Research On Adsorption Of Wastewater From Polycarbonate Production

The gas-inducing reactors have the advantage of low energy consumption and no additional compressor is needed in the reactors.The gas-inducing reactors are more and more widely used in the hydrogenation and other industries.In recent years,the numerical simulation method has obvious advantages in the study of fluid flow and fluid mixing characteristics.In this paper,the CFD numerical simulation method is used to optimize the gas-inducing hydrogenation reactor.It provides important references for the design and optimization of the gas-inducing reactor.The main research contents and results are as follows:(1)In this paper,different turbulence models and other CFD model parameters are applied,and the simulation results are compared with the experimental datas to verify their accuracy.The RNG k-? turbulence model is chosen to simulate the turbulent flow in the gas-inducing reactor through the verification of Standard k-? turbulence model,RNG k-? turbulence model and Realizable k-? turbulence model.The gas-liquid,solid-liquid and liquid-liquid two-phase simulation method was verified to determine the applicable model of two-phase simulation: the steady-state calculation was adopted,using multiple reference frame method to simulate the blade rotation area,pressure and velocity coupling using SIMPLE algorithm,the second-order upwind difference scheme was adopted,the Eulerian model is used to solve the two-phase flow,Gidaspow model was adopted to solve the two-phase drag.(2)In this paper,the existing experimental reactor was modeled and simulated by the CFD model.The simulation results provide the basis for the optimal design of the reactor.The optimization work mainly from self suction blade type,the blade diameter,the distance between the paddle and the bottom of the reactor,the tube structure,double blade structure and feed locations.The optimization scheme of the reactor is obtained.The hollow blade is used as the self suction blade.The diameter of the self suction blade should be in the range of(0.23~0.3)T.The reactor should use the oval bottom structure.For the double blade,the PBTU 45 paddle should be used as the lower blade,the blade spacing shoud be in the range of(1~1.5)D,the diameter of the lower blade shall not be greater than the diameter of the upper blade.The best feeding position of the catalyst and DNT was determined through the unsteady simulation of solid-liquid and liquid-liquid in the reactor.The best feeding position of the catalyst particles is below the liquid level,and the best feeding position of DNT is below the upper blade.(3)In this paper,the geometric similarity amplification method and The scaling-up rule of equal to the self suction paddle linear velocity was used to optimized reactor up to 10 m3.The reactor model with heat exchange plates was established by CFD.The mixing performance of gas-liquid,solid-liquid and liquid-liquid in the reactor was simulated.The simulation results verified the reliability of the amplification process.