간행물

大田大學校 環境問題硏究所 論文集 대전대학교 환경문제연구소 논문집 Journal of The Institute of Environmental Studies

권호리스트/논문검색
이 간행물 논문 검색

권호

제14호 (2010년 2월) 9

환경자료

4.
2010.02 구독 인증기관 무료, 개인회원 유료
According to the development of GC equipment, it has been possible to analyze the low level of ambient VOCs concentration. In this study, the limit of detection and the limit of quantitation were estimated for two GC equipments of the VOCs analysis, which would contribute to improve the quality of VOCs analysis results. The results of %RSD for ten standard solutes showed a great reproducibility in terms of detection time and detection area. The limit of detection and the limit of quantitation in SRI GC appeared to be 0.175 ppb and 0.583 ppb for benzene, and 0.223 ppb and 0.743 ppb for toluene, respectively. On the other hand, The limit of detection and the limit of quantitation in FISON GC appeared to be 0.149 ppb and 0.496 ppb for benzene, and 0.094 ppb and 0.313 ppb for toluene, respectively.
4,500원
5.
2010.02 구독 인증기관 무료, 개인회원 유료
In this study, the performance of powdered activated carbon(PAC) contactor located in the Hakya water treatment plant(WTP) was evaluated. The result of tracer tests showed that the plug flow portion was more than 70 %. According to the total organic carbon(TOC) data of target WTP, there were no clear evidence that the addition of PAC contributed to the removal of organics. However, the results of jar test, conducted with the raw water taken from the Hakya WTP, proved that PAC could remove dissolved organic carbon(DOC) to some extent when the proper velocity gradient was maintained. It was estimated that the production rate of Hakya WTP, defined as the ratio of the operating flow rate to the design flow rate, was only 50 %. Because of this lower production rate, the mixing intensity in the contactor is much less than the designed value and, finally, the performance of PAC contactor was much less than what was expected.
4,000원
6.
2010.02 구독 인증기관 무료, 개인회원 유료
Constructed wetlands have been increasingly used as a low-energy 'green' technique since the mid-1990s, in the treatment of wastewater, driven by rising cost of fossil fuels and increasing concern about climate change. They are man-made systems or engineered wetland that are designed, built, and operated to emulate function of natural wetlands for human desires and needs. Among various applications of these wetlands, one area that is of significant importance is the removal of nitrogenous pollutants, to protect water environment and enable effective reclamation and reuse of wastewater. This report provides a current state of constructed wetland technology, focusing on CANON(completely autotrophic nitrogen removal over nitrite) process that existing types of wetlands, the mechanisms and kinetics of nitrogen removal, wetland design to system performance.
5,400원
7.
2010.02 구독 인증기관 무료, 개인회원 유료
Oxidation characteristics of benzene as a VOC were investigated using a fixed bed reactor system over transition metal catalysts. The transition metal catalysts were made by using transition metal nitrate reagent and various support materials such as γ-Al2O3, and TiO2. The parametric tests were conducted at the reaction temperature range of 200~500℃, benzene concentration of 2,000~3,000 ppm with space velocity of 10000 hr-1. The property analyses such as BET, SEM, TGA and the conversions of catalytic oxidation of VOC were examined. The experimental results showed that the BET surface areas of catalyst are 86.4∼167.7m2/g, the pore volumes are 0.049∼0.056cm3/g, and the average pore sizes of catalyst are 27∼44Å, which mean the meso pore. It was also found that the conversion of benzene oxidation reaction at 400∼500℃ with Cu/γ-Al2O3+TiO2 catalyst showed 90∼100%, which indicate that the transition metal catalyst with composite supports is very effective for the oxidation of benzene.
4,000원
8.
2010.02 구독 인증기관 무료, 개인회원 유료
We used a conventional activated sludge process to treat a paper wastewater, and then the effluent was treated with an ozone oxidation process as advanced process to remove non-degradable materials. It was found that the removal efficiency rates of the organic matter has been rapidly increased initially, and then it was almost constant after this period. The concentration of ozone should be recommended to maintain approximately 8.3 mg/L during this operation to keep the CODmn value below 100 mg/L and ozone contact time longer than 60 min.
4,000원
9.
2010.02 구독 인증기관 무료, 개인회원 유료
The potassium permanganate was used for manganese oxide catalyst with various methods and various processes, which manganese oxide wasused for removal of formaldehyde in flow gas. Experiments indicate that these catalyst materials are difference from each other because of raw materials used and pH values in catalysts preparation when used for formaldehyde removal. And when catalyst was prepared by using potassium permanganate and GLU or PEAunder different pH values respectively, it could have good performance in formaldehyde oxidizing purification. In this thesis, when the ratio of potassium permanganate and GLU was 5:1 for catalyst preparation, and 5 mL of nitric acid was added, the formaldehyde elimination efficiency could be maintained at 100% longer than 600 minutes. And when the ratio of potassium permanganate and PEA was 10:1 for catalyst preparation, and 5 mL of nitric acid was added, the formaldehyde elimination efficiency could be maintained at 100% longer than 705 minutes.
4,200원