Page Header

Experimental Investigation on the Performance of a Dehumidifier Constructed from a Water-to-Air Heat Exchanger Coated with Composite Desiccant of Mesoporous Silica Gel and LiCl

Jintana Srimuk, Surapong Chirarattananon, Pipat Chaiwiwatworakul, Adisak Nathakaranakule, Pattana Rakkwamsuk, Siriluk Chiarakorn


Thermal environment in buildings in hot climate is conditioned for comfort by air-conditioning that is energy intensive. Presently, most air-conditioning systems in Thailand and other countries in Southeast Asia use electricity-driven vapor compression systems to cool down the air to the set-point temperature. However, latent load due to condensation of air humidity forms a large part of the air-conditioning load. This paper presents the results of experiments on a dehumidifier constructed from a water-to-air heat exchanger coated with a composite desiccant of large-pore mesoporous silica gel and LiCl, regenerated by low-temperature hot water. Moisture removal capacity (MRC), dehumidification capacity (DC), thermal coefficient of performance (COPth), and an equivalent air conditioning load of dehumidification (EALD) are comparative quantitative parameters derived from experimental results and are studied in this research. The composite desiccant requires low-temperature water for regeneration and offers a higher rate of vapor adsorption and desorption that leads to a shorter required desiccant dehumidification cycle time. The results demonstrate that the dehumidifier is able to effectively reduce moisture in ventilation air and substantially reduces the cooling load of air-conditioning.


[1] L. Pérez-Lombard, J. Ortiz, and C. Pout, “A review on buildings energy consumption information,” Energy and Buildings, vol. 40, pp. 394–398, 2008, doi: 10.1016/j.enbuild. 2007.03.007.

[2] M. González-Torres, L. Pérez-Lombard, J. F. Coronel, I. R. Maestre, and D. Yan, “A review on buildings energy information: Trends, enduses, fuels and drivers,” Energy Reports, vol. 8, pp. 626–637, Nov. 2022, doi: 10.1016/j.egyr. 2021.11.280.

[3] S. Chiraratananon, “Climate influence on buildings and end-use energy requirements,” The Joint Graduate School of Energy and Environment (JGSEE), Bangkok, Thailand 2019.

[4] F. Zhang, Y. Yin, and X. Zhang, “Performance analysis of a novel liquid desiccant evaporative cooling fresh air conditioning system with solution recirculation,” Building and Environment, vol. 117, pp. 218–229, May 2017, doi: 10.1016/j. buildenv.2017.03.015.

[5] P. Vivekh, M. Kumja, D. T. Bui, and K. J. Chua, “Recent developments in solid desiccant coated heat exchangers – A review,” Applied Energy, vol. 229, pp. 778–803, Nov. 2018, doi: 10.1016/j. apenergy.2018.08.041.

[6] P. Wolkoff, “Indoor air humidity, air quality, and health-An overview,” International Journal of Hygiene and Environmental Health, vol. 221, pp. 376–390, 2018, doi: 10.1016/j.ijheh.2018.01.015.

[7] U.S. Environmental Protection Agency, “Moisture control guidance for building design, construction and maintenance,” 2013. [Online]. Available: http://

[8] Y. Zeng, J. Woods, and S. Cui, “The energy saving potential of thermos-responsive desiccants for air dehumidification,” Energy Conversion and Management, vol. 244, Sep. 2021, Art. no. 114520, doi: 10.1016/j.enconman.2021.114520.

[9] X. Zheng, T. S. Ge, Y. Yang, and R. Z. Wang, “Experimental study on silica gel-LiCl composite desiccant for desiccant coated heat exchanger,” International Journal of Refrigeration, vol. 51, pp. 24–32, Mar. 2015, doi: 10.1016/j.ijrefrig. 2014.11.015.

[10] K. S. Ramblad, P. V. Walke, and D. J. Tidke, “Solid desiccant dehumidification and regeneration methods – A review,” Renewable and Sustainable Energy Review, vol. 59, pp. 73–83, Jun. 2016, doi: 10.1016/j.rser.2015.12.264.

[11] A. Saeed and A. Al-Alili, “A review on desiccant coated heat exchangers,” Science and Technology for the Built Environment, vol. 23, pp. 136–150, 2017, doi: 10.1080/23744731.2016.1226076.

[12] M. S. A. Ramli, S. Misha, N. F. Haminudin, M. A. M. Rosli, A. A. Yusof, M. F. M. Basar, K. Sopian, A. Ibrahim, and A. Z. Abdullah, “Review of desiccant in the drying and airconditioning application,” International Journal of Heat and Technology, vol. 39, pp. 1475–1482, Oct. 2021, doi: 10.18280/ijht.390509.

[13] M. M. Abd-Elhady, M. S. Salem, A. M. Hamed, and I. I. El-Sharkawy, “Solid desiccant –based dehumidification systems: A critical review on configurations, techniques, and current trends,” International Journal of Refrigeration, vol. 133, pp. 337–352, Jan. 2022, doi: 10.1016/j.ijrefrig. 2021.09.028.

[14] Y. Jiang, T. S. Ge, R. Z. Wang, and L. M. Hu, “Experimental investigation and analysis of composite silica-gel coated fin-tube heat exchangers,” International Journal Refrigeration, vol. 51, pp. 169–179, Mar. 2015, doi: 10.1016/j. ijrefrig.2014.11.012.

[15] L. M. Hu, T. S. Ge, Y. Jiang, and R. Z. Wang, “Performance study on composite desiccant material coated fin-tube heat exchangers,” International Journal of Heat and Mass Transfer, vol. 90, pp. 109–120, Nov. 2015, doi: 10.1016/j. ijheatmasstransfer.2015.06.033.

[16] Y. D. Tu, R. Z. Wang, and T. S. Ge, “Moisture uptake dynamics on desiccant-coated watersorbing heat exchanger,” International Journal of Thermal Science, vol. 126. pp. 13–22, Apr. 2018, doi: 10.1016/j.ijthermalsci.2017.12.015.

[17] C. Channoy, S. Maneewan, S. Chirarattananon, and C. Punlek, “Development and characterization of composite desiccant impregnated with LiCl for thermoelectric dehumidifier (TED),” Energies, vol. 15, Feb. 2022, Art. no. 1778, doi: 10.3390/en15051778.

[18] H. H. Wang, T. S. Ge, X. L. Zhang, and Y. Zhao, “Experimental investigation on solar powered self-cooled cooling system based on solid desiccant coated heat exchanger,” Energy, vol. 96, pp. 176–186, Feb. 2016, doi: 10.1016/j. energy.2015.12.067.

[19] Y. Zhao, Y. J. Dai, T. S. Ge, H. H. Wang, and R. Z. Wang, “A high-performance desiccant dehumidification unit using solid desiccant coated heat exchanger with heat recovery,” Energy and Buildings, vol. 116, pp. 583–592, Mar. 2016, doi: 10.1016/j.enbuild.2016.01.021.

[20] S. Chai, X. Sun, Y. Zhao, and Y. Dai, “Experimental investigation on a fresh air dehumidification system using heat pump with desiccant coated heat exchanger,” Energy, vol. 19, pp. 306–314, Mar. 2019, doi: 10.1016/

[21] C. X. Jia, Y. J. Dai, J. Y. Wu, and R. Z. Wang, “Experimental comparison of two honeycombed desiccant wheels fabricated with silica gel and composite desiccant material,” Energy Conversion and Management, vol. 47, pp. 2523–2534, Sep. 2006, doi: 10.1016/j.enconman.2005.10.034.

[22] M. Sultan, I. El-Sharkawyb, T. Miyazaki, B. B. Saha, and S. Koyama, “An overview of solid desiccant dehumidification and air-conditioning,” Renewable and Sustainable Energy Reviews, vol. 46, pp. 16–19, Jun. 2015, doi: 10.1016/j.rser. 2015.02.038.

Full Text: PDF

DOI: 10.14416/j.asep.2023.05.003


  • There are currently no refbacks.