Dehumidification performance of wet flue gas in coal-fired power plant

doi:10.11949/j.issn.0438-1157.20170224

Abstract

Abstract:

The flue gas after FGD emitted in coal-fired power plant contains a large amount of water vapor,which means a great waste of water resources. The liquid desiccant-based dehumidification is a feasible technology to recover water from flue gas. To study the dehumidification performance of this technology, a laboratory scale adiabatic tube falling film dehumidifier was built with CaCl₂ solution as desiccant. The performance of this technology and the effect of solution temperature, concentration, mass transfer area and air inlet temperature was investigated. The mass transfer coefficient was given by 0.009-0.040 m·s^-1. Moreover, a comparison between condensation and liquid desiccant-based dehumidification was carried out. The data showed that the water recovery efficiency would be more than 50%, which was much better than condensation method and confirmed the feasibility of this technology applied in power plants.

Key words: flue gas, absorption, water recovery, solution, tube falling film

摘要：

燃煤电厂湿法脱硫后排放的烟气中含有大量水蒸气，造成大量水资源的浪费，溶液除湿工艺是水分回收技术之一。通过绝热型管式降膜除湿试验台，采用价格低廉的CaCl₂溶液为除湿剂，探究了湿烟气状态下溶液浓度、溶液温度、传质面积及进口温度对除湿性能的影响，试验得到了CaCl₂溶液除湿过程的传质系数，溶液除湿效率远高于清水冷凝除湿，为烟气除湿工艺的选择和性能预测提供了参考。

关键词: 烟道气, 吸收, 除湿, 水溶液, 管式降膜

CLC Number:

X701

LÜ Yang, DONG Yong, TIAN Luning, HAN Zhenan, SHEN Kai, CUI Lin, ZHANG Liqiang, LI Yuzhong. Dehumidification performance of wet flue gas in coal-fired power plant[J]. CIESC Journal, 2017, 68(9): 3558-3564.

吕扬, 董勇, 田路泞, 韩哲楠, 申凯, 崔琳, 张立强, 李玉忠. 燃煤电厂湿烟气的除湿特性[J]. 化工学报, 2017, 68(9): 3558-3564.

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