Application Of PSO-ELM And CFD In MBR Membrane Fouling

Membrane Bioreactor(MBR)is a new type of highly efficient wastewater treatment and reuse process that combines biodegradation with efficient membrane separation.It utilizes membrane separation device to effectively trap activated sludge and macromolecular organic substances in the biochemical reaction tank to replace the secondary sedimentation tank.Compared with the traditional process,MBR has a rather good solid-liquid separation characteristics,high MBR biomass,low sludge yield,good effluent quality and small area.At present,the application of intelligent simulation model in MBR flux prediction is paid more and more attention.Domestic and foreign scholars have done a great deal of research work on the influence of sludge concentration,operating pressure and other parameters on membrane fouling in the process.Based on classical mathematics,many mathematical models of membrane fouling have been established to simulate the changes of membrane flux and other parameters Effect of membrane pollution.However,there are some shortcomings such as overlapping data information,easy falling into local minima,complex structure of the model,poor generalization ability and slow learning efficiency.To this end,this paper presents a MBR flux prediction model based on principal component analysis(PCA)and particle swarm limit learning machine.PCA was used to reduce the dimension of the relevant factors that affect the membrane flux,extract the characteristic information,eliminate the vector correlation,and send it into the particle swarm extreme learning machine prediction model.The model makes full use of the input weights and thresholds of particle swarm optimization PSO ELM to improve the prediction accuracy and prediction efficiency of the ELM model.The effectiveness of the model is verified by field examples.Membrane bioreactor is more and more widely used in water treatment due to its advantages of small floor area,good effluent quality and low residual sludge.However,the easy membrane pollution and high energy consumption are the key factors restricting the development of MBR.Based on the CFD technology,the membrane bioreactor(MBR)was used as a research object to carry out simulation and optimization of CFD characteristics.The flow field in the aeration tank and the distribution of local gas holdup are analyzed and calculated to study the hydraulic parameters of MBR and membrane fouling as well as energy consumption so as to provide the basis for the optimal design of MBR and to prevent membrane fouling and operational parameters Make effective research on decision-making,and provide scientific basis and technical support for the development of low-cost and high-efficiency MBR.