AEROBIC BIOLOGICAL TREATMENT DEVICE AND ITS OPERATION METHOD

To provide an aerobic biological treatment device that prevents carriers from sticking to each other resulting in agglomeration and can perform stable biological treatment for a long period of time and its operation method.SOLUTION: An aerobic biological treatment device 1 includes: a reaction tank (tank body) 2; a water-permeable plate 3 horizontally installed at a bottom of the reaction tank 2; a large-diameter particle layer 4 formed on an upper side of the water-permeable plate 3; a small-diameter particle layer 5 formed on an upper side of the large-diameter particle layer 4; an oxygen dissolution film module 6 installed on an upper side of the small particle layer 5; a receiving chamber 7 formed under the water permeable plate 3; a raw water spray pipe 8 that supplies raw water into the receiving chamber 7; a cleaning pipe 9 installed to disperse air in the receiving chamber 7, and the like. An abundance ratio of oligotrophic bacteria in aerobic microorganisms in the reaction tank 2 is adjusted to 7% or more.SELECTED DRAWING: Figure 1 【課題】担体相互の固着や集塊化を防止し、長期にわたって安定して生物処理することができる好気性生物処理装置及びその運転方法を提供する。【解決手段】好気性生物処理装置１は、反応槽（槽体）２と、該反応槽２の下部に水平に設置された透水板３と、該透水板３の上側に形成された大径粒子層４と、該大径粒子層４の上側に形成された小径粒子層５と、該小径粒子層５の上側に配置された酸素溶解膜モジュール６と、前記透水板３の下側に形成された受入室７と、該受入室７内に原水を供給する原水散布管８と、受入室７内において散気を行うように設置された洗浄配管９等を有する。反応槽２内好気性微生物における貧栄養細菌の存在比率が７％以上となるようにする。【選択図】図１