Treatment of Wastewater with High Ammonium Nitrogen Concentration

The paper deals with the problem of wastewater treatment with specific physicochemical composition (increased ammonium nitrogen concentration) which were generated in Motor Rest Areas (MRA). Conventional biological wastewater treatment systems with activated sludge were used to purify the wastewater from sanitary equipment used in MRA. On the basis of the research conducted on four MRA, an attempt was made to determine the impact of the wastewater quality on biological wastewater treatment processes. The wastewater supplied to the treatment system was characterized by predominance of biologically non-degradable organic matter (average BOD/ COD ratio 4.39 – 10.42) as well as high concentration of ammonium nitrogen 273.9 – 334.55 mgN-NH4/dm3. The wastewater alkalinity determined by high content of ammonium nitrogen had a negative impact on the biological treatment processes. Unequal pollution load and temporary, high hydraulic load caused leaching of solid suspension from settling tank as well as leaching of particles of activated sludge from the reactor’s chamber. The lack of organic matter susceptible to biological decomposition makes it difficult to develop the biocenosis of activated sludge, and the limits of ammonium nitrogen concentration inhibit the nitrification processes.