Florida Wastewater Practice Test

The removal of nitrogen and phosphorus from wastewater is classified as what type of treatment?

1. Primary treatment

2. Secondary treatment

3. Tertiary treatment

4. Advanced secondary treatment

The correct answer is: Advanced secondary treatment

The removal of nitrogen and phosphorus from wastewater is classified as advanced secondary treatment. This process goes beyond conventional secondary treatment methods, which primarily focus on the biological degradation of organic matter. Advanced secondary treatment employs additional processes that specifically target nutrient removal, particularly nitrogen and phosphorus, to prevent their discharge into the environment, where they can contribute to issues like algae blooms and eutrophication in water bodies. Advanced secondary treatment often utilizes techniques such as biological nutrient removal (BNR), where specific microbial processes are harnessed to convert nitrogenous compounds into harmless nitrogen gas or to uptake phosphorus into biomass that can be removed from the system. This level of treatment is crucial for ensuring that effluents meet strict regulatory standards for nutrient releases, thereby protecting water quality and ecosystems. Primary treatment, on the other hand, is focused on the physical removal of solids and does not address nutrient removal. Secondary treatment primarily targets the biological breakdown of organic pollutants without specifically removing nitrogen and phosphorus. While secondary treatment may improve effluent quality significantly, it may not suffice for meeting comprehensive nutrient management goals.