anaerobic filter

In sewage treatment systems, an anaerobic filter (AF) is a form of anaerobic digester. The digestion tank contains a filter medium where anaerobic microbial populations—organisms that live in the absence of oxygen — can establish themselves. Such filters are commonly employed in the treatment of waste water. These reactors are gaining in popularity versus more established aerobic waste-water treatment systems because they produce a less solid residue{{cite journal|doi=10.1021/ol4027914 | volume=15 | title=Continuous Flow Generation and Reactions of Anhydrous Diazomethane Using a Teflon AF-2400 Tube-in-Tube Reactor | year=2013 | journal=Organic Letters | pages=5590–5593 | last1 = Mastronardi | first1 = Federica | last2 = Gutmann | first2 = Bernhard | last3 = Kappe | first3 = C. Oliver}} than do other types of filter.