Hydrolytic Acilification+aeobic Contact Oxidation Treatnent Of Cider Wastewater

High concentration cider wastewater is discharged with high pollutants content, SS, and low pH value, and the quality and flow of this water varies greatly. Pollutions from cider wastewater have been increasing in current time. Biological treatment of cider wastewater was studied in this paper; meanwhile, this paper mainly researched the treatment of cider wastewater of shann' xi province, providing a better reference and application value for similar waters.Hydrolytic acidification+aerobic contact oxidation process was used to treat the wastewater. Purpose of this process was to study high concentration cider wastewater system, to analyze COD, BOD, pH and SS so as to obtain the optimal design control parameters.The results showed that use of this process to treat the high concentration cider wastewater was valid. When the system was stable running, COD concentration of inflow changed greatly, the highest was 6530mg/L, and the lowest was 2600 mg/L, 5729 mg/L averaged in the inflow. And SS concentration varied between 2877mg/L～2261mg/L, the average value was 2467 mg/L. The COD concentration of outflow stayed between 133 mg/L～355mg/L, 251.4mg/L averaged in the outflow, and the average removal rate was 95.56%. SS concentration of the outflow came between 362 mg/L～269mg/L, the average value was 322mg/L, and the average removal rate was 86.9%. A stable quality of outflow was reached under variable wastewater quality and increased quantity of wastewater of inflow, which showed that the system exhibited a good shock load resistance capability and good stability.Coagulation test was used in the treatment system, and the results showed that adding of PAC and PAM as coagulant and flocculant, respectively, obtained a worse coagulation effects and the highest COD removal rate was only 18.3% with a high COD outflow. COD of cider wastewater was mainly present in the form of dissolubility and colloid and such kind of wastewater should be treated with biological treatment. Therefore, coagulation test was not recommended here, biological treatment was introduced to treat such kind of wastewater. The first contact oxidation reactor and hydrolytic acidification reactor played an important role in removing COD; the total removal rate of 87% was achieved in the two above reactors. The second contact oxidation reactor contributed a relative little COD removal rate of 13% to the total removal rate.The results showed that in using hydrolytic acidification +contact oxidation process to treat the cider wastewater, the optimum volumetric loading of the hydrolytic acidification reactor and the contact oxidation reactor was 10.1kgCOD/m~3·d and 6.1kgCOD/m~3·d, respectively.