Membrane bioreactors remove pollutants with advanced technology
Membrane bioreactors (MBR) use a combination of biological and membrane filtration processes to provide advanced wastewater treatment, resulting in high-quality effluent.

As with conventional treatment, MBR technology uses microorganisms to break down organic pollutants, but unlike traditional methods that rely on a clarifier to remove solids, MBR systems use membrane filtration to screen out the suspended solids, letting high-quality treated water pass through. Since there is no need for a clarifier, MBR systems typically have a smaller footprint while still providing advanced wastewater treatment that meets strict environmental regulatory standards.

Key Parameters of Water Quality
MBR technology offers an extremely efficient method of removing a wide range of pollutants from wastewater, including nutrients such as nitrogen and phosphorus that can contribute to eutrophication of freshwater systems, as well as pathogenic bacteria, suspended solids, and biochemical oxygen demand (BOD), which can compromise water quality and pose a health risk.

While the contaminant removal efficiency may be influenced by the quality of the influent, membrane pore size, and the configuration of the MBR system, a United States Environmental Protection Agency report suggests that when MBR technology is used, removal of contaminants listed under key water quality parameters is typically greater than 90% and in many cases greater than 99%.

A recent study that assessed the efficiency of MBR for treating wastewater from a fish canning factory showed removal efficiencies of 96.6% for chemical oxygen demand (COD), 98% for BOD, 99.5% for total suspended solids, 90% for nitrate, 96% for total dissolved solids, and greater than 97% for phosphorus. The Journal of Environmental Management found that in an MBR system that used dynamic membrane and ultrafiltration membrane to treat raw municipal wastewater, high removal efficiencies were achieved for total suspended solids (>99%) and chemical oxygen demand (>91%), and high removal efficiencies (>68.3->99.7%) of micropollutants such as pharmaceuticals and other chemicals were achieved.

MBR Applications and Benefits
As the water quality of MBR-treated effluent is extremely high, it can be safely discharged into the environment without fear of causing eutrophication or other ecological imbalances that can harm aquatic life. High-quality effluent that is free from pathogens and chemical micropollutants can be safely reused for nonpotable and even direct potable reuse, as it does not pose an environmental or public health risk.

Some common uses of recycled water include:

• Irrigation: Recycled water can be used on crops, landscaping, and recreational facilities such as golf courses and sports fields. Recycling wastewater reduces reliance on fresh water for crop cultivation and maintaining gardens.
• Cooling & industrial processes: Recycled water can be used as cooling water for power plants and industrial cooling towers and in industrial processes that do not require high-quality water, including manufacturing and cleaning.
• Toilet flushing: Recycled water can be used to flush toilets, helping conserve freshwater resources.
• Firefighting: Recycled water can be used to fill fire hydrants and firetrucks.
• Construction: Recycled water can be used for dust control, soil compaction, and other purposes, reducing the demand for fresh water.
• Wetland and ecosystem enhancement: Recycled water can be released into wetlands and natural habitats to support ecosystems, especially in regions facing water scarcity.
• Aquifer recharge: Recycled water can replenish groundwater that is a source for nonpotable applications and drinking water supplies.
• Direct Potable Reuse (DPR) systems: High-quality wastewater can be directly introduced into a community drinking water supply. With DPR, treated wastewater is delivered directly to the potable water distribution system, bypassing the need for discharge into a natural water body.

Comparison with Conventional Methods
MBR technology produces high-quality effluent and requires fewer steps to achieve the same results compared to conventional treatment. This means a smaller footprint, lower energy consumption, and reduced operating costs. It offers enhanced sustainability by minimizing sludge production, with a substantial reduction often surpassing 50% when compared to conventional wastewater treatment methods. The high-quality effluent can be recycled for reuse in both nonpotable and potable applications.

MBR technology is an extremely efficient, advanced wastewater treatment technology that is a game-changer for municipal and industrial applications. Contact us to learn more about MBR technology and how Seven Seas can help you finance the water infrastructure you need.