How does MBBR work? Full description of moving bed biofilm reactor wastewater treatment plants

Summary

This video lecture introduces the MBBR (Moving Bed Biofilm Reactor) technology used in wastewater treatment plants for small to medium-scale projects. It covers the history, process, components, and applications of MBBR, comparing it with the activated sludge process. The MBBR process, which uses biofilm carriers, offers efficient treatment for organic matter, nitrogen, and phosphorus removal. Advantages include low sludge production, minimal maintenance, and the ability to handle varying wastewater loads. The technology is versatile, used in diverse industries, and provides superior treatment performance with a compact design and long media lifespan.

Takeaways

• 😀 The MBBR (Moving Bed Biofilm Reactor) process is used in wastewater treatment to improve treatment efficiency and create more compact systems compared to activated sludge processes.
• 😀 MBBR was developed in the late 1980s in Norway by Professor Harvard Othegard and is used in over 50 countries worldwide.
• 😀 MBBR is a secondary treatment process following primary treatment, which usually involves a clarifier to remove total suspended solids and some BOD (biochemical oxygen demand).
• 😀 The MBBR treatment process uses small plastic media (biofilm carriers) that move within aerated or anoxic tanks, providing surface area for biofilm formation to treat wastewater.
• 😀 Biofilms on the MBBR media consume organic matter like BOD and COD (chemical oxygen demand), reducing pollutants such as nitrogen and phosphorus.
• 😀 MBBR can be configured in stages to treat different types of pollutants, including BOD, COD, and nitrogen. Single, double, and triple-stage systems are common, depending on the treatment goals.
• 😀 MBBR systems are energy-efficient, require less land area than other treatment technologies, and have high removal rates of organic matter and nitrogen (up to 95% for BOD and COD, and 90% for nitrogen).
• 😀 The MBBR process involves different types of reactors such as denitrification tanks (anaerobic), nitrification tanks (aerobic), and BOD removal tanks. These may be configured in pre- or post-anoxic arrangements depending on the needs of the treatment plant.
• 😀 The media used in MBBR systems are highly durable, with lifespans of 15 to 20 years, and provide an excellent surface for biomass to grow, which leads to efficient wastewater treatment.
• 😀 Advantages of MBBR include low hydraulic retention time (HRT), low sludge production, minimal maintenance, and the ability to handle varying wastewater loads without significant performance issues.
• 😀 Compared to activated sludge, MBBR systems are more stable under varying loads, require less space, have lower power consumption, and provide a higher quality effluent, making them a superior option in many cases.

Q & A

What is the main goal of the MBBR technology?

The main goal of MBBR technology is to create a compact and efficient wastewater treatment plant that offers better treatment efficiency compared to traditional activated sludge systems, while minimizing space requirements.

Who developed the MBBR process and when?

The MBBR process was developed in the late 1980s by Professor Harvard Othergaard in Norway.

What are the key components of an MBBR treatment plant?

The key components include the MBBR media (biofilm carriers), aeration tanks, air blowers, air diffusers, mixers for anoxic tanks, retention screens to prevent media migration, and the sedimentation tank for sludge settling.

What is the role of the biofilm in the MBBR process?

The biofilm forms on the surface of the MBBR media and is responsible for breaking down organic matter like BOD and COD, as well as nitrogen compounds, by consuming these pollutants during the treatment process.

How does the MBBR process differ from traditional activated sludge systems?

Unlike the activated sludge process, MBBR does not require the recycling of activated sludge. It uses floating biofilm carriers in aerated or anoxic conditions, making it more compact, efficient, and capable of handling varying loads more effectively.

What are the advantages of the MBBR system over traditional wastewater treatment methods?

Advantages include lower hydraulic retention time (HRT), less space requirement, lower sludge production, better treatment efficiency, minimal maintenance, and the ability to respond to load variations and increased flow.

What are the main types of tanks used in the MBBR system?

The MBBR system typically uses two types of tanks: aerated tanks (for aerobic treatment) and anoxic or anaerobic tanks (for denitrification). The system may also include primary and secondary clarifiers for solids settling.

What types of wastewater can be treated using MBBR technology?

MBBR is primarily used for sewage treatment but can also handle wastewater from industries such as pulp and paper manufacturing, chemical production, textiles, beverages, and dairy processing.

How is nitrogen removed in the MBBR process?

Nitrogen removal in MBBR is achieved through nitrification and denitrification stages. The denitrification tank works in anoxic conditions, while nitrification occurs in aerated tanks, helping to convert nitrogen into nitrogen gas that can be safely released.

What are the disadvantages of MBBR technology?

Disadvantages include the need for skilled operators, the attraction of insects due to the wastewater environment, and the requirement for continuous monitoring to ensure efficient operation.