Thermodynamic balancing of the humidification dehumidification desalination system by mass extraction and injection

Abstract Humidification dehumidification (HDH) is a promising technology for small scale seawater desalination and has received widespread attention in recent years. The biggest roadblock to commercialization of this technology is its relatively high energy consumption. In this paper, we propose thermodynamic balancing of the humidifier or the dehumidifier through mass extraction and injection as a potential means of reducing the energy consumption of these systems. Balancing minimizes the entropy generation caused by imbalance in driving temperature and concentration differences. We outline a procedure to model the system, using on-design component variables, such that continuous or discrete extraction and/or injection of air from the humidifier to the dehumidifier or vice versa can be analyzed. We present an extraction profile (mass flow rate ratio versus non-dimensional position) in the dehumidifier and the humidifier for attaining close to complete thermodynamic reversibility in an HDH system with a 100% effective humidifier and dehumidifier. Further, we have examined in detail the effect of having finite-sized systems, of balancing the humidifier versus the dehumidifier, and that of the number of extractions.

[1]  Karan H. Mistry,et al.  Optimal operating conditions and configurations for humidification–dehumidification desalination cycles , 2011 .

[2]  M. T. Chaibi,et al.  Water desalination by humidification and dehumidification of air: State of the art☆ , 2001 .

[3]  John H. Lienhard,et al.  Entropy generation minimization of combined heat and mass transfer devices , 2010 .

[4]  Majid Amidpour,et al.  Improvement of Solar Humidification-dehumidification Desalination Using Multi Stage Process , 2011 .

[5]  A. Bejan.  Entropy Generation Minimization: The Method of Thermodynamic Optimization of Finite-Size Systems and Finite-Time Processes , 1995 .

[6]  Ronan K. McGovern,et al.  High-temperature-steam-driven, varied-pressure, humidification-dehumidification system coupled with reverse osmosis for energy-efficient seawater desalination , 2012 .

[7]  John H. Lienhard,et al.  Thermodynamic analysis of humidification dehumidification desalination cycles , 2009 .

[8]  Shaobo Hou,et al.  Two-stage solar multi-effect humidification dehumidification desalination process plotted from pinch analysis , 2008 .

[9]  John H. Lienhard,et al.  Entropy generation in condensation in the presence of high concentrations of noncondensable gases , 2012 .

[10]  G. G. Stokes.  "J." , 1890, The New Yale Book of Quotations.

[11]  J. Lienhard,et al.  Erratum to Thermophysical properties of seawater: A review of existing correlations and data , 2010 .

[12]  John H. Lienhard,et al.  ENERGY EFFECTIVENESS OF SIMULTANEOUS HEAT AND MASS EXCHANGE DEVICES , 2010 .

[13]  M. A. Darwish,et al.  Experimental and theoretical study of a humidification-dehumidification desalting system , 1993 .

[14]  R. Hyland,et al.  Formulations for the thermodynamic properties of dry air from 173.15 K to 473.15 K, and of saturated moist air from 173.15 K to 372.15 K, at pressures to 5 MPa , 1983 .

[15]  Refrigerating.  ASHRAE handbook and product directory /published by the American Society of Heating, Refrigerating and Air-Conditioning Engineers, Inc , 1977 .

[16]  Ronan K. McGovern,et al.  Performance limits of zero and single extraction humidification-dehumidification desalination systems , 2012 .

[17]  Hendrik Müller-Holst,et al.  SOLAR THERMAL DESALINATION USING THE MULTIPLE EFFECT HUMIDIFICATION (MEH)-METHOD , 2007 .

[18]  Hendrik Müller-Holst.  Mehrfacheffekt-Feuchtluftdestillation bei Umgebungsdruck , 2002 .

[19]  M. McLinden,et al.  NIST Standard Reference Database 23: Reference Fluid Thermodynamic and Transport Properties-REFPROP, Version 8.0 , 2007 .

[20]  D. P. Sekulic,et al.  Fundamentals of Heat Exchanger Design , 2003 .

[21]  John H. Lienhard,et al.  The potential of solar-driven humidification–dehumidification desalination for small-scale decentralized water production , 2009 .

[22]  W. Wagner,et al.  The IAPWS Formulation 1995 for the Thermodynamic Properties of Ordinary Water Substance for General and Scientific Use , 2002 .

[23]  John H. Lienhard,et al.  Thermal Design of Humidification– Dehumidification Systems for Affordable Small-Scale Desalination , 2012 .

[24]  Ronan K. McGovern,et al.  Variable Pressure Humidification Dehumidification Desalination System , 2011 .

[25]  W. Marsden.  I and J , 2012 .