Study On The Producing Of Ferric-polysilicate Coagulant & Treatment Of Paper-making Wastewater

Ferric-polysilicate coagulant is a new type of inorganic polymer flocculants; it's made up by adding ferric to polysilicate-sulfate, and it has not only the property of electricity neutralization of iron, but also the property of adsorption and framing of polysilicate-sulfate. It is more efficient than traditional flocculants in depurating wastewater.The procedure of producing, Fe/Si ratio (molar ratio) and hydrolysable grade B* all have an effect on the properties of Ferric-polysilicate coagulant, When Fe/Si molar ratio equals 5:1, and B* equals 0.5, the Ferric-polysilicate coagulant performs the best.In the process of paper-making wastewater treatment by flocculating, stirring rate and time, pH value, temperature and quantities of flocculation all influent the result of flocculating . At the optimum condition , CODCr of paper-making wastewater can be reduced to about 250mg/L from 1650mg/L, and tone reduced to 2 times from 250 times, it conforms to the first rate standard of discharging. By contrast experiment we can know that the applicable scope of PFSS is wider. Temperature effect lower and quantities of PFSS needed less.Under the same experiment conditions, flocculation settling velocity constant of Ferric-polysilicate coagulant amounts to 4.98mm/min, is as 3.41 times as the PAC's. According to the flocculent precipitating curve at various temperatures, the influence of temperature on flocculating and the m are talked about by via of traditional dynamics, by analyzing the results , we can see that the m all is over 15 K T. Concluding from DLVO theory then it is certain that the colloid particle is steady.