• 한국환경농학회지
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• 제29권3호
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• pp.232-238
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• 2010

본 연구에서는 UST-AF 시스템에 전(前)응집 후(後)생물학적 처리 공정을 도입하여 질소와 인을 동시에 제거하고자 하였다. 연속공정은 유기물 및 SS의 제거 효율이 90%이상으로 균등화 효과와 질산화 효율이 높았다. 호기성 여과조에서 질산화 효율이 95% 이상이었으며, 반송을 통한 탈질화 효율은 80% 이상이었다. 하수원수에 화학적 처리 공정을 도입하여 총인을 90% 이상 제거하였으며, 후속공정의 생물반응에 영향을 주지 않은 alum 주입량은 40 mg/L이었다. 그러나 하수원수에 포함된 응집제에 의한 생물반응의 저해는 관찰되지 않았으나, 향후 장기간 운전하였을 경우 공정내 축적된 응집 슬러지의 영향에 대한 고찰이 필요할 것으로 예상된다.

• 한국환경과학회지
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• 제15권2호
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• pp.133-139
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• 2006

Soil biofiltration is an environmentally-sound technology for elimination of VOCs, odorous and NOx compounds from a low concentration, high volume waste gas streams because of its simplicity and cost-effectiveness. This study was performed to evaluate effect of removal of gaseous NOx using a soil and a yellow soil. Over $60\%\;and\;48\%$ of NOx from a soil and a yellow soil was removed at the inlet NO concentrations of $423\~451$ppb, respectively. The bio-filter using a soil media was capable of purifying NOx with a different natural processes. Although some of the processes are quite complex, they can broadly be summarized as adsorption into soil pore water, and biochemical transformations by soil bacteria. When the filteration bio-reactor was applied to a soil and a yellow soil, effective NOx removal was obtained for several times and months. These results show that a soil biofilter can be of use as an alternative advanced NOx treatment system.

• 상하수도학회지
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• 제24권6호
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• pp.661-674
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• 2010

Bacterial biomass and its activity were measured in two kinds of granular activated carbon (GAC), the experimental and existing biofiltration system in a drinking water plant. The bacterial biomass was around 210 to 250 nmol P/g WW with phospholipid concentration at acclimation of ozonation treatment. The phospholipid biomass shows more or less a declining gradient along filter depth and no clear seasonality in its values. On the other hand, the microbial activity of [$^3H$]-thymidine and [$^{14}C$]-acetate incorporation within cells increased significantly along the filter depth, showing the difference of three fold between the upper and bottom layer. These factors support the different microbial composition or metabolic activity along the depth of GAC column. Turnover rates, the rate of bacterial biomass and production of biofilm, ranged from 0.26 /hr to 0.37 /hr, indicating a highly rapid recovery itself at amature state. In the non-ozonation treatment, the bacterial biomass was lower than in the ozonation and biological activity also declined towards the filter depth. The biomass levels during cessation of ozonation in the existing GAC filters were 68% of the actively ozonated state.

• 한국수산과학회지
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• 제47권5호
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• pp.622-629
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• 2014

This study induced biological denitrification and nitrification via a biofiltration process with the view of removing nitrogen from land-based fish farm effluent. To achieve this, we operated an aquaculture nitrogen-removal system that includes a denitrification and nitrification reactor [working volume 40 L, flow rate 64.8 L, HRT (hydraulic retention time) 14.8 h, HRT considering recycling of NOx 7.4 h]. In the continuous process, the nitrification rate of ammonium nitrogen exceeded 90% at a steady state and the denitrification efficiency exceeded 80% with recycling to a pre-anoxic reactor. In addition, the pH in the final effluent was lower with a low influent water alkalinity averaging 100 mg/L (as $CaCO_3$). For effective denitrification reactions, carbon must be supplied via particulate organic matter (POM) hydrolysis because of the low C/N (carbon/nitrogen) ratio in the water.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2002년도 추계학술발표회
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• pp.347-350
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• 2002

The petrochemical products can cause soil and groundwater contamination during their transportation and the use of the products, and while being contained in underground storage tanks(USTs) throughout the leakage. To treat the contaminated soil, the bioventing method is suitable for the remediation of semi-volatile compounds, such as diesel and kerosene. Biofiltration is one of possible method to treat the off-gas produced in the process of the bioventing. This study is related to the usage, effectiveness of treatment, and feasibility of two types of biofilter system made of ceramic-compost and polymer respectively to treat diesel VOCs at constant retention time of 20 sec. Compost biofilter showed the average removal efficiency of 73 % when the inlet concentration increased to 20 ppmv. Increased the inlet concentration decreased the microbial activities as well as the removal efficiency. On the contrary, the removal efficiency of the polyurethane biofilter was maintained at 88 % at the inlet concentration of 13 ppmv during ten days and was obtained to 80 % at the inlet concentration of 30 ppmv in spite of the drop of the efficiency in the sudden increase of the inlet concentration. At the beginning of the experiment it showed low removal efficiency at low inlet concentration due to the low microbial activity, however, as experiments proceed the removal efficiency could be obtained more than 80% at high inlet concentration.

• Journal of Biosystems Engineering
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• 제37권6호
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• pp.365-372
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• 2012

Purpose: Performance of slurry composting and biofiltration with methane production (SCB-M) using swine manure and sawdust was evaluated. The suitable specific liquid input (SLI) was determined at lab-scale SCB. Method: In lab-scale SCB, the SLI test was performed at liquid input rate of 0.04, 0.09, $0.17cc/cm^3$ with constant sawdust volume. In pilot-scale SCB-M, the swine manure was fed to methane digester at organic loading rate (OLR) of 0.25-0.5 g VS/L/d. The effluent from methane digester was filtered using SCB. Results: The SLI at $0.04cc/cm^3$ showed good performance in terms of retention time. In pilot-scale SCB, the removal of $NH_3$-N and total nitrogen (T-N) was found to be around 59% and 28%, respectively. Similarly, volatile fatty acid (VFA) and total chemical oxygen demand (TCOD) removal was found be 56% and 43%, respectively. Conclusions: For SCB-M process, the SLI of $0.04cc/cm^3$ is recommended. The performance of swine manure treatment was improved more by using SCB-M system than using methane digester only.

• Environmental Engineering Research
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• 제24권3호
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• pp.501-512
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• 2019

The seasonal effects on the biostability of drinking water were investigated by comparing the seasonal variation of assimilable organic carbon (AOC) in full-scale water treatment process and adsorption of AOC by three filling materials in lab-scale column test. In full-scale, pre-chlorination and ozonation significantly increase $AOC_{P17\;(Pseudomonas\;fluorescens\;P17)}$ and $AOC_{NOX\;(Aquaspirillum\;sp.\;NOX)}$, respectively. AOC formation by oxidation could increase with temperature, but the increased AOC could affect the biostability of the following processes more significantly in winter than in warm seasons due to the low biodegradation in the pipes and the processes at low temperature. $AOC_{P17}$ was mainly removed by coagulation-sedimentation process, especially in cold season. Rapid filtration could effectively remove AOC only during warm seasons by primarily biodegradation, but biological activated carbon filtration could remove AOC in all seasons by biodegradation during warm season and by adsorption and bio-regeneration during cold season. The adsorption by granular activated carbon and anthracite showed inverse relationship with water temperature. The advanced treatment can contribute to enhance the biostability in the distribution system by reducing AOC formation potential and helping to maintain stable residual chlorine after post-chlorination.

• 한국대기환경학회지
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• 제23권3호
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• pp.265-276
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• 2007

The primary objective of this study is to investigate the effect of media on the performance of biofilters. Two types of experiments were carried out in this study. The first type of experiment used a biofilter with the media composed of three different packing materials of compost, peatmoss and GAC(granular activated carbon), whereas the second type used a biofilter with the media composed of compost only. It was found from the two experiments that the biofilter composed of compost, peatmoss and GAC showed better performance than the one composed of compost only with the higher toluene removal efficiency, lower pressure drop, and more uniform media moisture content. In particular, no appreciable media compression occurred for the biofilter composed of compost, peatmoss and GAC, whereas significant media compression took place in the biofilter composed of compost only. As suggested by the other researchers, it is likely that GAC may be responsible for the higher toluene removal efficiency in the case of the biofilter composed of mixed media especially for the early stage of biofiltration due to its adsorption capability of toluene of such high concentration as 300 ppm. It was also regarded that GAC may playa major role in maintaining lower media pressure drop in the case of the mixed media than the media with compost only because of its mechanical strength resisting to the compression. Nonetheless, further refined experiments may need to draw more accurate conclusion. The results of the additional test run using the same mixed media showed that the biofilter system using the mixed media can be consistently operated for more than 100 days very stably despite sudden change in operating conditions of temperature and flow rate.

• 분석과학
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• 제31권2호
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• pp.57-64
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• 2018

The biodegradation of toluene vapor was investigated using a new type of biofilter equipped with a laboratory-scale evaporative cooler model packed with wood wool fibers (area: $360cm^2$). For the purpose of this study, the biofilter system was inoculated with Pseudomonas sp. RSST (MG 279053). The performance of this biofilter, assessed in terms of toluene removal efficiency (and elimination capacity), was as high as 99 % at a loading rate of $6g/h{\cdot}m^2$. The toluene removal efficiency decreased in an exponential manner with the increase in the loading rate. The cooler model-based biofilter was able to remove more than 99 % of toluene using Pseudomonas sp. RSST (MG 279053) as an effective inoculum. This biofilter is designed to operate under batch conditions for the removal of toluene in confined environments (e.g., automotive plants, boiler rooms in manufacturing facilities, and offshore drilling platforms).

• 한국지하수토양환경학회지:지하수토양환경
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• 제11권4호
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• pp.25-32
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• 2006

본 연구는 산기관(diffuser) 형태로 운전되는 중공사막 생물반응기(Hollow Fiber Membrane Diffuser) 시스템을 복합오염물질(benzene, toluene, p-xylene, BTX)처리에 적용해 보고, 생물반응기에 의한 각 물질의 생분해 특성을 평가하기 위하여 수행되었다. 우선 toluene을 단일오염물질로 적용한 예비 실험기간 동안에 75%수준의 안정적인 처리 효율을 확인할 수 있었다. 이후 BTX 복합오염물질을 적용한 본 실험기간 동안에도 별도의 적응기간 및 악영향 없이 70%수준의 처리효율을 얻어낼 수 있었다. 이를 통하여 toluene분해 미생물의 benzene, p-xylene의 분해 능력을 확인하였으며, toluene의 경우 복합오염물질 적용 시 다른 두 물질에 의해 소폭의 분해 저해가 발생하는 것을 알 수 있었다. 또한 분해능 실험에서 측정한 생물반응기의 BTX 분해능은 약 360 $g/m^3/hr$이었으며, 이는 기존의 생물여과공법에 제시된 최대분해능보다 높은 우수한 분해능이었다. 따라서 산기관 형태의 중공사막 생물반응기는 복합오염물질 처리에도 안정적인 운전특성을 나타내었으며, 기존의 VOCs 저감기술을 대체할 수 있는 친환경적인 기술이라고 판단된다.