Study On The Law Of Mixing In The Process Of Natural Gas Pipeline Production

At the period of natural gas pipeline rapid development, being put into production safely and economically has become an important issues focused on by the pipeline company. Nowadays, environment pollution problem increases prominently, nitrogen replacement in the process of production is not only to meet safety requirements, but also consider how to save the nitrogen consumption, and reduce the volume of emissions reasonably, so as to improve the safety and economy of pipeline operation, and reduce environmental pollution as much as possible.Analyzing the pipe production technology at home and abroad, and analyzing the different displacement method. According to Sichuan to east gas pipeline company production data, summary analyzing the "line" after the station first adaptability of production process, and puting forward the exist problems of Sichuan to east gas company in the process of pipe production that the mixed gas and the amount of nitrogen is too large.Using FLUENT software, and on the basis of CFD and turbulence simulation theory, reasonably determining the mathematical model of nitrogen replacement and boundary conditions, and dynamic simulating of the factors that influence of mixed gas length in the process of production,and coming up to the influence of different factors on the impact of the trend of gas mixing length.According to the characteristics of the long-distance pipeline terrain change, using FLUENT software to analyze the gas mixture rules of downhill section, and drawing the conclusions:the trend of the mixed gas segment length is that ascent stage mixed gas length is less than the horizontal line stage, and mixed gas length decreases with the increase of angle, and the displacement time increases with the increase of angle; the mixed gas length of downhill phase segment is greater than the horizontal line, and mixed gas length increases with the increase of angle, and the displacement time decreases with the increase of angle.According to different terrain conditions, researching the length of mixed gas calculation amount method.Through the adaptability analysis of different nitrogen injection quantity calculation, drawing out a lookup table of the injection capacity of nitrogen, which is convenient for field staff to determine the injection capacity of nitrogen quickly and accurately.Through investigation of Sichuan to east gas pipeline production data, combining with the numerical simulation results, verifying and analyzing the gas mixing rules and the calculation formula of injection capacity of nitrogen, then analyzing the adaptability of he calculation formula of injection capacity of nitrogen of this study,and providing guidance on making plans for pipeline production.