Of Baf + Anaerobic Sludge Combined Process Of Coking Wastewater Denitrification

At present, actived sludge takes an dominant part in the dealing with the coke-plant wastewater .but along with the exploitation of new type filling , technology of biofilm is developing rapidly.In this paper we use conbined BAF and anaerobic sludge system to deal with the coke-plant wastewater.we research the capability of bio-denification from aeration flow , temperature, pH, concentration of NH3-N and so on.We use PYC as the filling to hang Biomembrance.In this process,we maintain the aeration flow in 0.20L/min and the temperature in 25°C.We find that the PYC filling is easy to hang Biomembrance.After using notrifier sludge to aerate 5d and running 10d,hanging biomembrance is successful.After using coke-plant wastewater to domesticate 13 d,the removal of NH3-N in coke-plant wastewater maintain above 98%.In the beginning of the hanging biomembrance and domestication,we find obvious NO2" accumulation.But the predominance of NO2- is weakening with the time.In the research, we find that the BAF has high nitrified rate in the aeration flow above 0.25L/min and the temperature from 20℃ to 35℃ and pH from 6.0 to 9.0.Back wash takes an most importance part in the NO2- accumulation. Connecting with the NO2-accumulation and nitrified effluent , the run parameter is that the aeration flow is0.25L/min and T=20℃ and pH=8.0 and HRT<7.4h and the back wash cycle is 23h. At the same time, we find the shortcut nitrification-denitrification and the highest removal rate of TN is 45.78%. It's affected by back wash.Researching on the anaerobic sludge, the denitrified rate changes little with the pH from 6.5 to 9.0.The NOX--N in the outlet water under 2mg/L in the condition with MLSS-5000mg/l and C/N>4 and T=30℃ and pH=8.0 and HRT<2h.