梯级利用烟气余热的超临界CO_(2)与ORC联合循环  

Cascade utilization of gas turbine waste heat with supercritical CO_(2) and ORC combined cycle

作　　者：高炜[1] 李红智[1] 张一帆[1] 杨玉[1] 韩煜航 GAO Wei;YANG Yu;LI Hongzhi;ZHANG Yifan;HAN Yuhang(Xi'an Thermal Power Research Institute,Co.Ltd,Xi'an,710054,China)

机构地区：[1]西安热工研究院有限公司,陕西西安710054

出　　处：《电力科技与环保》2023年第6期505-513,552,共10页Electric Power Technology and Environmental Protection

基　　金：陕西省创新能力支撑计划(2023-CX-TD-18)。

摘　　要：燃机+底层循环是目前可行性高、效率高、变负荷能力强的重要分布式能源技术,目前成熟的燃机底层循环是传统的蒸汽朗肯循环。为进一步提高燃机综合利用效率,寻找到可以更好的与燃机余热热源匹配并最大化余热发电量的新型底层循环,研究分析了包括有机朗肯循环(organic rankine cycles,ORC),超临界二氧化碳(supercritical carbon dixide,S-CO_(2))布雷顿循环,以及其组合形式。采用模拟计算的方法,理论分析了S-CO_(2)布雷顿循环与ORC联合循环余热利用的整体效果。对回热器和烟气加热器进行了?损失分析,对透平、压缩机、泵等设备进行了能量分析,揭示了各种循环性能优劣的本质。结果显示,几种新形式联合循环的余热发电量都比电厂原有蒸汽循环发电量大,本文提出的S-CO_(2)布雷顿循环与ORC联合循环可以比美国电力研究所(Electric Power Research Institute,EPRI)提出的复杂S-CO_(2)布雷顿循环相对多提供4.2%的余热发电量,并且本文的新型联合循环参数耦合效应弱,操作性更强。The combination of a gas turbine and bottoming cycle is the most feasible,efficient,and flexible distributed energy technology.The mature bottoming cycle for gas turbines is the traditional steam Rankine cycle.In order to further improve the overall efficiency of gas turbines and find a better matching bottoming cycle that maximizes the power output,various studies have analyzed including organic Rankine cycles(ORC),supercritical carbon dioxide(S-CO_(2))Brayton cycles,and their combination.This paper simulates and analyzes the overall performance of the utilization of waste heat using the S-CO_(2) Brayton cycle and ORC combined cycle.Exergy loss analyses were conducted on the recuperator and gas heater,and energy analyses were performed on equipment such as turbines,compressors,and pumps to reveal the intrinsic performance differences among various cycles.The results show that the waste heat power generation of the new combined cycles is higher than that of the original steam cycle in power plants.The new S-CO_(2) Brayton cycle and ORC combined cycle in this paper can provide 4.2% more power generation than the most complex S-CO_(2) Brayton cycle suggested by the Electric Power Research Institute(EPRI),and the coupling effects of the parameters in this new combined cycle are weak,leading to stronger operability.In conclusion,the simplest combination of S-CO_(2) Brayton cycle and wet working fluid organic cycle is proposed as the optimal form of combined cycle.

关 键 词：S-CO_(2)布雷顿循环 ORC 联合循环 余热回收 分布式能源 

分 类 号：TK02[动力工程及工程热物理] X773[环境科学与工程—环境工程]