오염물질에 대한 입상 활성탄의 흡·탈착 모델링

왕창근,Wang, Chang Keun,Weber, Walter J. Jr. 대한토목학회 1993 대한토목학회논문집 Vol.13 No.2

여러 오염물질 사이의 흡착 경쟁, 평형, 물질확산의 상호 연관성을 이해하는 것은 효율적인 활성탄 흡착탑 설계 및 운전을 위하여 중요하다. 흡착탑내에서의 오염물질의 확산 및 흡착 현상을 동역학적 및 수학적으로 예측하기 위하여 "Micro-Diameter-Depth Adsorption System" Technique을 개발하여 평형 및 물질확산 계수들을 측정하였다. 활성탄 입자의 외부 "Film Transfer"와 입자 내부에서의 "Surface Diffusion"을 고려한 오염 물질 사이의 흡착경쟁, 탈착, Chromatographic Displacement Effect 등을 Homogeneous Surface Diffusion Model(HSDM)을 이용하여 예측했다. p-Chlorophenol(PCP)/p-Nitrophenol(PNP)의 Breakthrough Curve에서 PCP는 PNP에 의해 Displace되는 현상을 볼 수 있었으며 HSDM은 이를 잘 예측하였다. Dodecylbenzenesulfonate (DBS)는 흡착된 DBS의 일부분이 비가역적 흡착반응을 보인다는 가정하에서 HSDM에 의해 잘 예측될 수 있었다. It is important to understand the interrelationship between adsorption, equilibrium and mass transport in efficient design and operation of the granular activated carbon(GAC) adsorption systems. In this study, the micro-diameter-depth adsorption system(MIDDAS) technique was developed to estimate equilibrium and mass transport parameters, which were utilized to simulate adsorption and mass transport phenomena dynamically and mathematically. The homogeneous surface diffusion model(HSDM) utilizing the estimated equilibrium and mass transport parameters including the film transfer coefficients and surface diffusivities from the MIDDAS technique, successfully predicted competitive adsorption, desorption and chromatographic displacement effects. In the binary solute system of p-chlorophenol(PCP) and p-nitrophenol(PNP), PCP was displaced by PNP and the HSDM could predict successfully. While the HSDM described the desorption breakthrough curves for PCP, PNP and PTS well when complete reversible adsorption was assumed, the desorption breakthrough curves for DBS could be predicted after subsequent incorporation of the degree of irreversibility into the model simulations.

오존에 의한 미량무기오염물질의 산화 제거에 관한 연구

왕창근(Chang Keun Wang),홍성수(Seong Su Hong) 大韓環境工學會 1992 대한환경공학회지 Vol.14 No.3

상수원수의 고도정수처리 공정 파일롯 운전 연구

왕창근(Chang Keun Wang),오상은(Sang Eun Oh) 大韓環境工學會 2012 대한환경공학회지 Vol.34 No.1

상수원인 K강 하류부에서의 COD (4~10 mg/L)는 매우 높으며 암모니아성질소의 농도(겨울철 3.5 mg/L) 또한 매우 높다. 암모나아 자체는 이 농도 범위에서 인체에 독성을 주지는 않지만 우리나라 먹는물 기준인 0.5 mg/L로 맞추어져야 한다. 본 연구에서는 K강 상수원을 고도처리 하고자 기존의 일반적인 상수처리공정을 수정하여 파일롯플랜트를 제작하여 운전하였다. 암모니아를 제거하고 염소소독 부산물 일부 제거를 위하여 파괴점 염소주입 및 분말활성탄 투여 공정을 응집조전공정에 넣었다. 또한 모래여과 공정 다음에 입상활성탄공정을 넣어 미량 잔류유기물을 제거하고자 하였다. 파일롯플렌트는 36 톤/일 규모이며 1년 동안 운전이 되었다. 본 수정된 공정을 통하여 암모니아를 제거하고 여러 유기물질(DOC, MBAS, UV-254 nm absorbance 등)들을 제거할 수 있었다. 유입 DOC 농도는 유입기간 동안 3~6 mg/L 계속 높았으며 1 mg/L로 낮추기 위해서는 GAC 필터의 2 m 높이는 낮은 것으로 판단되었다. 파괴점 염소주입에서 투입 염소농도가 잘 주입이 되었을 때 암모니아의 제 거는 98%이상이었으며 낮은 유리 잔류염소 농도와 분말활성탄 투여로 트리할로메탄(THM)은 낮게 검출되었다. Down Stream K River has high COD (4-10 mg/L) and high NH₃-N concentration (3.5 mg/L during winter period). Although NH₃-N itself is not reported harmful at this level, it must be removed to meet drinking water standard (0.5 mg/L). We constructed a pilot plant modifying the processes of conventional drinking water facilities. Prechlorination and powdered activated carbon (PAC) dechlorination was adopted prior to a flocculation tank to remove ammonia and prevent disinfection byproducts (DBPs) formation. Also, GAC processes was included after sand filter to remove residual DOC. This pilot having a capacity of 36 ton/day was operated for one year. The GAC processes were successful to remove ammonia and many organic pollutants (DOC, MBAS, UV- 254 nm absorbance, etc). Influent DOC concentrations were very high as 3~6 mg/L throughout the plant operation. It was impossible to achieve 1.0 mg/L effluent DOC, indicating that bed depth (2 m) should be increased to achieve more strict DOC quality standards. When Cl₂ dose was well controlled (Cl₂/NH₃-N ratio 10~11 on a weight basis), NH₃-N removal was 98% and THMs was very low possibly due to low free residual chlorine and PAC dechlorination.

파괴점 염소주입에 의한 NH3 - N 제거 및 THM 생성의 최소화를 위한 PAC dechlorination

오상은,왕창근 ( Sang Eun Oh,Chang Keun Wang ) 한국물환경학회 1997 한국물환경학회지 Vol.13 No.2

Influent NH₃-N concentration in downstream Keum River during winter period was as high as 3.5㎎/l. Although NH₃-N itself is not reported harmful at this level, it must be removed to meet drinking water quality standard of 0.5㎎/l. When high concentration of NH₃-N is not sufficiently removed during prechlorination, it is expected that too much chloramines are formed during post chlorination, and consumers` complaints are expected due to heavy smell of chloramine. Not sufficient disinfection efficiency by chloramine is also expected. Prechlorination and PAC dechlorination was adopted in the pilot plant study to prevent DBP formation by possible small amount of residual free chlorine after breakpoint. When chlorine dose is well controlled, NH₃-N removal is over 98% and THM formation is very low because of low free residual chlorine due to PAC dechlorination. In bench scale test, breakpoint appeared when Cl₂/NH₃-N ratio was 10∼11 on a weight basis and breakpoint reaction was almost completed within 10∼15min. After chlorination, PAC dose of l0㎎/l resulted in removal of 1∼1.5㎎/l free chlorine for 10 minutes. PAC reacted very slowly with NH₂Cl but very fast with free chlorine, and PAC removed more free chlorine at low pH than high pH.

논문 : 수질제어를 통한 관 내부 부식방지 기술의 정수처리공정 적용방안

서대근 ( Dae Keun Seo ),왕창근 ( Chang Keun Wang ) 대한상하수도학회 2006 상하수도학회지 Vol.20 No.4

Although final water of domestic water treatment plants almost contains highly corrosive characteristics, the countermeasures for eliminating internal corrosion of pipeline system have not been conducted yet by controlling water quality in plants. The technologies of internal corrosion control are to control water quality parameters(pH, Alkalinity, and Calcium Hardness etc.) and to use corrosion inhibitor. Under the conditions of domestic water treatment, first of all, the technologies of adjusting water quality parameters has to be considered. Otherwise, The technology of using corrosion inhibitor is favorably thought to be applied with the technology of adjusting water quality parameters in accordance with the result of availability for water treatment process. Since the technology of adjusting water quality parameter influences on other water treatment processes, the guideline of water quality management to be apt for water quality characteristic is required to be estabilished. While the selection of proper chemicals and technologies is dependent upon the raw water characteristics and water treatment process, typically, the technology of Ca(OH)2 & CO2 additions is considered more effective than other technologies in order to adjust pH and Alkalinity, increase Ca(2+) and form CaCO3 film

금강하류 상수원수의 고도정수처리 공정설계 및 운영조건 연구

최현정(Hyoun Jung Choi),왕창근(Chang Keun Wang) 大韓環境工學會 1997 대한환경공학회지 Vol.19 No.4

대전공단지역의 대기중 독성금속에 대한 위해도 평가

이진홍,윤미정,남병현,왕창근,강호,Lee, Jin Hong,Yun, Mi Jung,Nam, Byung Hyun,Wang, Chang Keun,Kang, Ho 한국환경영향평가학회 1999 환경영향평가 Vol.8 No.2

The research centers on the concentration profile and risk assessment of toxic metals for ambient air in Taejon industrial complex. Airborne concentrations of each toxic metal for risk assessment were obtained from 2-year sampling by high volume air sampler and analysis by ICP-MS and ICP-AES in the complex. The long-term arithmetic mean of human carcinogen, arsenic, hexavalent chromium and nickel subsulfide was 5.53, 2.16 and $3.46ng/m^3$ while the mean of probable human carcinogen, beryllium, cadmium and lead was 0.08, 2.35, $293.29ng/m^3$, respectively. And the long-term arithmetic mean concentration of non-carcinogenic metal, manganese was $55.91ng/m^3$. The point risk estimate for the inhalation of carcinogenic metals was $3.6{\times}10^{-5}$, which was higher than a risk standard of $10^{-5}$. About 75% of the cancer risk was to the inhalation of human carcinogen, arsenic. Thus, it is necessary to properly manage arsenic risk in Taejon industrial complex. The point hazard index by the inhalation of manganese was 1.1. Therefore, an investigation into Taejon industrial complex is needed to obtain more fine long-term concentration data for airborne non-carcinogenic metals including manganese.

CFD를 이용한 병열 배열형 상향류식 침전지 수리해석에 관한 연구(II) - 침전지 내 유입유량 균등성 향상을 위한 유입 분배수로 개선 -

박노석,김성수,최종웅,왕창근,Park, No-Suk,Kim, Seong-Su,Choi, Jong-Woong,Wang, Chang-Keun 대한상하수도학회 2014 상하수도학회지 Vol.28 No.2

In order to suggest the methodology for improving the equity of flow distribution in open channel with multiple outlet, CFD simulations were carried out for actual scale distribution channel being operated in domestic G_WTP(Water Treatment Plant). Also, before and after installing the longitudinal multi hole(diameter=250 mm, 116 holes) baffle suggested by this research, turbidity measurements data were collected for evaluating the effects of hydraulic modification for inlet flow equity. From the both results, total turbidity of settled water was lowered by 30 % and equity of flow distribution was improved about 60 % compared with before hydraulic structure modification.

EPANET 을 이용한 모델도시 상수도 관망에서의 수리 및 수질 Simulation

최재호(Jae Ho Choi),왕창근(Chang Keun Wang) 大韓環境工學會 1997 대한환경공학회지 Vol.19 No.7

대청호수계에서 TOC - HANDAI 법에 의한 유해화학물질의 생분해성 평가

강호(Ho Kang),왕창근(Chang Keun Wang),이진흥(Jin Hong Lee),진창숙(Chang Suk Jin),김은희(Eun Hee Kim) 한국물환경학회 1999 한국물환경학회지 Vol.15 No.2

Biodegradability test for several hazardous chemicals found in the watershed of Daechung reservoir was investigated by using TOC-HANDAI method that is a combined technology of River Die-away test and HANDAI method. Aniline and phenol were easily mineralized by natural water microcosm and their initial degradation rates of samples from Daechung reservoir were much faster than those from the main streams of Kum rivers. This was probably due to the numbers and the activities of participated microorganisms during their respective degradation. It is obvious that the metabolic pathways of both chemicals were different, showing that phenol started degradation immediately without any adaptation period. Bispenol A(BPA) at each sampling points was appeared to be mineralized 68∼89% of initial TOC concentration by natural water microcosm. BPA seems more recalcitrant against biodegradation than simple aromatic compounds such as aniline and phenol in natural water environments. Moreover, the remaining TOC components in BPA biodegradation considered to be refractory metabolites of BPA. Consequently it is likely that BPA showed semi-recalcitrant while aniline and phenol were biodegradable compounds in the watershed of Daechung reservoir.