IMBR - Advance Sewage Treatment Plant

Package Sewage Treatment Units
For up to 1,000pe

Naston Immersed Membrane Biological Reactor (IMBR) packages offer a robust, secure process, that guarantees very high quality effluent whilst reducing sludge disposal and maintenance costs when compared to conventional activated sludge processes using tertiary treatment.

MBR Process Benefits

- Effluent quality to 5mg/l BOD, 5mg/l TSS, 2mg/l NH4-N
- Nitrogen removal
- Disinfected effluent
- Very low sludge production
- Membrane separation guarantees environmental protection

A range of technical and commercial advances borne out of over 25 years of Naston wastewater treatment experience worldwide:

IMBR features
- Simple reliable operation
- Security and flexibility
- Odour and nuisance free
- Easy installation and small footprint
- Low maintenance
- Minimal operator attendance
- Naston warranty

Typical Applications
- First time treatment - domestic or industrial
- Side stream or temporary capacity
- Sensitive or restricted locations
- Mild Steel or stainless units
- Disinfected IMBR effluent ideal for re-use
- Standard units available: NM1 (250pe), NM2 (500pe), NM3 (750pe)

The Naston IMBR Plant shown is the 500 p.e. unit, which is incorporated into a steel tank.
This unit provides an operation module housing the automated control system and blowers and a treatment tank containing the membrane packs.
A membrane lifting frame is included for ease of removal and to prevent the need for tank drain down.

The IMBR Process

The IMBR process combines the principles of activated sludge treatment and membrane filtration to deliver a very high quality final effluent, whilst requiring a much smaller footprint than conventional systems. In contrast to conventional activated sludge, there is now reliance on the settleability of biomass flocs, as membrane filtration uses a physical barrier to separate solids from treated effluent resulting in a disinfected effluent.

The quality and reliability of effluent is much higher, enabling re-use of effluent with no further treatment. In addtion, higher mixed liquor concentrations reduce the required plant volume, permitting smaller plant footprint and lower construction costs.

Air is fed in below the membranes to supply oxygen for biological growth and air for membrane scouring. A sludge recycle pump returns mixed liquor to a selector zone, where it is mixed with the raw sewage to promote a healthy mix of biomass species. The filtration process permits continual transfer of effluent out of the plant, under a hydrostatic head. The 0.1mm pore size prevents the biomass from passing through, whilst their uniform pore shape helps reduce clogging.

Membrane Packs
The membrane elements are manufactured from PVDF (poly vinylidene fluoride), which offers extremely good chemical resistance and protection from physical damage. PVDF produces a filtration surface with a very high pre density and small pore size resulting in high flux combined with a low potential for fouling.

The membrane permeate can be removed either by gravity or pumped suction depending on site conditions.

Low maintenance
Naston IMBR packages have the benefit of durable stainless steel or epoxy coated mild steel construction, with reliable and robust pump and air blowers which reduce maintenance. The membranes normally require twice yearly chemical cleaning to remove any solid build-up.

Naston Guarantee
Naston Ltd will warrant the process performance and quality of the plant and equipment supplied.