Process Design Of Intelligentized Mini-Scale Power Generation Technology By Pressure Energy Of Natural Gas Pipeline Network

With its advantages of clean and economy,natural gas(NG)is widely used in China,which results in the persistent acceleration of pipeline network construction.There is no doubt that the intelligent pipeline network construction plays an essential part in the improvement of safety,reliability and economy of pipeline network,the premise of which is the full-coverage electricity supply for intelligent pipeline network.However,most of the small sites of pipeline network suffer from severe power shortages.To meet the need of the intelligent pipeline network construction and management upgrade of gas industry,the process design of intelligentized mini-scale power generation system by pressure energy of NG pipeline is proposed in the article considering the characteristic of the small sites of pipeline network.Firstly,based on the conditions of small sites in NG pipeline network,four types of mini-scale power generation technology were respectively designed for pressure regulator station,pressure regulator box,high-pressure valve chamber and low-pressure valve chamber according to their different pressures,flows and available planning space.In addition,selection and structural design of the key equipment for four types of technologies were demonstrated.The power generation technology for pressure regulator station generates power by a fluid motor which is connected to a bypass of the original pipeline.As to pressure regulator box technology,an impeller is built into the pipeline which is driven by NG and then generates power.To enhance the safety,a combination of an impeller and a magnetic coupling is used in high-pressure valve/chamber type and low-pressure valve/chamber technology.The difference between these two technologies is that equipment are installed in the bypass for the former and inside the original pipeline for the later,respectively.Next,based on some pressure regulator station with a flow rate of 6000 Nm~3/h and inlet pressure of 0.8 MPa and mini-scale power generation technology by pressure energy,the project was designed to meet the requirements of power of devices in the station,small space occupation and low investment cost.The project includes designation of generation process and intelligence,key equipment selection and process elastic analysis and technology economy,proving the feasibility of the project.At last,an experiment system of mini-scale power generation technology by pressureenergy of NG pipeline is established,the results of which demonstrated that the output power increases with increasing volume flow rate and inlet pressure,and important indicators of the system met the requirement primely under the constant working condition.The system can stably generate 228W direct current power of 24 V when the volume flow rate of NG is 35Nm~3/h,the inlet temperature is 15°C and the inlet pressure and outlet pressure are 0.8 MPa and0.1 MPa respectively.The mini-scale power generation system by pressure energy meets the power need of small sites of NG pipeline network.