基于过程拆分的半闭式超临界CO_(2)循环热力学分析及流程优化  

Thermodynamic Analysis and Process Optimization of a Semi-closed Supercritical CO_(2)Cycle Using Process Splitting Method

作　　者：于良 辛团团 张逸飞[1] 许诚[1] YU Liang;XIN Tuantuan;ZHANG Yifei;XU Cheng(Key Laboratory of Power Station Energy Transfer Conversion and System,Ministry of Education,North China Electric Power University,Beijing 102206,China)

机构地区：[1]华北电力大学电站能量传递转化与系统教育部重点实验室,北京102206

出　　处：《动力工程学报》2024年第6期991-1000,共10页Journal of Chinese Society of Power Engineering

基　　金：国家自然科学基金青年科学基金资助项目(52306008);国家自然科学基金资助项目(52176004);中央高校科研基金资助项目(2023MS016)。

摘　　要：面对日益紧迫的减碳降耗需求,发展高效低碳的先进热力循环愈发重要。提出了一种基于天然气的零碳排放的半闭式超临界CO_(2)循环,并通过工质拆分,将半闭式循环拆解为开式循环和闭式循环,以阐明循环热功转化的过程;进一步采用循环拆分法将复杂重构循环拆解为若干简单循环,建立不同流程重构措施的热力学评价模型,直观地揭示不同循环构型的节能机理;通过参数敏感性分析获得各个流程改良措施关键参数的最优点。结果表明:再热、分流再压缩、中间冷却、部分冷却等多种循环流程改良措施均可有效提高循环效率,其效率增益为1.79~5.59个百分点;多种流程改良措施集成优化后,系统净发电效率较基础循环提高10.18个百分点。In the face of the increasingly urgent need for the reduction of carbon emission and energy consumption,the development of efficient advanced thermal cycles with low carbon emission is becoming more and more important.A natural gas fueled semi-closed supercritical CO_(2)cycle was proposed with zero carbon emission,and the semi-closed cycle was split into an open cycle and a closed cycle through working fluid splitting to further clarify the thermal to power conversion process.Furthermore,the cycle splitting method was applied to the complex modified cycle,which was split into several simple cycles to formulate the thermodynamic evaluation models of the different process modification measures and intuitively reveal the energy-saving mechanism of different cycle configurations.Through parameter sensitivity analysis,the optimum parameters of process modification measures were obtained.Results show that the cycle efficiency can be effectively improved by various cycle layout modification measures such as reheating,recompression,intermediate cooling and partial cooling,which can contribute to the efficiency improvement of 1.79~5.59 percentage points.After the integration and optimization of various process modification measures,the net power generation efficiency of the system is increased by 10.18 percentage points compared with the basic cycle.

关 键 词：超临界CO_(2)循环 碳捕集 循环拆分法 半闭式循环 

分 类 号：TK229.2[动力工程及工程热物理—动力机械及工程]