How does aerating wastewater prior to primary clarification affect grease removal?

Aerating wastewater prior to primary clarification enhances the removal of grease due to several mechanisms that occur during the aeration process. When air is introduced into the wastewater, it promotes the formation of microbubbles which can attach to grease particles, leading to increased flotation. This flotation allows the grease to rise more efficiently to the surface, where it can be skimmed off during the primary clarification phase.

Additionally, aeration helps in breaking down and emulsifying certain types of grease, especially those that are more viscous or in larger clumps. By breaking these grease particles into smaller, more manageable sizes, they become easier to aggregate and remove.

Furthermore, aeration can facilitate the growth of bacteria and microorganisms that enhance biodegradation of organic material, including grease. This biological activity can help in the degradation of emulsified grease, making it less likely to interfere with the clarification process.

The combination of improved flotation and biological degradation makes aeration a beneficial step in grease removal prior to primary clarification.