Study on domestic sewage treatment by iron-carbon filler-coupled biofilm method

Abstract: Different kinds of iron-carbon micro-electrolytic fillers were prepared by sintering at high temperature of 700~1 000℃. Static experiments showed that the iron-carbon micro-electrolytic fillers mixed with aluminum powder had significant treatment effect. NH4 + -N, COD and TN reached 6.18%, 44.18% and 6.86% respectively, and the removal effect was better than other fillers. The removal rate of iron-carbon filler doped with aluminum powder is 33.45% of TP, which is lower than the removal rate of 35.53% of iron-carbon microelectrolytic filler doped with magnesium carbonate. However, according to the comprehensive treatment effect, the best filler for treating domestic sewage is the iron-carbon micro-electrolytic filler mixed with aluminum powder. The iron-carbon microelectrolytic filler mixed with aluminum powder was added into the successful biofilm reactor, and the results showed that the average effluent removal rate of the biofilm fed with iron-carbon microelectrolytic packing in NH4 + -N, COD, TN and TP reached 85%, 89%, 79% and 81%, respectively. According to the current situation and characteristics of rural domestic sewage in China, based on the high efficiency and simple application of rural domestic sewage treatment, an iron and carbon micro-electrolytic coupling biofilm treatment device is designed and prepared, and the operation effect is studied. The results show that the iron-carbon microelectrolysis technology uses the potential difference of the iron-carbon filler itself in the wastewater to degrade the organic matter. At the same time, iron-carbon microelectrolysis technology also has a certain effect in improving the biochemical properties of domestic sewage, phosphorus removal and auxiliary biological nitrogen removal. In this study, iron-carbon microelectrolytic filler was prepared by high temperature sintering, and the domestic sewage was treated by biofilm. The results show that the iron-carbon microelectrolytic fillers mixed with aluminum powder are compared with other microelectrolytic fillers. By starting the iron-carbon microelectrocoupling biofilm hanging experiment of the biofilm device, when the biofilm device operates stably, the removal of the biofilm device. The removal mechanism of COD and total phosphorus from domestic sewage by iron-carbon filler fits a quasi-second-order kinetic model. The experimental device of this study has the advantages of high efficiency of biofilm, small amount of residual sludge and simple operation, and the added iron carbon filler can strengthen its treatment effect on domestic sewage, improve the removal effect and removal stability of effluent.