with piperazine with a focus on the use of Aqueous Monodiethanolamine (Aq. MDEA), Aqueous Monoethanolamine (Aq. MEA) and piperazine (Pz) for the CO sequestration from the sour natural gas extracted from the remote location located in the province of Baluchistan in Pakistan. The use of exergy, advanced exergy, and exergo environment for optimizing and selecting a suitable solvent combination that may result in an effective separation process has been proposed. Five cases have been developed based on various blends such as mono and tertiary amines combined with piperazine. From the results of all the studied scenarios, Case IV, based on the combination of Aqueous monoethanolamine and piperazine, provides reduced exergy destruction of 2551.7 KW. It was observed that the maximum removal of CO around 99.87 wt% is achieved in case IV. In addition, advance exergy analysis also highlights that case-IV has a venue of 25% exergy destruction avoidable, which would further enhance its performance. Nevertheless, still, case-IV has 75% exergy destruction unavoidable. The environmental factors show that Case-IV has a reduced exergy destruction factor of 0.96, a highly environmentally benign choice as a solvent with a high value of 1.03, and case-IV has the higher operational stability and higher exergy efficiency with an exergy stability value of 0.40. Therefore, monoethanolamine combined with piperazine to be an effective and efficient solvent blend that could be an energy-effective approach for sweetening the natural gas.
天然气的净化对于将其作为世界能源采集的来源至关重要。基于胺的化学吸收技术是天然气领域中最常用的净化技术，可确保甜气流的纯度，并消除二氧化碳。然而，该技术被认为是一种能源密集型过程，会导致大量能源损失和对生态系统的环境破坏。本研究基于各种混合物开发了五个案例，这些混合物由单胺和叔胺与哌嗪组合而成，重点使用水合单乙醇胺（Aq. MDEA）、水合单乙醇胺（Aq. MEA）和哌嗪（Pz）从巴基斯坦俾路支省偏远地区提取的酸性天然气中捕获 CO。本研究提出了使用火用、先进火用和火用环境来优化和选择合适的溶剂组合，以实现有效分离过程。本研究基于各种混合物，如单胺和叔胺与哌嗪的组合，开发了五个案例。从所有研究方案的结果来看，基于水合单乙醇胺和哌嗪组合的案例四提供了 2551.7 KW 的减少火用破坏。观察到在案例四中实现了 CO 的最大去除率，约为 99.87 wt%。此外，先进火用分析还强调，案例四有 25%的火用破坏是可以避免的，这将进一步提高其性能。尽管如此，案例四仍有 75%的火用破坏是不可避免的。环境因素表明，案例四具有较低的火用破坏因子 0.96，是一种环境友好的溶剂选择，其值为 1.03，案例四具有较高的操作稳定性和较高的火用效率，其火用稳定性值为 0.40。因此，单乙醇胺与哌嗪结合是一种有效且高效的溶剂混合物，可以作为一种节能的天然气脱硫方法。
