Are The MBBR Media Environmentally Friendly?

The Moving Bed Biofilm Reactor (MBBR) process utilizes floating plastic carriers (media) in the aeration tank to increase the number of microorganisms available for treating wastewater. At the core of this process are the MBBR medi, which provide a surface area for bacteria in the aeration system to grow during the treatment process. However, as this technology is increasingly applied in various fields such as municipal sewage, domestic sewage, and chemical wastewater, a question often arises: Are MBBR media environmentally friendly? Today, AquaSust will discuss this topic with you in this article and analyze these media from multiple aspects to determine their level of environmental friendliness.

The MBBR technology combines the advantages of suspended growth and attached growth systems. In this system, the sewage is first aerated to create an aerobic environment. Subsequently, the MBBR media are introduced into the reactor. These media are mostly small cylindrical plastic carriers with a hollow structure.

Generally speaking, the specific surface area of each cubic meter of the media can reach 500 to 800 square meters. They provide a large attachment surface area for the inhabitation and reproduction of microorganisms, forming a biofilm. When the sewage flows through the reactor, the microorganisms on the biofilm will decompose various pollutants in the sewage through their metabolic activities, thus improving the water quality.

1. Reduction of Chemical Reagent Usage

The high specific surface area of MBBR media enables a large number of microorganisms to attach and reproduce, significantly increasing the efficiency of wastewater treatment more rapidly. Research shows that when treating domestic sewage, the removal rate of Chemical Oxygen Demand (COD) by the MBBR system can usually reach 80% to 90%, and the removal rate of ammonia nitrogen can exceed 90%. This high treatment efficiency means that in the subsequent treatment processes, there is no need for a large amount of chemical reagents to further purify the water quality. Chemicals can harm the environment and damage the ecosystem, including plants, animals, soil, and water sources.

2. Reduction of Sludge Production

In the wastewater treatment process, sludge treatment has always been a challenging issue. Since microorganisms grow in the form of a biofilm on the media, their metabolic processes are more stable and efficient. This can effectively reduce the amount of sludge produced, which is approximately 30% less than that of the traditional activated sludge process. Therefore, we can say that the use of MBBR media not only reduces the cost of sludge treatment equipment but also alleviates the environmental pressure caused by sludge landfilling or incineration.

3. Reduction of Carbon Emissions

Aeration is the most energy-consuming part of the wastewater treatment process. The aeration energy consumption of the MBBR system is much lower than that of the traditional activated sludge process. This is because the MBBR media remain suspended and moving in the aeration tank at all times, improving the oxygen transfer conditions. Through the turbulence of the water flow, oxygen is transferred more quickly from the gas phase to the liquid phase and utilized by the microorganisms. However, in the traditional activated sludge process, due to the lack of such an enhanced oxygen transfer mechanism, a higher aeration volume is often required to ensure the dissolved oxygen needed by the microorganisms, resulting in increased energy consumption.

 

(1) Material Sustainability
Most MBBR media are made of plastic materials such as polyethylene (PE) and polypropylene (PP). The production of these materials relies on fossil fuels, consuming a large amount of energy and generating greenhouse gases during the production process. They also degrade very slowly in the natural environment. For example, the production of one ton of plastic generates approximately 3 to 4 tons of carbon dioxide emissions.

(2) Impact on Microbial Communities
Although the microorganisms on the surface of MBBR media contribute to sewage purification, when the treated sewage is discharged into natural water bodies, the microbial communities in it may have an impact on the local ecosystem. This requires long-term monitoring data to determine.

1. New Materials and Processes Research

To address the issue of material sustainability, researchers are committed to developing new MBBR media materials. Biodegradable polymers made from renewable resources may be the solution in the future. At the same time, we can also improve the production process to reduce energy consumption and greenhouse gas emissions during production.

2. Improvement of the Recycling and Reuse System

After replacing a batch of MBBR media, the original media can be recycled. Through reprocessing, we can reduce the demand for new plastic materials and the cost of plastic landfilling. Currently, some wastewater treatment plants have started to try converting MBBR media into building materials or plastic particles.

Overall, MBBR media are relatively environmentally friendly in wastewater treatment. They can efficiently treat wastewater, reduce sludge production, and save energy and reduce consumption. However, they also have issues related to material sustainability and the impact on microbial communities. Therefore, people are working on improving their environmental friendliness by researching and developing new materials, improving processes, and establishing recycling and reuse systems.

AquaSust has been engaged in wastewater treatment for approximately 12 years and providing MBBR media that meet strict environmental standards. Whether for environmental protection requirements or reuse purposes, we can provide reliable solutions to achieve your water quality goals, with Aquasust's MBBR Media Factory.