Fenton Iron Mud Preparation Of Ferrous Sulfate And Polymeric Ferric Sulfate And Its Application Research

With increasingly serious environmental situation and the national wastewater discharge standards to the enterprise to further improve, make a lot of current wastewater treatment process has been difficult to meet the requirements for pollutant removal. Fenton oxidation technology on wastewater with toxic refractory pollutants has stronger removal effect. But the mud is still a problem, which will bring secondary pollution to water and earth if not be properly treated. Fenton iron mud was researched which is Fenton treatment after the existing sewage treatment plant of aerobic effluent in bagasse pulping of Guangxi. It research on their characteristics, and discusses it feasibility on the iron sludge preparation of seven water ferrous sulfate and recycles to Fenton system. And further research it feasibility on the Fenton iron mud preparation of polymeric ferric sulfate and treat the yeast wastewater. The following conclusions:(1) By the ICP-AES and SEM-EDS technology analysis Fenton iron mud, it found that has total iron content in more than50%in the Fenton iron mud,1.6%of them exist the form of ferrous ion, other all the form of ferric iron ions. Other metal content are relatively low. Therefore, Fenton iron mud can be iron recycling.(2) The best condition of preparation of ferrous sulfate by acid dipping reduction method with using Fenton iron mud are:H2SO4concentration is25%, the reaction time for30min, the temperature at65～75℃preparation of acid leaching liquid; With iron filings as reductant, temperature is higher than50℃, Fe3+in the acid soaking liquid concentration is lower than2mol/L best; Join the1:1ethanol can effectively shorten the crystallization time, improve product yield. Ferrous sulfate quality reached national standard GB664-93chemical reagent purity.(3) It research Fenton method treat the paper wastewater using homemade ferrous sulfate. Optimum reaction conditions are:the initial pH value of3, the additive amount of H2O2is0.6mL/L, FeSO4is10g/L, the reaction time for30min, aeration for20min. Under this condition, compare with the preparation of ferrous sulfate and buy pure ferrous sulfate, it found that the preparation of ferrous sulfate treat wastewater can has CODcr removal rate of74,9%and wastewater decolorization rate of80%. That means using Fenton iron mud preparation of ferrous sulfate can recycle in Fenton method of papermaking wastewater treatment process.(4) Research on Fenton iron mud as raw material by sodium chlorate partial oxidation preparation of liquid PFS, it optimal conditions are:FeSO410g, NaClO3105%, temperature of50～60℃, time for60min. The liquid PFS products meet the requirements of the GB14591-2006liquid PFS. Using product treated yeast wastewater, in the same amount, the effect is better than that of poly aluminum, is lower than the commercially available liquid PFS. It has large removal rate of wastewater CODcr, and small chromaticity removal effect.(5) Research on Fenton iron mud as a raw material preparation of ferrous sulfate with sodium chlorate direct oxidation process for the preparation of solid PFS it the best conditions are:FeSO4, H2SO4and NaClO3mole ratio was1.0:0.1:0.18, temperature of55～60℃, the time for90min, the curing temperature of55～60℃. The products meet the requirements of the GB14591-2006solid PFS. Infrared testing is further proved that the homemade products are PFS. Using product treated yeast wastewater, in the same amount, the effect of removal rate of wastewater CODcr is better than that of poly aluminum, is lower than the commercially available solid PFS. It has small chromaticity removal effect.