Analysis Of Flow Field Characteristics And Investigate On Dehydration Performance Of Supersonic Cyclone Separator

In the process of gathering and transportation,the acid hydrate formed by water,heavy hydrocarbons,CO₂ and H₂S in natural gas will block and corrode pipelines and equipment,which limits the long-distance transportation of natural gas.Therefore,natural gas must be dehydrated before gathering and transporting.Supersonic cyclone separator is a new type of dehydration device,which integrates the functions of condensation and separation,and has broad application prospects.In this paper,for safety and economic reasons,the flow field characteristics and dewatering performance of supersonic cyclone separator were studied by using humidified nitrogen instead of natural gas.The main components of supersonic cyclone separator were designed by using aerodynamics,thermodynamics and other related theories,using 13.2 MPa saturated nitrogen as the research medium.Based on the structure design of the device,the effect of pressure loss on the dehydration performance of supersonic cyclone separator was studied experimentally.The flow field distribution,droplet path,condensation liquefaction process and factors affecting gas liquefaction process and gas-liquid separation process in supersonic cyclone separator were analyzed by numerical method.On the basis of experimental investigate and numerical analysis,the following conclusions can be drawn.?1?The structure of supersonic nozzle had a certain influence on the spontaneous condensation process of gas.The humidity distribution in the nozzle was independent of the structure of the contraction segment,but was related to the structure of the expansion section.The humidity at the nozzle outlet depended on the nozzle outlet diameter.?2?The location of shock wave determined the separation performance of supersonic cyclone separator.With the increase of the pressure loss ratio,the shock wave position moved to downstream of the supersonic nozzle,which led to the isentropic expansion of gas in the supersonic nozzle to a greater extent,which was conducive to the improvement of the refrigeration performance of the supersonic nozzle.?3?The droplets with different diameters had different centrifugal forces at the same position,and then had three typical trajectories in the supersonic cyclone separator.Droplet diameter,gas-liquid area ratio and number of blades had significant effects on separation efficiency.?4?When other conditions were the same,increasing the inlet pressure,decreasing the temperature and increasing the over saturation of the inlet gas would cause the Wilson point to move forward at the supersonic nozzle,and the nucleation rate and the number of droplets would increase.?5?In the experiment of keeping the inlet pressure unchanged and adjusting the outlet pressure of supersonic cyclone separator,when the pressure loss was 50.76%,the dew point dropped to 15 K;when the pressure loss ratio was 20.92%,the dew point dropped to 7 K.Increasing pressure loss meant that the minimum temperature of the gas in the nozzle decreased,which increased the condensation depth of the gas and thus improved the dehydration efficiency.