Which chemical agents are commonly used to remove phosphorus from wastewater?

The use of Calcium, Aluminum, and Iron as chemical agents for the removal of phosphorus from wastewater is well-established in wastewater treatment processes. These metals act as coagulants, which facilitate the precipitation of phosphorus, converting it into insoluble compounds that can be easily removed from the water.

Calcium compounds, like calcium hydroxide or calcium chloride, can react with phosphates to form calcium phosphate, which precipitates out of solution. Similarly, aluminum salts, such as aluminum sulfate, can also bind with phosphate ions to form aluminum phosphate. Iron salts, like ferric chloride or ferrous sulfate, function in a comparable way, forming iron phosphate complexes that precipitate in the treatment system.

The effectiveness of these agents in reducing phosphorus concentrations is critical for preventing eutrophication in receiving water bodies, which can lead to harmful algal blooms and subsequent ecological impacts. Therefore, the inclusion of Calcium, Aluminum, and Iron in wastewater treatment processes is a common and effective strategy to manage phosphorus levels.