Experiments For Standard-attainment Discharge Of Mine Wastewater From Dexing Copper Mine Wastewater Treatment Station

Sulfide ore wastewater contain acid mine drainage (AMD) and flotation wastewater. Acid mine drainage in copper mine is characterized as low pH value and high concentrations of various metal ions, which usually emanating from mine waste rocks and tailings impoundment, etal. While flotation wastewater adapted from ore dressing workshop, and often contains amounts of residual flotation reagents, which lead to high pH and COD value in flotation effluent. Both of the water has serious damage to ecological environment if discharged directly.Mixed wastewater which formed by acid mine drainage and flotation wastewater from Dexing Copper mine industrial wastewater treatment station, characterized by low pH, high concentrations of heavy metals metal ions and residual flotation reagents. And feasibility of remove COD from the mixed water which was treated by H2O2, NaClO and O3 as oxidants was investigated in this thesis, combined with the advantages of High density system (High density system "HDS" belongs to one of lime neutra-lization systems, which was designed for treat acid mine drainage). A new system called "Fenton oxidation-calcium carbide lacteal neutralization-PAM flocculation" combined treatment process (FCPs) was developed, which decreased the COD value of effluent, and realize each water quality index of the effluent reach standard-attainment discharge.Experiments in the text were divided into two parts, lab test and half industrial experiment respectively. The lab test indicated these results.1. The reason of effluent COD cannot aatained discharge standard is HDS process remove the high concentrations of flotation reagents residue in flotation wastwater inefficiently.2. H2O2 as the oxidant is feasible and effective for the treatment of the mixed wastewater, reduce the concentration of COD.The degradation mechanism is H2O2 react with Fe2+ ions in AMD under lower pH value, produing strong oxidizing hydroxyl radicals.The results shows that the optimun H2O2 concentration is 0.5ml/L, Fe2+ ion concentration is 150mg/L, pH value is 3.50, the oxidation process conforms to a two-step kinetic model.3. NaClO and O3 oxidation exhibited poor degradation efficiency towards COD removal in the mixed wastewater. The pretreatment of flotation wastewater results shows that using O3, O3/H2O2 oxidation or coagulation treatment is difficult to reduce the concentration of COD in flotation wastewater.Half industrial experiment test results indicate:4. FCPs have better ability to treat the real mine wastewater from Dexing Copper mine industrial treatment station, this method can bearing impact load casued by wastewater quality changed effectively, the result shows that the optimal concentration of H2O2 is 0.5ml/L, the density of calcium carbide breast is 8.5g/L, PAM concentration is 1.5mg/L. The effluent quality reachingâ… -class criteria specified in Integrated Wastewater Discharge Standard (GB 8978-1996) after treatment with FCPs. The innovation of thesis is fully utilizing high concentrations of virous metal ions, such as Cu2+, Fe2+ ions in the mixed wastewater, react with H2O2 under lower pH, produing strong oxidizing hydroxyl radicals to degrade the high concentration flotation reagents in the wastewater effective, and Fenton oxidation-calcium carbide lacteal neutralization-PAM flocculation" combined treatment process as a reference technology can use for mine wastewater treatment from the mining of certain similar minerals.