Numerical Optimization Simulation Of HAC High Efficiency Clarifier

With the rapid increase of water pollution and the increasing demand for water quality,how to improve the treatment effect of water treatment structures has attracted much attention.The high efficiency clarifier is based on micro-vortex coagulation technology and shallow pool theory.The scrambling level of the flocculating chamber in the clarifier is improved by adding the grid plate,and the baffle is installed in the separation chamber to increase the export volume and reduce the drug consumption level,so as to realize the high efficiency and energy saving of the purification process and improve the purification quality of emission reduction.A new sewage purification system with automatic hydraulic control mechanism is developed.The system has the advantages of small occupation,low investment,simple operation and low cost.The study of micro-vortex mesh flocculation in AC high efficiency clarifier is not enough,the design has no corresponding specification guiding parameters,and depends on engineering experience,and there is no corresponding theoretical basis.This study takes FLUENT software as the analysis and processing tool.A numerical simulation model was built to simulate and analyze the HAC high efficiency clarifier,and the operating conditions of the flocculation chamber were calculated and analyzed.The flocculation effect was evaluated by the turbulent kinetic energy dissipation rate and vortex velocity gradient G'.The distribution rule of G value in flocculating area is analyzed.The flow velocity of grid plate,the inlet velocity of clarifier,the position of grid plate in flocculating chamber,and the grid plate layer of flocculating chamber are studied.The influence of parameters such as the number of inlet slope and slope angle on flocculation effect.The findings are as follows:1)the distribution of G value between two adjacent grid plates in the first flocculating chamber of the tank has a certain rule: the maximum G value at the grid plate,the strongest effect of water flow disturbance,and the decrease of G value and the weakening of water disturbance effect when the grid plate is gradually removed.(2)the first flocculating chamber of the tank body decreases with the decrease of the net velocity,and the best flocculation effect is when the flow rate of the firstflocculating chamber is 0.26-0.28m/s.3)the optimal inlet velocity distribution of the high efficiency clarifier is between0.45-0.5m/s and the optimum inlet diameter can be calculated back by the optimal inlet velocity.When the grid plate is distributed near the middle of the flocculation chamber,the flocculation effect is the best.5)when the number of grid layers in the flocculation area is 5 layers,the hydraulic flocculation conditions are optimal.6)when the slope angle of the inlet slope is 50 degrees,the optimal hydraulic flocculation effect is achieved.