不同工质在溶液除湿真空再生系统中的性能对比

doi:10.11949/0438-1157.20230646

摘要/Abstract

摘要：

对一种溶液除湿真空再生系统进行了实验及模拟研究，实验对比了LiCl溶液及CaBr₂∶CaCl₂=1∶1(溶质的质量分数比)混合溶液的系统性能，发现两溶液的出口含湿量及COP较为接近，当驱动温度为62℃时，系统COP均为0.65左右。通过模拟研究发现，两种溶液的除湿能力十分接近，混合溶液的COP略高于LiCl溶液。驱动温度84℃时，采用混合溶液的出口含湿量为6.0 g/kg左右，系统COP为0.81左右。进口含湿量越高，系统COP将会越高，得益于混合溶液较小的比热容，其再生溶液的耗热量略低，因此其COP略高于LiCl溶液。在此类溶液除湿系统中，CaBr₂∶CaCl₂=1∶1混合溶液能较好地替代LiCl溶液，实现低成本，高性能。

关键词: 溶液除湿, 混合溶液, 对比研究, 数值模拟, 性能分析

Abstract:

An experimental and simulation study on a liquid desiccant dehumidification system with vacuum regeneration is carried out in this paper. The experiment compares the system performance of LiCl solution and mixed solution of CaBr₂∶CaCl₂=1∶1. It is found that the outlet moisture content and COP of the two solutions are relatively close. When the driving temperature is 62℃, the system COP is about 0.65. The simulation results show that the dehumidification performances of the two solutions are very close under the same heat and mass transfer coefficient, and the COP of the mixed solution is slightly higher than that of the LiCl solution. At the driving temperature of 84℃, the outlet humidity of the mixed solution is about 6.0 g/kg, and the system COP is about 0.81. The higher the inlet humidity, the higher the system COP will be. Due to the lower specific heat capacity of the mixed solution, the heat consumption of the mixed solution in the regenerator is slightly lower, resulting in a slightly higher COP than that of the LiCl solution. In summary, the mixed solution of CaBr₂-CaCl₂=1∶1 can be a good substitute for LiCl solution in the liquid desiccant dehumidification system, which can achieve low cost and high performance.

Key words: liquid desiccant dehumidification, mixed solution, comparative study, numerical simulation, performance analysis

中图分类号:

TK 115

程小松, 殷勇高, 车春文. 不同工质在溶液除湿真空再生系统中的性能对比[J]. 化工学报, 2023, 74(8): 3494-3501.

Xiaosong CHENG, Yonggao YIN, Chunwen CHE. Performance comparison of different working pairs on a liquid desiccant dehumidification system with vacuum regeneration[J]. CIESC Journal, 2023, 74(8): 3494-3501.

图/表 10

参考文献 20

21	Yon H R, Cai W J, Wang Y Y, et al. Dynamic model for a novel liquid desiccant regeneration system operating in vacuum condition[J]. Energy and Buildings, 2018, 167: 69-78.
22	Yon H R, Cai W J, Wang Y Y, et al. Performance investigation on a novel liquid desiccant regeneration system operating in vacuum condition[J]. Applied Energy, 2018, 211: 249-258..
23	高文忠, 时亚茹, 韩笑生, 等. 混合除湿盐溶液液滴闪蒸机理[J]. 化工学报, 2012, 63(11): 3453-3459.
	Gao W Z, Shi Y R, Han X S, et al. Droplet flash evaporation of mixed dehumidification solutions[J]. CIESC Journal, 2012, 63(11): 3453-3459.
24	韩雨松, 邹同华, 邓赛峰. 不同真空度下除湿溶液再生性能的试验研究[J]. 流体机械, 2016, 44(3): 70-75.
	Han Y S, Zou T H, Deng S F. Experimental study on performance of desiccant-solution regeneration in different vacuum degree[J]. Fluid Machinery, 2016, 44(3): 70-75.
25	解鸣, 茆春俊, 吕雯, 等. 基于热管传热的除湿溶液真空再生过程实验研究[J]. 制冷学报, 2019, 40(6): 103-110.
	Xie M, Mao C J, Lv W, et al. Experimental study of the vacuum regeneration process of a dehumidifying solution based on heat pipe heat transfer[J]. Journal of Refrigeration, 2019, 40(6): 103-110.
26	彭冬根, 程小松, 李霜玲, 等. 一种新型溶液除湿装置数学模型及性能分析[J]. 太阳能学报, 2019, 40(2): 474-479.
	Peng D G, Cheng X S, Li S L, et al. Mathematical model and performance analysis of a new liquid desiccant dehumidifier[J]. Acta Energiae Solaris Sinica, 2019, 40(2): 474-479.
27	Liu X H, Jiang Y, Qu K Y. Heat and mass transfer model of cross flow liquid desiccant air dehumidifier/regenerator[J]. Energy Conversion and Management, 2007, 48(2): 546-554.
28	Zhang F, Yin Y G, Cao B W, et al. Performance analysis of a novel dual-evaporation-temperature combined-effect absorption chiller for temperature and humidity independent control air-conditioning[J]. Energy Conversion and Management, 2022, 273: 116417.
29	Che C W, Yin Y G. A statistical thermodynamic model for prediction of vapor pressure of mixed liquid desiccants near saturated solubility[J]. Energy, 2019, 175: 798-809.
1	Yin Y G, Zhang X S, Chen Z Q. Experimental study on dehumidifier and regenerator of liquid desiccant cooling air conditioning system[J]. Building and Environment, 2007, 42(7): 2505-2511.
2	成洁, 殷勇高, 张凡. 低品位热驱动混合溶液除湿降温系统性能分析[J]. 东南大学学报(自然科学版), 2019, 49(1): 148-153.
	Cheng J, Yin Y G, Zhang F. Performance analysis of liquid desiccant cooling system using mixed solution driven by low-grade heat source[J]. Journal of Southeast University (Natural Science Edition), 2019, 49(1): 148-153.
3	Liu J, Liu X H, Zhang T. Performance comparison and exergy analysis of different flow types in internally-cooled liquid desiccant dehumidifiers (ICDs)[J]. Applied Thermal Engineering, 2018, 142: 278-291.
4	Longo G A, Gasparella A. Experimental and theoretical analysis of heat and mass transfer in a packed column dehumidifier/regenerator with liquid desiccant[J]. International Journal of Heat and Mass Transfer, 2005, 48(25/26): 5240-5254.
5	Guan B W, Zhang T, Liu J, et al. Review of internally cooled liquid desiccant air dehumidification: materials, components, systems, and performances[J]. Building and Environment, 2022, 211: 108747.
6	Varela R J, Yamaguchi S, Giannetti N, et al. General correlations for the heat and mass transfer coefficients in an air-solution contactor of a liquid desiccant system and an experimental case application[J]. International Journal of Heat and Mass Transfer, 2018, 120: 851-860.
7	Liu X H, Zhang Y, Qu K Y, et al. Experimental study on mass transfer performances of cross flow dehumidifier using liquid desiccant[J]. Energy Conversion and Management, 2006, 47(15/16): 2682-2692.
8	关博文, 张勤灵, 张涛, 等. 溶液除湿式空气处理机组在锂电池生产厂房中的应用[J]. 暖通空调, 2022, 52(3): 100-104, 161.
	Guan B W, Zhang Q L, Zhang T, et al. Application of liquid desiccant air handling units to lithium battery production workshops[J]. Heating Ventilating & Air Conditioning, 2022, 52(3): 100-104, 161.
9	彭冬根, 徐少华. 蒸发冷却条件下管内LiCl和CaCl₂溶液降膜除湿性能对比[J]. 化工学报, 2020, 71(4): 1554-1561.
	Peng D G, Xu S H. Experimental comparison on dehumidification performance of LiCl and CaCl₂ under evaporative cooling condition[J]. CIESC Journal, 2020, 71(4): 1554-1561.
30	Patil K R, Chaudhari S K, Katti S S. Thermodynamic properties of aqueous solutions of lithium iodide: simplified method for predicting the enthalpies from the vapor-pressure data[J]. Applied Energy, 1991, 39(3): 189-199.
10	沈子婧, 殷勇高, 张小松. 基于氯化钙溶液的混合盐溶液除湿剂物性测量[J]. 化工学报, 2016, 67(7): 3004-3009.
	Shen Z J, Yin Y G, Zhang X S. Measurement and analysis of physical properties of mixed liquid desiccants based on calcium chloride solution[J]. CIESC Journal, 2016, 67(7): 3004-3009.
11	王沐, 殷勇高, 郭枭爽, 等. 经济型多元溶液的替代方案及除湿再生性能验证[J]. 化工学报, 2018, 69(S2): 420-424.
	Wang M, Yin Y G, Guo X S, et al. Alternative scheme and dehumidification and regeneration performance validation for economic multi-component solution[J]. CIESC Journal, 2018, 69(S2): 420-424.
12	Wen T, Luo Y M, Wang M, et al. Comparative study on the liquid desiccant dehumidification performance of lithium chloride and potassium formate[J]. Renewable Energy, 2021, 167: 841-852.
13	Longo G A, Gasparella A. Three years experimental comparative analysis of a desiccant based air conditioning system for a flower greenhouse: assessment of different desiccants[J]. Applied Thermal Engineering, 2015, 78: 584-590.
14	Varela R J, Giannetti N, Saito K, et al. Experimental performance of a three-fluid desiccant contactor using a novel ionic liquid[J]. Applied Thermal Engineering, 2022, 210: 118343.
15	Cao B W, Yin Y G, Zhang F, et al. Experimental study on heat and mass transfer characteristics between a novel ionic liquid and air under low-humidity conditions[J]. International Journal of Heat and Mass Transfer, 2022, 198: 123373.
16	Liu X H, Yi X Q, Jiang Y. Mass transfer performance comparison of two commonly used liquid desiccants: LiBr and LiCl aqueous solutions[J]. Energy Conversion and Management, 2011, 52(1): 180-190.
17	Lazzarin R M, Gasparella A, Longo G A. Chemical dehumidification by liquid desiccants: theory and experiment[J]. International Journal of Refrigeration, 1999, 22(4): 334-347.
18	Li X W, Zhang X S, Cao R Q, et al. Progress in selecting desiccant and dehumidifier for liquid desiccant cooling system[J]. Energy and Buildings, 2012, 49: 410-418.
19	童守宝, 车春文, 殷勇高. CaBr₂溶液除湿再生性能及腐蚀性实验研究[J]. 东南大学学报(自然科学版), 2022, 52(3): 425-432.
	Tong S B, Che C W, Yin Y G. Experimental study on dehumidification and regeneration performance and corrosiveness of CaBr₂ solution[J]. Journal of Southeast University (Natural Science Edition), 2022, 52(3): 425-432.
20	Chen X J, Riffat S, Bai H Y, et al. Recent progress in liquid desiccant dehumidification and air-conditioning: a review[J]. Energy and Built Environment, 2020, 1(1): 106-130.

名称	类型	准确度	范围
温度计	T型热电偶	±0.1℃	-10~120℃
温湿度传感器	Vaisala HMT120	温度: ±0.1℃；湿度: ±1.5%	温度范围: -40~60℃；湿度范围:0~100%
空气流量计	KIMO CP300	±1 m³/h	0~9999 m³/h
电磁流量计	KQ-LDBF-15S-T2F1-000D	±0.5%	0.16~2.5 m³/h
电磁流量计	KQ-LDBF-15S-M2F1-001D	±0.5%	0.318~6 m³/h

名称	类型	准确度	范围
温度计	T型热电偶	±0.1℃	-10~120℃
温湿度传感器	Vaisala HMT120	温度: ±0.1℃；湿度: ±1.5%	温度范围: -40~60℃；湿度范围:0~100%
空气流量计	KIMO CP300	±1 m³/h	0~9999 m³/h
电磁流量计	KQ-LDBF-15S-T2F1-000D	±0.5%	0.16~2.5 m³/h
电磁流量计	KQ-LDBF-15S-M2F1-001D	±0.5%	0.318~6 m³/h

参数	数值
热水流量/（m³/h）	3.9
冷却水流量/（m³/h）	4.5
冷凝器冷却水进口温度/℃	27.5
除湿溶液流量/（m³/h）	3.6
再生溶液流量/（kg/s）	2
空气流量（混合溶液）/（m³/h）	2000
空气流量（LiCl溶液）/（m³/h）	2400
空气进口温度/℃	27~28
除湿溶液进口温度/℃	26~27
除湿再生循环流量/（kg/s）	0.3

参数	数值
热水流量/（m³/h）	3.9
冷却水流量/（m³/h）	4.5
冷凝器冷却水进口温度/℃	27.5
除湿溶液流量/（m³/h）	3.6
再生溶液流量/（kg/s）	2
空气流量（混合溶液）/（m³/h）	2000
空气流量（LiCl溶液）/（m³/h）	2400
空气进口温度/℃	27~28
除湿溶液进口温度/℃	26~27
除湿再生循环流量/（kg/s）	0.3

参数	数值
热水流量/（kg/s）	1
热水温度/℃	70
冷却水流量/（kg/s）	1.5
冷凝器冷却水进口温度/℃	33
除湿溶液流量/（kg/s）	0.8
除湿再生循环流量/（kg/s）	0.1
空气流量/（kg/s）	0.6
空气进口温度/℃	30
空气进口含湿量/（g/kg）	18
除湿溶液进口温度/℃	30
再生溶液流量/（kg/s）	1
溶液-溶液换热器效能	0.7