• 대한환경공학회지
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• 제22권4호
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• pp.619-627
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• 2000

혐기성 UASB 반웅기를 이용하여 C. I. Reactive Blue 114 생분해를 위한 운전조건을 구하고자 하였다. 운전조건의 중요한 변수로서 염료농도, 탄소원의 종류 및 농도, HRT, 유입 pH의 영향을 조사하였다. 보조탄소원인 포도당은 염료제거에 있어 휘발성 지방산보다 더 우수하였으며, 포도당 $1000{\sim}3000mg/{\ell}$ 범위에서 염료제거율에 거의 영향이 없었다. HRT가 6시간에서 24시간으로 증가하였을 때 염료제거율은 HRT 12시간까지 증가하였으며 그 이상에서는 거의 일정한 값인 40%를 유지하였다. 유입 pH가 6.0~8.0 범위에서 변화하였을 때 유출수 pH는 6.8~7.5로 나타났고, pH 7.0에서 최대 염료제거율을 보였다. 본 연구에서 획득한 최대 염료제거속도는 $52mg/{\ell}{\cdot}day$이었지만 색도 환경기준치를 만족하는 최대 염료부하량은 $46mg/{\ell}{\cdot}day$로 나타났고, 이때의 운전조건은 HRT 12시간, 포도당 농도 $2200mg/{\ell}$이었다.

• Environmental Engineering Research
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• 제23권3호
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• pp.288-293
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• 2018

The main objective of this study is to investigate the influence of hydraulic retention time (HRT) on biogas production during leachate treatment using an anaerobic reactor type Upflow Anaerobic Sludge Blanket. For this purpose, four HRTs ranging from 12 to 48 h were experienced. The obtained results showed that higher amount of biogas could be produced during longer HRTs. However, HRTs longer than 48 h could not affect clearly the biogas generation and considered as unnecessary given the small additional amount of biogas produced during the degradation process. A volume of $0.434L/L_{leachate}/d$ was achieved during the treatment with a HRT of 48 h. The higher biogas production, the smaller chemical oxygen demand (COD) values achieved. Besides, COD removal and biogas production positively correlate, showing that the active biomass has degraded effectively the organic load to produce biogas. Moreover, all the analyzed physicochemical parameters have experienced a decrease after 48 h except for the pH, which increased to approximately neutral value. More precisely, a decrease of 93.8%, 89.7%, 95%, 70%, 77%, and 84.4% was recorded for COD, electrical conductivity, total suspended solid, turbidity, $NH_4{^+}-N$, and $NO_3{^-}-N$, respectively.

• 한국물환경학회지
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• 제21권6호
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• pp.643-650
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• 2005

In order to treat leachate from aged landfill site effectively, removal of biologically recalcitrant organic matter and denitrification efficiency were evaluated through the combination of $H_2O_2/O_3$ AOP pretreatment process and UASB process. The results can be summarized as follows. In case of leachate having low COD/N ratio from aged landfill site, it is possible to increase available COD for denitrification in nitrate utilizing denitrification and nitrite utilizing denitrification both by enhancing biodegradability of recalcitrant organic matter as applying $H_2O_2/O_3$ AOP to pretreatment process. In this experiment, it is found that available COD for denitrification can be increased to 1.0 and 0.4 g/day, respectively. Comparison has been made between requiring COD and available COD for denitrification in each experimental stages. It is expected that high rate of denitrification can be achieved with leachate from young landfill site because higher amount of available COD for denotrification is present in the leachate than the amount of requiring COD for denitrification. Especially, In leachate from aged landfill site with low COD/N ratio, it can be concluded that denitrification using nitrite nitrogen can enhance overall denitrification performance efficiently because denitrification using nitrite nitrogen requires less amount of carbon source than denitrification using nitrate nitrogen. Comparing the biogas production rate and nitrogen content of biogas under the condition of same amount of nitrate and nitrite addition, biogas production and nitrogen content of biogas are increased during denitrification after $H_2O_2/O_3$ AOP pretreatment process. Therefore, it can be confirmed that COD/N ratio in the leachate is increased. Applying $H_2O_2/O_3$ AOP as pretreatment system of landfill leachate seems to have little economic benefit because it requires additional carbon source to denitrify ammonia nitrogen in leachate coming from aged landfill site. However, it is possible to apply this pretreatment process to leachate from old landfill site in view of AOP process can achieve removal of biologically recalcitrant organic matter and increase of available COD for denitrification simultaneously.