Parametric Analysis of a Cross-Flow Liquid Desiccant Dehumidification System

International Journal of Research and Scientific Innovation (IJRSI) | Volume V, Issue VI, June 2018 | ISSN 2321–2705

Parametric Analysis of a Cross-Flow Liquid Desiccant Dehumidification System

Satwinder Singh¹, Vikas Gupta², Swarn Singh³

 ^{1, 2, 3}Department of Mechanical Engineering, Chandigarh Group of Colleges-College of Engineering, Landran (Punjab), India

Abstract- An experimental analysis of a packed bed liquid desiccant dehumidifier has been conducted. Calcium chloride was used as desiccant in the experiment. PVC packing with density of 150m2/m3 used to facilitate the interaction of liquid desiccant with air. The performance of the dehumidifier was measured in terms of moisture evaporation rate, specific humidity, change in humidity ratio, air outlet temperature under different air and desiccant parameters i.e air flow rate, air inlet temperature, desiccant solution flow rate, desiccant solution inlet temperature.

Keywords: Dehumidifier, Calcium chloride, Desiccant. Packing material height, Regenerator.

I. INTRODUCTION

Dehumidification of air is the process of removing the water vapor from the air. The atmospheric humid air consists of both sensible heat load and latent heat load. A conventional vapor compression system reduces the sensible heat by reducing the temperature of the air and reduces the latent heat load by cooling the air below dew point temperature. The major problem associated with vapor compression system is that it causes the depletion of ozone layer and it also requires a lot of electricity for its operation. Desiccant cooling systems have been considered as an alternative and effective method of controlling moisture content in supply air. Moisture from the air is removed in the desiccant systems due to difference in vapor pressure of desiccant and water vapor present in air. The vapor pressure of a desiccant is directly proportional to its temperature and inversely proportional to its concentration. A desiccant is a substance having low surface vapor pressure. When the desiccant is cool and dry, its surface vapor pressure is low and it can attract moisture from the air which has a high vapor pressure when it is moist. As the desiccant absorbs moisture it becomes wet and hot its surface vapor pressure increases and it will give off water vapor to the surrounding air. Vapor moves from the air to the desiccant and back again depending on the vapor pressure difference.. There are two types of desiccant dehumidification systems used in practice namely solid desiccant and liquid desiccant dehumidification system. But solid desiccant systems are not economical as they regeneration of the solid desiccant is a cumbersome method. Solid desiccant dehumidification uses a desiccant wheel through which a solid desiccant like silica gel circulates and it absorbs moisture from the air.

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