What are the methods of removing oils and grease from wastewater in water treatment plants?
1. Dissolved Air Flotation (DAF):
This is a physical/chemical process that uses air bubbles to separate oil and grease from wastewater. The air bubbles attach to the oil and grease, causing them to float to the surface of the water where they can be skimmed off. The impact of this method on treatment is that it can reduce the amount of oil and grease in wastewater by up to 90%.
2. Chemical Coagulation:
This process involves adding chemicals such as alum or ferric chloride to wastewater, which causes suspended particles and oils and grease to form larger particles that can be more easily removed by filtration or settling. The impact of this method on treatment is that it can reduce the amount of oil and grease in wastewater by up to 80%.
3. Oil/Water Separators:
These are tanks that are designed specifically for separating oil from water. They work by allowing the lighter oil molecules to rise to the top while heavier water molecules sink to the bottom, where they can be removed separately. The impact of this method on treatment is that it can reduce the amount of oil and grease in wastewater by up to 95%.
