Performance Analysis On High-Efficient Gas-liquid Separator Working Under Negative Pressure

Liquid-Gas Cyclone separator is a kind of equipment that uses rotary motion of gas-liquidtwo-phase fluid to make the liquid particles separated from the gas flow by centrifugal force, and hasbeen widely used in the fields of environmental protection, petroleum, chemistry, and material. It hasa lot of advantages, such as simple structure, conveniently maintained, low manufacturing cost and soon. All these make the study of cyclone separator paid attention by the research personnel. A newstructure of two-stage gas-liquid separator working under negative pressure, which is available in aMechanical Vapor Recompression (MVR) evaporation system, was proposed to improve separatingefficiency of conventional gas-liquid separator and provide one more layer of protection tocompressor, by the means of Fluent12.0in computational fluid dynamics.Reynolds Stress Model (RSM) was used to simulate the gaseous phase because of the strongturbulence of gas, and the Lagrange equation-based Discrete Phase Model (DPM) was employed totrack the liquid particles’ motion and calculate the separation efficiency. In this study, separationcharacteristics such as pressure loss and separation efficiency of the improved scheme were analyzed,according to the simulation of the interior flow field and pressure field. Also the liquid particles’motion of different diameters was studied. On the base of research above, different structural andoperating parameters of gas-liquid separator was simulated, such as: different insertion depth ofoverflow pipe in the single-stage, using the3/4of doughnut baffle with different diameters, changingthe circle section of inlet pipe into rectangular section, the insrease of the second-stage size.According to the simulation results above, all the structural changes have made effect on thepressure loss and separation efficiency, but the increase of separation efficiency offen goes with theincrease of pressure loss. In order to measure the effect of the structural changes to separationproperty, we difine λ as comprehensive performance parameters. Made use of the results previous,there is an optimized programme. It could promote the separation efficiency of little liquid gasparticles effectively without obvious promotion of pressure loss by the numerical simulation methodwith the literature structure. The pressure loss is97.7Pa lower and the separation efficiency is1.6%higher than the literature structure.