Working pressures on performance of ultrasonic atomization liquid desiccant dehumidification system

doi:10.11949/0438-1157.20191134

Abstract

Abstract:

The effect of working pressures on the performance of the liquid desiccant dehumidification system was studied in this work. The ultrasonic atomization liquid desiccant dehumidification system (i.e., UADS) was taken as the prototype while a model based on the mass balance, the energy balance of the atomized solution dehumidification process was employed to simulate the performance. It was found that the dehumidification performance of the UADS system increases significantly with the rise of working pressure. In particular, when the air inlet temperature climbs, the facilitating effect of raising working pressure on the dehumidification efficiency becomes more significant. Meanwhile, a more significant promoting effect from the working pressure on the moisture removal rate was also presented with the rise of the inlet humidity ratio of the airstream, while its effect on improving the dehumidification effectiveness was weakening. In addition, the dehumidification performance tends to be more stable with the rise of the working pressure and less affected by the inlet conditions of the airstream. This study may help in clarifying and promoting the performance of the liquid desiccant dehumidification system under different working pressures.

Key words: solution, absorption, working pressure, dehumidification performance, stability

摘要：

基于溶液除湿热质传递过程中所遵循的质量平衡、能量平衡模型，以超声雾化溶液除湿系统（UADS）为例，探讨了在不同空气处理温度、湿度下，系统运行压力对除湿性能的影响。结果表明：随着运行压力的升高，UADS系统的除湿性能显著改善。特别是在所处理空气入口温度较高时，提升系统运行压力对除湿效率的提高作用更加显著。同时，当所处理空气的含湿量较大时，提高运行压力对系统除湿速率的增幅明显，而对除湿效率的改善作用减弱。此外，当除湿系统在较高压力下运行时，其除湿效率受所处理空气入口温湿度变化而产生的波动减小，系统性能稳定性显著改善。所得结果可对溶液除湿系统的高效、稳定运行提供积极参考。

关键词: 溶液, 吸收, 运行压力, 除湿性能, 稳定性

CLC Number:

TU 834.9

Zili YANG, Caiyun GAO, Feiran GONG, Xuyun YU, Yun YU, Tianxun CAI. Working pressures on performance of ultrasonic atomization liquid desiccant dehumidification system[J]. CIESC Journal, 2020, 71(S1): 129-135.

杨自力, 郜彩云, 龚斐然, 余旭芸, 余赟, 蔡天逊. 运行压力对超声雾化溶液除湿系统性能的影响[J]. 化工学报, 2020, 71(S1): 129-135.

Figures/Tables 9

Fig.1 Schematic diagram of process of dehumidification

Table 1 Parameters of equation for specific capacity of aqueous solutions of LiCl[21]

A	B	C	D	E	F	G	H
1.43980	-1.24317	-0.12070	0.12825	0.62934	58.5225	-105.6343	47.7948

Fig.2 Schematic diagram of UADS[16]

Fig.3 Experimental validation of prediction model

Table 2 Operating parameters

空气流量/

(kg·s^-1)

空气温度/

℃

空气含湿量/

(g·kg^-1)

溶液流量/

(kg·s^-1)

溶液温度/

℃

溶液浓度/

雾化液滴半径/

μm

1.0

0.5

Fig.4 Effects of working pressure on dehumidification performance at different air inlet temperatures

Fig.5 Effects of working pressure on dehumidification performance at different air inlet humidity

Fig.6 Effects of air inlet temperature and humidity on dehumidification effectiveness at different working pressures

Fig.7 Effects of air inlet temperature and humidity on moisture removal rate at different working pressures

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