Study On ORC-FP Waste Heat Recovery Similar System

With the continuous progress of industrial technology, non-renewable energy proportionin national economy is more and more big. Because of its long form and industrial demand isbig, the non-renewable resources reserves are dwindling. In order to alleviate the energyshortage, people will be attention to energy efficiency. In the process of industrial production,accompanied by a large amount of heat produced, although they energy grade is low but thequantity is huge, nearly40%of industrial energy consumption in our country is directly inthe form of heat emissions. So waste heat recovery will became a research focus in the future.Based on the above situation, this article introduce water as the working medium ofcommon Rankine cycle, analyzed the influence of the temperature and pressure on the cyclethermal efficiency, and then puts forward the ORC-FP waste heat recovery similar system. Inthis system, the organic working medium through the evaporator absorbs low grade wasteheat as working medium of high temperature and high pressure. Working medium of hightemperature and high pressure through the solenoid valve injects into the free pistonmechanism, which will convert low grade waste heat energy into high grade of mechanicalenergy.To study the cycle working medium in the Rankine’s system and found that when usingwet working medium as the cycle working medium, Rankine cycle thermal efficiency isincreased with the increase of the temperature of the working medium. While using dryworking medium and isentropic working medium as the cycle working medium, Rankinecycle thermal efficiency is decreased with the increase of the temperature of the workingmedium. Whether wet, dry or isentropic working medium as cycle working medium,Rankine cycle thermal efficiency will be increased with the increase of the pressure of theworking medium. Organic working medium can be high pressure steam at low temperature,so for the lower temperature energy use organic working medium has more advantages. Andby comparing the performance of different cycle working medium, finally decided the organic working medium R11as the working medium of ORC-FP waste heat recoverysimilar system.Use the GT-power to establish simulation model of ORC-FP waste heat recovery similarsystem. Through continuous debugging temperature, pressure and valve opening time,opening angle, got the following conclusions: when improve the temperature (T1), pressure(P1), or reduce pressure (P2) at the exit will increase the system’s cycle efficiency. Throughthe debugging process, found that when the temperature of the evaporator is430k, pressure is0.9Mpa; cold working medium temperature is320k, the pressure is0.9Mpa; The temperatureof working medium which had done is340k, pressure is0.4Mpa, Rankine cycle thermalefficiency is the highest, and can reach37.1%.Through the simulation model and related parameters, designed the free pistonmechanism, evaporator, condenser, working medium pump and other main components.Successfully establish ORC-FP waste heat recovery test system. The system uses thetemperature and pressure sensor to monitor the main parameters of system, uses resistancetype displacement sensor to monitor the piston displacement.During the testing process, found the following conclusion: with the increase of pressure,actual Rankine’s cycle efficiency rised first and then falled; Waste heat recovery efficiencyincreased; Total efficiency rised first and then falled. When the temperature of the evaporatoris390k, pressure is0.7Mpa; Cold working medium temperature is310k, the pressure is0.7Mpa；Working medium which had done temperature is340k, pressure is0.4Mpa, cycle totalefficiency is the highest, and can reach5.56%, the actual Rankine’s cycle efficiency is20.5%,and the waste heat recovery efficiency is27.1%.At the same time some problems were found in the system. Puting forward thecorresponding solutions, to lay a foundation to waste heat recovery.