Biological Treatment Study Of Aquatic Products Wastewater Based On Different Standards

The State Council promulgated the Water Pollution Control Action Plan in 2015 which is a guideline for the national water pollution prevention.It indicates that China should rectificate ten key industries,including food manufacturing,which means that the standard of aquatic products wastewater emission control is becoming more and more strict.In order to providing a technically feasible and economically reasonable reference for existing enterprise technological transformation and new enterprise construction,this paper focus on three kinds of wastewater treatment such as hydrolytic acidification-activated sludge process,anaerobic-biological contact oxidation process,A²/O process,which were carried out by lab-scale experiments,and explore the removal rate of CODCr,NH₃-N,TN,TP and analyze the economic feasibility.The main results are as follows:Firstly,we found that the wastewater which were treated by these three methods can meet the Wastewater quality standards for discharge to municipal sewers.The hydrolytic acidification-activated sludge process had been operated continuously and steadily for 20 days under a better operating condition?IR is 300%,HRT is 18 h,DO is 4.0 mg/L?.The results showed that the removal rate of CODCr,NH₃-N,TN and TP were 86.5%,77%,74%,70%.If the existing enterprises directly take pollutants away from the plant into the river,it is necessary for those enterprises to take some precautions such as fill with carriers for the survival of microbes or modify the hydrolysis acidification pool as an anaerobic tank,which improve the reaction efficiency thus the process of wastewater capacity and wastewater quality.Secondly,the paper finished the anaerobic-biological contact oxidation process through orthogonal experimental design,and found a best operating condition?HRT is 21 h,IR is 300%,DO is 4.0 mg/L?.The results show that the water can meet the indirect emission standard of the basic reference Standard,but the TP removal efficiency is not good.The enterprises can add coagulant chemical ways so that improve the efficiency of phosphorus removal.And 1.0g cationic polyacrylamide?CPAM?and 50 g polyaluminium chloride?PAC??or 30 g polymeric ferric sulfate?PFS??been added into every cubic sewage,then the effluent quafity of biological contact oxidation process will meet the standards of newly-built enterprise effluent standards.The cost of the chemicals added is 0.125 yuan per ton or 0.085 yuan per ton.Then the enterprise's total adding cost is 0.3 yuan per ton wuich take the wastewater treatment plant in Yantai green food co.LTD as example.The system has stable operation,low cost,low maintenance cost and good effluent quality which can be used for the existing enterprise at a higher economic feasibility.Finally,A²/O process had been operated continuously and steadily under a better operating condition?IR is 200%,r is 200%,sludge age is 15d?.The results show that the removal rate of CODCr,NH₃-N,TN and TP were 93.6%,95%,85.3%,89% and the water can almost meet the direct emission standard which new enterprise should meet.And the operational fee is 0.8 Yuan per ton.The treatment technology is economic and effective with stable effluent quality,good resistance to shock-loading and low running cost with high outlet water quality.Neither more-developed urban areas where that city sewage and wastewater treatment plants ubiquitous nor the poorer countryside,A²/O process is proved to be rational and feasible both economically and technically.