Which chemical is commonly used as a coagulant in water treatment?

Ferric sulfate is commonly used as a coagulant in water treatment because it effectively helps to remove suspended particles and impurities from water. As a coagulant, ferric sulfate works by neutralizing the charges on the particles, which allows them to clump together, forming larger aggregates that can be more easily removed from the water during subsequent treatment processes, such as sedimentation and filtration.

This is crucial in water treatment because removing turbidity and other contaminants leads to cleaner, safer drinking water. The use of ferric sulfate is favored for its efficiency in various water conditions and its ability to produce relatively dense flocs, which settle well in sedimentation basins. Additionally, ferric sulfate’s role in increasing the removal of microorganisms makes it an important component in the purification process. This chemical is widely accepted in both municipal and industrial water treatment systems.

Chlorine, sodium hypochlorite, and calcium carbonate play different roles in water treatment; chlorine and sodium hypochlorite are typically used for disinfection, while calcium carbonate can be used to adjust pH. However, they do not serve the primary function of coagulation as ferric sulfate does.