Common MBBR problems and potential solutions

Moving Bed Biofilm Reactors (MBBRs) are widely used in wastewater treatment plants due to their high efficiency and low operating costs. However, like any other technology, MBBRs are not immune to problems. In this article, we will discuss some of the common MBBR problems and potential solutions.

Introduction

MBBRs are a type of biofilm reactor that uses a moving bed of plastic carriers to provide a surface for the growth of microorganisms. The microorganisms attach to the surface of the carriers and form a biofilm that breaks down the organic matter in wastewater. MBBRs are known for their high efficiency, low operating costs, and ease of operation. However, they are not without their problems.

Common MBBR problems

Carrier loss

One of the most common problems with MBBRs is carrier loss. The carriers can be lost due to a variety of reasons, including hydraulic shock, excessive aeration, and mechanical failure. Carrier loss can lead to a decrease in the efficiency of the MBBR and can also cause problems downstream.

Clogging

Another common problem with MBBRs is clogging. Clogging can occur due to the accumulation of solids on the surface of the carriers or in the interstitial spaces between the carriers. Clogging can lead to a decrease in the efficiency of the MBBR and can also cause problems downstream.

Biofilm detachment

Biofilm detachment is another common problem with MBBRs. Biofilm detachment can occur due to a variety of reasons, including hydraulic shock, excessive aeration, and mechanical failure. Biofilm detachment can lead to a decrease in the efficiency of the MBBR and can also cause problems downstream.

Nutrient deficiency

Nutrient deficiency is another common problem with MBBRs. Nutrient deficiency can occur due to a variety of reasons, including insufficient influent nutrient levels, insufficient aeration, and insufficient mixing. Nutrient deficiency can lead to a decrease in the efficiency of the MBBR and can also cause problems downstream.

Potential solutions

Carrier retention

To prevent carrier loss, it is important to ensure that the MBBR is designed and operated correctly. This includes ensuring that the hydraulic loading rate is within the recommended range, that the aeration rate is not excessive, and that the mechanical components are functioning properly. Additionally, it may be necessary to install screens or sieves to prevent the carriers from escaping.

Cleaning

To prevent clogging, it is important to ensure that the MBBR is cleaned regularly. This can be done by backwashing the MBBR or by using chemicals to dissolve the accumulated solids. Additionally, it may be necessary to install screens or sieves to prevent solids from entering the MBBR.

Biofilm management

To prevent biofilm detachment, it is important to ensure that the MBBR is designed and operated correctly. This includes ensuring that the hydraulic loading rate is within the recommended range, that the aeration rate is not excessive, and that the mechanical components are functioning properly. Additionally, it may be necessary to install screens or sieves to prevent hydraulic shock.

Nutrient supplementation

To prevent nutrient deficiency, it is important to ensure that the influent nutrient levels are sufficient. This can be done by adding nutrients to the influent or by using a nutrient-rich influent. Additionally, it may be necessary to increase the aeration rate or the mixing rate to ensure that the microorganisms have access to the nutrients.

Conclusion

MBBRs are a popular choice for wastewater treatment due to their high efficiency, low operating costs, and ease of operation. However, they are not without their problems. Carrier loss, clogging, biofilm detachment, and nutrient deficiency are all common problems with MBBRs. To prevent these problems, it is important to ensure that the MBBR is designed and operated correctly. Additionally, it may be necessary to install screens or sieves to prevent carrier loss and solids from entering the MBBR.