Impacts on WWTP
The injected oxygen promotes heterotrophic activity in the wastewater and the biofilm, thereby oxidising a significant amount of organic matter in the wastewater, which results in reduced levels of volatile fatty acids (VFA) in the feed to a WWTP. This will significantly affect the biological nutrient removal in the WWTP, the extent of such impact depending upon the rate of oxygen dosing and the dosing location.
The addition of a readily available carbon source (for example, methanol) may be required to improve the nutrient removal performance to the same level as in the case without oxygen injection.
Further information can be obtained as follows:
Paper: Integrated modelling of sewer system and wastewater treatment plant for investigating the impacts of chemical dosing in sewers by Sharma et al. (2012)