Influence of phosphate on bacterial removal in columns of iron-coated sand

박성직 ( Seong Jik Park ),이창구 ( Chang Gu Lee ),김현정 ( Hyon Chong Kim ),한용운 ( Yong Un Han ),최낙철 ( Nag Chul Choi ),김성배 ( Song Bae Kim ) 한국물환경학회 ( 구 한국수질보전학회 ) 2007 공동 추계학술발표회 Vol.2007 No.-

알루미늄·철 산화물 동시피복모래에서 Bacillus subtilis의 부착

박성직(Seong Jik Park),이창구(Chang Gu Lee),한용운(Yong Un Han),박정안(Jeong Ann Park),김성배(Song Bae Kim) 大韓環境工學會 2009 대한환경공학회지 Vol.31 No.7

본 연구에서는 칼럼실험을 이용하여 알루미늄·철 산화물 동시피복모래에서 박테리아(Bacillus subtilis)의 부착에 산화음이온(질산염, 탄산염, 인산염)이 미치는 영향을 조사하였다. 실험결과, 질산염의 경우 피복모래에서의 박테리아 부착은 질산염 이온의 농도변화와 무관하였다. 질산염의 농도가 변화함에 따라(0.1, 1, 10 mM) 질량회수율은 10.9±0.2 %로 일정하였다. 탄산염의 경우 농도가 0.1 mM에서 1 mM로 증가함에 따라 질량회수율이 25.6%에서 39.0%로 증가하였고, 인산염의 경우에도 동일한 농도조건에서 50.9%에서 78.9%로 증가하였다. 이러한 현상은 박테리아 부착에 대한 탄산염과 인산염 이온의 방해효과 때문이었다. 반면, 탄산염/인산염의 농도가 1 mM에서 10 mM로 증가함에 따라 질량회수율이 각각 39.0%에서 23.8%로 78.9%에서 52.6%로 감소하였다. 이러한 현상은 탄산염/인산염의 농도증가에 따라 피복모래표면에 흡착되지 않고 수용액상에 존재하는 탄산염이나 인산염 이온이 이온강도를 증가시킴으로써 일어나는 박테리아 부착에 대한 증진효과 때문이었다. 본 실험조건에서 피복모래에서의 박테리아 부착에 미치는 영향은 인산염, 탄산염, 그리고 질산염 중, 인산염이 가장 큰 것으로 나타났다. This study investigated the influence of oxyanions (nitrate, carbonate, phosphate) on the attachment of bacteria (Bacillus subtilis) to Al-Fe bimetallic oxide-coated sand using column experiments. Results showed that bacterial attachment to the coated sand was independent of nitrate concentration. Bacterial mass recovery remained constant (10.9 0.2%) with varying nitrate concentrations (0.1, 1, 10 mM). In case of carbonate, mass recovery increased from 25.6% to 39.0% with increasing carbonate concentration from 0.1 mM to 1 mM, and mass recovery also increased from 50.9% to 78.9% at the same concentration condition in case of phosphate. This phenomenon could be attributed to the hindrance effect of carbonate and phosphate to bacterial attachment to the coated sand. Meanwhile, with increasing carbonate/phosphate concentration from 1 mM to 10 mM, mass recovery decreased from 39.0% to 23.8% and from 78.9% to 52.6%, respectively. This phenomenon could be ascribed to the enhancement effect of free carbonate/phosphate ions present in solution phase due to increasing carbonate/phosphate concentration, which increase ionic strength and thus enhance bacterial attachment to the coated sand. In our experimental conditions, the effect of phosphate to bacterial attachment to the coated sand was the greatest among phosphate, carbonate, and nitrate.

인산염의 존재 하에서 Escherichia coli의 석영 및 철피복 모래에의 부착

박성직(Seong Jik Park),이창구(Chang Gu Lee),김현정(Hyon Chong Kim),한용운(Yong Un Han),김성배(Song Bae Kim) 大韓環境工學會 2008 대한환경공학회지 Vol.30 No.6

Influence of phosphate on bacterial removal in columns of iron-coated sand

박성직 ( Seong Jik Park ),이창구 ( Chang Gu Lee ),김현정 ( Hyon Chong Kim ),한용운 ( Yong Un Han ),최낙철 ( Nag Chul Choi ),김성배 ( Song Bae Kim ) 대한상하수도학회 2007 공동추계 학술발표회 논문집 Vol.2007 No.-

This study investigated the bacterial adhesion to iron-coated sand, focusing on the effect of phosphate concentration on the removal of Escherchia coli. Bacterial mass recoveries decreased as phosphate solution increased from 76.7% to 34.1% over the range of specific phosphate concentration (0, 4, 16ppm) tested. This phenomenon can be attributed to the increment of ionic strength with increase of phosphate concentration, which results in the decrement of the thickness of the electrical double layer around the bacteria and coated sand surfaces. In iron-coated sand, however, bacterial mass recoveries increased from 2.7% to 29.2% as phosphate concentration increased. This result can be explained by phosphate adsorption. Phosphate forms inner-sphere complexes on iron-coated sand surfaces, which can lead to competitive adsorption with bacteria on iron-coated sand.

물 재배시 비료 사용에 따른 암모니아 배출 특성

박성직(Seong-Jik Park),김건엽(Gun-Yeob Kim),이연진(Yeon-Jin Lee),조은지(Eun-Ji Cho),이재인(Jae-In Lee),임은채(Eun-Chae Im) 대한환경공학회 2022 대한환경공학회 학술발표논문집 Vol.2022 No.11

액상 비료를 유도 용액으로 사용하는 정삼투 기반의 해수 담수화

박성직,안희경,Park, Seong-Jik,An, Hee-Kyung 한국농공학회 2013 한국농공학회논문집 Vol.55 No.2

The present study explored the way to desalinate seawater for agricultural irrigation using forward osmosis (FO) process using liquid fertilizer as draw solution. FO experiments were performed in a cross flow mode using flat sheet FO membrane. The effect of membrane orientation, flow rate, and draw solution concentration on the performance of forward osmosis was investigated by measuring water flux of forward osmosis membrane. The water flux when the draw solution was placed against the membrane active layer was lower than the water flux when the feed solution was placed against the membrane active layer. This results indicated that the decrease of effective osmotic pressure by dilutive internal concentration polarization was less than that by concentrative internal concentration polarization. Increasing flow rate from 66.7 to 133.1 $cm^3$/min resulted in increase of the water flux when the membrane active layer orient to draw solution and feed solution, respectively. The reduction of resistance to water flow increased water flux at higher flow rate. The water flux of FO membrane increased with increasing draw solution concentration from 10000 to 30000 mg/L. The water flux for $KH_2PO_4$ draw solution was similar to that for commercial fertilizer. Optimization of FO process would contribute to economically desalinate brackish water for agricultural use.

지화학적 불균질 매질체에서 박테리아 부착에 관한 연구

박성직 ( Park Seong-jik ),이창구 ( Lee Chang-gu ),김성배 ( Kim Song-bae ) 한국농공학회 2007 한국농공학회 학술대회초록집 Vol.2007 No.-

This study investigated the transport of bacteria through goethite-coated sand, focusing on the effects of coated sand content on the transport of Escherichia coli ATCC 11105. Column experiments was performed in columns (length 30cm, diameter 2.5cm) with varying coated sand contents ranging from 0 to 100%. Results indicate that the mass recovery decreased from 76.7 to 2.7% as the coated sand content increased from 0 to 100%, showing the nonlinear dependency of mass recovery on the content of coated sand. This study demonstrates the importance of the coated sand content in the adhesion of bacteria to goethite-coated sand and furthermore contributes to the knowledge of bacterial removal in positively-charged porous media.

서울 신교통카드 시스템 개발과정과 도입효과 분석

박종헌,나용제,음성직,Park, Jong-Heon,Na, Yong-Je,Eum, Seong-Jik 대한교통학회 2005 교통 기술과 정책 Vol.2 No.2

고온 처리된 활성알루미나를 이용한 불소 제거

박성직(Seong Jik Park),김재현(Jae Hyeon Kim),이창구(Chang Gu Lee),박정안(Jeong Ann Park),최낙철(Nag Choul Choi),김성배(Song Bae Kim) 大韓環境工學會 2010 대한환경공학회지 Vol.32 No.10

본 연구에서는 열처리한 활성알루미나의 불소흡착특성을 분석하였다. 이를 위하여 평형 및 동적 흡착실험을 수행하였고, 용액 pH의 영향과 음이온의 존재에 따른 흡착 특성을 살펴보았다. 또한, 열처리한 활성알루미나의 여재특성을 분석하기 위하여, 전계방출주사현미경(field-emission scanning electron microscope), energy-dispersive spectrometry, X선 회절(X-ray Diffractometer, XRD)분석, 그리고 Brunauer-Emmett-Teller (BET) 비표면적 분석을 수행하였다. 다양한 온도(100, 300, 500, 700℃)에서 열처리한 활성알루미나의 흡착능을 비교한 결과, 높은 불소 농도(50, 100, 200 mg/L)에서 열처리 온도가 높아짐에 따라서 활성알루미나의 흡착량이 증가하는 것으로 나타났다. 특히, 불소 초기농도 200 mg/L에서는 700℃에서 고온처리한 활성알루미나(AA700)의 흡착량이 열처리하지 않은 활성알루미나(UAA)보다 3.67배 큰 것으로 나타났다. AA700과 UAA의 BET분석결과, UAA의 단위질량당 비표면적이 AA700의 비표면적보다 약 2배 큼을 알 수 있었다. XRD 분석결과에 의하면, AA700의 결정구조는 Al₂O₃인 반면, UAA는 boehmite (AlOOH)와 bayerite (Al(OH)3)가 혼합된 형태로 구성되어 있었다. 열처리에 의하여 비표면적이 감소하였음에도 불구하고, AA700의 불소 흡착능이 UAA에 비하여 증가한 이유는 결정구조의 변화 때문으로 판단된다. AA700의 동역학적 흡착실험결과, 불소의 흡착은 24 h 경과 후에 평형에 도달하였다. 또한, 평형 흡착실험결과에 의하면, 여재 당 불소의 최대 흡착량은 5.70 mg/g으로 나타났다. 용액 pH의 영향을 분석한 결과, pH 7에서 불소 흡착이 가장 높았으며, 산성과 알칼리성에서는 불소 흡착이 감소하는 것으로 나타났다. 음이온의 영향을 분석한 결과, 인산염, 질산염, 중탄산염은 불소 흡착을 감소시키는 것으로 나타났다. 본 연구에 의하면, 상용화된 활성알루미나를 이용하여 불소를 제거할 경우, 고온처리를 통하여 활성알루미나의 흡착능을 증가시킬 수 있을 것으로 판단된다. In this study, sorption characteristics of thermally treated activated alumina (AA) for fluoride were investigated. Sorption experiments have been conducted in equilibrium and kinetic batch conditions. Also, effects of solution pH and anions on fluoride removal have been observed. The properties of thermally treated (700℃) activated alumina (AA700) and untreated activated alumina (UAA) were compared using field-emission scanning electron microscope, energy-dispersive spectrometry, X-ray diffractometer (XRD) analysis, and Brunauer-Emmett-Teller (BET) analysis. From the experiments using AA thermally treated at different temperatures (100, 300, 500, 700℃), it was found that at high fluoride concentrations (50, 100, 200 mg/L) the sorption capacity of thermally treated AA increased with increasing thermal treatment temperature. At an initial fluoride concentration of 200 mg/L, the sorption capacity of AA700 was 3.67 times greater than that of UAA. The BET analysis showed that the specific surface area of UAA was about 2 times larger than that of AA700. The XRD analysis indicated that UAA was composed of both boehmite (AlOOH) and bayerite (Al(OH)3) while AA700 was Al₂O₃. The reason that fluoride sorption capacity of AA700 increased despite of decrease in specific surface area compared to UAA could be attributed to the change of crystal structure. The kinetic sorption test showed that fluoride sorption to AA700 arrived at equilibrium after 24 h. The equilibrium test demonstrated that the maximum sorption capacity of AA700 was 5.70 mg/g. Additional batch experiments indicated that fluoride sorption to AA700 was the highest at pH 7, decreasing at both acidic and basic solution pHs. Also, fluoride sorption to AA700 decreased in the presence of anions such as phosphate, nitrate, and carbonate. This study demonstrated that thermal treatment of AA at high temperature could increase its sorption capacity for fluoride.

돌로마이트로 충진된 칼럼에서 박테리아 이동에 관한 동역학적 모델 비교

박성직 ( Seong-jik Park ),이창구 ( Chang-gu Lee ),김성배 ( Song-bae Kim ) 한국농공학회 2015 한국농공학회 학술대회초록집 Vol.2015 No.-

The aim of this study was to compare kinetic models to describe the removal of bacteria (Bacillus subtilis ATCC 6633) using dolomite as a filter medium. Column experiments were performed in step injection mode under various conditions of influent bacterial concentration (0.5-2.0 g/L), flow rate (0.5-1.5 mL/min), and column length (10-30 cm). The highest percentage bacterial removal (R_e) of 75.2 ± 1.6% was obtained under the following conditions: influent bacterial concentration = 1.0 g/L; flow rate = 0.5 mL/min; column length = 20 cm. The highest column capacity for bacterial removal (q₀) of 2.126±0.067 mg/g was achieved using an influent bacterial concentration of 2.0 g/L, flow rate of 1.0 mL/min, and column length of 20 cm. Increasing the bacterial concentration and flow rate had a negative effect on R_e, whereas the q₀ values were positively affected. Increasing the column length produced a positive effect on Re, whereas q₀ declined. Simulation of the breakthrough curves (BTCs) using the Adams-Bohart, Thomas, Yoon-Nelson, and dose-response kinetic models demonstrated that the Adams-Bohart model adequately reproduced the initial part of the BTC, whereas the Thomas and Yoon-Nelson models were suitable for describing the transient stage of the BTC between the breakthrough point and saturation point. Compared to the aforementioned models, the dose-response model produced an adequate simulation of the entire BTC.