Study Of Diketene, Acesulfame-K Wastewater Treatment Process Operation Evaluation And The Optimization Of Pretreatment Process

The Diketene,Acesulfame-K producing wastewater is charactered of the complex contaminants,the higher Organic matter,nitrogen,phosphorus concentration and the poor biodegradability.At present, the research in view of this kind of wastewater treatment process are very few in home. The micro electrolysis +Fenton oxidation as the main body pretreatment processes optimization scheme be proposed through the research aimed at the problem which exists in wastewater treatment station of a chemical plant. The best operational parameter of each process operation alone and combination be obtained by the single factor experiment and the orthogonal test,and then, the best combination process which pretreats this wastewater be given.According to the above ,the modification scheme on the original process flows for pre-treatment were raised, and then the cost for the project transformation investment and reagents expense were preliminarily estimated.The whole research include three stages.The first stage inspected the actual operational factor of each processing craft on wastewater treatment station,through analysis the pollutant removal effect of each processing unit, diagnosed the existed questiones which in the actual running . The second stage inspected the influence of iron—carbon microelectrolysis, Fenton oxidation and coagulation sedimentation's various factors to the COD elimination effect through the laboratory static testing.It has been studied what the different combination way of three craft to processing this wastewater's effect in the third stage.The results indicated that when m(Fe):m(C) was 1.5, pH was 2.5³, reaction time was 2h, micro– electrolysis average removes 45% of COD and the effluent showed COD between 449⁹81mg/L . For treatment with the Fenton reagent, when the H₂O₂( 30% ) dosage was 1.5mL/L , the mixing intensity was 300r/min and the reaction time was 40 min, the removal rate of COD raise 15%～20%. The effluent showed COD between 298⁸07mg/L. The coagulating test show that PAM could be able to make the good precipitation effect and the further removal effect to COD was not obvious when the pH was 7-8,the dosage of PAM(anion or non-ionic) was 1.5ml/L, the mixing intensity was 100r/min, the stir time was 5min.The optimizing control parameter of different combination ways were investigated through the orthogonal test on the basis of the single factor experiment.The result revealed that the best operating condition of micro electrolysis - Fenton oxidation - coagulation united process was: pH was 2.5, reaction time was120min; H₂O₂ dosage was 1.5ml/L, reaction time was 60min; the dosage of Anion PAM was 1.5ml/L. The most superior response condition of flocculant and coagulant aids combined dispensing process to raw wastewater was: PFS dosage was1.0ml/L,CPAM dosage was1.5ml/L, the mixing intensity was 100r/min, the mixing time was 5min.The dosage of H₂O₂ has the most important influence to COD,TP removal and the best response condition was: pH was 2, the H₂O₂ dosage was 2mL/L, reaction time 90min in the H₂O₂ enhanced micro-electrolysis test.Analysis the result of 15 day-long continuous running under the best parameters reach a conclusion that the microelectrolysis - Fenton reagent– coagulation united process had the best processing effect to this organic wastewater.The COD total removal more than 55%, TP removal reachs 90%, NH₃-N removal rate majority is the negative value, this is because the partial organic form of N was oxidated to NH₃-N after pretreatment in raw water. This united process stable in operation and low in modified cost, meanwhile it has created the good condition for the following biological treatment. This research may provide the theory and the actual reference for the disposal technological design of similar wastewater.