Study On Application Of Flue Gas Type Double-effect Lithium Bromide Absorption Heat Pump In Wastewater Treatment Plant

Sewage treatment plants are usually places where waste heat resources are abundant.Especially in recent years,the concept of "cogeneration" is put forward and its application in sewage plant development,relative to the past energy efficiency,can be said to have achieved very good results,but in the use of waste heat is still exist much waste problems.Therefore,this paper studies,analyzes and summarizes on how to make reasonable and full use of sewage plant waste heat resources,and finally puts forward a new method of reclaiming waste heat resource by using "double-effect lithium bromide absorption heat pump" technology.Firstly,based on the analyzed of the heat transfer and mass transfer of the heat exchanger,the physical model and mathematical model of each heat exchanger are established based on Aspen Plus software and the theoretical basis of heat and mass transfer.Secondly,a specific example was modeled,simulated and analyzed by using Aspen Plus software.The simulation results were in good agreement with the theoretical results.The results showed that the simulating accuracy of Aspen Plus software was good.Then,based on the Aspen Plus software simulation and the orthogonal table obtained by SPSS software,the application of the double-effect lithium bromide absorption heat pump system in the wastewater treatment plant was simulated and optimized.The factors influencing the performance of the double-effect lithium bromide absorption heat pump system were analyzed.The total heat transfer area of the unit and the system performance parameters.Finally,by establishing the life cycle cost mathematical model of the double-effect lithium bromide absorption heat pump unit,the unit life cycle cost LCC and the unit average annual cost EUAC are taken as the optimization objective function,The optimal combination of heat transfer and temperature difference of waste heat recovery by using "double-effect lithium bromide absorption heat pump" is determined.The results show that under the condition of the heat source price,the heat pipe price and the discount rate,when the temperature difference of the evaporator is 2?,the temperature difference of the condenser is 3.5?,and the temperature difference of the absorber is 2?,The flue gas outlet temperature of 150?unit average annual operating costs EUAC minimum,about 48.7 million.