Numerical Simulation And Experimental Study On Gas-liquid Two-phase Flow Of Curved-plate Dehydration Precipitation

In this paper, the bent plate dehydration equipment in wet electrostatic precipitation is systematically studied. The dust and mechanical water from gas can produce serious harm to gas-steam combined cycle power plant operation(CCPP),so that the mechanical water content is required to be less than 5mg/m3.The flow field in curved plate dehydration equipment is analyzed theoretically,established the droplet phase, gas phase and liquid membrane phase differential equation of motion. Through numerical simulation and experimental study on curved-plate dehydration precipitation, computing gas-liquid flow in the precipitation and simulation the droplet trajectories in the flow field, experiment gets the best structure parameters of dehydration efficiency and reduced pressure loss, the law of gas phase influenced by structure parameters and the empirical formula of critical velocity.The influence law of the performance of the curved plate dehydration equipment caused by blade spacing, velocity and average particle size is known through orthogonal experiment: The dehydration efficiency and the pressure loss of the bent plate dehydration equipment with the blade spacing increasing distance is reduced; In the range of critical velocity, the dehydration efficiency and the pressure loss with the velocity increasing is induced. Changing the particle size of the inlet gas, dehydration efficiency with the particle size increasing is induced when the the particle size is less than 190μm. But the pressure loss almost not change with the change of the droplet. The optimum gas velocity is 3.7 m/s,the space between the curved-plates is 16~20 mm, the optimized particle size of water spray is 150~190 μm, the best ratio of liquid and gas is 0.2~0.25 L/m, and the amount of water is0.890 m3/h. Based on all those factors above, highest dewatering efficiency and least resistance can be obtained.New equipment devised has such advantages as higher dewatering efficiency, less pressure loss, easy manufacture, etc. In addition, the curved plate dehydration equipment can reduce mechanical water in the gas to 5 mg/m3, which has great influence on widespread use and optimal design of curved-plate dehydration equipment both in theoryand practice.