Analysis And Reform Of A Pharmaceutical Wastewater Treatment In Xi’an

Traditional Chinese medicine wastewater possesses the characteristic of the bigdesign change of water quantity, complicated composition of pollutants, more foam,poor of biodegradation, high concentration of SS and so on, which make it belong tothe industrial waste water that difficult to dispose. At present, traditional Chinesemedicine industry produce the large amount of wastewater every year. The pollutants，contained in traditional Chinese medicine wastewater, must emerge adverse effect onthe natural water and the ecological environment, if they are discharged without anydisposition.Xi’an shiji shengkang pharmaceutical Co. LTD is the traditional Chinese medicineindustry, the original Chinese medicine wastewater treatment of which was CASS.However, with the expansion of the company, the amount of traditional Chinesemedicine wastewater increased rapidly, which resulted to CASS can’t satisfy therequirements of current situation，and the effluent above discharge standard.Focusing in the processing capacity and some inherent defects of CASS,according to the comprehensive analysis to the source and characteristics of traditionalChinese medicine wastewater, the treatment effect and problems of CASS, the mainbeyond index produced by CASS, and the relevant discharge standards, this paperproposed that using “hydrolysis acidification-two period of biological contactoxidation” to transform CASS of the company to satisfy the current disposition andensure discharge requirement.At the same time, by means of debugging the new technology and analyzing thetreatment effect, the result indicated that the traditional Chinese medicine wastewater,disposed by the new procedure, COD fall to85~120mg/L, BOD down to16~20mg/L, and their respective average removal rate was95.6%,97.1%when COD changed inthe range of2000~2500mg/L and BOD changed in the range of500~850mg/L. Theconclusion proved that COD and BOD attained to the “industrial wastewater dischargestandard of the traditional Chinese medicine industry"(GB21906-2008) requirements.In order to ensure the new technique working for a long time, this paperemphasized the operational condition and influential factors of the core structures ofnew technique-reactors of hydrolysis acidification and biological contact oxidation,and put forward some operational parameters of the main factors and other measures,such as maintaining pH about7, retaining dissolved oxygen between5~6mg/L,keeping the mixed liquor suspended solids at4.8g/L or so, and installing with gasregulators on aerated conduit in reactors of1#biological contact oxidation aeration inorder to avoid the negative effects of excessive gas.