The Pharmaceutical Wastewater's Treament Research And Engineering Application By Chlorine Dioxide Catalytic Oxidation Combined Biochemical Technology

In recent years, with the rapid development of pharmaceutical industry in China, the increasing discharge of pharmaceutical wastewater has been further worsened the natural environment. According to statistics, the total output value of pharmaceutical industry accounts for about 1.7% of the national total industrial output, while wastewater discharge accounted for 2%, which makes the pharmaceutical industry be one of the 12 key industries that need to be environmentally controlled. The organic wastewaters during the process of pharmaceutical production contribute to be the main pollution sources. Wide product varieties, complex process and wide varieties of raw materials of the pharmaceutical manufacturing make the pharmaceutical wastewater have more instable moisture content and wider varieties of organic pollutants, which, therefore, make the pharmaceutical wastewater be one of the most difficult treated wastewaters.Wastewaters from a pharmaceutical Co., LTD of Zhejiang province was chose as the study object of this document. Methods of chemical synthesis like polymerization, oxidation and nitrification were mostly employed during the production of synthetic active pharmaceutical ingredients and pharmaceutical intermediates in that company. The main products of this company are levofloxacin, periodontal tablets, oryzanol, bulk pharmaceutical chemicals of cefradine and iohexol, sterile powder of cefradine and so on.Basing on the test research and the same type of wastewater treatment experience, the study, aiming at the characteristics of target wastewaters, chose the combination of the physico-chemical treatment, hydrolysis acidification and contact oxidation as the main process for target wastewaters treatment. The actual effect of the structures of the treatment process was analyzed in the later debugging and operation. The results show that the design of the process is reasonable, which proved to be effectively pollutants removed. The aim of our research is to seek a treatment technology which could realize maximum recycling of the waste material and improve the quality of wastewater effectively. The following conclusion can be made from the test and actual effect of the process:1,Chlorine dioxide catalytic oxidation, as the process of physico-chemical treatment, could effectively reduce the concentration of contaminants, which could make the removal rate of COD be over 85%.2,Hydrolysis-acidification, as the process of biochemical pretreatment, could obviously improve the biodegradability of the wastewater and raise the B/C value of the wastewater, which is good for the normal operation of the aerobic treatment. Owing to the long designed hydraulic retention time and internal combined packing suspended in the hydrolysis pool, the anaerobic activated sludge and sewage could mix thoroughly, which could effectively change the difficultly degradable organic compound into smaller easily degradable organic compound.3,Sludge was respectively inoculated into the hydrolysis pool and oxidation ponds. After four weeks of acclimation, the biochemical system entered into steady state. COD reached a value below 100mg/L.According to the results, the designed treatment process proved to effectively treat pharmaceutical wastewaters, which could be a reference to the related research and engineering process design for treating the similar wastewater.