| High temperature heat pump technology is one of effective measures for the improvement of energy quality.With the background,a further innovative study on traditional heat pump technology and application is needed.The goal of the innovative study is to improve energy grade greatly,use the low temperature heat for example low temperature heat of industrial emission,the air source in winter,solar energy,et al.as much as possible,and satisfy the energy demand in buildings and long-distance delivery of industrial waste heat for heating.The paper makes a theoretical analysis of high temperature heat pump working refrigerants,takes an experiment and a simulation of the high temperature heat pump,the outlet water temperature on condensing unit makes a new record of 130℃ and the temperature lift is 50℃.The high temperature heat pump is successfully applied to energy saving project.Based upon,the paper evaluates the economic efficiency and integrity of solar energy heat pump.In this paper,new refrigerant mixture BY-5 is conducted.It is environment friendly and has good performance at high temperature,the ODP,GWP and critical temperature are 0,800 and 155℃ respectively.The optimal operation temperature range is 110-130℃ and the one stage temperature lift is 50℃.Theoretical cycle performance of BY-5 and other high temperature refrigerants R11,R113,R114,R123,R21,R236 ea,R245ca and R245 fa are analyzed.The result shows that BY-5 has a good performance on pressure,heat capacity,COP and unit volume refrigerating capacity.An experiment study about the performance of high temperature heat pump is conducted,and the experiment result shows that it makes a good performance at high temperature level of 70 ℃-80℃ on evaporation unit and 110 ℃-130℃ on condensing unit.The corresponding condensing pressure,compression ratio and highest discharge temperature,COP are 2.71 MPa,4.44,132.37 ℃ and 2.54 respectively when the outlet water temperature of condenser reaches 130°C.When the temperature lift is less than 46℃,the COP is always higher than 3.0,the unit runs stably and reaches a good economic benefit.The experiment results are favorable to make the high temperature heat pump realize a popular use in the utilization of different low temperature heat sources.The presented system model performs good performance to evaluate the performance of the high-temperature heat pump by comparing the simulated and experimental results.The results show that the deviations of input power,heat capacity and COP are lower than 3.83%,5.39% and 3.55% respectively.Based on the system model,the analysis results indicate the high-temperature heat pump using BY-5 could attain an output temperature under 135℃ with good performance.An popularization and application about 130℃ high temperature heat pump is conducted in industry.The industrial stability and security of long term operation is tested in the energy saving project of distillation tower reboiler.The project reaches good economic benefit,environmental benefit and social benefit.A theory study is conducted about the replacement of traditional boiler heating system by solar energy heat pump to realize clean heating.The working refrigerants are analyzed at different temperature ranges.The economic efficiency and integrity of solar energy heat pump,air source heat pump,coal-fired boiler,gas-fired boiler and electric boiler are evaluated by annual cost evaluating method and fuzzy comprehensive evaluation.The result shows that the annual cost of solar energy heat pump is lower 2% than coal-fired boiler,the cost of electric boiler is highest and the economic efficiency is worst.The evaluation factors of air source heat pump and solar energy heat pump are 0.857 and 0.768 respectively,and they are higher than boiler heating system,and the solar energy heat pump is worth popularizing for its relatively high economic efficiency. |
