Performance of a solar-regenerated liquid desiccant ventilation pre-conditioning system

A solar-regenerated liquid desiccant ventilation pre-conditioning system has been proposed for use in hot and humid climates. The system aims to dehumidify the ventilation air which is the major source of latent load. A heat exchanger is used to cool the dehumidified air instead of typical evaporative cooling to maintain the dryness of the air. The use of solar energy at the regeneration process and cooling water from a cooling tower makes the system more passive. The simulation procedure for the proposed system has been presented. By inputting the climatic data and the physical parameters of all equipments, the operating parameters at each equipment and the performance parameters of the system can be evaluated. The simulation procedure is demonstrated by showing the daily profiles of the operating and performance parameters on a typical day as well as investigating the influence of the selected operating parameters on the system performance. The results suggest that the most influential parameters are solar radiation, ventilation rate, and desiccant solution concentration. The balance between the water removed at the dehumidifier and that evaporated at the regenerator needs to be considered to maintain uniform performance during continuous operation.

[1]  Y. K. Yadav.  Vapour-compression and liquid-desiccant hybrid solar space-conditioning system for energy conservation , 1995 .

[2]  G. Grossman,et al.  A packed bed dehumidifier/regenerator for solar air conditioning with liquid desiccants , 1980 .

[3]  S. A. Sherif,et al.  A feasibility study of a solar desiccant air-conditioning system. Part II : Transient simulation and economics , 1999 .

[4]  Palanichamy Gandhidasan,et al.  A simple analysis of an open regeneration system , 1983 .

[5]  Wasim Saman,et al.  Modelling and performance analysis of a cross-flow type plate heat exchanger for dehumidification/cooling , 2001 .

[6]  Moustafa M. Elsayed,et al.  Effectiveness of heat and mass transfer in packed beds of liquid desiccant system , 1993 .

[7]  Abdulghani A. Al-Farayedhi,et al.  Evaluation of heat and mass transfer coefficients in a gauze-type structured packing air dehumidifier operating with liquid desiccant , 2002 .

[8]  Tsair-Wang Chung,et al.  Predictions of moisture removal efficiencies for packed-bed dehumidification systems , 1994 .

[9]  F. Kreith,et al.  Principles of heat transfer , 1962 .

[10]  Palanichamy Gandhidasan,et al.  Calculation of Heat and Mass Transfer Coefficients in a Packed Tower Operating With a Desiccant-Air Contact System , 1986 .

[11]  Palanichamy Gandhidasan,et al.  Effectiveness of moisture removal for an adiabatic counterflow packed tower absorber operating with CaCl2-air contact system , 1988 .

[12]  W. Beckman,et al.  SOLAR ENGINEERING OF THERMAL PROCESSES Second Edition , 2009 .

[13]  D. Goswami,et al.  Study of an aqueous lithium chloride desiccant system: air dehumidification and desiccant regeneration , 2002 .

[14]  J. R. Howell,et al.  Preliminary performance evaluation of a hybrid vapor-compression/liquid desiccant air conditioning system , 1987 .

[15]  Sabah A. Abdul-Wahab,et al.  Air dehumidification by triethylene glycol desiccant in a packed column , 2004 .

[16]  Palanichamy Gandhidasan.  A simplified model for air dehumidification with liquid desiccant , 2004 .

[17]  Wasim Saman,et al.  Modeling and performance of a forced flow solar collector/regenerator using liquid desiccant , 2002 .

[18]  Palanichamy Gandhidasan.  Simple analysis of a forced flow solar regeneration system , 1982 .

[19]  D. Yogi Goswami,et al.  Effectiveness of Heat and Mass Transfer Processes in a Packed Bed Liquid Desiccant Dehumidifier/Regenerator , 2000 .

[20]  Pai-Lu Wang,et al.  Experimental Study of a Forced Convection Solar Collector/Regenerator for Open-Cycle Absorption Cooling , 1994 .

[21]  Wasim Saman,et al.  An experimental study of a forced flow solar collector/regenerator using liquid desiccant , 2002 .

[22]  James E. Braun,et al.  An effectiveness model of liquid-desiccant system heat/mass exchangers , 1989 .

[23]  A. Kakabaev,et al.  Absorption solar refrigeration unit with open regeneration of solution , 1969 .

[24]  Edward Allan Vineyard,et al.  Parametric analysis of variables that affect the performance of a desiccant dehumidification system , 2000 .

[25]  Wasim Y. Saman,et al.  DESIGN AND EVALUATION OF A SOLAR REGENERATOR FOR A LIQUID DESICCANT SYSTEM , 1988 .

[26]  John W. Mitchell,et al.  A hybrid solar desiccant cooling system , 1985 .

[27]  W. Beckman,et al.  Solar Engineering of Thermal Processes , 1985 .

[28]  P. M. Ku.  ASME winter annual meeting , 1978 .

[29]  D. Y. Goswami,et al.  Experimental Study of the Heat and Mass Transfer in a Packed Bed Liquid Desiccant Air Dehumidifier , 1998 .

[30]  Pradeep Kumar,et al.  Modelling of the thermal behaviour of a solar regenerator for open-cycle cooling systems , 1989 .

[31]  R. K. Collier,et al.  The analysis and simulation of an open cycle absorption refrigeration system , 1979 .

[32]  J. Duffie,et al.  Cooling with solar energy , 1961 .

[33]  B. D. Wood,et al.  Evaporation Rate Model for a Natural Convection Glazed Collector/Regenerator , 1990 .

[34]  Palanichamy Gandhidasan.  Performance analysis of an open-cycle liquid desiccant cooling system using solar energy for regeneration , 1994 .

[35]  B. Nimmo,et al.  An economic analysis of a solar open cycle desiccant dehumidification system , 1995 .

[36]  H. F. Zhang,et al.  Numerical simulation and theoretical analysis of heat and mass transfer in a cross flow liquid desiccant air dehumidifier packed with honeycomb paper , 2004 .

[37]  Refrigerating.  ASHRAE handbook of fundamentals , 1967 .

[38]  L. G. Harriman.  The basics of commercial desiccant systems , 1994 .

[39]  Gershon Grossman,et al.  Performance simulation of regenerating type solar collectors , 1983 .

[40]  Moustafa M. Elsayed,et al.  Parametric study of a packed bed dehumidifier/regenerator using CaCl2 liquid desiccant , 1993 .

[41]  George O.G. Löf,et al.  Performance of a Solar Desiccant Cooling System , 1988 .

[42]  Ahmed M. Hamed,et al.  Theoretical and experimental study on the transient adsorption characteristics of a vertical packed porous bed , 2002 .

[43]  Omar M. Al-Rabghi,et al.  Proposed energy-efficient air-conditioning system using liquid desiccant , 1996 .

[44]  R. E. Treybal.  Mass-Transfer Operations , 1955 .

[45]  Sabah A. Abdul-Wahab,et al.  Predictions of moisture removal rate and dehumidification effectiveness for structured liquid desiccant air dehumidifier , 2004 .

[46]  Abdulghani A. Al-Farayedhi,et al.  Solar regeneration of liquid desiccants suitable for humid climates , 1994 .

[47]  Manuel R. Conde,et al.  Properties of aqueous solutions of lithium and calcium chlorides: formulations for use in air conditioning equipment design , 2004 .

[48]  A. Ertas,et al.  Properties of a new liquid desiccant solution—Lithium chloride and calcium chloride mixture , 1992 .