Mobile QR Code QR CODE : Korean Journal of Air-Conditioning and Refrigeration Engineering
Korean Journal of Air-Conditioning and Refrigeration Engineering

Korean Journal of Air-Conditioning and Refrigeration Engineering

ISO Journal TitleKorean J. Air-Cond. Refrig. Eng.
  • Open Access, Monthly
Open Access Monthly
  • ISSN : 1229-6422 (Print)
  • ISSN : 2465-7611 (Online)
Title A Study on the Reconcentration of Diluted Lithium Bromide Solution(LiBr-water) by the Vacuum Membrane Distillation
Authors Jung Gil Lee ; Oh Kyung Kwon
DOI https://doi.org/10.6110/KJACR.2020.32.8.367
Page pp.367-376
ISSN 1229-6422
Keywords 흡수제; 막증류 공정; 투과유량; 재-농축 공정; 염 제거율 Absorbent; Membrane distillation; Permeate flux; Re-concentration process; Rejection rate
Abstract The conventional absorption system which uses various absorbents, is widely applied during different process stages, such as with the dehumidification and cooling system etc., due to the possibility that the application will waste heat or other sustainable energy resources. However, the conventional absorption system requires the external heating process which is highly depending on the use of fossil fuels, to evaporate the water vapor from a diluted absorbent. Therefore, the membrane distillation process which can separate the water vapor from the solution from below boiling temperatures, is attracting attention as an advantageous and eco-friendly process with many applications to industries. In this study, we suggested the membrane distillation system is useful as the alternative re-concentration process of various absorbents. The performance evaluation and application feasibility test were conducted with experimentally and theoretically. The simulation results were well validated with the experimental results, and the maximum difference was noted as 5%. In addition, the investigation of the rejection rate and permeate flux of water vapor were conducted and measured at the various operating conditions. As a result, the permeate flux was 7.84 kg/.,h at the inlet feed temperature of 64.5℃, vacuum level of 4400 Pa, and the inlet volume flow rate of 0.9 L/min; and thus we proved with lab-scale experiment that the diluted LiBr solution can be concentrated from 53 wt% to 54 wt%. The possibility of the reverse flux which can be issued during the process was discussed in terms of the various solution concentrations and the operating conditions.