韩冰,王子阳,田相峰,张克舫,巩亮,刘浩璇
HAN Bing,WANG Ziyang,TIAN Xiangfeng,ZHANG Kefang,GONG Liang,LIU Haoxuan

• 1:国家能源集团龙源(北京)碳资产管理技术有限公司
• 2:中国石油大学(华东)新能源学院

摘要(Abstract)：

化学吸收法碳捕集技术是燃煤电厂脱碳的重要途径，但高能耗制约了其发展。集成MVR热泵的工艺流程改进作为降低捕集能耗的重要手段，现有研究大多以软件模拟优化该流程，存在约束条件选取不灵活、参数优化仅对MVR环节局部优化和模拟流程繁琐等缺点。为弥补以上研究不足，以300 MW机组及年产量200万t碳捕集系统数据为基础，对集成MVR热泵的解吸单元进行约束条件设置灵活、优化过程直观的整体建模优化。首先建立MEA吸收CO_2热力学模型及MVR热泵设备数学模型，得到MVR热泵工艺流程设计参数。在此基础上，以最小等量解吸能耗为目标函数，对贫富液换热器小端差及二次蒸汽压缩终压进行优选。之后基于优选结果，在二次蒸汽压缩终压为140 kPa,贫富液换热器小端差为5℃时，对MVR系统闪蒸压力进行优化。优化结果表明，最优闪蒸压力为109.2 kPa,捕集系统最小等量解吸能耗为2.82 GJ/t(以CO_2计),相比于常规碳捕集系统节能率(5.61%)节能效果明显。对集成MVR热泵的节能优化方案的经济性分析结果表明，节能方案总投资为708.28万元，年净收益523.55万元，收益净现值为3 449.2万元，投资动态回收期为1.5 a。
Chemical absorption method is an important way to capture carbon dioxide in coal-fired power plants, but the high energy consumption in the process restricts its development.The carbon capture process integrated MVR pump is an important means to reduce energy consumption. The main drawbacks of current researches, which mainly use software for simulation optimization, are inflexible selection of constraint conditions, the local optimization of parameters for the MVR part and complicated simulation process. In order to address the lack of researches, based on the data of the carbon capture system that captures 2 million tons of carbon dioxide annually, the overall modeling optimization of the desorption unit integrated with MVR pump was carried out with flexible constraint selection and simple and intuitive optimization process. Firstly, the thermodynamic model of CO_2 absorption by MEA and the mathematical model of MVR heat pump equipment were established, and the design parameters of the MVR heat pump process flow were obtained. On this basis, taking the minimum desorption energy consumption as the objective function, the small terminal difference and the final pressure of secondary steam compression of the lean and rich liquid heat exchanger were optimized. Then, based on the optimization results, the flash pressure of MVR system was optimized when the final pressure of secondary steam compression was 140 kPa and the small end difference of lean and rich liquid heat exchanger was 5 ℃. The optimization results show that the optimal flash pressure is 109.2 kPa, and the minimum equivalent desorption energy consumption of the capture system is 2.82 GJ/t(in terms of CO_2). Compared with the conventional carbon capture system, the energy saving is 5.61%,with obvious energy saving effect. The economic analysis results show that the investment of energy saving optimization scheme of integrating MVR pump is 7.082 8 million yuan, the annual net income is 5.235 5 million yuan, the net present value is 34.492 million yuan, and the dynamic payback period of the investment is 1.5 years.

关键词(KeyWords)： MEA吸收法;碳捕集系统;MVR;节能
MEA absorption method;carbon capture system;MVR;energy saving

Abstract:

Keywords:

基金项目(Foundation): 龙源电力股份有限公司2021年科技资助项目(LY2021-5)

作者(Author): 韩冰,王子阳,田相峰,张克舫,巩亮,刘浩璇
HAN Bing,WANG Ziyang,TIAN Xiangfeng,ZHANG Kefang,GONG Liang,LIU Haoxuan

DOI: 10.13226/j.issn.1006-6772.RM23031201

参考文献(References)：

• [1] 习近平.在第七十五届联合国大会一般性辩论上的讲话[J].中华人民共和国国务院公报，2020(28):5-7.XI Jinping.Statement at the general debate of the 75th session of the United Nations general assembly[J].Bulletin of the State Council of the People′s Republic of China,2020(28):5-7.
• [2] 毕夏，史长东，程竹，等.低碳背景下我国新能源行业利用现状及发展前景分析[J].东北电力大学学报，2012,32(5):86-90.BI Xia,SHI Changdong,CHENG Zhu,et al.The utilizing and developing analysis of China′s new energy industry under low-carbon background[J].Journal of Northeast Electric Power University,2012,32(5):86-90.
• [3] FAN J L,XU M,LI F,et al.Carbon capture and storage (CCS) retrofit potential of coal-fired power plants in China:The technology lock-in and cost optimization perspective[J].Applied Energy,2018,229:326-334.
• [4] 赵晓飞，杨晓宇，刘雅文.二氧化碳综合利用，路在何方?[J].中国石油和化工，2022(4):14-18.ZHAO Xiaofei,YANG Xiaoyu,LIU Yawen.Where is the way to comprehensive utilization of carbon dioxide?[J].China Petroleum and Chemical Industry,2022(4):14-18.
• [5] 吴彬，黄坤荣，刘子健.化学吸收法捕集二氧化碳研究进展[J].广州化工，2017,45(11):11-14.WU Bin,HUANG Kunrong,LIU Zijian.Research progress on carbon dioxide capture by chemical absorption[J].Guangzhou Chemical,2017,45(11):11-14.
• [6] 陆诗建，贡玉萍，刘玲，等.有机胺CO2吸收技术研究现状与发展方向[J].洁净煤技术，2022,28(9):44-54.LU Shijian,GONG Yuping,LIU Ling,et,al.Research status and future development direction of CO2 absorption technology for organic amine[J].Clean Coal Technology,2022,28(9):44-54.
• [7] 窦锦玲，何志强.化学法吸收烟气中CO2的实验研究[J] .化工管理，2017(21):77-78.DOU Jinling,HE Zhiqiang.Experimental study on chemical absorption of CO2 in flue gas [J].Chemical Management,2017(21):77-78.
• [8] XUE B Y,YU Y M,CHEN J,et al.A comparative study of MEA and DEA for post-combustion CO2 capture with different process configurations[J].International Journal of Coal Science and Technology,2017,4(1):15-24.
• [9] 赵红涛，王树民，张曼.低能耗碳捕集技术及燃煤机组热经济性研究[J].现代化工，2021,41(1):210-214.ZHAO Hongtao,WANG Shumin,ZHANG Man.Research on low energy consumption CO2 capture technology and thermal economy of coal-fired units[J].Modern Chemical Industry,2021,41(1):210-214.
• [10] LU S J,ZHAO D Y,ZHU Q M.CO2 absorber coupled with double pump CO2 capture technology for coal-fired flue gas [J].Energy Procedia,2018,154:163-170.
• [11] 陆诗建，高丽娟，王家凤，等.烟气CO2捕集热能梯级利用节能工艺耦合优化[J].化工进展，2020,39(2):728-737.LU Shijian,GAO Lijuan,WANG Jiafeng,et,al.Coupling optimization of energy-saving technology for cascade utilization of flue gas CO2 capture system[J].Chemical Progress,2020,39 (2):728-737.
• [12] 陆诗建，蒋超，康寿兴.基于MVR热泵的胺法捕集回收烟气中CO2[J].山东化工，2018,47(10):196-200.LU Shijian,JIANG Chao,KANG Shouxing.Recovery of CO2 in flue gas by amine method based on MVR heat pump[J].Shandong Chemical Industry,2018,47(10):196-200.
• [13] LI T C,YANG C N,TANTIKHAJORNGOSOL P,et al.Comparative desorption energy consumption of post-combustion CO2 capture integrated with mechanical vapor recompression technology[J].Separation and Purification Technology,2022,294:121202.
• [14] 李小飞，王淑娟，陈昌和.胺法脱碳系统流程改进及优化模拟[J].化工学报，2013,64(10):3750-3759.LI Xiaofei,WANG Shujuan,CHEN Changhe.Modification of process and optimization for CO2 capture systems using amine solution[J].Journal of Chemical Engineering,2013,64(10):3750-3759.
• [15] 张金鑫.胺法烟气CO2捕集工艺及热泵节能技术研究[D].青岛：中国石油大学(华东),2018.
• [16] XUE B Y,YU Y M,CHEN J,et al.A comparative study of MEA and DEA for post-combustion CO2 capture with different process configurations[J].International Journal of Coal Science and Technology,2017,4(1):15-24.
• [17] 李晗，陈建.单乙醇胺吸收CO2的热力学模型和过程模拟[J].化工学报，2014,65(1):47-54.LI Han,CHEN Jian.Thermodynamic modeling and process simulation for CO2 absorption into aqueous monoethanolamine solution[J].Journal of Chemical Engineering,2014,65(1):47-54.
• [18] ERIK T H,TORE H W,HALLYARD F S.Thermodynamic mod-els for CO2-H2O-alkanolamine systems,a discussion[J].Energy Procedia,2009,1:971-978.
• [19] CHEN C C,EVANS L B.A local composition model for the excess gibbs energy of aqueous electrolyte systems[J].AIChE Journal,1986,32(3):444-454.
• [20] LIU Y D,ZHANG L.Z,WATANASIRI S.Representing vapor-liquid equilibrium for an aqueous MEA-CO2 system using the electrolyte nonrandom-two-liquid model[J].Industrial & Engineering Chemistry Researc,1999,38:2080-2090.
• [21] AOUICHA B,ANTONIO R,ILHAM M,et al.Isothermal vapor-liquid equilibria of (monoethanolamine + water) and (4-methylmpholine + water) binary system at several temperatures[J].Journal of Chemistry and Engineering Data,2009,54:2312-2316.
• [22] 刘家祺.分离过程[M].北京：化学工业出版社，2002.
• [23] 韩莎莎，孙晓岩，陈玉石，等.电解质NRTL模型研究与开发[J] .计算机与应用化学，2019,36(3):185-194.HAN Shasha,SUN Xiaoyan,CHEN Yushi,et,al.Research and development of electrolyte NRTL model[J].Computer and Applied Chemistry,2019,36 (3):185-194.
• [24] 郭天民.多元气-液平衡和精馏[M].北京：石油工业出版社，2002.
• [25] 黄文峰.基于低成本塑料填料和高效板式换热器的CO2化学吸收技术及工艺研究[D].杭州：浙江大学，2022.
• [26] VIVIANI C Onishi,MOHAMMAD H Khoshgoftar Manesh,RAQUELSalcedo-Díaz,et al.Thermo-economic and environmental optimization of a solar-driven zero-liquid discharge system for shale gas wastewater desalination[J].Desalination,2021,511:115098.
• [27] XU C,LI X S,XU G,et al.Energy,exergy and economic analyses of a novel solar-lignite hybrid power generation process using lignite pre-drying[J].Energy Conversion and Management,2018,170:19-33.
• [28] 郭中旭.基于供热机组负荷特性的吸收式热泵变工况分析[D].北京：华北电力大学，2017.