Performance Evaluation of a Desiccant Dehumidifier with a Heat Recovery Unit

Abstract

Abstract:In order to effectively increase the drying rate and reduce the energy consumption, a dryer which reduces the air humidity at the dryer inlet using desiccant and regenerates the desiccant by recovering waste heat using a heat pipe heat exchanger was developed in this study. Both the adsorption rate and desorption rate of the dryer were measured at several ambient temperatures ranging from 15 • C to 35 • C, relative humidity levels of air ranging from 20% to 85%, and airflow rates ranging from 30 m 3 /h to 150 m 3 /h. The results showed that the adsorption rate in an environment of high relative humidity of air was 4.89 times higher than that of low relative humidity of air at 15 • C. Moreover, the difference in adsorption rate between two given relative humidity of air increased as the ambient temperature decreased. The specific energy consumption estimated with both energy consumption during desorption and the desorption rate indicated that the energy consumption was 8.27 kJ/g H 2 O without using recovered heat, while the energy consumption was 4.77 kJ/g H 2 O using recovered heat at 130 • C.

Energy performance and climate dependency of technologies for fresh water production from atmospheric water vapour

“…Internal heat recovery increases the dehumidifier performance. 101,102 Wang et al reached an SY water of 0.84 L kW −1 h −1 by using LiCl enclosed in an active carbon felt matrix as adsorbent and an electric heater for the discontinuous desorption stage. 95 The high efficiency can be explained by the humid conditions under which this excellent performance was achieved in combination with an efficient heater.…”

Thermal Performance of a Low-Temperature Heat Exchanger Using a Micro Heat Pipe Array

“…In these studies, the exhaust temperature of the gases is generally over 90 • C [3]. Yang et al proposed a novel heat pipe-based desiccant device [4]. Galindo et al analyzed some models based on an experimental Organic Rankine Cycle (ORC) in a turbocharged 2.0 L gasoline engine, using the waste heat recovery, and they found that the effect was good [5].…”

A Universal Mathematical Methodology in Characterization of Materials for Tailored Design of Porous Surfaces

“…The quality of energy supplied to the adsorption system is critical as it is dictated by the unique interaction of the adsorbent-adsorbate pair and the adsorption energy sites that are available to the adsorbate molecules. In adsorption dehumidification, the quality and amount of energy required for regeneration depends upon adsorption energy sites that capture adsorbate molecules from the mainstream (Yang K. S. et al, 2017 ; Yang W. et al, 2017 ; Burhan et al, 2018b ).…”