Performance Study On Tangential Flow Reflux Gas-Liquid Cyclone Tube

Coal-bed methane is a kind of unconventional nature gas stored in a state of adsorption in coal series strata. The method of water drainage with oil tube and gas production with bushing are adopted to exploit it. During the process of exploitation, mixing with impurities is inevitable. What’s more the impurities may cause corrosion and plugging in follow-up pipe and the equipment during the process of transportation. Therefore, it is very important to remove them.Based on previously presented research, this paper exploits efficient gas-liquid cyclone separation equipment--- Tangential flow reflux cyclone tube to meet the demand of exploiting coal-bed methane. The high-speed rotating of the gas-liquid mixture is generated by the guide vane within the new-type separator. The droplets have a greater centrifugal force due to the density difference between gas and liquid, leading them move into the wall and reach fluid outlet finally. Meanwhile, the clean gas is discharged from the exhaust pipe in the center of the separator. Making use of the flow characteristic of separator, the equipment adds a return pipe, backing the gas in the fluid outlet to central low pressure area resulting from the separator. The backing gas moves into the main separation zone, continuing separation process. Finally, the backing gas discharges from the exhaust pipe with the main airflow, completing separation process. On the one hand, the return pipe makes the gas in the outlet to flow, benefiting the drainage process. On the other hand, the reflux because of the low pressure in the central area can be eliminated, improving the efficiency and the ability to resist flow fluctuation.The inner flow flied and moving of particles are simulated through Fluent software combined with Reynolds Stress Model(RSM) and Discrete Phase Model(DPM). The investigation on the effects of structural and operating parameters on the performance of the equipment are conducted, providing guide for the design and optimizing of the separator.This paper machines the experimental prototype, designs the experimental process and establishes the platform. The characteristics of pressure drop and separation through cyclone tube under different conditions are studied by adjusting structural and operating parameters. Compared with the result of numerical simulation, the performance of the tangential flow reflux cyclone tube is verified.In order to verify the characteristics of the new-type cyclone tube by comparison, the author designs traditional three-dimensional guide cyclone tube. The numerical simulation and experimental comparison research are completed.Through the numerical simulation and experiment, the following results can be gotten: the separation efficiency of the new-type cyclone tube can reach more than 95%, the particle with a diameter more than 5μm can be eliminated effectively; the ability of separation and resisting flux fluctuation can be improved through the reflux pipe, at the same time, the pressure drop is decreased; the inner tangential velocity and the separation efficiency become higher when the height of the vane becomes lower, however the ability of resisting flux fluctuation decreases; the separation efficiency of the new-type equipment is improved greatly compared to the traditional one; the circumferential slit is suitable for the condition with a lower flux rate than the design, and the slits on the cylinder wall is suitable for the condition with a higher reflux rate than the design. Two kinds of drainage of the cyclone tube both have a wide range of flux tare.Synthesizing the results of numerical simulation and experiment, the tangential reflux cyclone tube has the characteristics of high efficiency, low resistance and ability of resisting flux fluctuation, meeting the demand of coal-bed methane gas-liquid separation.