Simple Mixed Refrigerant Heat Pump (10ethane/90propane)

Heat pumps transfer heat from a low-temperature heat source to a higher-temperature heat sink and are widely used for space and water heating, industrial heat recovery, and simultaneous heating and cooling. Mixed refrigerants can offer thermodynamic advantages over pure fluids, and zeotropic mixtures in particular may exhibit temperature glide during phase change, which can be beneficial in some heat-exchanger applications. This example demonstrates a simple vapor-compression heat pump using a mixed refrigerant consisting of 10% ethane and 90% propane. The refrigerant evaporates by absorbing heat from a water stream, thereby cooling the water, before being compressed to a higher pressure and temperature. It then transfers heat to a second water stream, is expanded through a valve, and returns to the evaporator to complete the cycle.