An experimental integrated absorption heat pump effluent purification system. Part I: operating on water/lithium bromide solutions

Abstract

The merits of single stage absorption heat pumps coupled to simple distillation for effluent treatment are discussed. An experimental integrated absorption heat pump effluent purification system (IAHPEPS) was built and operated with water–lithium bromide as a working mixture. This unit has been used to raise the temperature and hence, the vapour pressure of the impure water contained in one vessel, to the point where pure water vapour will distil from impure effluent solution (tap water or brine) and condense in a second vessel used to collect pure water. Pure effluent production rates of between 0.5 and 4.3 kg h −1 were obtained. The actual coefficient of performance ( COP A) and the heat pump effectiveness varied from 1.1 to 1.4 and 0.58 to 0.72, respectively. The results from the small scale system indicate the likely results from industrial scale units which could be operated with low quality heat such as waste heat, solar or geothermal resources.