化工进展 ›› 2019, Vol. 38 ›› Issue (04): 2046-2055.doi: 10.16085/j.issn.1000-6613.2018-0740

• 资源与环境化工 • 上一篇    下一篇

燃煤电厂烟气MDEA/PZ混合胺法碳捕集工艺模拟分析

林海周1,2(),罗海中1,裴爱国1,方梦祥2()   

  1. 1. 中国能源建设集团广东省电力设计研究院有限公司,广东 广州 510663
    2. 浙江大学能源清洁利用国家重点实验室,浙江 杭州 310027
  • 收稿日期:2018-04-11 修回日期:2018-05-30 出版日期:2019-04-05 发布日期:2019-04-05
  • 通讯作者: 方梦祥 E-mail:linhaizhou@gedi.com.cn;mxfang@zju.edu.cn
  • 作者简介:<named-content content-type="corresp-name">林海周</named-content>(1989—),男,博士后,研究方向为燃煤电厂烟气二氧化碳捕集。E-mail:<email>linhaizhou@gedi.com.cn</email>。|方梦祥,教授,博士生导师,研究方向为煤及生物质燃烧和气化技术、CO2控制技术。E-mail:<email>mxfang@zju.edu.cn</email>。
  • 基金资助:
    广东省自然科学基金博士启动项目(2018A030310692);基金项目:中国能源建设集团广东省电力设计研究院博士后科研项目(EV04531W)

Simulation and analysis of carbon dioxide capture process using MDEA/PZ blend solution in a coal-fired power plant

Haizhou LIN1,2(),Haizhong LUO1,Aiguo PEI1,Mengxiang FANG2()   

  1. 1. China Energy Engineering Group Guangdong Electric Power Design Institute Co., Ltd., Guangzhou 510663, Guangdong China
    2. State Key Laboratory of Clean Energy Utilization, Zhejiang University, Hangzhou 310027, Zhejiang, China
  • Received:2018-04-11 Revised:2018-05-30 Online:2019-04-05 Published:2019-04-05
  • Contact: Mengxiang FANG E-mail:linhaizhou@gedi.com.cn;mxfang@zju.edu.cn

摘要:

采用混合胺吸收剂替代传统一乙醇胺(MEA)吸收剂是降低有机胺法碳捕集工艺能耗的重要方法。利用Aspen plus软件模拟了以甲基二乙醇胺(MDEA)/哌嗪(PZ)混合胺为吸收剂的燃煤电厂每年百万吨CO2捕集工艺系统,考察了贫液负荷、MDEA/PZ混合胺浓度、MDEA/PZ比例和解吸压力等因素对解吸塔再沸器热负荷和冷凝器冷负荷的影响。通过对这些影响因素下吸收塔内液相温度分布和CO2负荷分布变化揭示了MDEA/PZ对CO2的吸收特性。此外,进一步分析了不同影响因素下解吸塔内气液相CO2浓度驱动力和气液相级间温度驱动力分布特性,发现了强浓度驱动力和低温度驱动力分布更有利于降低再生能耗。研究表明,由30%MDEA和20%PZ组成的混合胺液在贫液负荷为0.08和解吸压力为2.02×105Pa时,再沸器热负荷和塔顶冷凝负荷分别为2.76GJ/tCO2和0.60GJ/tCO2,相比传统MEA吸收剂降低了20.92%和40.0%。

关键词: 燃煤电厂, 二氧化碳捕集, 混合胺, 过程模拟, 能耗, 驱动力

Abstract:

Amine blend is recognized as a promising alternative to traditional MEA solution for reducing the energy cost of post-combustion chemical absorption CO2 capture process. In this study, a coal-fired power plant CO2 capture system using the blend of methyldiethanolamine (MDEA) and piperazine (PZ) as an absorbent was simulated by Aspen plus soft at a capacity of 1 million tons CO2 one year. The effects of MDEA/PZ blend concentration, MDEA/PZ ratio, CO2 load in lean solution and stripping pressure on the stripper reboiler heat duty and condenser cool duty were investigated. The liquid phase temperature and CO2 load of the solution in the absorber under different conditions were analyzed to reveal the absorbing properties of MDEA/PZ blend. The CO2 concentration driving force and temperature driving force for the stripping process were also studied. The results showed that strong concentration driving force and weak temperature driving force favored the decrease of energy cost. The heat duty and cold duty for CO2 regeneration in stripper can be as low as 2.76GJ/tCO2 and 0.60GJ/tCO2, respectively under optimized conditions (30% MDEA and 20% PZ, 0.08 lean load, 2.02×105Pa stripping pressure), which were reduced by 20.92% and 40.0% compared to using traditional MEA solution.

Key words: coal-fired power plant, carbon dioxide capture, amine blends, process simulation, energy cost, driving force

中图分类号: 

  • X701.7