Performances des mélanges LiBr-H2O, LiCl-CaCl2-H2O et LiCl-MgCl2-H2O en pompe à chaleur et en réfrigération
Written by sctunisie no commentsThe operation of absorption cycles involves at least two fluids: a solvent and a solution. Although other couples are studied, the only ones that are used in practice for almost all the applications are LiBr-H2O and NH3-H2O couples. These mixtures present some disadvantages such as pressure levels, corrosion, toxicity, high cost, as well as risk of crystallization for LiBr-H2O. The objective of this work is to analyze LiCl-MgCl2-H2O and LiCl-CaCl2-H2O mixtures. It consists of studying the effect of the various operating variables on the performance coefficient, the released power, the energy expenditure and the storage density both in heat pump and refrigeration modes. The obtained results show that LiCl-MgCl2-H2O presents interesting characteristics such as a coefficient of performance which can reach 1.95 in heat pump and 0.9 in refrigeration, a heat pump effect which can exceed by 100 % the LiBr-H2O one and a lower cost than this last. As for the storage density that translates the effective volume of the machine is favourable to the conventional mixture LiBr- H2O in heat pump and to LiCl-MgCl2-H2O mixture in refrigeration. Hence a technico-economic study is required in order to replace the LiBr-water system by one of the other two less expensive mixtures.
B. Chaouachi, S. Gabsi, A. Ben Brahim
absorption, heat pump, refrigeration, performance
Pages 237-250
