Recently, heat pump were watched with keen interest since they are useful to save energy because they can recover much energy from lower heat sources using small amounts of energy. In this case both mechanical energy and chemical energy can be used as said small amount of energy.Hydraulic control valves In a case of so called compression type heat pump using mechanical energy, not only is the so called coefficient of performance (C.O.P.) limited but also temperatures of lower heat source and temperatures of higher heat source (from which energy is recovered) are limited since there are limitations on safety or heat stability of the heating medium and on mechanical strength of the system.

On the other hand, in a chemical heat pump utilizing reversible endothermic and exothermic reactions, the temperature ranges of the lower heat source and the higher heat source in the chemical heat pump system can be broadened, by selecting the raction system.

For example, when a reversible reaction, (e.g. a secondary alcohol decomposing to a ketone and a hydrogen) is utilized, the temperature of the lower heat source is about 55

2011-12-30

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