Heat and Mass Transfer Model for Desiccant Solution Regeneration Process in Liquid Desiccant Dehumidification System

Abstract

In this paper, a simple model, but with high accuracy for a packed column liquid desiccant regenerator, to describe the heat and mass transfer process is developed. By lumping fluids’ thermodynamic properties and the geometric specifications as constants, two equations related with seven identified parameters are developed to predict the heat and mass transfer rate for solution regeneration processes in the regenerator. Commissioning information and the Levenberg–Marquardt method are employed to determine the unknown parameters. Compared with previous models, the presented model is simply constructed and accurate and requires no iterative computations while applied in predicting the heat and mass transfer rate once the parameters of the proposed model are determined. Experimental results demonstrate that the current model is effective to predict the performance of desiccant regeneration in the regenerator over wide working conditions. The proposed model promises to have wide application for real-time performance monitoring, optimization, and control for liquid desiccant regeneration.

Performance assessment of a membrane liquid desiccant dehumidification cooling system based on experimental investigations

“…In theory, desiccants which are classified into solid and liquid materials, remove moisture from an airstream through natural sorption process. Compared with the solid desiccant system, the liquid desiccant dehumidification (LDD) system has been a more promising and economical choice due to its flexibility in utilizing low-grade energy sources [5] and capability of independent humidity and temperature controls [6]. Moreover, the LDD system is capable to provide high quality supply air as liquid desiccants can filter the bacteria, microbial contaminations, viruses and moulds [7].…”

Experimental study of a membrane-based dehumidification cooling system

“…Compared with the solid desiccant system, the liquid desiccant system is more economical and flexible in utilization of low-grade energy sources 2 and efficient in providing high quality supply air with independent humidity and temperature controls 3 . Generally, the selection of a liquid desiccant depends on various operating parameters, such as boiling point elevation, energy storage density, regeneration temperature, thermophysical properties, availability and costs 4 .…”

Modeling and control of dehumidifier in distributed operating liquid desiccant dehumidification system

“…T are the inlet temperature of process air and the inlet desiccant solution. h R is the thermal resistance of the complete heat transfer procedure [69,78].…”

“…Heat transfer coefficient can be expressed as Eq. (A-9), with the heat transfer coefficients h , the packing diameter D, the fluid density  , velocity  , specific heat p c , viscosity  , and thermal conductivity as parameters [69,78]. (A-11)…”