Optimization Design And Experimental Study Of Evaporative Crystallization Unit

Nowadays,many factories produce a large amount of high-salt wastewater in the production process.If the materials in the high-salt wastewater can be recycled and reused,it will produce greater economic value.If these high-salt industrial wastewater is discharged directly without treatment,it will cause great pollution to the environment.Traditional membrane filtration because of the presence of various ions in water,these ions may produce less soluble sediments and scale the membrane surface,ultimately reducing the efficiency of wastewater treatment.In order to improve the stability of the equipment and the requirements for the treatment of high-salt wastewater with higher concentration,this paper adopts the method of atomization and evaporation of high-salt wastewater in high temperature environment.In this paper,the whole structure of the evaporative crystallization device is designed,the minimum heat dissipation area of the heat conduction disk required for evaporation is calculated theoretically,and the hollow shaft of the transmission part is calculated theoretically.In order to study the heat transfer characteristics of the heat conduction plate and establish the geometric model of the heat conduction plate,the structure of the heat conduction plate is optimized.The specific research contents are as follows:Firstly,the importance of wastewater treatment and the development of wastewater treatment at home and abroad are analyzed.The whole structure of evaporative crystallization device is designed,including the choice of driving mode,the choice of oil supply mode and the theory and structure design of key components.Secondly,the basic theory of CFD is described,and the whole operation process of thermal disk simulation is described in detail.The factors that may affect the surface temperature distribution of the heat conducting disc are analyzed and the internal oil passage of the heat conducting disc of the core device of the evaporative crystallization device is preliminarily designed.Thirdly,the simulation software is used to compare and analyze the different inlet positions,conditions and length-width ratios of the oil passage inside the heat conducting dish to determine the optimal structure of the oil passage inside the heat conducting dish.Finally,according to the simulation results of the software,a small prototype was produced to study the evaporation and crystallization law of the high-salt wastewater under different speeds,different temperatures,different ways of filling wastewater and different types of high-salt wastewater.To determine the optimal parameter matching;The simulation results show that under the same type of inlet pressure,outlet pressure and heat conduction oil,when the width of the oil channel is constant,the higher the height of the oil channel is,the larger the area of high temperature area is.When the oil channel is high,the wider the oil channel is,the larger the area of the high temperature area is.When the area of oil inlet is fixed,the wider it is,the larger the area of high temperature area will be.In the three connection modes of series and parallel connection,the parallel connection mode has the advantages of small pressure change,uniform pressure distribution,relatively more high temperature zone,small temperature change and relatively uniform temperature distribution.The heat conduction performance can be improved by using parallel oil circuit and increasing the width of oil circuit.The experimental results show that the efficiency of evaporative crystallization can be improved by increasing the rotating speed of the heat conducting disc in a certain range.The increase of temperature helps the evaporation crystallization process.The efficiency of evaporative crystallization is greatly affected by different ways of adding wastewater.Different types of high-salt wastewater also affect the efficiency of evaporation crystallization.