Improvement And Optimization Of The Water Source Heat Pump System Based On Condensing Heat Recovery

Generally, the places with the use of air conditioning or heat pump units for cooling and dehumidification, such as hotels, hospitals, foot baths, saunas, etc., all have demands for living hot water. Currently, the cold and heat source program for building is to design air conditioning systems and living hot water systems separately. This design program will lead to a result: On the one hand, it contributes to thermal pollution of the surroundings,causes the waste of heat. On the other hand, it also needs to consume a large amount of energy on the boiler or electric heater to heat living hot water to meet the health needs. Obviously, there has been no reasonable allocation to make full use of energy. The technology of condensation heat recovery,that is, partly or wholly collecting the heat which is discharged through the condenser in the air conditioning. This technology will greatly increase the utilization rate of energy and reduce environmental pollution at the same time.This study aims to simulate the hourly air conditioning cold and hot load of the water source heat pump system in a complex building of a hospital by using De ST, an energy simulation software. The living hot water load of the building is calculated in detail. Condensing heat provide by the original water source heat pump units is calculated. The feasibility of condensing heat recovery in air conditioning system is summarized. Two reconstruction programs of condensing heat recovery is proposed base on this architecture: direct condensing heat recovery program and indirect condensing heat recovery program.For direct condensing heat recovery program, the refrigeration cycle before and after the transformation is simulated and analyzed by CYCLEPAD, a thermodynamic cycle simulation software. The relationship between parameters that affect the stable operation of the units, such as condensing temperature and evaporation temperature is analyzed. Design and selection are made for the modified equipments, such as the heat recovery equipment, the pump and other equipments. Finally, operation is made for some aspects after transformation, such as the hot water temperature and the unit operation control.For indirect condensing heat recovery program, heat recovery units in heat pump systems and other equipments are designed in detail. Then, combined with the operation of the original water source heat pump units, hot water supply program in summer, transitional season and winter is provided. Finally, an optimization of units operation control is planned.In the end, two kinds of condensing heat recovery programs and traditional gas boiler hot water supply methods before transformation are compared and analyzed, this paper also calculate the initial investment, operating costs and return on investment, and provides reference for the condensing heat recovery technology in the practical engineering application.