Study on the capability of flocculants composed of waste residue and its application in treating papermaking wastewater

Inorganic polymer flocculant is an efficient reagent in wastewater treatment. With the development of modem iron and steel industry, the amount of the slag will be increased. Developing of technologies of using the element in the slag is urgent. In this paper, the characteristics of the inorganic polymer flocculants prepared from the steel and pyrite slag were evaluated. Effective groups, such as AI-OH, Fe-OH, H-OH, Al-O-Si, O-Si-O and Si-O-Fe, were found in the polymeric silicate aluminum ferric inorganic flocculants. Fe-a, Fe-b and Fe-c were all found in the polymer, and the amount of Feb is proportional to the ratio of the OH and Fe in the polymer. It is suggested that OH/Fe is a good indicator to evaluate the flocculation performance of the polymer. The efficiency in removing COD of papermaking wastewater was studied by using the flocculant. The results showed that the efficiency of the flocculation of inorganic polymer made from the steel and pyrite slag are better than that in the market.