Study On Optimization Of Flocculant In Coal Mine Wastewater

Coagulation is the most commonly used method to treat mine wastewater,and flocculant plays a key role.In this study flocculant was prepared by physical blending method and optimization of the preparation of the polymeric aluminum silicate iron-anionic polyacrylamide(PSAF-APAM).Application processing coal mine water removal of COD and reducing turbidity also determine the optimum process conditions of coagulation precipitation to make of COD and turbidity reaches surface water ? level standard.At present,duing to improper flocculation reagent selection and to use operation process conditions of coal mine water treatment reagent dosing,quantity is high and the problem is with poor effect.The flocculation sedimentation tank was designed according to the experimental parameters.Through single factor method analysis during the preparation of composite flocculant pH,temperature,time,poly aluminum silicate iron,and the ratio of anionic polyacrylamide various factors can find out the effect on the flocculation.With the orthogonal test,we determine the best preparation conditions of composite flocculant PSAF:APAM ratio is of 10:1,pH value is of 2,mixed time is of 1 h and the temperature is of 40?.The characterization proved that the combination of PSAF and anion polyacrylamide(APAM)integrated the advantages of the two flocculants and increased the adsorption surface area of flocculants.The addition of APAM increased the adsorption bridging,net trapping and electric neutralization of polyaluminum-iron silicate.Through the mine water treatment research to determine the PSAF-APAM composite flocculant of mine wastewater treatment using coagulation sedimentation we find that the optimal conditions are for:composite flocculant optimal dosing quantity of 60 mg/L,reduce the temperature on the flocculation effect.Without having adjusted pH value is still the best treatment effect of fast mixing-----the actual operation condensed phase are time of 2 min,the rate of 500 r/min;Slow stirring,that is,the actual operation of the vitrification stage of the time is 5 min,the rate is 120 r/min.And the standing sedimentation time is 2 h,that is,the actual running residence time is 2 h.In this condition,the composite flocculant of mine water,COD and turbidity removal efficiency of 98%and 99.34%,the residual amount of 4 mg/L respectively,1.45 NTU will up to the surface water ? level standard.Compared with coal mine raw flocculant,the efficiency was increased by 2.54%and 11.57%respectively,the input amount was reduced by 40%,and the cost per ton of water treatment was reduced by 0.07 yuan.The composite flocculant psaf-apam prepared in this study has high efficiency and economical flocculant,which has certain popularization value and research value.According to the design calculation of the flocculation-inclined plate sedimentation tank,the water amount was 12000m3/d,and the size of the flocculation tank was 3.3x3.3x 3.3m.The specification of inclined plate sedimentation tank was 16×14×5 m.