Membrane Bioreactor를 이용한 폭발성 물질의 가수분해 부산물의 탈질과정에의 적용

조경덕 ( Kyung Duk Zoh ) 한국물환경학회 2002 한국물환경학회지 Vol.18 No.2

A bench-scale anoxic membrane bioreactor (MBR) system, consisting of a bioreactor coupled to a ceramic crossflow ultrafiltration module, was evaluated to treat a synthetic wastewater containing alkaline hydrolysis byproducts (hydrolysates) of RDX, The wastewater was formulated the same as RDX hydrolysates, and consisted of acetate, formate, formaldehyde as carbon sources and nitrite, nitrate as electron accepters. The MBR system removed 80 to 90% of these carbon sources, and approximately 90% of the stoichiometric amount of nitrate, 60% of nitrite. The reactor was also operated over a range of transmembrane pressures, temperatures, suspended solids concentration, and organic loading rate in order to maximize treatment efficiency and permeate flux. Increasing transmembrane pressure and temperature did not improve membrane flux significantly. Increasing biomass concentration in the bioreactor decreased the permeate flux significantly. The maximum volumetric organic loading rate was 0.72 kg COD/㎥/day, and the maximum F/M ratio was 0.50 kg N/kg MLSS/day and 1.82 kg COD/kg MLSS/day. Membrane permeate was clear and essentially free of bacteria, as indicated by heterotrophic plate count. Permeate flux ranged between 0.15 and 2.0 ㎥/㎡/day and was maintained by routine backwashing every 3 to 4 day. Backwashing with 2% NaOCl solution every fourth or fifth backwashing cycle was able to restore membrane flux to its original value.

Fenton 산화에 의한 폭발성 물질 (RDX , HMX) 의 처리 연구

조경덕(Kyung Duk Zoh) 大韓環境工學會 2001 대한환경공학회지 Vol.23 No.9

정수처리 과정에서의 미량오염물질의 거동 및 제거 특성

남승우,조경덕,Nam, Seung-Woo,Zoh, Kyung-Duk 한국환경보건학회 2013 한국환경보건학회지 Vol.39 No.5

Micropollutants emerge in surface water through untreated discharge from sewage and wastewater treatment plants (STPs and WWTPs). Most micropollutants resist the conventional systems in place at water treatment plants (WTPs) and survive the production of tap water. In particular, pharmaceuticals and endocrine disruptors (ECDs) are micropollutants frequently detected in drinking water. In this review, we summarized the distribution of micropollutants at WTPs and also scrutinized the effectiveness and mechanisms for their removal at each stage of drinking water production. Micropollutants demonstrated clear concentrations in the final effluents of WTPs. Although chronic exposure to micropollutants in drinking water has unclear adverse effects on humans, peer reviews have argued that continuous accumulation in water environments and inappropriate removal at WTPs has the potential to eventually affect human health. Among the available removal mechanisms for micropollutants at WTPs, coagulation alone is unlikely to eliminate the pollutants, but ionized compounds can be adsorbed to natural particles (e.g. clay and colloidal particles) and metal salts in coagulants. Hydrophobicities of micropollutants are a critical factor in adsorption removal using activated carbon. Disinfection can reduce contaminants through oxidation by disinfectants (e.g. ozone, chlorine and ultraviolet light), but unidentified toxic byproducts may result from such treatments. Overall, the persistence of micropollutants in a treatment system is based on the physico-chemical properties of chemicals and the operating conditions of the processes involved. Therefore, monitoring of WTPs and effective elimination process studies for pharmaceuticals and ECDs are required to control micropollutant contamination of drinking water.

철 석출장치에 의한 폐수 중의 인 제거 특성

조일형,조경덕,안상우,장순웅,김영규,Cho Il-Hyoung,Zoh Kyung-Duk,An Sang-Woo,Chang Soon-Woong,Kim Young-Kyu 한국환경보건학회 2006 한국환경보건학회지 Vol.32 No.1

This study was conducted to improve an effect of phosphorus removal using FNR(Ferrous Nutrient Removal) process which had iron precipitation reactor and to analyze the iron corrosion. For simultaneous removal of phosphorus, iron electrolysis was combined with oxic tank. In this study, The removal efficiency of phosphorus increased with an increase voltage in iron precipitation reactor. The distance of 15mm between the two iron bed in each tests influence the concentration of remaining phosphorus most. The extensive surface area of iron bed is the more removes the phosphorus. In this test the $400\;cm^2$ of surface area was proved to be the most removal efficient.

담수 환경에서의 미세플라스틱 검출 및 위해성 평가에 관한 고찰

김문경(Moon-Kyung Kim),조경덕(Kyung-Duk Zoh) 서울대학교 보건환경연구소 2019 보건학논집 Vol.56 No.1

Microplastics (MPs), a plastic debris with a particle diameter of less than 5 mm, are a pollutant of environmental concern and have received attention in recent years. The effects of MPs on the human body and the cause of their occurrence have not been clarified, but there is no doubt that the concentration in the natural environment surrounding human life is increasing. Therefore, it is necessary to make efforts to establish the basis of MPs investigation system and risk. In the future, various researches should be carried out in order to establish scientific basis such as investigation of source and contamination status of MPs at the national level, the degree of bioaccumulation and influence of MPs emitted into aquatic ecosystem, and the harmfulness of MPs themselves. In this study, we intended to look into other studies on the collected sampling methods, pretreatment methods, and analysis methods in order to help better understand MPs in freshwater. In addition, we reviewed relating to the potential environmental risks and impacts on MPs in the freshwater environment, and proposed the risk assessment models of MPs in freshwater environments. This study will be helpful to the future research on the monitoring system, human health risk, and development of environmental policies to manage the MPs pollution.

전기응집 반응을 이용한 PFOA의 제거에 관한 연구

김문경 ( Moon-kyung Kim ),김태연 ( Taeyoun Kim ),김태경 ( Tae-kyoung Kim ),조경덕 ( Kyung-duk Zoh ) 한국물환경학회(구 한국수질보전학회) 2018 한국물환경학회·대한상하수도학회 공동 춘계학술발표회 Vol.2018 No.-

수영장 욕조수의 소독방법에 따른 THMs 발생 특성

이진,하광태,조경덕,Lee Jin,Ha Kwang-Tae,Zoh Kyung-Duk 한국환경보건학회 2006 한국환경보건학회지 Vol.32 No.2

The objectives of this study were to investigate the formation of trihalomethanes(THMs) and to compare the concentration level of THMs of swimming pools water by different disinfection methods such as chlorine, ozone-chlorine, and salt brine electrolysis generator (SBEG). The concentration of chloroform was the highest in the chlorine system, and the SBEG was the highest in the production of bromodichloromethane (BDCM), dibromochloromethane (DBCM) and bromoform. The average concentration of total trihalomethanes (TTHMs) in three disinfection systems were $64.5{\pm}27.4mg/l(SBEG),\;43.8{\pm}22.3mg/l(chlorine)$, and $30.6{\pm}16.1mg/l(ozone-chlorine)$, respectively. In chlorine and ozone-chlorine disinfection system, chloroform concentration was highest, followed by BDCN, then DBCM. In the SBEG, TTHMs was composed of 42% of chloroform, 28.9% of bromoform, 15.1% of BDCM and 14% of DBCM, respectively. The strongest correlation was obtained in the levels of chloroform and TTHMs in chlorine, and ozone-chlorine disinfection systems from both indoor and outdoor swimming pools ($r=0.989{\sim}0.999$, p<0.01). In the SBEG, the levels of BDCM and TTHMs showed a good correlation (r=0.913, p<0.01). In chlorine and ozone-chlorine disinfection systems at indoor swimming pools, pH, TOC and $KMnO_4$ consumption showed strong correlation with chloroform and TTHMs concentrations (p<0.01). In the SBEG, pH and TOC were also strongly correlated with chloroform (p<0.01). pH and TTHMs were correlated as well (p<0.05).

녹조현상에 의하여 배출되는 이취미물질 및 독성물질의 배출 및 제어에 대한 고찰

김문경(Moon-Kyung Kim),문보람(Boram Moon),김태경(Tae-Kyoung Kim),조경덕(Kyung-Duk Zoh) 서울대학교 보건환경연구소 2015 보건학논집 Vol.52 No.1

The purpose of this study is to review the production and treatment of harmful substances (i.e., microcystins) and taster and odor substances (i.e., 2-MIB, geosmin) of hazardous compounds from algal bloom events. The classical treatment processes in water treatment plants were discussed. To effectively treat these harmful compounds, the classical water treatment processes including coagulation, chlorination, and activated carbon adsorption were discussed. As an alternatives for treating these compounds, advanced oxidation processes (AOPs) were also discussed. Ultimately, this study would give us the important information to minimize the formation of these harmful substances or other organic byproducts mediate from algal bloom.

환경매체에서의 수은의 거동과 인체 노출

김문경(Moon-Kyung Kim),조경덕(Kyung-Duk Zoh) 서울대학교 보건환경연구소 2013 보건학논집 Vol.50 No.1

Mercury is difficult to be degraded in the environment, and can be emitted to the atmosphere from various natural and anthropogenic sources such as incineration, and transported to other environmental media. Mercury exists as various species, mainly elemental (Hg<SUP>0</SUP>) and dissolved (Hg<SUP>2</SUP>) mercury depending on its oxidation states in air and water environments. Mercury emitted to the atmosphere can deposit into water environment mainly by wet and dry depositions, but some amounts can be reemitted to the atmosphere. Mercury species in water environment can react with organics in water and sediment by biotic and abiotic reactions, and converted into organic mercury, mainly methylmercury (MeHg). Methylmercury (MeHg) are bioaccumulated into food web in the ecosystem, finally exposed into humans. this review paper summarized the mechanisms of mercury emission, fate and transport, speciation chemistry, the levels of pollution, and exposure routes to humans for better understanding of how humans are exposed to the mercury from the environment.

주성분분석을 이용한 환경영향평가와 사후환경조사의 비교 및 평가에 관한 사례연구

조일형,김용섭,조경덕,Cho Il-Hyoung,Kim Yong-Sup,Zoh Kyung-Duk 한국환경보건학회 2005 한국환경보건학회지 Vol.31 No.2

Environmental monitoring system has been adopted and supplemented as inspection measures for the quantitative and qualitative changes of environmental impact assessment (EIA). This study compares the results of environmental impact assessment with the results of post-environmental investigation using a correction and principal component analysis (PCA) in the housing development project. Correlation analysis showed that most of air quality variables including TSP, $PM_{10},\;NO_2$, CO were linearly correlated with each other in the environmental impact assessment and the post-environmental investigation. In the water quality, pH and BOD were well correlated with the DO and SS, respectively. As a result of correlation analysis in the noise and vibration, noise in day and night and vibration in day and night were related to each other between EIA and the post-environmental investigation. From the results of analysis of soil, Cu with Cd, Cu with Pb, and Cd with Pb were related to each other in EIA. Principal component analysis (PCA) showed a powerful pattern recognition that had attempted to explain the variance of a large dataset of inter-correlated variable with a smaller set of independent variables (principal components). Principal component (PC1) and principal component (PC2) were obtained with eigenvalues> 1 summing almost $90\%$ of the total variance in the all of the items(air, water, noise, vibration and soil) in EIA and post-environmental investigation.