Study On Concentration Technology Of Salty Wastewater Based On Cyclone Separator

As a kind of separation equipment,cyclone separator has simple structure,no moving parts,less investment in manufacturing and installation,simple operation and maintenance,moderate pressure,low power consumption,low operation and maintenance cost,high separation efficiency and no special requirements of physical properties of materials,and stable performance.In this paper,the traditional spray evaporation technology is improved by the negative pressure environment of cyclone separator,and a high-salt industrial wastewater treatment equipment with simple structure,large processing capacity and low energy consumption is developed.The numerical calculation method was used to calculate and analyze the wall surface evaporation of the gas-liquid cyclone separator,collector and cyclone separator.Finally,a model size building experimental platform for cyclone separator is selected for experimental research.Based on the summary of the research work of scholars at home and abroad,this paper determines the turbulence model and numerical calculation method for numerical simulation of cyclone separator and wall evaporation.The simulation results of the cyclone separator are basically consistent with the Hoekstra experimental results.The validity of the discrete phase(DPM)model,the Reynolds stress model(RSM)turbulence model,the velocity inlet and pressure outlet boundary conditions,and the calculation of the solver settings are verified.The simulation results are compared with the experimental data of Bartolomei.It is concluded that the ratio of the wall temperature distribution between the simulated value and the experimental value is basically consistent with the experimental data.The rationality of the evaporationcondensation model and its solver setting is verified.The change of working conditions affects the separation performance of the cyclone separator,and the droplet size at the inlet,the inlet speed,the inlet liquid content and the operating pressure are studied.As the inlet speed and droplet size increase,the centrifugal force on the droplet increases,and the droplets are easily captured and separated by the wall of the separator;the separation efficiency of the gasliquid cyclone separator depends on the inlet liquid content.Increased and significantly increased,the total pressure drop remained stable and then gradually increased with the increase of the liquid content of the inlet;the separation efficiency and total pressure drop of the cyclone separator decreased with the increase of the pressure at the outlet.The length of the cylindrical section and cone section of the cyclone,the depth of the overflow pipe,the diameter of the overflow pipe,the inclination of the inlet pipe,the inclination angle of the inlet pipe,and the width of the liquid peristaltic skirt were analyzed at an inlet speed of 18 m/s.The tangential velocity and axial velocity of each structural dimension model change with the radial position.The pressure drop and separation efficiency of each model were analyzed under the conditions of inlet speed of 16.1,18,25 m/s and the typical particle size of the droplets of 10 ?m.According to the comprehensive analysis results,the pressure drop and separation efficiency of the cyclone separator change nonlinearly with the change of the size of each structure.Through the simulation calculation of the three blade bottom diameter models near the overflow nozzle of the cyclone separator,it is found that the diameter of the bottom end can not be smaller than the diameter of the underflow tube,and then the size of the blade group is determined.According to the influence of different temperature on the wall,evaporation is obtained on the wall of the cyclone separator.When the wall temperature is low,the evaporation of the liquid is mainly affected by the temperature.After the wall temperature rises,the pressure becomes the main factor affecting the evaporation of the liquid.Five models of different inlets and outlets were used for the analysis of the collector.Considering the two aspects of pressure drop and collection efficiency,the tangential inlet form is better than the intermediate inlet form,and the top outlet form is superior to the side outlet form,which further improves the cone lengthening performance,and finally determines the tangential inlet top outlet.(cone lengthening)program.Two experiments were carried out on the improved structure of the cyclone separator,namely the separation efficiency experiment before and after the addition of the blade group structure in the cyclone separator and the evaporation efficiency experiment at the cyclone separator.Comparing the blade group structure with the bladeless group structure,the separation efficiency of the cyclone separator is increased by 4.6% after adding the blade group structure;the temperature of the secondary heating device at the cone end of the cyclone separator is set to 100 °C,110 °C,120 °C,Experiments were carried out at 130 ° C and 140 ° C.It was found that the experimental values of the evaporation efficiency were basically consistent with the curves of the simulated values,showing a tendency to increase first and then decrease.In this paper,the variation of separation performance of cyclone separator under different working conditions and different structure sizes is studied.The variation of separation performance after adding the blade group structure in the cone section of cyclone separator,and the temperature of the cone section under different wall temperatures Evaporation was carried out for analysis.The experimental platform was built to conduct experimental research on the separation efficiency experiment before and after the addition of the blade group structure in the cyclone separator and the evaporation efficiency experiment at the cyclone separator.The thesis has 63 pictures,23 tables,and 81 references.