Degradation Of High Concentration P - Nitrophenol Wastewater By Membrane Bioreactor

This paper was initially put forward and utilized to deal with difficult biodegradation organic matter containing p-nitrophenol (PNP) wastewater for the difficult degradable organic by anoxic microorganism and iron powder coupling process, three-dimensional electrode pretreatment process and membrane bio-electricity technology, the main contents of the study are as follows:Microbial populations decreased dramatically after used p-nitrophenol (PNP) as subject matter to domested, but the number of the adaptability microbial significantly increase, cellular structure and surface morphology changed significantly.This part is based on a typical refractory phenolic substances p-nitrophenol as the research object, the system explores the initial concentration of p-nitrophenol, pH, the amount of investment in iron, microbes and other factors on treatment effect of wastewater p-nitrophenol the study. Results show that on the condition of PNP initial concentration of 100 mg/L, pH 6.0 and 2 g/L iron, anoxic microorganism and iron coupling technics have good effect on the degradation of PNP, the removal rate nearly 97.98% after 400 minutes, The removal rate of coupling technics was higher for PNP than the sum of the efficiencies of the two individual processes. This suggests that the presence of iron can promote the PNP remove ability of anoxic microorganisms. With the help of gas chromatography/mass spectrometry (GC-MS), we find the degradation products were different from the two individual processes.This part presents a study of the electrochemical oxidation of p-nitrophenol (PNP) using three-dimensional electrodes, which to determine the optimum conditions of treating simulated PNP wastewater. The experiments were done in a little reactor equipped with PbO2/Ti anode and Ti cathode, the influence of the operating parameters such as initial pH, initial PNP concentration, voltage, initial FeO dosage and the distance of electrodes were investigated respectively. The results suggest that three-dimensional electrodes could remove the high concentration PNP wastewater effectively, more than 97.05% removal rate was achieved in the reactor under the optimum conditions of 1000 mg/L PNP, pH=3.20,5 V,115 min,50 mmol/L Na2SO4, 10 g/L Fe0 and the distance of electrodes was 7 cm.Membrane electr-bioreactor (MEBR) combined the membrane filtration, biological treatment with electric catalytic together, the section study on the pH value, PNP initial concentration, current intensity, iron concentration on membrane bioreactor process for the p-nitrophenol (PNP) method.The experimental results showed that the optimum condition of membrane bioreactor process for the p-nitrophenol treatment was 0.1 g/L iron powder,0.8 A and 200 mg/L.