Research And Implementation On Optimal Control Of Wastewater Treatment Oxidation Ditch Process Based On Improved PSO

The wastewater treatment is one of the most important parts of the environment protection. Effective treatment of wastewater can improve water quality of rivers and improve the natural ecology. Nowadays, activated sludge wastewater treatment with oxidation ditch is one of the world’s popular wastewater treatment methods. The process of organic matter decomposed by microorganisms in activated sluge can effectively reduce pollutants. However, the wastewater treatment process consumes a lot of energey. The energy efficiency of the wastewater treatment process in China has a big gap compared with developed countries, and energy consumption of per ton of water is about twice as many developed countries. It brings tremendous burden for governme finances that wastewater treatment costs are too high, and it leads to part of the sewage is directly discharge without treatment, causing serious pollution of surface water. Under the premise that guaranteeing the quality of the output water, effectively reducing the energy consumption of wastewater treatment is the main research content of this thesis.Based on the dissolved oxygen concentration and sludge concentration as control variables, genetic algorithm and particle swarm optimization algorithm was applied to solve the best settings of the dissolved oxygen concentration and sludge concentration in this thesis. When the dissolved oxygen concentration and sludge concentration is equal to the best settings, the process of wastewater treatment has low energy consumption and water quality reach the standards.The thesis compares the performance of solutions with genetic algorithm and particle swarm optimization algorithm, improving the traditional particle swarm optimization algorithm, reducing the chance that the algorithm falls into local optimal solution.In this thesis, wastewater treatment solution based on improved particle swarm optimization algorithm successfully applied in Huangshan city wastewater water treatment plant, effectively saving energy.The solution designed by the thesis can be applied to other wastewater treatment plant with oxidation ditch, using activated sluge method; it has a certain promotional value.