The Effect Of Stationary Magnetic Field On The Anaerobic Activated Sludge Performance

At Present, the urban sewage treatment and resource recyeling has become an urgent need to address our country’s problems.But the conventional activated sludge process technology has some shortcomings:long water residence time, low processing power per unit area,large area reactor,sludge bulking and so on.In recent years, with the development of science and technology and cross-technology integration application, sewage by magnetic effect degradation of pollutants, has become an emerging water processing teclmology. This theis focus on the effect of the constant magnetic field to the activated sludge process.At the same time, a constant magnetic field on the performance of the activated sludge morphology and Removal of Nitrogen and Carbon was studied in detail, in addition, Preliminary analysis of a constant magnetic field in the activated sludge biological communities metabolism were investigated; Explore the interaction of two heavy metal ions (Cu2+and Hg2+) the combination of activated sludge EPS, and at the same time a constant magnetic field of this combination provides a theoretical basis for the application of EPS in activated sludge to provide a theoretical foundation for the treatment of actual domestic wastewater.With low concentrations of synthetic domestic wastewater (influent COD concentration remained nearly at500mg/L), we investigated the influence of a constant magnetic field on the activated sludge process, as well as extracellular polymeric. During the process inoculation, when yellowish flocculent sludge gradually become yellow-brown granular sludge bacteria group, activated sludge settling velocity higher activated sludge settling velocity in a constant magnetic field. In a constant magnetic field of the activated sludge COD and NH4+-N removal rate remained stable at more than95%COD and NH4+-N concentrations were stable below20mg/L and15mg/L, which also higher than the control group of70%treatment effect. Using FISH analysis, activated sludge samples collected by different periods found in the microbial community of AOB and denitrifying bacteria biomass in a constant magnetic field condition to be higher activated sludge samples. At the same time, the determination of activated sludge extracellular polymeric show that the constant magnetic field plays a facilitating role on the secretion of proteins and polysaccharides.Meanwhile, this paper examines the binding mechanism between Cu2+and Hg2+and EPS extracted from activated sludge as well as the influnent of stationary magnetic field onto this binding mechanism. By three fluorescence spectra, we found in different concentrations of EPS concentration, the intensity of peak was significant changes, while the peak position has not changed, while the Zeta potential did not change significantly. However, under the influence of a constant magnetic field, through the three-dimensional fluorescence spectra we found, the intensity of peak as well as Zeta potential have significant changes, while the peak position has not changed. These results suggest that binding mechanism between Cu2+and Hg2+and EPS extracted from activated sludge was covalent bond, and a constant magnetic field to promote the secretion of microbial extracellular polymeric substances, making the EPS and Cu2+or Hg2+together through the combined of covalent bond and electrostatic interaction.