Performance analysis and mixing ratio selection of mixed liquid desiccant for a dehumidification system

In the current study, the performance of the counterflow dehumidification test rig using wood shaving packing has been analysed. Wood shaving packing with the density 500 kg/m3 was used along with the CaCl2 desiccant with varying concentration. Mass flow rate of air was varied and the dehumidification performance parameters like moisture removal rate, dehumidification efficiency, coefficient of performance, change in relative humidity, change in the pressure and mass transfer coefficient were evaluated. Output parameters were compared with the commercially available cellulose packing with the wettability of 632 m2/m3. Results showed that, even though the performance of wood shaving packing is slightly less than the Celdek packing, performance of wood shaving is promising at 40% desiccant solution concentration. Maximum relative humidity difference, coefficient of performance and dehumidification efficiency obtained with wood shaving pad material were found to be 19%, 1.88 and 69.5%, respectively.

“…Jiang et al. 23 conducted experiments using mixing of liquid desiccants. LiCl and CaCl 2 mixed in the ratio 3:1 gave the best performance in terms of highest DE.…”

Section: Introductionmentioning

confidence: 99%

Assessment of process parameters in a dehumidification process using biomass-based wood shaving as a packing material

Salins

Reddy

2021

“…A mixture of LiCl and CaCl 2 was used to reduce the cost of LiCl and to improve the dehumidification performance. 10,25 It was observed that the cost of the desiccant was reduced by 30% for the same moisture removal capacity and also regeneration cost was reduced by 29%. It was also observed that by adding both PVOH and LiCl to silica gel, its performance was improved by 55% consistently as its moisture removal capacity was improved significantly.…”

Section: -11mentioning

confidence: 97%

Dehumidification performance improvement by using liquid desiccant blends – An experimental study

Parida

Kumar

2023

To minimize global warming and consumption of electricity, a desiccant-based air conditioning system has been proposed as a better alternative to control air humidity, compared to the conventional air conditioning system. In the present study, the performance of the hybrid desiccant was compared with the pure LiBr and KCOOH solution. Blends of LiBr and KCOOH at different weight ratios were used as desiccants. The performance of the system was compared based on its moisture removal rate and dehumidification effectiveness. The performance of the system increased with increasing desiccant flow rate, the concentration of the solute and the airflow rate. From the tested concentrations, the blend of 40% LiBr and 10% KCOOH concentration showed the highest MRR and dehumidification effectiveness among all blends of LiBr and KCOOH. From the study, it can be concluded that by using an optimized blend of LiBr and KCOOH as a desiccant in place of neat LiBr, the limitations of pure LiBr can be partly resolved without sacrificing much on the dehumidification performance.

“…Temperature and humidity independent control system based on the liquid desiccant dehumidification is a useful energysaving system to satisfy temperature and humidity demand separately. [2][3][4] However, in traditional liquid desiccant dehumidification system, the liquid desiccant solutions such as lithium bromide solution (LiBr), lithium chloride solution (LiCl), and calcium chloride solution (CaCl 2 ) absorb water vapour from the wet air in a direct contact mode. As a result, the liquid droplet entrainment and air pollution often happen, and it can cause corrosion in the ventilating pipe and air pollution.…”

Section: Introductionmentioning

confidence: 99%

Evaluation of membrane-based air pre-dehumidification for a capillary radiant air conditioning system

Wang

Yin

et al. 2020

The polyvinylidene fluoride hollow fibre membrane air dehumidification tests were carried out between the liquid desiccant solutions and the wet air. Three liquid desiccant solutions of LiBr solution (50%), LiCl solution (35%) and CaCl2 solution (40%) were tested under different wet air conditions. The results showed that all the membrane dehumidification processes were stable. The air moisture content in the outlet of the membrane was maintained as 6.5 g/kg (da)–8.2 g/kg (da) when the air moisture content in the inlet of the membrane was operated from 17.1 g/kg (da) to 32.4 g/kg (da). The dehumidification amount of LiBr solution (50%) and LiCl solution (35%) was more productive. On this basis, a membrane-based air pre-dehumidification process for the capillary radiant air conditioning system was built. Since the ideal dew point temperature range of the indoor air is below 14–17°C according to the cold supply water, all the air moisture content at the membrane outlet is much lower than that of the ideal dew point temperature range, which means non-condensing occurs in the capillary tube surface. The membrane-based air pre-dehumidification process can easily form an adaptive regulation process of humidity with the capillary radiant air conditioning system under different environmental parameters.