What materials are commonly used to make MBBR media?

MBBR (Moving Bed Biofilm Reactor) media are made from materials chosen for their durability, chemical resistance, and ability to support biofilm growth. The most common materials used include:
High-Density Polyethylene (HDPE)
HDPE is widely used due to its excellent chemical resistance, strength, and flexibility. It is resistant to various chemicals and has a low risk of degradation in wastewater environments. HDPE is also lightweight, which helps with media movement within the reactor.
Polypropylene (PP)
Polypropylene is similar to HDPE in terms of chemical resistance and durability, with the added benefit of a higher melting point. This makes it suitable for applications with higher temperature exposure. PP also resists bacterial growth, which is beneficial for MBBR media.
Polyvinyl Chloride (PVC)
PVC is used in some MBBR systems, especially when cost is a consideration. While PVC has good chemical resistance, it is less commonly chosen compared to HDPE and PP due to its lower resistance to UV light and potential environmental concerns.
Expanded Polystyrene (EPS)
EPS is occasionally used in specific MBBR applications due to its lightweight nature, which aids in aeration and mixing. However, its mechanical strength and chemical resistance are lower than HDPE and PP.
Recycled Plastics
Some MBBR media are made from recycled plastics such as polyethylene or polypropylene, providing a more sustainable option. However, recycled materials require careful quality control to ensure they meet the necessary standards for wastewater treatment.
When selecting MBBR media, it's important to consider not just the material but also the media design, including factors like surface area, shape, and porosity. These features impact the media's ability to support biofilm growth and its performance in wastewater treatment.