Variable effect absorption machine and process

High, intermediate and low pressure stages are provided in a thermal machine including sealed chambers permitting maintenance of respective pressures but permitting flow of vapor from one vessel to a second within a stage and providing for the flow of an absorbent solution among the vessels in different stages. The intermediate stage includes resorption and regeneration vessels which are thermally coupled, respectively, to a generation vessel and an absorption vessel in the high and low pressure stages, so that a variable fraction of the absorber heat may be transferred to the regenerator and of the resorber heat to the generator. The name Variable Effect refers to this variable internal heat transfer which permits the machine to adjust to a wide range of available heat source and heat rejection temperatures while maintaining high efficiency. Heats are accepted by and rejected from the generator and absorber over large ranges of temperature, which permits small pump and fan power and provides good utilization of the heat source and sink. Several versions of the machine, some including an evaporator and a condenser and others including a power convertor, and using fluids selected for each purpose, may be applied to heat pumping, chilling, temperature amplification, power production and desalination or other separation processes.