The use of mixtures partially miscible at low temperature in AHT, allows us to replace the distillation step by a simple settling operation which is less exergy destructive. Hence, a new machine called an absorption-demixing heat pump has been proposed.
A numerical calculation code has been developed to evaluate the performance of this cycle. Two different refrigerent/absorbent pairs (n-heptane–DMF and cyclohexane–DMSO) have been studied; the first being used in an experimental ADHT while the second is proposed for industrial purposes.
Thanks to simulation, the theoretical feasibility of such a cycle has been demon-strated. Moreover, significant temperature lifts (up to 50 °C) and thermal yields (up to 90% of the waste heat can be upgraded to a higher temperature level) can be obtained. The operating conditions leading to optimal performances has also been evaluated. Hence, an industrial application of the proposed cycle seems possible when waste heat is rejected at a temperature level corresponding to the evaporator's working temperature.
The operation of an experimental ADHT unit has allowed us to confirm the technical feasibility of such a cycle as well as the influence of the different operating parameters.