Study On Pretreatment Effects Of Pharmacy Wastewater By Ozone-hydrolysis Acidifying

Pharmacy wastewater by treatment of the plant disposal station called pharmacy tail water.After treatment the pharmacy tail water, still can not reach discharge standards and furtherdisposal in city sewage treatment plant. pharmacy tail water were poor biodegradability, hightoxicity, if directly discharged into the sewage treatment plant,the subsequent biochemicaltreatment were effected.Therefore in the sewage plant pharmacy tail water need pretreatment toimprove the biodegradability,. The effects of ozone oxidation-hydrolysis acidification processto pharmaceutical tail water pretreatment effect were investigated. Based on the water qualitymonitoring and analysis of pharmaceutical companies, the ozone oxidation hydrolysisacidification process parameters were optimized, the following conclusions were drawled:1. Pharmacy waste water after the factory processing, still could not achieve" Liaoning Provinceintegrated wastewater discharge standard"(DB21/1627-2008) requirements, must carry out thefollow-up processing.2. Pharmacy waste water evaluation shows that the tail water concentration, the effluent qualitywas COD≤300, BOD5≤35.3. Pharmacy tail water of refractory COD was approximately80%, including51kinds of mainorganic matter; These become the bottleneck for further processing.4. Based on the analysis of the preliminary selection of pretreatment technology, ozoneoxidation and adsorption of activated sludge process and ozone oxidation and hydrolysisacidification process were chosen.Through technical and economic comparison, the final choicewad ozone oxidation and hydrolysis process.5. Ozone oxidation unit tests showed that, along with the ozone dosage from2.5mg/L graduallyincreased to30mg/L, the removal rate of COD guarantee rate has been gradually improve. In theozone dosage of2.5mg/L, COD20%removal of guarantee rate was only34%, while in theozone dosage of30mg/L, COD21%removal of guarantee rate was78%. In addition to30mg/L, BOD5/COD ratio can reach0.19guarantee rate was77%, indicating that the ozone dosagehigh biodegradability improved fast. Therefore the optimal ozone dosage was25-30mg/L.6. Ozone oxidation-hydrolysis acidification test showed that, in addition to ozone25mg/L, hydrolytic tank retention time of8.6hour, COD removal rate was above30%. The addition of25mg/L ozone, hydrolysis time8.6hour cases, ozone oxidation and hydrolysis acidificationprocess BOD5/COD value was greater than0.25.7. Hydrolytic acidification-ozone oxidation experiments showed that the hydrolysis tank,residence time of10hours, adding ozone20mg/L, the removal rate of COD was18%-40%, andcompared with ozone oxidation-hydrolysis acidification process, it was worse effect. But thehydrolysis process on the front, the role of proteolysis is not big, basically rely on ozoneoxidation of organic matter in the water. Ultimately the best process was ozone oxidation-hydrolysis acidification process.8. Pharmacy tail water using ozone oxidation and hydrolysis process, ozone dosage is25-30mg/L, reaction time8-10h, removal rate of COD was30%, BOD5/COD ratio was larger than25%inwastewater, and wastewater quality index can reach the sewage plant follow-up biochemicalprocessing requirements.