Activated sludge - Activated sludge

Also known as activated sludge. It is a cotton-like brown mud (sludge floc) that is used in the biological treatment of sewage and wastewater and is inhabited by large numbers of microorganisms (activated sludge organisms), such as bacteria and protozoa. Zoogloea is known to be the main floc-forming bacterium, and it lowers the BOD. It is used to increase the metabolic activity of microorganisms under aerobic conditions such as aeration, and to treat the organic matter in the sewage by decomposing, coagulating, and precipitating it. Although it requires technologies such as precipitation removal and return, its extremely high purification capacity means that it is widely used in sewage treatment, as well as the treatment of various organic wastewater and industrial wastewater.

Source: Morikita Publishing "Chemical Dictionary (2nd Edition)" Information about the Chemical Dictionary 2nd Edition

活性スラッジともいう．汚水や廃水を生物学的に処理する際に用いられる，細菌や原生動物などの微生物群(活性スラッジ生物)が大量に生息している綿状褐色の泥(汚泥フロック)をいう．主要なフロック形成細菌としてZoogloea(ズーグレア)が知られ，BODを低下させる．エアレーションなど好気性条件下で微生物の代謝作用を高め，汚水中の有機物を分解，凝集，沈殿させて処理するために用いられる．沈殿除去や返送などの技術を要するが，非常に高い浄化能力をもつことから，下水処理から各種有機性廃水，工場廃水などの処理に広く用いられている．

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