Design And Economic Analysis Of Inlet Cooling System Driven By Waste Heat From Gas Turbine Of Gas Pipeline Pressure Station

Nature gas needs to be pressurized along the way in pipeline transportation.At present,80% of the compressor stations along the West-East Gas Pipeline in China are gas turbine-driven centrifugal compressor units.However,the operating performance of the gas turbine is affected by the ambient temperature.As the intake air temperature increases,the net power decreases and the heat consumption rate increases.Especially in summer,the output of the unit is seriously insufficient.At the same time,a large amount of waste heat can be utilized in the exhaust gas of the gas turbine.To solve this problem,a scheme for cooling the intake air of the gas turbine by using the absorption refrigeration system driven by the waste heat of the gas turbine exhaust gas is proposed in this paper.In this scheme,R124-DMAC is used as the refrigerant working fluid.The intake cooling demand of a gas turbine in Dingyuan Compressor Station of Anhui Province is taken as the engineering background.The thermal calculation of the whole cycle was carried out under the design conditions.In order to simplify the calculation process,the refrigeration cycle calculation software was written by VB.net,and the performance of the gas turbine before and after inlet air cooling was compared after the calculation was completed.The result shows that the net power of the unit increased by 12.7%,the mass flow rate of the inlet air increased by 6.0%,the heat consumption rate fell by 1.5% when the ambient temperature is 37°C and the inlet air is cooled to 22°C.The cooling effect is obvious.Then,the main parameters affecting the cycle performance are analyzed under two control strategies.It is found that the stability of the system performance is stronger under the condition of controlling the temperature of generator.Based on the calculated heat exchanger load and inlet and outlet parameters,the detailed structural design of each heat exchanger is carried out,and the COP of the whole system is 0.507.Finally,the refrigeration cycle process is simulated by Aspen Plus software,and the performance changes under variable ambient conditions are analyzed.It is found that the refrigeration system can still maintain a high coefficient of performance at a higher ambient temperature.Through the economic analysis of the scheme,the dynamic payback period of investment is 4.5 years,which fully demonstrates that the scheme is feasible and provides a powerful reference for the intake cooling of gas turbines in natural gas pressurization station.