Parametric study of operating and design variables on the performance of a membrane-based absorber

Abstract

A microchannel H2O-LiBr absorber using a microporous membrane is simulated.• Sensitivity of cooling capacity/absorber volume to various parameters is evaluated.• Parameters to be optimised at the design stage of the absorber are identified.• Porosity, pore diameter, solution channels depth and membrane thickness are crucial.• Vapour pressure and solution inlet temperature and concentration should be optimised.

Experimental performance comparison of three flat sheet membranes operating in an adiabatic microchannel absorber

“…For a given membrane and experimental conditions, the absorption rate increases with the solution mass flow rate. This result is consistent with the previous models of Asfand et al [7], Venegas et al [9] and the experimental results of Isfahani et al [12].…”

“…According to the theoretical study of Ali and Schwerdt [1], an increase of the membrane thickness from 50 to 127 m in a membrane with a pore diameter of 0.45 m, reduces the absorption rate by 55%. The model of Venegas et al [9] gives, for the same change in thickness, a 45% decrease.…”

“…[12] and Venegas et al [9] with the solution mass flow rate. As the mass transfer resistance is obtained by normalizing the absorption rate with the pressure potential, the dependance with the pressure potential appears to be less pronounced.…”

“…The model of Venegas et al [8,9] was used to stablish the relative importance of the main membrane parameters such as pore diameter, porosity and thickness (which were varied in ranges of 0.3-1.5 m, 50-90% and 50-210 m) in the design of a microchannel absorber. This model was used later in Venegas et al [10] to compare two different configurations of microchannel membrane-based absorbers: in one case using cooling water to extract the absorption heat (non-adiabatic) and, in the other one, considering a novel adiabatic configuration.…”

Role of Membrane Technology in Absorption Heat Pumps: A Comprehensive Review

“…The absorption rate increased with the following operating conditions: High solution mass flow rate, high vapor pressure, and high inlet LiBr concentration. Another numerical studies [ 114 , 115 ] were carried out to analyze the geometric features and the operating conditions in a membrane desorber integrated by microchannels. The aqueous LiBr solution was considered.…”