1
Carriers circulate
Free-floating media is continuously mixed throughout the reactor volume by aeration or mixers.
The technology
How MBBR media works
The Moving Bed Biofilm Reactor process combines the best of suspended-growth and fixed-film treatment. Thousands of small plastic carriers are kept in continuous, gentle motion inside the aeration tank by diffused air or mechanical mixing. Bacteria colonise the protected internal surfaces of each carrier, forming a biofilm that treats the wastewater as it passes through.
2
Biofilm establishes
Bacteria colonise the protected surface area inside each carrier, sheltered from shear forces.
3
Pollutants break down
As wastewater flows past, the attached biomass metabolises BOD, COD and ammonia continuously.
Inside the tank
A protected surface for biology to work on
- MBBR carrier held in free suspension by tank hydraulics
- Diffused aeration supplies oxygen and keeps carriers in constant, gentle motion
- Bacterial biofilm grows on the protected internal surface of every carrier
- Treated effluent passes out through retention screens, media stays in the tank
Design parameters
Key process figures
Media Fill Ratio
Typically 25–70% of tank volume, sized to the design organic or ammonia load.
Retention
Slotted sieve or wedge-wire screens keep carriers inside the tank while water flows freely.
Aeration
Coarse or fine-bubble diffused air is generally used to keep carriers fully mobile.
Retrofit Scope
Media can be dosed directly into existing SBR, ASP or aeration tanks.
Performance
Why MBBR media outperforms
Because biomass lives inside a protected, high-surface-area carrier rather than in free-floating flocs, MBBR systems sustain a denser, hardier population of treatment bacteria — with a simpler process to operate.
1
High Effective Surface Area
More protected surface per cubic metre of media means a larger, denser bacterial population and faster BOD, COD and ammonia removal.
2
Compact Footprint
Higher biomass density per unit volume lets plants treat more load in the same tank — or shrink the tank for the same load.
3
Self-Cleaning Design
Constant, gentle carrier movement creates natural shear that sloughs off excess biofilm, preventing clogging without manual intervention.
4
Retrofit Friendly
Media can be added directly into existing aeration or SBR tanks to boost capacity, with minimal civil work or downtime.
5
Resilient to Shock Loads
The attached biofilm recovers faster than suspended sludge after flow surges, toxic shocks or seasonal load swings.
6
Low Operating Cost
No sludge recycle pumps to run, no media replacement cycle, and less sludge to handle — lowering day-to-day operating cost.
7
Durable HDPE / PP Build
UV-stabilised, chemically resistant polymer construction is engineered for a long service life in continuous immersion.
8
Simple Retention
Standard slotted sieve or mesh retention screens keep media inside the tank while allowing free water flow.
The result
A smaller aeration footprint, a treatment process that recovers quickly from shock loads, and an operating routine with fewer moving parts to manage day to day — all from a media upgrade that fits inside the tank you already have.
Evaluating MBBR for an existing plant?
Send us your current tank volume, flow and load figures. We'll tell you what media fill would achieve your target BOD, COD or ammonia removal.