18 May 2017
The use of heat pumps for high temperatures in the industry is nowadays limited by refrigerant and by oil of the compressor. Another not always considered fact is sensible heat (sliding temperature of medium during heat flow) at source and sink (s&s). In many applications (e.g. district heating and drying processes) supercritical heat pump processes fix this at heat sink but with rarely inflexible temperature changes.
Flexible temperatures at s&s without any modifications, temperatures up to 150°C and sensible heat transfers at s&s are possible by using a Joule process. This kind of process works profitable only if the compression and expansion is realized with very high efficiencies (>99%). ecop realises these efficient pressure changes in a rotating system by using centrifugal force instead of high flow speed like in common turbo compressors. The COP depends, similar to two-phase heat pumps, on temperature spread but rarely on temperature level. Due sliding temperatures at s&s the potential will always be better than Clausius Ranking or super critical cycles. The used working gas, extracted from air, has no climate potential, isn’t flammable and is natural.
In summary the RHP has wide coverage of temperature, ecologically friendly working gas and higher COP as two phase circles. In industries waste heat is mostly sensible, so these are ideal circumstances for a RHP or just using it for higher temperatures. Measurements verified the realization of high COP for the considered applications.