低能耗碳捕集技术及燃煤机组热经济性研究  

Research on low energy consumption CO capture technology and thermal economy of coal-fired units

作　　者：赵红涛 王树民 张曼 ZHAO Hong-tao;WANG Shu-min;ZHANG Man(China Energy lnvestment Corporation,Beijing 100011,China;China Shenhua Coal to Liquid and Chemical Co.,Ltd.,Beijing 100011,China;School of Chemical and Environmental Engineering,North China Institute of Science and Technology,Langfang 065201,China)

机构地区：[1]国家能源投资集团有限责任公司,北京100011 [2]中国神华煤制油化工有限公司,北京100011 [3]华北科技学院化学与环境工程学院,河北廊坊065201

出　　处：《现代化工》2021年第1期210-214,共5页Modern Chemical Industry

基　　金：国家重点研发计划项目(2017YFB0603300);廊坊市科学技术研究与发展计划项目(2020011011)。

摘　　要：针对燃烧后胺法脱碳工艺捕集能耗高的问题,在普通碳捕集系统中集成级间冷却、机械蒸气再压缩(mechanical vapor recompression,MVR)和富液分流解析3项节能技术,建立低能耗碳捕集系统,并将该系统与600 MW燃煤机组热力系统耦合,分析该系统对燃煤机组热经济性指标的影响。结果表明,当CO_(2)捕集率为90%时,该碳捕集系统中单位再生能耗从4.09 GJ/t CO_(2)降低到2.64 GJ/t CO_(2),降幅达35.28%。与耦合普通碳捕集系统的燃煤机组相比,耦合低能耗碳捕集系统燃煤机组的电厂效率从30.81%增加到33.53%,提升了2.72%;标准煤耗从398.87 g/kWh降低到366.81 g/kWh,下降了32.06 g/kWh;热耗率从11674.92 kJ/kWh降低到10736.53 k J/k Wh,减少了938.36 k J/k Wh,热经济性得到明显改善。研究还发现,CO_(2)捕集率每降低1%,低能耗碳捕集燃煤机组的电厂效率增加0.054%,标准煤耗降低0.524 g/kWh,热耗率降低15.353 k J/kWh,降低碳捕集率可进一步改善电厂的热经济性。Aiming to solve the problem that the regeneration of post-combustion amine decarburization process consumes high energy,a low energy consumption CO_(2) capture system is established through integrating three energysaving technologies in the common CO_(2) capture system,including inter-stage cooling,mechanical vapor recompression and rich liquid split desorption.This system is then coupled with the thermodynamic system of a 600 MW coal-fired unit,and the impact on the thermal economic indicators of the coal-fired unit is analyzed.Results show that as CO_(2) capture ratio is 90%,the energy consumption per unit of CO_(2) regeneration in this system drops from 4.09 GJ/t CO_(2) to 2.64 GJ/t CO_(2),a decrease of 35.28%.Compared with a coal-fired unit coupled with the common carbon capture system,the power plant efficiency of a coal-fired unit coupled with this low energy consumption carbon capture system increases from30.81%to 33.53%,an increase of 2.72 percentage;the standard coal consumption decreases from 398.87 g/k Wh to366.81 g/k Wh,a decrease of 32.06 g/k Wh;the heat consumption rate decreases from 11,674.92 k J/k Wh to 10736.53 k J/k Wh,a decrease of 938.36 k J/k Wh,and the thermal economy has significantly been improved.It is found that as CO_(2) capture ratio decreases by every 1%,the power plant efficiency of the low energy consumption carbon capture coal-fired units will increase by 0.054%,the standard coal consumption will decrease by 0.524 g/k Wh,and the heat consumption rate will decline by 15.353 k J/k Wh.Reducing CO_(2) capture ratio can further improve the thermal economy of power plants.

关 键 词：燃煤烟气 CO_(2) 再生能耗 节能 热经济性 

分 类 号：TQ110.9[化学工程—无机化工]