Filtration And Separation Of Particles From Natural Gas Pipelines

In today’s energy production,natural gas is considered to be an important and necessary feedstock in many industries.Aiming at the problems of unstable performance and high operation cost of gas-liquid coalescence separation filters used in the process of natural gas long-distance pipeline transportation,this paper systematically summarizes the latest research progress in filtration materials,filter structure,and separation performance test methods at home and abroad.The resistance and separation efficiency of four kinds of filtration materials were measured in a standard experimental apparatus.By investigating the pressure drop,saturation,and quality factors,the effects of filtration speed and layer number on the separation performance were compared,and the agglomeration and separation mechanisms of fine droplets were revealed from the point of view of liquid saturation distribution and droplet existence form.According to the performance test standard of filter material,the separation performance of glass fiber filter material was measured by an aerodynamic particle size spectrometer and a liquid aerosol generator.The research results provide theoretical support for the structural design,operation,and maintenance of a high-pressure natural gas filter.The experimental gas was pretreated and purified by a high efficiency air filter（HEPA filter）.Dioctyl Sebacate（DOS oil of density=0.9119 kg/m³）was selected for the experimental liquid,the liquid aerosol generator was used for atomization,and the mass flow controller was used to keep the flow rate and pressure constant.Liquid aerosols are mixed with clean air in the mixing chamber and guided to vertically installed effective filtration materials with a diameter of 163 mm.The captured droplets flow into the liquid collector,and the filtered gas is purified and discharged into the atmosphere through an efficient air filter.In this thesis,the ways of producing aerosols and the transportation process of liquid in the process of gas-liquid coagulation filtration are discussed in detail investigating pressure drop（ΔP）in filter media.It is found that the content of liquid in micro-filtration media will increase due to the change of liquid content.The liquid saturation in the filter medium was observed by a microscope,and the visual images of the filter medium channel and liquid distribution were obtained.By measuring the aerosol concentration in the upstream and downstream air flow of the filter material,the filtration efficiency(₁1)))was calculated,and the separation performance of the filter was evaluated comprehensively by using the quality factor().These findings provide support for optimizing the performance of the filter fiber and producing a high-efficiency and low-resistance filters.