Study On Upgrading And Reconstruction Program Of Sewage Treatment Project For A Chinese Medicine Enterprise In Shaanxi

A Chinese medicine enterprise in Shaanxi is located in the east of Shanyang County of Shangluo City with 7.3 hm²,which is set up for the main production of chinese patent medicine.The design scale of sewage treatment system for the production base is 300 m3/d,and the treatment process is applied as following“adjustment+hydrolysis acidification+contact oxidation+sedimentation+clean water tank”.The actual capacity of daily processing is up to 1100 m3/d,which has been found to overload.Furthermore,according to the enterprise development planning,the scale of production of the production base is planning to expand to about 81 ha,and the wastewater quantity after the expansion is anticipated to 1500 m3/d.With the development of enterprises and the expansion of production scale,the original treatment technology and corresponding facilities can be no longer guarantee the water quality of the treated water up to the emission standard.Therefore,upgrading of the original sewage treatment system should be carried out so as to meet the discharge requirements of sewage and the development needs of enterprises.According to the company’s wastewater source,combining the results of survey sampling analysis and relevant studies,the quality indexes of the influent was determinedasfollowing“COD_cr=2500mg/L,BOD₅=1000mg/L,SS=430mg/L,TN=150mg/L,TP=2mg/L”.On the basis of the characteristics of sewage water quality,biodegradability,emission rules and discharge requirements,the sewage treatment process of this project was improved as“adjustment-hydrolysis-two stage A/O-two sedimentation tank-discharge”.After treatment,the water quality of the effluent should meet the requirements of《Discharge standard of water pollutants for pharmaceutical industry Chinese traditional medicinecategory》（gb21906-2008）and《Wastewater quality standards for discharge to municipal sewers》（CJ343-2010）.In this study,the wastewater treatment system was designed based on the characteristics of water quality and water quality,and the determination of the parameters for each process unit,the horizontal and vertical layout and the supporting public works were accomplished.In addition,cost analysis and construction organization programming were also conducted.The result was indicated that the project technology was simple and practical with lower operation and maintenance cost.Furthermore,the operation cost of wastewater treatment was estimated to 1.91 yuan/m³,which can effectively reduce construction investment and operation cost and meet the medium-term and long-term wastewater treatment and discharge requirements of the shaanxi bi kang pharmaceutical group production base.