Research On The Actual Domestic Wastewater With Low C/N Ratio By The Two-point Influent Double Mud Method OAO Process

The actual domestic wastewater was used in the test, and the two point-influent double mud method OAO wastewater treatment system was studied, the differences of the water pollutants treatment effect between the winter and contrasted was contrasted. The digestive juice reflux ratio 、the ratio of the water、the total HRT 、volume ratio and temperature impacting on the treatment effect was studied.When the digestive juice reflux ratio is 1,the ratio of the water is 2,the total HRT is 9.6h, the volume ratio is O:A:O=15:10:18,the temperature is 26℃ the treatment system is better.The digestive juice reflux ratio 、the ratio of the water、the total HRT 、volume ratio and temperature all have effects in the treatment.The temperature of the actual wastewater was different in autumn and winter, the pollutants were more in winter than in autumn. With the same methods for the sludge acclimation, the temperature was higher in autumn and the microbial activity was better than in winter, so the effect was better. With different temperature during the acclimation, the demand of effluent COD was less than 50mg/L after treatment, and the effluent ammonia kept stably less than 5mg/L in autumn, High volume load rate,low carbon and nitrogen ratio and the influent ammonia concentration was higher in winter than in autumn, which was resulted the high ammonia in winter. Due to the lackness of carbon, the total nitrogen and total phosphorus removal could not be further improved of different water temperature.The removal rates of COD and TP have less change in the different temperature of winter,but to TN and ammonia nitrogen the change is big.The removal rate of TN is 39.2% under temperature of 26℃while the removal rate of TN is22.6% under temperature of 7 ℃;The removal rate of ammonia nitrogen is 37.31% under temperature of 26℃while the removal rate of ammonia nitrogen is 5.24% under temperature of 7℃.