化工进展 ›› 2024, Vol. 43 ›› Issue (10): 5890-5900.DOI: 10.16085/j.issn.1000-6613.2023-1603

• 资源与环境化工 • 上一篇    

新型的BHEP-醚水溶液相变吸收二氧化硫

刁忠秀1(), 郑宇1, 魏凤玉1(), 宋小良2, 苏文国2, 李淑全2   

  1. 1.合肥工业大学化学与化工学院,安徽 合肥 230009
    2.双盾环境科技有限公司,江苏 无锡 214205
  • 收稿日期:2023-09-11 修回日期:2024-01-20 出版日期:2024-10-15 发布日期:2024-10-29
  • 通讯作者: 魏凤玉
  • 作者简介:刁忠秀(1999—),女,硕士研究生,研究方向为化工传质与分离技术。E-mail:diaozhongxiu@gmail.com

Phase-change absorption for SO2 capture by a novel aqueous BHEP/ether solution

DIAO Zhongxiu1(), ZHENG Yu1, WEI Fengyu1(), SONG Xiaoliang2, SU Wenguo2, LI Shuquan2   

  1. 1.School of Chemistry and Chemical Engineering, Hefei University of Technology, Hefei 230009, Anhui, China
    2.Shuangdun Environment Technology Company, Wuxi 214205, Jiangsu, China
  • Received:2023-09-11 Revised:2024-01-20 Online:2024-10-15 Published:2024-10-29
  • Contact: WEI Fengyu

摘要:

针对有机胺湿法烟气脱硫过程能耗高的问题,本文开发了一种新型的N,N′-双(2-羟乙基)哌嗪有机胺(BHEP)/二乙二醇二乙醚(DEGDEE)水系液-液相变吸收剂,并研究其吸收解吸SO2性能及相变机理。结果表明,BHEP与二氧化硫(SO2)反应生成了极性较强的铵盐,与非极性醚差异较大,产生盐析效应而导致其分相。上相中DEGDEE的浓度很高,质量分数大于97%,胺、SO2和水的质量分数低于1%,可直接循环使用;约有99%以上的胺和SO2富集在下相,只需对下相解吸,从而大大地降低了能耗。有机胺BHEP和DEGDEE的浓度越高,越易发生相变,下相体积占比和DEGDEE分配率越小,SO2和BHEP的分配率几乎不受影响;两者浓度太高时还会发生吸收前分相。DEGDEE对SO2的物理吸收使体系的吸收能力提高,在质量分数15% BHEP水溶液中加入质量分数20%的DEGDEE后,循环吸收容量和解吸率分别提高了6.43%和10.59%,能耗降低了13.69%,该相变吸收剂具有较好的应用前景。

关键词: 液-液相变, 哌嗪类有机胺, 醚, SO2捕集, 吸收, 解吸

Abstract:

Due to the high energy consumption in SO2 capture by organic amine solution, a novel liquid-liquid phase-change absorbent composed of N,N'-bis(2-hydroxyethyl) piperazine (BHEP) organic amine, diethylene glycol diethyl ether (DEGDEE) and water was developed. The absorption-desorption performance and phase-change mechanism were also investigated. There was a significant polarity difference between nonpolar ether and the polar ammonium salts formed by the reaction of BHEP and SO2. Consequently, the phase-change occurred when the ammonium salts separated from the nonpolar ether. The content of DEGDEE in the upper phase was higher than 97%, while the contents of BHEP, SO2, and H2O were lower than 1%. Therefore, the upper phase could be directly recycled. Over 99% of BHEP and SO2 were concentrated in the lower phase. Accordingly, only the SO2-rich phase went to the stripper for the thermal regeneration, and thus the energy consumption could be effectively reduced. The higher the content of BHEP or DEGDEE, the easier the phase separation, and the smaller the proportion of the lower phase volume and the DEGDEE distribution rate. In addition, the content of both distribution rates of SO2 and BHEP had almost unaffected. However, when the concentrations of both SO2 and BHEP were too high, DEGDEE was immiscible with BHEP before SO2 scrubbing. The physical absorption of SO2 by DEGDEE resulted in an enhancement of the absorption capacity for SO2 by BHEP. Moreover, the cyclic absorption capacity and desorption rate with the mixture of 15% BHEP+20% DEGDEE+65% H2O were increased by 6.43% and 10.59%, respectively, and the energy consumption was decreased by 13.69%, as compared to a 15% BHEP solution. All the results showed that the biphasic solvent proposed had a promising prospects for sulfur dioxide capture.

Key words: liquid-liquid phase-change, piperazine-based organic amine, ether, SO2 capture, absorption, desorption

中图分类号: 

京ICP备12046843号-2;京公网安备 11010102001994号
版权所有 © 《化工进展》编辑部
地址:北京市东城区青年湖南街13号 邮编:100011
电子信箱:hgjz@cip.com.cn
本系统由北京玛格泰克科技发展有限公司设计开发 技术支持:support@magtech.com.cn