What technology uses biological processes and media to treat wastewater?

Biofilm reactors utilize biological processes combined with media to treat wastewater effectively. In these systems, microorganisms grow on surfaces of media, creating a biofilm that facilitates the breakdown of organic pollutants in the wastewater. The biofilm can enhance the removal of contaminants through processes such as aerobic or anaerobic digestion, depending on the design of the reactor.

This technology captures the natural ability of microorganisms to metabolize organic matter while providing a stable environment for these microbes to thrive. The media in biofilm reactors provides a large surface area for microbial attachment, allowing for higher efficiencies in pollutant removal compared to traditional methods.

The other options present different methods of wastewater treatment that do not primarily rely on biological processes with media. Membrane filtration employs physical barriers to separate contaminants from water but does not utilize biological treatment mechanisms. Reverse osmosis is a membrane technology that removes dissolved solids through pressure-driven processes, while activated sludge is a biological treatment process but does not utilize media in the same way as biofilm reactors do. Thus, biofilm reactors stand out for their specific use of both biological processes and media to enhance wastewater treatment.