Research On Treatment And Reuse Of Western Hubei High Phosphorus Hematite Reverse Flotation Wastewater

Western Hubei is not only an important ecological function region, but also rich in mineral resources.Mineral resources exploitation in this region, must be no pollution or less pollution, otherwise it will cause serious ecological disaster.In this paper, using reverse flotation wastewater of high phosphorus hematite from Weatern Hubei as study object, water quality was comprehensively analysis and the results showed that:the flotation wastewater is of high alkalinity and turbidity. The main pollutant is SS, CODCr and TP, by comparing the CODCr & TP of raw wastewater and its filtrate, it was found that if suspended solids in water can be removerd, CODCr and TP may also be removed accordingly. XRD and particle size distribution analysis showed that the major components of suspended matter are Fe2O3, and average particle size of suspended solids is about 120.3nm. Under the condition of raw wastewater pH value, the zeta-potential of suspended particles is-31.63mv, which results in colloidal stability property of suspended particles. And calculation results by Stoks gravity sedimentation formula indicated that the water can not be natural sedimentation to remove suspended solids.On the base of comprehensive analysis of water quality and suspended solids property, a coagulation/flocculation-precipitation treatment process was proposed. A number of inorganic coagulants/flocculants, including lime, aluminum and ferric coagulants/flocculants, combined with PAM were used and the best operating parameters were determined through experiments. Under the best conditions, the effluent is of turbidity<1NTU, TP<0.5mg/L, CODCr<100mg/L. ICP-AES test results show that the residual concentrations in effluent of the main components of coagulants/flocculants are:Ca2+53.04mg/L (CaO), SO42-188.34mg/L(Al2(SO4)3), Al3+<0.25mg/L(aluminum flocculants), Fe3+<0.06mg/L(ferric flocculants). Cost accouting show that the treatment costs of all the coagulation-precipitation programs are lower than 0.5yuan/m3, except AlCl3+PAM program.Sveral materials with neagative impact on recovery and grade were determined by results of ICP-AES test on filtrate of raw wastewater and coagulation effluent and previous research. These materials are:Ca2+, Mg2+, Al3+, Fe3+, Mn2+, SO2-and sodium oleate, starch and PAM. Using solution containing each of those materials as flotation water and taking a 1% fall in concentrate grade as as the judging criterion, upper limit concentrations of each substance mentioned above are determined; Coagulation effluent flotation results show that, comparing with fresh water flotation, concentrate grade of FeCl3+ PAM effluent flotation increase appreciably and grade is almost constant.of water and water for flotation flotation index compared to slightly concentrate grade increase the recovery rate is almost constant. Taking cost and impact on recovery and grade as judging criterion, the best wastewater treatment program is FeCl3+ PAM, and corresponding wastewater treatment and reuse procedure was proposed.Finally, it can be concleded that FeCl3+ PAM coagulation-precipitatioin program, whose effluent can be totally reused, is a low-cost and available technology with remarkable economy and environment benegfits.