Membrane bioreactors are a newer type of aerobic treatment unit recently found more and more often in the market for small-scale effluent treatment systems.First developed in the 1960s, these units have seen significant modifications since the late 1990s resulting in a more robust and practical pretreatment unit for applications in onsite systems.ATUs pretreat effluent by adding oxygen to break down organic matter, reduce pathogens and transform nutrients in what is known as the activated sludge treatment process. Naturally occurring microorganisms consume organic material in sewage. Commonly, bacteria and other microorganisms are considered to be undesirable components of effluent, yet only
Membrane Bioreactors Offer Big Solutions for Small Places
Sep 24, 2025 | by Sara Heger |















