Droplets Recovery Efficiency And Mechanism For Gas-Liquid Flow

With the depletion of water resources,many innovative technologies of industrial water saving become urgent needs.Evaporation loss in wet cooling towers accounts for a larger share of circulating water loss.However,there is no effective way to solve this problem at present.In this dissertations,it was designed a mist eliminator which consisted of a cyclone separation unit,a diversion unit and a fiber coalescence filter unit based on cyclone separating and fiber coalescence technology and studied the water recovery efficiency.Through a series of experiments and numerical simulation,the optimum structural parameters and operating conditions were determined and the influences of these parameters on water recovery efficiency were studied.By means of numerical simulation,the experimental system was designed and built.Then,the water recovery efficiency was studied and the optimum structural parameters were gained.Finally the influence of operating conditions was discussed.The results showed that there were optimum parameters for overflow insertion depth and liquid seal height.In low liquid concentration,pressure drop of the cyclone separation unit was influenced by the swirl intensity and frictional resistance.In high liquid concentration,pressure drop of cyclone separation unit was influenced by the short cut flow.The water recovery efficiency of the mist eliminator had a slight increase and then a substantial increase with the increasing of the liquid concentration.The recovery efficiency first increased and then decreased with the increasing of the flow rate.The recovery efficiency decreased constantly with the increasing of the temperature.The recovery efficiency values of the mist eliminator were 6 % larger than those of the cyclone separate unit.On this basis,the influences on pressure drop were analyzed and compared under different conditions.Results indicated that in high liquid concentration,attention should be paid to frictional resistance of the fiber coalescence filter unit.In large variation processing capacity situation,drag reduction design of cyclone separation unit was needed.In low liquid concentration and small temperature variation situation,a drag reduction design of diversion unit was needed.