What method can be used to treat flow to the primary settling tank to enhance grease removal?

Pre-aeration is a technique used to enhance the removal of grease and other floating materials in wastewater treatment processes, especially before primary settling tanks. By introducing air into the influent, pre-aeration helps to break down grease and oils, making them less dense. During this process, the grease is agitated and can either be released from wastewater or made more buoyant, which allows it to rise to the surface where it can be more easily removed.

This method is particularly effective because it not only helps in separating the grease but also aids in the production of more stable flocs, if present. Coagulation and flocculation are processes that primarily aim to remove suspended solids through the formation of agglomerates, but they are not specifically designed to target grease removal like pre-aeration does. Chlorination is a disinfection process and does not contribute to grease removal, making it unsuitable for the desired outcome in this context.