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깊이 32m인 심층포기장치에서 기포(氣泡)의 형태(形態)와 거동(擧動)에 관하여 실험연구(實驗硏究)를 실시하였다. 연구(硏究) 결과(結果)에 의하면, 심층포기장치의 하향관(下向管)에 설치된 0.06cm의 단일(單一) 오리피스경(經)에서 발생되는 기포(氣泡)의 구체적(球體積) 상당경(相當經)(Dv)은 0.422-0.722cm이고 기포(氣泡)의 형상(形狀)은 타원체(?圓體)이었다. 기포(氣泡) 체류량(滯留量) 기(氣)-액(液) 접촉면적(接觸面積)은 심층포기장치의 수심(水深) 증가(增加)할수록 감소(減少)하였으며, 기포(氣泡)의 하강속도(下降速度)는 액체(液體)의 순환(循環)유속보다 작고, 기포(氣泡)의 상승속도(上昇速度)는 액체(液體)의 순환(循環)유속보다 약간 크게 나타났다. 심층포기장치내의 기포분포(氣泡分布)는 거의 대수정정규분포(代數定定規分布)를 나타내고 있으며, 또한 기포(氣泡)의 갯수는 수심(水深)이 증가(增加)할수록 감소(減少)하며, 하향관(下向管)이 상향관(上向管)에 비하여 많았다. The experimental study on the shape and behavior of bubbles in U-tube deep shaft of 32m has been performed. According to the results in this paper, the equivalent spherical diameter of bubbles was 0.422-0.722cm and the shape of bubbles was almost ellipsoidal for bubbles to be generated ta single-orifice of diameter 0.06cm in the downcomer of the deep shaft system. Gas hold-up and gas-liquid contact area of bubbles in the deep shaft was decreased in accordance with depth, Also downcomer velocity of bubbles was slower than circulation velocity of liquid and riser velocity of bubbles was fast than circulation velocity. The bubble-size-distribution of bubbles in the deep shaft was the logarithmic probability distribution. The number of bubbles in the deep shaft was decreased in accordance with depth and the number of bubbles in the downcomer is more than the bubbles in the riser.
An experimental study on the oxygen transfer characteristics in a U-type deep shaft system of 32m depth as an aeration tank has been performed. According to the results of this study, total over-all oxygen transfer coefficient(K_La) in downcomer had calculated to be 45.8∼174.7/hr. Oxygen transfer ability in this deep shaft system was higher than diffused aeration, since oxygen transfer rate was 0.7∼1.8 ㎏-O₂/㎥ hr and oxygen dissolution efficiency was 17.3-6.1%, average oxygen transfer efficiency was 2.25 ㎏-O₂/Kw ·hr.
활성(活性)슬러지법(法)에 의하여 고농도(高濃度) 유기성(有機性) 폐수(廢水)를 처리(處理)할 경우에 발생(發生)되는 문제점(問題點)은 폭기조내(曝氣槽內)의 미생물농도(微生物濃度)와 산소전달능력(酸素傳達能力)이 제한(制限)받고 있는 점이다. 이러한 문제점(問題點)을 극복(克服)하기 위하여 높은 산소전달능력(酸素傳達能力)을 나타내는 심층폭기(深層曝氣) 활성(活性)슬러지법이(法) 폐수처리현장(廢水處理現場)에 적용(適用)되고 있다. 따라서 본(本) 연구(?究)는 심층폭기(深層爆氣) 활성(活性)슬러지법(法)의 액체순환특성(液體循環特性)과 산소전달특성(酸素傳達特性) 및 제지폐수(製紙廢水)의 유기물(有機物) 제거특성(除去特性)에 대하여 연구(?究)하게 되었다. 연구결과(?究結果), 심층폭기장치(深層曝氣裝置)는 일반(一般) 산기식(散氣式) 폭기장치(曝氣裝置)에 비하여 산소전달능력(酸素傳達能力)이 매우 높고 순산소(純酸素) 폭기법(曝氣法)과 거의 같은 산소전달특성(酸素傳達特性)을 나타낸다. 또 폭기조내(曝氣槽內) 미생물농도(微生物濃度)와 유기물부하(有機物負荷)를 높게 유지할 수 있어 고농도(高濃度) 유기성(有機性) 폐수(廢水)를 처리(處理)할 수 있었다. A generated problem in treated highly concentrated organic wastewater by activated sludge process is the limitation of biomass concentration and oxygen transfer capability in aeration tank. To overcome the limitation, the deep shaft activated sludge process which has high oxygen transfer capability was applied to the wastewater treatment process. This paper investigated the characteristics of liquid circulation, oxygen transfer and biological treatment of paper mill wastewater by the deep shaft activated sludge process. From the obtained results, it was found that the oxygen transfer capability in the deep shaft system was much greater than those in the conventional aeration systems and almost tantamount to the pure oxygen system. The deep shaft system could treat highly concentrated organic wastewater by higher biomass concentration and organic loading rate.
This investigation was the study on the water quality change and antisphate in Geum Gang reservior for management of water quality and water supply. The results that had obtained from this investigation are as follows, Geum Gang reservior will take full advantage of water supply, if achieved seperation supply of water. Water quality standard in reservior is graded Ⅱ of drinking water source because of sustained to below BOD 3.0 ㎎/ℓ from 1989 to 2001. Geum Gang reservior will generated eutrophication conditions because of nitrogen and phosphate.
This paper was the study on the change of the water quality an water quality management of reservior when Yong-dam dam constructed. The results obtained are as follows, water quality of river in surroundings area was BOD 1-2 ㎎/ℓ, TKN 1 ㎎/ℓ, T-P 0.03-0.013 ㎎/ℓ. Results from calculatin of the pollution loading of conteminations according to environmental factor, water quality was calculated to BOD 0.87 ㎎/ℓ, T-N 0.07 ㎎/ℓ. Because of increased of inlet nutrient, nutrient conditions in Yong-dam reservior will generated to eutrophication. Therefore, methods for control and management nutrition conditions are must be intercept and control to inflow of nutrient that included to water and wastewater.
This paper studied on the effective maintenance and management of water quality in Okjong reservoir. This study included the measurment of water quality in Okjong reservoir, change of water quality in Okjong reservoir due to depth and distance, nutrient and eutrophication of the reservoir and management of water quality in Okjong reservoir. The experiment results showed thst water quality in Okjong reservoir was 2nd class of environmentl standard in lake as pH was average 7.2, COD was average 1.1㎎/ℓ, SS was average 1.9㎎/ℓ, DO was average 10.6㎎/ℓ and water quality of inleted stream in Okjong reservoir was 2nd class of environmental standard in stream as pH was 7.0, BOD was 1.3-1.7㎎/ℓ, SS was 2.2-2.4㎎/ℓ, DO was 11-11.6㎎/ℓ. The change of water quality in Okjong reservoir showed that COD was 0.8-1.4㎎/ℓ, SS was 1.2-2,7㎎/ℓ due to season and temperature was 0.4-3℃ DO was 0.3-1.0㎎/ℓ due to day. Also, the change of water quality in Okjong reservoir showed that COD was 1.2㎎/ℓ, SS was 1.3㎎/ℓ, DO was 1.2㎎/ℓ due to sampling point. The nutrient in Okjong reservoir had measured that T-N was average 0.38㎎/ℓ, T-P was average 0.026㎎/ℓ, chlorophyll was average 11.2㎎/㎥ transparence was average 2.4m and showed depth of maximum concentration in chlorophyll. The nutrient condition of Okjong reservoir is going to eutrophication condition.