An industrial wastewater is high loaded with FAS, a nitrogen and sulfur-containing organic substance, which decomposes to a variety of partially toxic organic products.
A process for the treatment of the wastewater is being developed, which should be mainly a biological treatment. Therefore an analytical procedure on the basis of HPLC and spectrophotometry is optimized which provides qualitative and quantitative information about the wastewater composition. The low biodegradability of the organic contaminants is significantly increased by an oxidative pretreatment.
The original concept for the biological treatment was a two-step approach. In an first aerobic reactor, the organic carbon should be converted into CO2 and biomass and the nitrogen, which is released as NH4+. This should be nitrified by bacteria to NO3-. This was to be denitrified to N2 in a second, anaerobic reactor.
Due to a high nitrification inhibition by wastewater components, it was necessary to change this concept. Now, the first, aerobic reactor is kept under high pH and the released NH3 is stripped by intensiv aeration. The NH3 is planned to be nitrified aerobically in a separate trickling filter. The resulting NO3- will be treated anaerobically to give N2 in a third reactor.
The scale up from laboratory to pilot scale and possible industrial application will be the last part of the project.