Energy efficiency analysis of a multifunctional hybrid open absorption system for dehumidification, heating, and cooling: An industrial waste heat recovery application

Rising energy consumption for heating, dehumidification, and cooling applications has created a scientific gap to develop new hybrid energy systems which can utilize the available waste heat or renewable energy resources. In this study, a new multifunctional hybrid open absorption system is proposed to utilize the waste heat from moist air or flue gases to supply hot water for heating and to dehumidify the ambient air for further industrial or space cooling applications at the expense of any external heat source for regeneration requirement. This multifunction system consists mainly of two open column absorbers (primary and secondary), condenser, regenerator, heat exchangers and Maisotsenko cycle based dew point indirect evaporative cooler. The secondary absorber recovers the latent heat from moist gas and the primary absorber dehumidifies the ambient humid air for air-conditioning or other cooling applications. Absorbed water vapors from the absorbers are condensed to get the recovered water by transferring the vapor's latent heat to the circulating water which can be used for heating applications. The thermodynamic and process models of this system are developed to analyze its performance in detail. The effects of important inlet parameters are studied on different performance parameters and the results highlight that the system is capable to provide 176.9 kW heating capacity at the thermal coefficient of performance of 2.223 with heat recovery efficiency of 87.1%. Moreover, this system can recover 115.2 kg/h water in the form of condensate with recovery efficiency of 76.36% and cooling capacity of 9.873 kW can be achieved at system design specifications.

Automated summary

A new multifunctional hybrid open absorption system is proposed to utilize waste heat for heating, dehumidification, and cooling applications. The system can provide heating capacity, recover water, and achieve cooling capacity efficiently through waste heat recovery and heat exchange.