The Design Of Gas Turbine Waste Heat Recovery System Based On Natural Gas Transmission Pipeline

This paper taking the waste heat of gas turbines which belong to Hongliu contact compressor station of the first,second and the third East-west line as research object,for the purpose of recycling waste heat to capacity,designs a organic Rankine cycle(ORC)waste heat recovery system,the main points of this paper are as follows:The comparison of different ORC systems shows that in the case of no more than the critical temperature the evaporation temperature for the system is a favorable factor for the basic ORC system.Compared to the basic ORC system the efficiency of the and expander output power of the ORC system with recuperator are greatly improved.Compared to the efficiency 18.7% of the basic ORC system the efficiency of the ORC system with superheater increases to 19.18%,but if the degree of superheat is more than a certain value,increasing the degree of superheat is not helpful to increase the system efficiency.According to the above principles,the key parameters of the system are as follows: evaporation temperature 229.3 ?,the degree of superheat 20.7 ?,and heat recovery temperature 146?.Based on C5 a set of parameters of Hongliu compressor station waste heat power station is obtained.The preheater,evaporator,superheater and regenerator in the system is designed by HTRI heat exchanger design software,and the detailed parameters of the system are obtained.Based on the process parameters of ORC waste heat recovery system and the detailed parameters of the device,the waste heat boiler in the whole system is divided into preheater,evaporator and superheater according to the working flow of the thermal system.A dynamic simulation model was established on MATLAB/simulink simulation platform by using modular modeling method to study the changing conditions of the system.The results show that the generation capacity of the ORC system in the spring and autumn,summer and winter are respectively 10377337.7W,10505638.8W,8467565.8W,which is affected by the difference between the gas transmission volume and the atmospheric temperature.Due to the low thermal efficiency in winter,it is recommended that part of gas turbine exhaust gas of the first West to East line be bypassed for the heating of the station in winter.It is suggested that hot oil should not be less than 145.3Kg/s to avoid high temperature damage to the expander in the design case;It is recommended that when the load of gas turbine of the second,thirdWest-East Gas Pipeline both reach 90% the amount of cyclopentane in the system should be increased to avoid damage to the evaporator.