耦合溴化锂吸收式制冷与有机朗肯循环的合成气深冷分离工艺  

Syngas cryogenic separation process combined with lithium bromide absorption refrigeration and organic Rankine cycle

作　　者：李丹 杨思宇[1] 钱宇[1] LI Dan;YANG Siyu;QIAN Yu(College of Chemistry and Chemical Engineering,South China University of Technology,Guangzhou 510640,Guangdong,China)

机构地区：[1]华南理工大学化学与化工学院,广东广州510640

出　　处：《化工进展》2022年第10期5236-5246,共11页Chemical Industry and Engineering Progress

基　　金：国家自然科学基金重点项目(21736004)。

摘　　要：从合成气中深冷分离液化天然气(LNG)可以在调峰中发挥重要作用,并显著提升企业的经济效益。然而深冷分离的高能耗是实际工业中的一大问题。本文提出了耦合溴化锂吸收式制冷与有机朗肯循环的甲烷深冷分离工艺。新工艺可以利用原压缩制冷系统的余热从而降低制冷能耗。又因为压缩级数与能耗和可利用余热量成正相关,为使得系统的能耗最低,需同时优化压缩级数与所耦合的余热利用系统。采用自适应遗传算法对新工艺中8种不同压缩级数组合进行优化,通过对比各模型的总能耗、性能系数和单位能耗确定了能耗最低的流程。其结果表明,相比于原工艺总能耗减少了34%;性能系数增加了0.07;单位能耗减少了0.89kW/kg。经济表现为操作费用减少了33%;新增设备投资2550万元,理论上一年即可回收投资成本。The LNG separated from syngas by cryogenic liquefaction unit plays an important role in peak regulation, and significantly improves the economic benefits. However, the high energy consumption of cryogenic separation is a big problem in existing industries. In this paper, a cryogenic separation process coupled with lithium bromide absorption refrigeration and organic Rankine cycle was proposed. The waste heat is recovered from original compression refrigeration system, reducing the total refrigeration energy consumption. The compression stage was positively related to energy consumption and available waste heat. In order to minimize the energy consumption of the system, it was necessary to optimize the compression stages and the waste heat utilization system at the same time. The novel process of eight combination of compression stages was optimized by adaptive genetic algorithm. Then the lowest energy consumption was determined by comparing the total energy consumption, performance coefficient and unit energy consumption of each model. The results showed that the total energy consumption was reduced by 34% compared with the original process. The coefficient of performance was increased by 0.07, while the unit energy consumption was reduced by 0.89kW/kg. The economic performance showed that the novel process decreased operating cost by 33% and increased capital cost by 25.5 million. The capital cost can be recovered within one year, indicating the feasibility of novel process in economic.

关 键 词：溴化锂吸收式制冷 有机朗肯循环 遗传算法 计算机模拟 集成 

分 类 号：TQ03-39[化学工程]