The increasing generation of wastewater from industrial plants, coupled with high concentrations of diverse pollutants, has placed significant stress on conventional wastewater treatment systems. This challenge highlights the need for advanced biological treatment processes, such as the Moving Bed Biofilm Reactor (MBBR).
The MBBR wastewater treatment process is rapidly gaining popularity due to its ability to handle high organic and nutrient loads with enhanced removal efficiency. This process is also environmentally friendly, offering a lower carbon footprint and fewer operational challenges. Its unique characteristics make it a superior alternative to traditional methods like activated sludge systems or trickling filters. MBBR stands out for its convenience, efficiency, and adaptability.
In this article, we will explore the various facets of MBBR systems, examining how they work and the numerous benefits they offer.
A moving bed biofilm reactor is a biological wastewater treatment process, i.e., it employs a biofilm to remove waste from wastewater. The microorganisms attached to media in the water consume unwanted waste, leaving clean water.
The MBBR technology was developed somewhere around the early 80s in Norway, and since then, it has been widely adopted in wastewater management techniques due to its immense benefits. It offers a safe and environmentally sustainable way to remove organic substances from wastewater. It also helps in achieving nitrification and denitrification.
Although it can work in a silo as wastewater treatment, it is mostly adopted as a regimen in the complex process of treating wastewater. It usually serves as a crucial component in a multi-step purification process, but it is neither the first nor the last way of wastewater treatment.
The MBBR systems work on the core principles of microbial degradation. As per the reactor conditions maintained, it can be aerobic, anaerobic, microbial, or facultative in nature. It is dependent on microorganisms’ activity to break down organic or inorganic compounds present in the wastewater. These microorganisms form a biofilm on the carrier media. Thus, a favourable environment is created for efficient pollutant removal.
Biofilm carriers are the core aspect of the MBBR system. The biofilm carriers could be made of any material, including plastic, PVC, or polyethylene. The surface area of the biofilm carriers is quite high to ensure microorganisms can thrive. There is a reactor tank in which these carriers are placed in constant motion, ensuring effective contact between the microorganisms and the wastewater. These carriers or media look like hexagonal wheels.
The reactor tank contains both the biofilm carriers and the wastewater. It is intended to create ideal conditions for microorganisms to thrive, such as controlled temperature and pH levels. The mobility of the carriers within the tank prevents blockage and promotes efficient treatment.
The role of the aeration system is to supply consistent oxygen to the reactor tank. Its aim is to create an aerobic environment to promote the aerobic microorganisms’ growth in the biofilm. The microorganisms have to perform multiple metabolic activities for which a proper supply of oxygen is required.
After passing through the reactor tank, the clarity unit separates the treated water from the suspended biomass (biofilm carriers and extra bacteria). The purified water is collected for further treatment or discharge, and the biomass is recirculated back into the reactor tank to sustain biological activity.
When the microorganisms present in wastewater attach themselves to the carriers, a biofilm is formed. The role of biofilm is to develop a favourable environment for microorganisms to thrive and treat the wastewater efficiently.
After the biofilm formation is complete, the organic matter present in the wastewater will act as an energy source for the microorganisms. The microorganisms will break down the complex organic compounds into simple forms, converting them into CO2 and water.
The microorganisms also help in removing nutrients like nitrogen, phosphorous, and others from wastewater. Specific strains of microorganisms inside the biofilm are critical in metabolizing and eliminating these nutrients, lowering the environmental impact of wastewater discharge.
The MBBR method offers a range of benefits in wastewater treatment. These benefits make this method a preferable way of treating wastewater over traditional methods like activated sludge or membrane bioreactor. Here are the major benefits of the MBBR wastewater treatment method:
The foremost benefit of the MBBR treatment is that it doesn’t require a lot of physical space. It is also a reason why MBBR is considered to have a small carbon footprint in wastewater treatment compared to its traditional alternatives.
An MBBR tank, which is much smaller than a tank used for an activated sludge or trickling filter method, can treat the same amount of wastewater flow.
MBBR is highly suitable for industrial plants that have space constraints. When the wastewater treatment method occupies a lot of space, it means less space is available for other machinery and systems essential for production. However, MBBR systems resolve this problem.
If a facility has to expand its existing systems to treat a larger volume of wastewater, MBBR tanks are a wonderful choice to consider because they can be simply added to the existing system without taking up a lot of room. Existing tanks can also be retrofitted to use as MBBR aeration tanks.
The biofilm-based reactors are highly easy to operate. The science behind it may seem complex, but the process is quite straightforward.
The manufacturing plants that produce wastewater must consider numerous aspects while determining the most effective design for their MBBR system. These parameters include surface area loading rate (SALR), wastewater flow rate, nitrate, ammonia, or BOD content. These criteria can help establish the required carrier surface area and tank volume for a successful MBBR process. The calculations vary depending on whether the goal is single- or two-stage BOD removal, single-stage nitrification, two-stage BOD removal and nitrification, post-anoxic or pre-anoxic denitrification.
After determining the right design, it is easy to operate the system. Since there is high flexibility in the system, it can easily respond to changes on its own, and the operator rarely needs to make any adjustments.
Another major advantage of the MBBR systems is that it requires low maintenance. Thus, many industrial facilities prefer this as they have to spend less on maintenance activities. On the other side, many other biological-based water treatment systems require maintenance action for a smooth process; MBBR systems tend to function efficiently and effectively on their own with little intervention.
MBBR systems have high flexibility and can easily adjust to varying loads. This means that they can resist shock loads effectively. Because MBBR systems combine the advantages of fixed film and suspended growth biological processes, they can withstand high organic loads without being undone by a shock load or any extreme change, such as a transient surge in pH levels.
Hydraulic Retention Time (HRT) refers to how much time a wastewater treatment system takes for treatment. It can be high for many systems, which indicates slowness. If the process is slower, less water can be fed at a given point in time for the treatment.
MBBR systems are designed to work rapidly, resulting in a relatively low HRT. MBBR systems typically have an HRT of a few hours or less. This low HRT is possible because of the continually moving media and high biofilm concentration.
Because MBBR systems operate so quickly, a facility may process more wastewater per day with an MBBR system than with another type of system with the same capacity. Returning to the argument regarding an MBBR’s lower footprint, this means that a smaller system can treat more water on a shorter timescale than equivalent systems. This makes MBBR systems a highly efficient option.
MBBR is a versatile wastewater treatment option that can be used across diverse industries. Here are the major ones:
MBBR is highly used in treating municipal wastewater. It makes it easier to remove organic matter, nitrogen, and phosphorous from wastewater.
Industries such as textile, chemical, pharmaceuticals, manufacturing, pulp & paper, and others can also use MBBR technology for wastewater treatment. It can effectively treat diverse types of industrial pollutants, including organic compounds, toxic substances, and high-strength wastewater.
Processing dairy products such as milk, cheese, and yoghurt generates a substantial amount of effluent, which contains biochemical oxygen demand (BOD) and other pollutants. MBBR is an excellent wastewater treatment option for the dairy industry due to its high efficiency.
MBBR systems are highly effective for treating wastewater generated by food & beverage processing facilities. MBBR technology can remove organic compounds, suspended solids, and other contaminants.
In this article, we have explored various aspects of the MBBR technology and how it helps in achieving high performance due to its smaller size.
At Wiprowater, we provide high-quality MBBR wastewater systems with technical-grade equipment that are also compact in size. Our experts have advanced knowledge of hydrodynamics, biofilm, and aeration integration. We offer customized wastewater treatment systems to fit the needs of any wastewater treatment facility.