Experimental assessment of ammonia adiabatic absorption into ammonia–lithium nitrate solution using a flat fan nozzle

Abstract This paper presents the experimental evaluation of the adiabatic absorption of ammonia vapour into ammonia–lithium nitrate solution using a flat fan nozzle and an upstream single-pass subcooler. Data are representative of the working conditions of adiabatic absorbers in absorption chillers. The nozzle was located at the top of the absorption chamber, separated 205 mm from the bottom surface. The diluted solution mass flow rate was modified between 0.04 and 0.08 kg/s and the solution inlet temperature between 24.5 and 29.7 °C. The influence of these variables on the absorption ratio, mass transfer coefficient, outlet subcooling and approach to equilibrium factor is analysed in the present paper. A linear relation between the inlet subcooling and the absorption ratio is observed. The approach to equilibrium factor for the conditions essayed is always between 0.81 and 0.89. Mass transfer coefficients and correlations for the approach to equilibrium factor and the Sherwood number are obtained. Results are compared with other ones reported in the literature.

[1]  Alberto Coronas,et al.  Experimental study of an ammonia–water bubble absorber using a plate heat exchanger for absorption refrigeration machines , 2009 .

[2]  Alberto Coronas,et al.  Densities, Viscosities, and Heat Capacities of Ammonia + Lithium Nitrate and Ammonia + Lithium Nitrate + Water Solutions between (293.15 and 353.15) K , 2008 .

[3]  R. Lizarte,et al.  Evaluation of mass absorption in LiBr flat-fan sheets , 2009 .

[4]  Robert E. Wilson,et al.  Fundamentals of momentum, heat, and mass transfer , 1969 .

[5]  P. Riesch,et al.  Hydroxide absorption heat pumps with spray absorber , 1996 .

[6]  Carl Salter,et al.  Error Analysis Using the Variance-Covariance Matrix , 2000 .

[7]  W. Miller,et al.  The Correlation of Simultaneous Heat and Mass Transfer Experimental Data for Aqueous Lithium Bromide Vertical Falling Film Absorption , 2001 .

[8]  R. Ventas,et al.  On the recirculation of ammonia-lithium nitrate in adiabatic absorbers for chillers , 2010 .

[9]  M. Venegas,et al.  Thermodynamic study of multistage absorption cycles using low‐temperature heat , 2002 .

[10]  A. Coronas,et al.  Vapor−Liquid Equilibrium of Ammonia + Lithium Nitrate + Water and Ammonia + Lithium Nitrate Solutions from (293.15 to 353.15) K , 2007 .

[11]  M. Venegas,et al.  Boiling heat transfer and pressure drop of ammonia-lithium nitrate solution in a plate generator , 2010 .

[12]  Lester Haar.  Nbs/Nrc Steam Tables , 1984 .

[13]  Reinhard Radermacher,et al.  Absorption Chillers and Heat Pumps , 1996 .

[14]  M. Izquierdo,et al.  Spray absorbers in absorption systems using lithium nitrate–ammonia solution , 2005 .

[15]  Geydy Gutiérrez Urueta,et al.  Thermo-fluid dynamic evaluation of components in adiabatic absorption systems , 2009 .

[16]  M. Izquierdo,et al.  Heat and mass transfer during absorption of ammonia vapour by LiNO3–NH3 solution droplets , 2004 .

[17]  Domingo Santana,et al.  Modelling non-isothermal absorption of vapour into expanding liquid sheets , 2009 .

[18]  William A. Ryan.  Water absorption in an adiabatic spray of aqueous lithium bromide solution , 1994 .

[19]  R. Lizarte,et al.  Lithium bromide absorption machines: Pressure drop and mass transfer in solutions conical sheets , 2009 .

[20]  William M. Worek,et al.  Drop formation of swirl-jet nozzles with high viscous solution in vacuum-new absorbent in spray absorption refrigeration , 2008 .

[21]  M. Izquierdo,et al.  Experimental study on the adiabatic absorption of water vapor into LiBr–H2O solutions , 2005 .

[22]  Sung Hyun Kim,et al.  Experimental analysis of bubble mode in a plate-type absorber , 2002 .

[23]  Alberto Coronas,et al.  Absorption of organic fluid mixtures in plate heat exchangers , 2003 .

[24]  William M. Worek,et al.  Adiabatic water absorption properties of an aqueous absorbent at very low pressures in a spray absorber , 2006 .

[25]  A. Z. Santiago.  Transferencia de masa y calor en absorbedores adiabáticos con aplicación de la disolución nitrato de litio-amoniaco , 2011 .

[26]  B. D. Wood,et al.  Absorption of water vapour into falling films of aqueous lithium bromide , 1995 .

[27]  Siyoung Jeong,et al.  Falling-film and droplet mode heat and mass transfer in a horizontal tube LiBr/water absorber , 2002 .

[28]  J. Smith.  VERTICAL TUBULAR ABSORBERS FOR AMMONIA-SALT ABSORPTION REFRIGERATION , 2007 .