Flotation is a popular and effective option for a water treatment plant installation. This is one of the most impressive techniques, especially for waste waters that are high in solids and/or fats, oils and greases.
Any contaminants that are buoyant have a great tendency to float naturally.
Mechanically assisted flotation involves micro-bubbles or white water – these bubbles rush to the surface, assisting in the speed of flotation – this is known as Dissolved Air Flotation (DAF).
Again, there is the option of a chemically assisted technique – this involves coagulation and flocculation of smaller particles to make larger particles that can trap air beneath them, greatly assisting the flotation process.
Advantages of DAF:
- Can offer solids removal rates of over 95%
- Only two moving parts – the aeration pump and scraper
- Discharge under gravity
- Minimal maintenance
- Common sense dictates it cannot fail to offer some solids removal when operating correctly
- Physically strong – steel construction, durable, long lasting
- Average cost
- No requirement for mains water or air compressor, the aeration pump takes in atmospheric air
- Includes conical base for removal of settleable solids
- Particle size is of no significance compared to the micro bubbles which are less than 10 microns in diameter