Study Of Pipeline Liquid Loading Infrared Monitoring Technology

The terrain of Puguang gas field is rather complicated,and the natural gas of it is transported by moisture gathering system. Liquid deposits in low-lying place, which will decrease gas transmission efficiency of the line, meanwhile, it also will cause corrosion inside pipeline, and high content of the carbon dioxide and hydrogen sulfide and will exacerbate corrosion. Therefore, monitoring liquid loading in pipeline, and taking suitable pigging process according to the liquid loading has important meaning to operating gathering and transportation pipeline of Puguang gas field safely and efficiently.This paper proposes the liquid and gas have enormous differences. so we can get the temperature gradient outside the wall of pipeline by heating or cooling the pipeline. Height of liquid loading will be got by analysing the temperature gradient. Based on the above principle, this article develops the infrared liquid loading monitoring system for two-phase stratified flow line through simulation of FLUENT software and experimental research. This system contains pipeline heating system, data acquisition system, data processing system. Thermal infrared imager gathers temperature gradient outside the wall, the image gathered will be transmitted to the computer through the USB, the height of liquid loading can be judged by liquid loading monitoring software. This system can measure the liquid loading outside the wall of the pipeline without destroying the structure of the pipeline or affecting the normal production of gas pipelines.This paper analyzes the influence of the height of liquid loading, heating time, gas velocity, heat dissipation after heating and other factors to temperature gradient outside the wall of pipeline by simulation of FLUENT software. Infrared liquid loading monitoring system was tested in the lab of yifu building in China university of petroleum. During the experimental process, we analysed the experimental data, conducted the error analysis timely and compared precision of infrared liquid loading monitoring system under static and dynamic conditions. This paper summarizes the influence of environment and human to the monitoring results. According to the experimental effect, we constantly adjusted the temperature and heating time of the heating membrane, modified the software in the liquid loading detection algorithm and perfected the infrared liquid loading monitoring system.Infrared liquid loading monitoring system was tested in Puggang gas field. This paper analyses the influence of topography, velocity of gas and pressure changes to the liquid loading. Results measured are basically the same with the results of simulation by OLGA software, and good results have been achieved.