Phosphorus must be biologically converted to what for efficient removal?

For efficient removal, phosphorus must be biologically converted to orthophosphate. Orthophosphate is the simplest form of phosphate and is readily assimilated by microorganisms in the wastewater treatment process. During biological treatment, microorganisms such as bacteria utilize orthophosphate for their growth and reproduction, making it easier to remove phosphorus from wastewater.

The advantage of converting phosphorus to orthophosphate lies in its bioavailability; this means that it can be effectively taken up by the microbial population, facilitating the biological removal processes employed in wastewater treatment systems. In contrast, other forms of phosphorus, such as polyphosphorus or metaphosphorus, are more complex and less bioavailable, making them less efficient for microbial uptake and subsequent removal from the wastewater stream. Additionally, organic phosphates are bonded to organic matter, which can complicate their conversion and removal during treatment processes.

Thus, the conversion to orthophosphate is vital for maintaining low phosphorus levels in treated effluent, which is essential for preventing eutrophication in receiving waters.