Submerged Aerobic Fixed Film Reactor (SAFF) is a cost-effective method of waste water treatment and sewage sanitation that is primarily used in residential and commercial complexes. SAFF process is attached growth type aerobic biological process which uses corrugated inert UV stabilized PVC media. Unlike other aerobic processes of suspended growth principally it provides higher mechanical surface area due to corrugation on media surface. This higher surface area helps biomass microbes for rapid digestion of biomass.
In the wastewater industry, SAFF Technology is used commonly for commercial and residential sewage sanitation / waste water treatment, particularly for small to medium range flow requirements. The air for process is supplied through mechanical aeration system arrangement which consist of blower and diffusers. The structured SAFF media arranged in reactor is fixed with bottom support arrangement.
Advantage of SAFF process
- MLSS concentration is much higher than what is normally achieved in aeration system of ASP process.
- Higher loading of BOD on the media enables to reduce the aeration tank size. SAFF requires 25-40% lesser tank volume as compared to activated sludge process.
- Cross-corrugation pattern of media ensures that air bubble travels in zigzag fashion, thus increasing the bubble travel path and thereby increasing the oxygen transfer rates.
- SAFF system takes higher shock loads without reducing the plant performance because of large quantity of MLSS available inside the reactor.
- Rate of sludge generation is normally lesser as compared to conventional system.
- Life of SAFF system is long (about 10-15 years) as inert PVC media material is used. Non pressurized system.
- This process is modification of activated sludge process which have eliminated its limitations.
- All these process produces better quality treated wastewater than conventional activated sludge process.
- Easily meets discharge norms.
- Odour problems, maintenance problems, are eliminated.
- High MLSS – Less Space required for the treatment.
- SAFF process able to achieve 95-98% BOD reduction.
Due to above advantages the SAFF process is used commonly in package systems where compactness of treatment is key factor.