Study On The Separation Performance Of Vane Mist Eliminator

Fiber bed, wire mesh, vane demister, and wave-plate mist eliminators are commongas-liquid separation device. Among all these eliminators, vane mist eliminator iswidely used in process industries due to cost effective and space saving. Separationefficiency and pressure drop are the most important parameters to evaluate theperformance of these devices. Yet so far, there is still not any simple theoreticalcalculation method which could be used for vane demister’s performance assessmentin common. Under this circumstance, it is very necessary to bring out a simplecalculation equation for engineering application to estimate vane mist eliminator’sefficiency.In this paper, a simple structure vane mist eliminator has been introduced. Atheoretical expression of the mist eliminator efficiency is obtained based on thehorizontal mixed flow and axial piston flow theory. The accuracy and applicability ofthis theoretical model are validated using computational fluid dynamic (CFD) method.Using particle transport multiphase flow model and RNG k-ε turbulence model in theCFX module of ANSYS12.1, numerical simulation of wave-plate mist eliminator’sinternal gas-droplet two phase flow field and separation efficiency was conducted.The results of simulation have been used in further modifying the theoreticalcalculation expression. Experimental research has been carried out to check whetherthe numerical simulation method is perfect. The experimental apparatus wasconsisting mainly of a spray-generation circuit and an air carrier circuit. The testsection was composed of a1m-long stainless steel duct and a rectangular organicglass housing which contains the vane mist eliminator. The basic measurementprinciple of experiment is mass conservation.Although there are still some deviations between numerical simulation andtheoretical formula, the theoretical formula can still estimate the effects of differentgeometries and operation conditions on the separation effciency of vane misteliminators very well, and the error is within the permissible scope of15%. Thismodel can also be used to design or optimize system design.