MBBR Plant
Moving Bed Bioreactor (MBBR)
A Moving Bed Biofilm Reactor (MBBR)
requires less space than traditional wastewater treatment systems. The technology uses polyethylene biofilm elements operating in an aerated wastewater regime. Each individual biofilm element has a high protected surface area to support the growth of heterotrophic and autotrophic bacteria. This results in a high rate biodegradation within the system, which also results in process reliability and ease of operation.
The process is self-sustaining as the biofilm attaches to the element modulates of the incoming load fluctuation. The attached growth provides a more dense microbial population per unit volume (compared to suspended growth), resulting in compactness, lower power consumption, minimal maintenance and capacity enhancement.
- Saving of space due to its compactness
- Easy to maintain
- Good for a high volume of load
- Extension and expanding are easy. This made possible by increasing the filling degree of carriers.
- Lower discharge costs
- MBBR is not affected by toxic shock
- Independent process performance because there is no return line for sludge; the MBBR eliminates the return activated sludge (RAS)
- It has high effectiveness of sludge retention time (SRT) which enhances the nitrification process
- Production of sludge is lower
- It does not need recycling of the sludge-like activated sludge system
- MBBR media is installed to retrofit existing activated sludge tanks in order to increase its capacity
It uses a combination of activated sludge process i.e. suspended growth and biofilter i.e. attached growth. It uses the entire tank volume for biomass growth by implementing the carriers for attached growth of biofilm. Movement of carriers is enabled by air bubbles through agitation.
The reactor can be in any shape and support different load depending on carrier filling. MBBR design of reactor depended on the actual wastewater characteristics and locality. The plants come either with vertical or horizontal mounted rectangular mesh sieves. The reactor can also be fitted with cylindrical bar sieves.
MBBR carriers are cylinders having a cross inside and fins outside to increase the surface area. The standard used is below 70% of carriers in an area of not more than 465m2 per m3. MBBR is used together with a septic tank or a pre-coagulation step for pre-treatment. MBBR technology can be designed with additional non-mechanical or mechanical system to enhance phosphorus and fecal coliform reduction.