Study On Electron Fenton Treatment Process Of Dye Wastewater

As the development of my country’s pharmaceutical intermediate industry has entered a white-hot stage,the wastewater problems generated by the industry have gradually been exposed.The wastewater has complex components,strong specificity,high COD,and is difficult to degrade,and has biological inhibition and toxicity.For this reason,this subject is aimed at sampling the UASB influent water of a pharmaceutical intermediate wastewater treatment center of North China Pharmaceutical,and adopts the following combined process route for research and treatment:dosing coagulation+ozone/hydrogen peroxide synergistic oxidation method+A/O type SBR+ozone catalytic oxidation.Through experiments on sewage treatment by coagulation process,the best coagulation conditions are:p H=8,PAC dosage is 400 mg/L,PAC dosage and PAM dosage are 10:1,coagulation The stirring time is 15 minutes.After the sewage is coagulated,the removal rate of COD of the effluent is 38.3%.The ozone/hydrogen peroxide synergistic oxidation experiment confirmed that the best process conditions are:adjust the p H=9,the addition amount of hydrogen peroxide 8.8 g/L,dosing in three batches,the dosing ratio is 2:1:1,ozone dosing The dosage is 4.0 g/L,and the reaction time is 40 min.The COD degradation rate of ozone/hydrogen peroxide pre-oxidation effluent reached 34.6%,and the chromaticity removal reached 99.29%.The biological oxygen demand（BOD₅）of the concentrated liquid raw water and the electric Fenton effluent was tested,and the results showed that the BOD₅/COD of the ozone pre-oxidation effluent increased from 0.257 to 0.367.A 33-day ozone pre-oxidation effluent acclimation experiment was carried out on activated sludge,which improved the removal rate of COD and NH₃-N.The experiment optimized the dissolved oxygen（DO）and aeration time（At）parameters of the SBR process.The best dissolved oxygen range is 4±0.5 mg/L.The specific working conditions are stirring for 5 h,aeration for 11 h,precipitation for 1 h,in and out The water was 0.25 h each.Under these conditions,the SBR was in good condition,and the highest removal rates of COD and NH₃-N reached 82.3%and 65.0%,respectively.The effluent meets the effluent requirements of the next advanced treatment.Ozone catalytic oxidation experiment tested Mg O/activated carbon catalyst.The best experimental conditions for catalysis are:catalyst dosage is 1.2 g/L,p H=9,ozone dosage is 4.0 g/L.the COD of the effluent dropped to 84.0 mg/L,the removal rate was 84.6%,the NH3-N content was not detected,and the removal rate was 100%,which reached the national emission standard.Finally,UV-visible absorption spectroscopy was performed on the effluent from different processes to verify that the combined process can effectively improve the biodegradability of the pharmaceutical intermediate wastewater.