Modeling a Two-Stage Trickling Filter Wastewater Treatment Plant to Simulate the Fate of Dissolved Organic Nitrogen and Its Biodegradability

The biodegradability of effluent dissolved organic nitrogen (DON) is important becausebiodegradable DON (BDON) can support algal growth and/or consume dissolved oxygen as it is further degraded. Removal of BDON through biological treatment processes can contribute to effluent DON reduction. The fate of DON and BDON through a wastewater treatment plant with a two-stage trickling filter treatment plant was modeled. The BioWin v3.1 model was successfully applied to simulate NH3, NO2, NO3, total dissolved nitrogen, DON and BDON concentrations through a two-stage trickling filter plant. Maximum growth rates (μmax) for ammonia oxidizing bacteria (AOB) and nitrite oxidizing bacteria (NOB), and AOB half saturation constant influenced ammonia and nitrate output results. Hydrolysis and ammonification rates influenced all of the nitrogen species in the model output, including BDON.