| Biological treatment processes have been widely used for enhancing the removal of dissolved organic matter and nitrogen compounds from wastewater. In the United States wastewater treatment lagoons are the most common method of treatment for animal operations and rural domestic sewage. However, ammonia nitrogen is not effectively removed from the wastewater stream in these lagoons because of a lack of oxygen and a lack of surface area to encourage the growth of nitrifying bacteria.; This research explored the possibility of enhancing the performance of wastewater treatment lagoons through the addition of specially designed structures, Aerated Submerged Bio-Film (ASBF) reactors to encourage the growth of heterotrophic and autotrophic bacteria on submerged biofilm. These structures also force the direct contact of rising air bubbles with the submerged biofilm, hypothesized to increase the oxygen transfer rate into the biofilm, as well as increase the micro-climate mixing of water, nutrients, and waste products into and out of the biofilm. The pilot plant scale experiment is used to investigate the effectiveness of the ASBF structures.; Mathematical models are proposed to describe the dynamic behavior of the dissolved organic matter removal and nitrification in the ASBF and to develop design information for a full scale ASBF reactor. The mathematical models for ammonia nitrogen and dissolved organic matter removals present good results. |
