SEWAGE TREATMENT DEVICE

PROBLEM TO BE SOLVED: To provide a sewage treatment device where the dissolution of oxygen is performed by the feed of fine bubbles, and further, the fine bubbles are fed and circulated even to sedimented sludge.SOLUTION: Provided is a sewage treatment device comprising: a stirring tank 1 as a tank provided with a treatment water outflow part 11 via an upper carrier outflow prevention means 15 checking the outflow of a carrier at the bottom part but allowing the outflow of treatment water and settled sludge and a sludge storage part 6 via a lower carrier outflow prevention means 28, in which many aerobic microorganisms-adhered carriers are made to stir and flow; an upper-lower pierce-shaped stirring guide tube 20 arranged at the inside of the stirring tank; an upper-lower pierce-shaped water withdrawal guide tube 24 arranged in a vertical tube type at the opening of the lower edge of the stirring guide tube; a rising flow generation means generating bubbles exceeding microbubbles; a fine bubble feed means 37 releasing microbubbles, nanobubbles or the like; a sedimented sludge re-introduction means 50; a residual sludge exhaust means; and a cleaning flow feed means 32 removing matters retaining in the lower carrier outflow prevention means and performing control so as to allow their sedimentation passage into the sludge storage part.SELECTED DRAWING: Figure 1 【課題】酸素溶が微細気泡の供給によりなされるようにするとともに沈降汚泥に対しても微細気泡を供給し循環する汚水処理装置を提供する。【解決手段】上部担体流出防止手段１５を介する処理水流出部１１が、底部に担体の流出を阻止し処理水および沈降汚泥の流出は許容する下部担体流出防止手段２８を介する汚泥貯留部６が設けた槽で、好気性微生物着生担体の多数が撹拌流動される撹拌槽１と、撹拌槽の内部に配置された上下貫通状撹拌ガイド管２０と、撹拌ガイド管の下端開口に縦管式に配置された上下貫通状揚水ガイド管２４と、マイクロバブルを超える気泡を発生させる上昇流発生手段と、マイクロバブルやナノバブルなどのを放出させる微細気泡供給手段３７と、沈降汚泥再導入手段５０と、余剰汚泥排除手段と、下部担体流出防止手段に滞留する物を除去して汚泥貯留部内への沈降通過を許容するように制御する洗浄流供給手段３２とを備えている汚水処理装置。【選択図】図１