| Abstract from DBPedia | The activated sludge process is a type of biological wastewater treatment process for treating sewage or industrial wastewaters using aeration and a biological floc composed of bacteria and protozoa. It uses air (or oxygen) and microorganisms to biologically oxidize organic pollutants, producing a waste sludge (or floc) containing the oxidized material. The activated sludge process for removing carbonaceous pollution begins with an aeration tank where air (or oxygen) is injected into the waste water. This is followed by a settling tank to allow the biological flocs (the sludge blanket) to settle, thus separating the biological sludge from the clear treated water. Part of the waste sludge is recycled to the aeration tank and the remaining waste sludge is removed for further treatment and ultimate disposal. Plant types include package plants, oxidation ditch, deep shaft/vertical treatment, surface-aerated basins, sequencing batch reactors (SBRs). Aeration methods include diffused aeration, surface aerators (cones) or, rarely, pure oxygen aeration. Sludge bulking can occur which makes activated sludge difficult to settle and frequently has an adverse impact on final effluent quality. Treating sludge bulking and managing the plant to avoid a recurrence requires skilled management and may require full-time staffing of a works to allow immediate intervention. A new development of the activated sludge process is the Nereda process which produces a granular sludge that settles very well.活性汚泥（かっせいおでい）とは、人為的・工学的に培養・育成された好気性微生物群を含んだ「生きた」浮遊性有機汚泥の総称であり、排水・汚水の浄化手段として下水処理場、し尿処理場、浄化槽ほかで広く利用されている。 活性汚泥のほかに浮遊物などを含んだ廃棄物は、汚泥として総称される。 (Source: http://dbpedia.org/resource/Activated_sludge) |
