• 대한토목학회논문집
• /
• 제3권3호
• /
• pp.1-7
• /
• 1983

지금까지 발표되어 있는 여과공정(濾過工程)의 수학적(數學的) 해석(解析)의 결과(結果)는 범용성(汎用性)이 없고 실용적(實用的)으로 이용(利用)될 수 없는 문제점(問題點)이 있었다. 그러나 여과공정(濾過工程)을 수학적(數學的)으로 표현(表現)하는 것은 장치설계상(裝置設計上) 대단히 중요하기 때문에 본논문(本論文)은 급속여과지(急速濾過池)의 여과공정(濾過工程)을 해명(解明)하기 위하여 여층내(濾層內)의 tracer study의 결과(結果)를 정리한 것이다. 따라서 여과공정(濾過工程)을 해명(解明)하기 위해서 최대(最大)의 문제점(問題點)으로 되어 있던 억류물비퇴적량(抑留物比堆積量)을 직접(直接) 파악(把握)하는 것에 의해 Kozeny-Carman 식(式)을 보정(補正)하여 실제에 활용(活用)될 수 있는 미소여층(微小濾層)의 여과지저항식(濾過紙抵抗式)을 유도(誘導)하였다. 또 조지율(阻止率)과 비퇴적량(比堆積量)과의 상관(相關) model을 제안(提案)하고 이것을 이용(利用)해서 여과방정식(濾過方程式)을 풀고 그 값을 유도(誘導)한 여과저항식(濾過抵抗式)에 대입(對入)하여 전여층(全濾層)의 여과저항(濾過抵抗)을 구(求)하고 그 결과(結果)를 도표화(圖表化)함으로서 여과저항식(濾過抵抗式)을 이론(理論)과 실용(實用) 양면(兩面)에 넓게 활용(活用)될 수 있도록 하였다.

• 한국환경보건학회:학술대회논문집
• /
• 한국환경보건학회 2005년도 국제학술대회
• /
• pp.381-385
• /
• 2005

Characterization of particle behavior is becoming more important in performance evaluation of water treatment system as well as in operation of the system because conventional parameter, turbidity has lack of explaining ability on small sized microorganisms such like Cryptosporidium etc. Accordingly, particle counter has been introduced in evaluation and operation of the treatment system. However researches on the relationship between turbidity, particle count and/or different sand/anthracite sizes have not been concurrent. Therefore in this study, the relationship was investigated to improve performance evaluation of sand filter so as to help choosing sand/anthracite effective size as a design parameter of water treatment facility. According to the results, too small or too large effective size media filter reached to turbidity limit(0.1 NTU)earlier. However, because shallow sand layer may cause early breakthrough, the depth of sand layer should be provided enough in order to compromise water quality and productivity.

• 한국환경보건학회지
• /
• 제27권4호
• /
• pp.15-24
• /
• 2001

The objective of this study it to evaluate the microbial safety in rapid sand filters adapted in most drinking water treatment plants. The potential pathogens to cause water quality problems Are presumed to be Giardia and Gryptosporidium. They look like particles in view of their size. It has been reported that if the number of particles (larger than 2 ${\mu}{\textrm}{m}$ in water) is less than 100 per mL and its turbidity is below 0.1 NTU, it is considered as a safe water in terms of pathogens. In order to achieve such a good water quality. filter-aids (chemicals) were added to the inlet-channel of filter and their effectiveness was evaluated on the basis of water quality factors such as turbidity and particle counting. This study was conducted in she three steps of experiment: jar test. pilot plant test and real water treatment plant test (P plant in seoul). The experiment reult of the P water treatment showed that cationic polyamine was the most effective in the removal of particles and turbidity at the does of 0.25 mg/L. The turbidity without filer-aids showed in the range of 0.12 ~0.17 NTU during filtration and 0.14 NTU on the average. However. with addition of polyamine, the turbidity represented below(or less than) 0.1 NTU after 20 min in the start of filtration and kept 0.08 NTU on the average. On the other hand, as for number of particles, while no filter-aids led to the range of 111 ~270 per mL and 190 on the average, addition of polydmine led to 113 per mL on talc average, and kept below100 per mL after 20 min in the start of filtration.

• 대한환경공학회지
• /
• 제22권5호
• /
• pp.895-905
• /
• 2000

본 연구는 여재가 모래와 무연탄인 복층 중력식 급속여과법으로 BNR(biological nutrient removal) 공정 유출수를 처리할 때 여과율의 변화에 따른 오염물질 제거효율 및 여층 깊이별 처리수질을 파악하기 위하여 수행되었다. Pilot scale의 4-stage BNR 공정 유출수를 200, 300 및 400 m/day의 여과율로 급속여과시킨 결과, 처리수는 2.6 NTU 이하의 탁도를 나타내어 우리나라의 중수도 제한수질인 5.0 NTU를 만족하였다. 여과율이 200, 300 및 400 m/day로 증가함에 따라 SS 제거효율은 각각 80.6, 75.4 및 68.9%로 감소하는 경향을 보였지만, 여과수는 모든 여과율에서 유입수의 수질변화에 큰 영향을 받지 않고 평균 1.3 mg/L의 SS 농도를 보였다. 생물학적 작용에 의하여 영양염류도 제거되었는데, 200, 300 및 400 m/day의 여과율에서 질산화효율이 각각 17.4, 18.8 및 14.3%, 그리고 탈질효율이 각각 32.3, 27.7 및 21.4%로, 질산화와 탈질이 동시에 일어났다. 여과주기의 후반기에는 여층 내의 DO가 결핍됨에 따라 인의 재용출이 일어남으로써 유출수의 T-P 농도가 유입수에 비하여 6.1~21.4% 증가하였다.

• 한국환경과학회지
• /
• 제15권10호
• /
• pp.945-949
• /
• 2006

For a membrane bio-reactor, it is possible to fillet and separate activated sludge and effluent by head loss of centimeters, if non-woven fabric material is used as titration media. However, if non-woven fabric material is used to thicken high-concentration sludge, excessive sludge attachment causes the rapid decrease of flux. Mesh with fore sizes of $100{\mu}m,\;150{\mu}m,\;and\;200{\mu}m$ allows for easy separation of attached sludge. This study examined the possibility of mesh as filtration media. Existing close-flow filtration process, which requires maintaining sludge movement, makes It difficult to obtain high thickening rate. With a view of complementing this weakness, this study has made an experimental examination on how high-concentration sludge (about 3,000mg/L to 10,000mg/L) will be filtered and thickened when mesh module is submersed in the bio-reactor. Effluent flowed from the bottom of the bio-reactor by head loss of 65cm. In case of pore size of $100{\mu}m$, SS showed high recovery of 80% to 96%; therefore, it has been decided that mesh can be used as filtration media. Filtration lasted for more than 9 hours, until sludge with 9,000mg/L in MLSS concentration was thickened 9 times as dense. In the range from 3,610mg/L to 9,060mg/L in MLSS concentration, it was possible to obtain effluent with less than 2mg/L in MLSS concentration within 10 minutes.

• 상하수도학회지
• /
• 제20권6호
• /
• pp.813-822
• /
• 2006

Soluble manganese removal was analyzed as a function of filter media, filter depth, presence or absence of chlorination, and surface manganese oxide concentration in water treatment processes. Sand, manganese oxide coated sand (MOCS), sand+MOCS, and granular activated carbon(GAC) were used as filter media. Manganese removal, surface manganese oxide concentration, turbidity removal, and regeneration of MOCS in various filter media were investigated. Results indicated that soluble manganese removal in MOCS was rapid and efficient, and most of the removal happened at the top of the filter. When filter influent (residual chlorine 1.0mg/L) with an average manganese concentration of 0.204mg/L was fed through a filter column, the sand+MOCS and MOCS columns can remove 98.9% and 99.2% of manganese respectively on an annual basis. On the other hand, manganese removal in sand and the GAC column was minimal during the initial stage of filtration, but after 8 months of filter run they removed 99% and 35% of manganese, respectively. Sand turned into MOCS after a certain period of filtration, while GAC did not. In MOCS, the manganese adsorption rate on the filter media was inversely proportional to the filter depth, while the density of media was proportional to the filter depth.

• Membrane and Water Treatment
• /
• 제8권2호
• /
• pp.149-160
• /
• 2017

This study investigated effects of NaOH cleaning on the intrinsic permeability of polyvinylidene fluoride (PVDF) membranes and flux recoveries and membrane resistances under various conditions encountered during ultrafiltration in water treatment plants. The NaOH cleaning using 10,000 mg/L NaOH led to discoloration of PVDF membranes and had little effect on water flux. The NaOH cleaning was efficient in removing the fouling layer caused by humic water. However, long filtration induced a fouling layer that was not removed easily by NaOH cleaning. The lower temperature during filtration yielded rapid increases in transmembrane pressure and decreases in NaOH cleaning efficiency. The alkaline cleaning of PVDF changed the membrane properties such as the hydrophobicity and morphology. Foulant properties, operational conditions such as temperature, and chemical agents should be considered for cleaning strategies for PVDF applied in water treatment.

• 미생물학회지
• /
• 제47권2호
• /
• pp.117-123
• /
• 2011

본 연구는 human rotavirus (HRV)의 검출법을 최적화하기 위해 real-time RT-PCR과 세포 배양법을 이용하여 여러 가지 탈리 농축법을 비교 및 평가하는 것을 목적으로 하였다. 채소류 중 배추, 상추, 깻잎을 선정하여 바이러스 희석액을 접종하고 탈리액 비교를 위하여 buffer A (100 mM Tris-HCl, 50 mM glycine, 3% beef extract, pH 9.5)와 buffer B (250 mM Threonine, 300 mM NaCl, pH 9.5)를 이용하여 탈리하였고, 농축방법을 비교하기 위하여 PEG (polyethylene glycol) 침전법 또는 filtration [Nanoceram filter$^{(R)}$ (Argonide corporation)]을 이용하여 농축하였다. 또한 바이러스의 감염성 평가를 위하여 MA-104 cell을 배양하여 탈리, 농축 방법을 거쳐 회수된 HRV를 접종하고 1, 48, 72, 96, 120, 144, 168시간 후 세포를 수거하여 real-time RT-PCR을 시행하고 세포병변을 관찰하였다. 탈리 용액은 buffer A가 회수율 29.54%로 buffer B의 18.32%보다 더 뛰어난 탈리효과를 보였으며 농축방법을 비교했을 때 filtration 방법이 회수율 51.89%를 나타내며 PEG 침전법에 비해서 바이러스의 농축에 효과적이었으며 검출 소요시간이나 간단한 과정 면에서 효율적이었다. ICC/real-time RT-PCR을 시행하였을 때 세포병변 72시간 후부터 나타나기 시작했지만 Ct value는 48시간부터 감소하기 시작하여 더 빠른 시간 내에 감염성을 평가할 수 있었다. 따라서, filtration과 integrated/cell culture real-time RT-PCR을 이용하면 기존의 검출방법보다 빠른 시간 내에 바이러스 검출이 가능할 것으로 여겨진다.

• 상하수도학회지
• /
• 제29권3호
• /
• pp.337-345
• /
• 2015

Two step rapid filter system as a pre-treatment for the injected water into aquifer storage and recovery (ASR) in Korea was developed to reduce physical blockage and secure the volume of the injected water. First, single rapid sand filters with three different media sizes (0.4~0.7, 0.7~1.0 and 1.0~1.4 mm) were tested. Only two sizes (0.4~0.7 and 0.7~1.0 mm) satisfied target turbidity, below 1.0 NTU. However, they showed the fast head loss. To prevent the fast head loss and secure the volume of the injected water, a rapid anthracite filter with roughing media size (2.0~3.4 mm) were installed before a single rapid sand filter. As results, both the target turbidity and reduction of head loss were achieved. It was determined that the media size for a rapid sand filter in two step rapid filter system (i.e. a rapid anthracite filter before a rapid sand filter) was 0.7~1.0 mm. In addition, the effects of coagulant doses on the removal of natural organic matter (NOM), which might cause a biological clogging, were preliminarily evaluated, and the values of $UV_{254}$, dissolved organic carbon (DOC) and SUVA were interpreted.

• 한국산학기술학회논문지
• /
• 제10권4호
• /
• pp.857-864
• /
• 2009

본 연구에서는 겨울철 수온강하, 여름철 우천시 표류수 중의 고탁도 물질 및 봄, 가을철의 조류성장 시기 등을 고려하여 기존의 급속모래여과시스템을 이단 이층 복합여과시스템으로 개량하는 기술을 개발하는 것을 목표로 하였다. 본 기술은 기존 여과지의 개량 또는 신설 여과지 설계시 또 다른 부지의 확장 없이 기존 모래여과지를 대체하는 기술로서 하부집수장치 상부에 모래 + 활성탄 층을 두고 활성탄 층 상부에 일정한 간격의 역세 팽창층을 두고 전 처리의 개념으로 중간집수장치 위에 모래층을 두는 이단 이층 복합여과시스템을 말한다. 본 연구에서는 이단이층 복합여과시스템을 경기도 S 정수장에 소규모 파일롯 플랜트를 설치하였으며, 탁도는 INTU 이하로 안정하게 유지되었고, TOC, THMFP, HAAFP는 약 90%정도 제거되어 S정수장에 비해 약 2배 정도 높았으며, 이는 본 시스템의 하단에 충전된 활성탄층에서의 흡착 및 생물분해 효과에 기인된 것으로 판단된다.