What is a common method used for nutrient recovery in wastewater treatment?

Biological nutrient removal is an essential process in wastewater treatment that focuses on the extraction and recovery of nutrients, particularly nitrogen and phosphorus, from wastewater. This method utilizes specific microorganisms that are capable of assimilating these nutrients during the treatment process.

In biological nutrient removal, bacteria are used to convert ammonia into nitrogen gas, which can then be released into the atmosphere, thereby removing excess nitrogen from the water. Similarly, phosphorus is taken up by bacteria and subsequently precipitated or stored in the form of biomass. This not only helps in reducing nutrient loads that could potentially lead to eutrophication in receiving water bodies but also allows for the recovery of these nutrients in a way that they can be reused as fertilizers or in other applications.

This method is considered sustainable because it aligns with environmental practices aimed at reducing the environmental impact of wastewater discharges while also contributing to resource recovery. In contrast, other choices focus more on disposal methods or do not address the recovery aspect as effectively.