How does MBBR technology work?

In our previous article, we talked about MBBR technology, its most important features, and the factors that must be taken into consideration when choosing this technology for wastewater treatment.

MBBR technology uses bacterial supports, called MBBR media, which are like buildings for bacteria. These “buildings” move through the water to purify it, so that the greatest number of bacteria come into contact with the greatest amount of pollution. This is summarized by the abbreviation MBBR: “Moving Bed Biofilm Reactor”

How does MBBR technology work?

Like any other water treatment technology, however, this technology can treat a much larger amount of pollution in the same volume. In fact, to treat water, 4 components are needed:

• Space for bacteria to grow
• Bacteria “eat” the pollution
• The air they breathe
• The method of transportation, and in this case it is related to movement.

To apply the activated sludge technology widely spread throughout the world:

• You should keep a large amount of water so that it has enough space for bacteria to grow (and especially so that it has time to eat the contamination)
• Bacteria are found in water where they multiply and where they are “recycled” through recirculation.
• We need to give them some air
• And they need to be shaken. For simplicity, let’s assume they are hunter-gatherer bacterial colonies.

MBBR technology works the same way:

• MBBR media acts as a building, and can accommodate a large amount of bacteria
• Bacteria colonize MBBR media, growing as biofilms. Each bacterial support is a small city of microorganisms that must be fed
• It needs to be broadcast
• It is also necessary to shake them so that these “bacterially contaminated buildings” are in good contact with the contamination to be treated.
• With MBBR technology we use the term “fluidized bed” because it is a mixture between free-living bacteria (hunters and gatherers) on the one hand, and bacteria in the form of biofilms attached to their supports (buildings) on the other hand. Which moves freely in the biological reactor.

What are the advantages of MBBR technology?

Compactness: The higher the concentration of bacteria, the smaller the overall volume of the structure. On average, MBBR technology is three times more compact than activated sludge technology.

High tolerance to load changes: Fixed cultures are more resistant in the form of biofilms, and more resistant to hydraulic and organic load shocks. When tied to their supports, they are not “washed away” during storms.

Ease of operation: MBBR technology is operated just like an activated sludge plant.

How to design MBBR basin for wastewater treatment plant?

First of all, it is important to understand the components of wastewater and the desired treatment objectives. Water temperature also affects size, the warmer the water, the more efficient the bacteria.

After that, the MBBR process is designed according to the waste parameters, water alkalinity and other criteria. The following stages can be used:

• Pre-denitrification
• Nitrification
• Denitrification
• Recycling
• Unloading
• Post-denitrification

This is very complex and each MBBR supplier knows their own bacterial support behavior and therefore has a specific sizing table for their media. You can request your quote here.

How to distinguish between MBBR technology modes?

There are several criteria included:

• Protected Surface Area of Media: The greater the protected surface area of media, the less media will need to be purchased
• Fill rate: Varies depending on the application and specific properties of the media. The filling rate affects the size of the structure. But we must not forget that there is a minimum duration of “biological” stay that must be respected. If the water flows through the reactor too quickly, the bacteria will not have enough time to clean up.
• Aeration: Bacteria need air to function, and they also need agitation. The volume of air required in an MBBR is often greater to agitate the media than is needed for biological air. This has an impact on playback balance, but fortunately, this is not the case with MBBR media.
• Compression Capacity: Some media, including ours, can be compressed, allowing for significant savings in transportation.
• Agitation: In addition to excessive aeration, some media require mechanical agitation.
• Wear resistance: Depends on MBBR media components