Study On Preparation And Flocculating Mechanism Of The Poly Aluminum Ferric Silicate-Sulfate Complex Flocculant

This study, by using aluminum sulfate, ferrous sulfate, sodium silicate, sodium chlorate, oil of vitriol, sodium hydroxide as raw materials, the poly aluminum ferric silicate-sulfate(PAFSS) was prepared by copolymerization. By investigating the removing rate of turbidity, studied the flocculation efficiency influenced by the Al/Fe/Si molar rate, basicity and the slaking time of PAFSS. The physicochemical characteristics of the PAFSS were studied roundly by using all kinds of optical methods and modern chemical techniques, the macrostructure characteristics of PAFSS were studied by transmission electronic microscope. Studied the Interaction among the Polysilicate, Al(â…¢)and Fe(â…¢) by using Near-infrared Spectroscopy and X-ray diffraction. A ferron-eomplexation timed spectrophotometric method was used to classify the hydrolysis polymerization law of Al(â…¢) and Fe(â…¢).The hydrolysis polymerization process of aluminum ions and ferric ions in PAFSS solution was investigated by pH titration. Analyzed the oagulation performance of PAFSS by using it for an experimental water sample, Songhua River, Mudan River and Qianwei River. Some advantages of PAFSS were ascertained for the removal of turbidity, the chroma, CODMn, UV254 and NH3-N. Especially researched the flocculating effect of PAFSS for treatment of low temperature and low turbidity water. The water has a very low effluent Al concentration through the comparative experiments between PAFSS and other coagulants. Discussed the flocculant mechanism.At last, the economic benefit and the social benefits of PAFSS were analyzed.The results show that the Al/Fe/Si molar rate, basicity and the slaking time have certain invariable affection. Some complexing actions exist among the Polysilicate , Al(â…¢)and Fe(â…¢),and these complexing actions influent the structure appearance and the Hydrolyiic-polymerization process of PAFSS. Influence degree is decided by Al/Fe/Si molar rate and basicity. The results of the flocculation showed that PAFSS has a very high removal rates for turbidity, chroma, CODMn and UV254.At the same time,PAFSS adapts a very broad pH area and has a very low effluent Al concentration and has a very high purifying effect for low temperature and low turbidity water. The studying of coagu-flocculation...