双吸收升温型热泵驱动电厂碳捕集的方案研究  

Study on Post Combustion CO_2 Capture in Power Plant Integrated With Double Absorption Heat Transformer

作　　者：戴宇泽 王丹丹 刘锋[1,2] 李胜 高林[1,2] DAI Yu-Ze;WANG Dan-Dan;LIU Feng;LI Sheng;GAO Lin(Institute of Engineering Thermophysics,Chinese Academy of Sciences,Beijing 100190,China;University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国科学院工程热物理研究所,北京100190 [2]中国科学院大学,北京100049

出　　处：《工程热物理学报》2018年第11期2347-2355,共9页Journal of Engineering Thermophysics

基　　金：国家重点基础研究发展计划(973计划)(No.201CB249202)

摘　　要：本文提出了一种CO_2捕集的新方法,利用双吸收升温型热泵提升汽轮机末级蒸汽的品位,使之与CO_2再生温度相互匹配后用于富液的解析,同时回收锅炉排烟热量,预热进入热泵的循环水,进一步降低CO_2捕集能耗。本文利用Aspen Plus 11.0对流程进行模拟,并对关键过程的结果进行了实验验证。研究表明,随着CO_2捕集率逐渐增加,机组发电效率增幅呈现先增后减的趋势:对于350 MW的机组,当捕集率为53.65%时,新方案效率增幅达到最大,相对常规捕集方案效率能够提升2.06个百分点;当CO_2捕集率为90%时,新方案CO_2捕集能耗下降10.5%,效率提升幅度为1.25个百分点;此方法实现了热能品位的对口利用,降低了CO_2再生过程的不可逆损失,为电厂降低CO_2捕集能耗提供了一种新思路。In this paper, a new CO2 capture method is proposed. A double absorption heat transformer （DAHT） will be employed to upgrade the energy level of the low-temperature extraction steam from the last stage of the steam turbine and make the temperature of the steam more matched with the CO2 regeneration process. At the same time, the exhaust heat in the flue gas of the boiler will be recovered to preheat the circulation water and thereby the energy penalty can be further reduced. The system is simulated with the aid of Aspen Plus software and the results are verified by the experimental data. The results show that the power efficiency enhancement in the proposed method has a trend of increase first and then decrease with CO2 capture rate. For a 350 MW coal-fired power plant, the optimum CO2 capture rate is 53.65% and the corresponding efficiency enhancement is 2.06 percentage points. With 90% CO2 capture rate, 10.5% energy penalty can be reduced in the proposed method compared with the traditional mode, and the energy efficiency will be improved by 1.25 percentage points. In our study, the cascade utilization of the thermal energy is achieved and the irreversible destruction in the CO2 regeneration process is reduced. The investigation in this paper provides a new way to reduce the energy penalty in CO2 capture.

关 键 词：燃烧后CO2捕集 双吸收升温型热泵 烟气余热回收 品位提升 流程优化 

分 类 号：TK219[动力工程及工程热物理—动力机械及工程]