Experimental study of a thermochemical compressor for an absorption/compression hybrid cycle Articles uri icon

publication date

  • September 2012

start page

  • 297

end page

  • 304

volume

  • 97

International Standard Serial Number (ISSN)

  • 0306-2619

Electronic International Standard Serial Number (EISSN)

  • 1872-9118

abstract

  • Energy Solutions for a Sustainable World - Proceedings of the Third International Conference on Applied Energy, May 16-18, 2011 - Perugia, Italy An experimental study of a thermochemical compressor with ammonia-lithium nitrate solution as working fluid has been carried out. This compressor incorporates a single-pass adiabatic absorber and all the heat exchangers are of the plate type: absorber subcooler, generator and solution heat exchanger. The thermochemical compressor has been studied as part of a single-effect absorption chiller hybridized with an in-series low-pressure compression booster. The adiabatic absorber uses fog jet injectors. The generator hot water temperatures for the external driving flow are in the range of 57-110 degrees C and the absorber pressures range between 429 and 945 kPa. Experimental results are compared with a numerical model showing a high agreement. The performance of the thermochemical compressor, evaluated through the circulation ratio, improves for higher absorber pressures, indicating the potential of pressure boosting. For the same circulation ratio, the driving hot water inlet temperature decreases with the rise of the absorber pressure. The thermochemical compressor, based on an adiabatic absorber, can produce refrigerant with very low driving temperatures, between 57 and 70 degrees C, what is interesting for solar cooling applications and very low temperature residual heat recovery. Efficiencies and cooling power are offered when this hybrid thermochemical compressor is implemented in a chiller, showing the effect of different operating parameters.

keywords

  • hybrid absorption/compression chiller; ammonia-lithium nitrate; adiabatic absorber; plate heat exchangers; thermochemical compressor; solar cooling