Novel high temperature heat pump system with thermal cascade utilization

The device can realize thermal cascade utilization of industrial waste heat, and its working principle is as the following: the water is heated to high temperature by two stages, firstly it is heated to the intermediate temperature by CO2 at the supercritical state, and then is heated to high temperature by R152a at the subcritical state. Develops a system model, calculates and analyses the system performance. The results show that the cascade heat pump system has better performance than a single-stage system whether under the condition of same highest condensing temperature of heat pump system or the same temperature of water supply, and that the performance of cascade heat pump system is better than transcritical CO2 heat pump system under the same waste water source condition and same water supply temperature.