Study On The Design And Application Of Magnetic Flocculation Reactor

Coagulation process is a core environmental protection technology, which was found to be widely used in water or wastewater treatment. However, there were many shortages in its application, such as instability treatment effect, larger flocculant dosage and chemical sludge etc. So the exploiting for a high efficiency flocculation technology and how to improve flocculation process was concerned by specialists and scholars. With the development of technology and the complex utilization of interdisciplinary, magnetic was used in waste water treatment field and it had become a new water treating technology. It could be used alone or combined with other technology. It had many advantages such as low dissipation of energy, easy operation, without secondary pollution secondary pollution and low cost. So magnetic flocculation technology would have an extensive foreground in waste water treatment.Thereby, an innovatory magnetic flocculation reactor was designed based on the effect of magnetic. Five pairs of circular magnetic coils were used to constitute a large measuring range magnetic field generator by utilizing Helmholtz, and the reactor could be adjusted continuously from 1nT to 100mT. Then the magnetic field distribution in Helmholtz coil was simulated by Matlab. Results showed that it could be regarded as uniform magnetic field in the Helmholtz. The improved k-εmodel was used to simulate the wastewater velocity distribution in the reactor. Results showed that there was dead water region in the reactor, which had negative effect on flocculation. And then the reactor was optimized according to simulation result. Two folded plates were fixed in the reactor, which could optimize the detrimental effect of dead region, and the granule collision was strengthened. In the meanwhile, the parameters such as magnetic field,the dosage of flocculation and magnetic particle, pH value were investigated. On the basis of single factor analysis, the technical parameters were investigated through orthogonal experiment, based on which the Matlab software was used to present a mathematical regression model and fit the response curve and regression analysis for the removal rate of TSS and TP. Results showed that the removal rate of TSS, Turbidity, COD, TP and NH3-N was up to 98.4%,98.6%,63.9%,93.2% and 36.6% respectively under the optimum technological parameters:Magnetic field intensity=60mT, [PFSS]=4ml/L, pH=6, dosage of magnetic particle 150mg/L.Finally, runoff sewage, domestic sewage and dyeing waste water were treated by magnetic flocculation reactor based on the formerly laboratory investigation and a favorable treatment effect was acquired. A theoretical foundation was offered for the application and research of magnetic flocculation in the future.