• 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.

• Journal of Korean Society for Atmospheric Environment
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• 제23권E2호
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• pp.74-81
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• 2007

Feasibility test for a biofilter was performed to treat VOCs. The applied loading rate to the biofilter was calculated between 60 to $3,700\;kg\;COD/m^3$. Trimethyl-pentene and trimethyl-hexene were the two most dominant compounds and they occupy about 85 percent. During the acclimation period, it is desirable for a biofilter to receive relatively lower VOCs concentration and flow rate, until it can adjust to new substrate and operational environment. Temperature at various points inside the biofilter reactor was observed with more than 23 temperature sensors. With steam heating, temperatures of the top sections of the media were greater than those of bottom sections. Without steam heating, intermediate stages generally had higher temperature measurement than those of bottom and top stages. Because the pH values for different biofilter materials vary significantly, measurement of the pH for the mixture of different combinations of biofilter materials is necessary. Based on the types and brands of media, the measured pH ranged from 5.38 to 9.10. The range of measured pH of different mixtures with perlite, compost, saw dust, peat moss, limestone, vermiculite was 7.05 to 8.62.

• 한국환경과학회지
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• 제14권9호
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• pp.843-849
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• 2005

The objective of this research was to investigate the removal efficiencies ofVOCs and odors with newly developed biofilter which was designed to sustain the biofilm constantly on the packed media. Initially, four types of media, for example, fiber, activated carbon, ceramic and the mixture of activated carbon and ceramic(AIC mixture J, were used for packed materials of biofilter. When ethylalcohol was selected as a test gas for media efficiency, fiber and AIC mixture had better removal efficiencies of ethyl alcohol than others. Removal efficiencies for acetaldehyde, ethyl alcohol, butylalcohol, ethylacetate and diethylamine in biofilter with fiber and AIC mixture as packed media were increased as the residence time increased. Butylalcohol, especially, showed the maximum removal efficiency among all used VOCs and odors. In case of ethyl acetate, the difference of removal efficiencies between low and high residence times was wide remarkably.

• 한국지반환경공학회 논문집
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• 제8권4호
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• pp.41-45
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• 2007

바이오필터의 운전에 있어 큰 표면적, 높은 한계 역압력을 가지고 있는 충진 담체의 선택은 매우 중요하다. 본 연구의 목적은 황산화 세균을 분리하고 분리된 황산화 세균과 바이오필터를 이용해 담체 종류에 따른 황화수소의 제거특성을 조사하는 것이며 연구결과는 다음과 같다. 1) 전남 화순의 폐탄광 폐수에서 Thiobacillus sp. IW.를 분리하였다. 2) 다양한 담체를 이용해 유입농도, 공간속도에 따른 바이오필터의 황화수소 제거특성 및 압력손실 변화 살펴본 결과 무기성 담체가 유기성 담체에 비해 우수한 성능을 나타내었다. 3) 무기성 담체 중에서는 섬유상, PU 담체가 다른 담체에 비해 우수한 성능을 나타내었다.

• Korean Chemical Engineering Research
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• 제51권1호
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• pp.127-135
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• 2013

본 연구에서는 개선된 바이오필터설계를 가지는 새로운 바이오필터의 압력강하 및 미생물 population 분포 등을 관찰하고, 같은 유효부피를 갖고 unidirectional flow (UF)를 갖는 전통적 바이오필터의 경우와 비교하였다. 개선된 바이오필터는 운전 초기 또는 정상상태의 장기운전에서 전통적 바이오필터 압력강하의 약 40~80% 이상을 감소시켰다. 미생물 population 분포는 바이오필터 담체인 폐타이어담체와 입상 활성탄의 두 경우 모두 바이오필터 top 단에서 가장 낮았고 바이오필터 밑으로 내려갈수록 미생물 population이 커졌다. 한편 폐타이어담체는 입상활성탄 담체보다 월등히 큰 미생물 population을 나타내는 미생물 콜로니 개체수(CFU counts)를 보였다. 개선된 바이오필터에서 악취가스가 $bottom{\rightarrow}up$으로 공급되는 경우에 악취가스가 $top{\rightarrow}down$으로 공급되는 경우보다 미생물 population 성장이 더욱 컸으며, 입상활성탄 담체보다 폐타이어담체에서 이 현상이 더욱 두드러졌다. 전통적 바이오필터와 개선된 바이오필터시스템 각각의 미생물 population 분포도를 비교하였을 때에, 개선된 바이오필터의 미생물 population은 전통바이오필터보다 입상 활성탄 담체와 폐타이어담체의 경우에 각각 약 15배 및 2.5배 만큼 더 고르게 분포되었다.

• KSBB Journal
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• 제15권5호
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• pp.501-506
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• 2000

A bench-scale air biofilter was evaluated for the removal of volatile organic compounds (VOCs) from a gas stream. Compost and peat were used as the biological attachment media. Biofilter operating parameters such as incoming VOCs concentrations, temperature, and packing materials were examined. After 26 days of acclimation periods, at 25$^{\circ}C$ and 45$^{\circ}C$, the biofilter removed more than 90% of 30 to 72 mg/㎥ of total VOC. After 40 days of operation, the concentrations of isoprene, toluene, and m-xylene were reduced to 96∼99, 91∼93, and 91∼93% of the original concentrations. VOC removal efficiency was not affected by the temperature. The medium pH was maintained near neutral (pH 6.5∼7.1). After 37 days of operation, the total bacteria count in the biofilter media increased to 1.12${\times}$10(sup)8 cells/g of medium.

• 청정기술
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• 제9권1호
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• pp.37-42
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• 2003

Biofiltration was successfully applied to treat a mixture of volatile organic compounds(benzene, xylene) from contaminated air stream. Immobilized Ps. oleovorans biofilter was evaluated for its value in simultaneous removal of benzene and xylene from waste air stream. The variety of operating conditions were tested to evaluate important factors such as space velocity, pH, water content, etc.

• 한국습지학회지
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• 제1권1호
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• pp.7-16
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• 1999

The objective of this study is to recover the contaminated ditch by using a biofilter filled up with waste-concrete media and vegetation bed. Two systems were tested for elimination of organic compounds, turbidity, nitrogen and phosphate. System 1 is three-stage system which consisted of one biofilter and two vegetation bed, system 2 has three-stage system consisted of one biofilter, one vegetation bed (four bed), and one media trench operated in series. In system 1, HRT of biofilter was 4 hour, and Oenanthe javanica was planted in two vegetation bed. In system 2, HRT of biofilter was varied 2 hours and Persicaria chinensis was planted on the top of the biofilter. And Oenanthe javanica, Hydrocharis asiatica, Salvinia natans were planted in four bed of a vegetation bed and the second vegetation bed of system 1 was rebuilt to a media trench bed. The elimination rate of BOD and turbidity was over 90% in both systems. The mean elimination rates 40~50%(system 1), 30~40%(system 2) for T-N and 40~50% (system 1), 30~40%(system 2)for T-P. T-N and T-P elimination performance of system 1 was a little higher(10%) than that of system 2. Results showed that vegetation bed are not efficient in reducing T-N and T-P. It was considered that HRT of vegetation bed of both systems was much lower(1~2hr) than that of conventional system(5~20days).

• 한국환경과학회지
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• 제14권11호
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• pp.1027-1033
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• 2005

The treatment of styrene vapor was carried out using the biofilter packed with loess/polyurethane composite during continuous operation of 74 days. The microorganisms were adapted within 2-3 days under the experimental conditions of inlet concentration and empty bed contact time (EBCT). At 200 sec of EBCT, the removal efficiency of styrene was 100\% with 200 ppmv of inlet concentration, while $92\%$ with 400 ppmv of inlet concentration. The biofilter showed the stable removal efficiencies of over $74\%$ under the EBCT range from 300 to 75 sec at the 150 ppmv of inlet styrene concentration. The maximum capacity of styrene removal for the biofilter packed with loess/polyurethane was $29g/m^3/hr$. During continuous operation of 74 days, pH of the drain water changed slightly and the pressure drop through the biofilter column was below $45\;mmH_2O/m$.

• 한국농공학회지
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• 제45권2호
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• pp.107-115
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• 2003

Dairy manure amended with crop and forest residues (moisture 69% wet basis, C/N 22) was composted in a 605 L pilot-scale vessel using continuous air flow (56 L/min) for 19 days. Three pilot-scale sawdust biofilters (moisture 63%, pH 5.0) were built to clean biological waste gas from the composting process. For each methods, two replicated experiments were monitored over a period of three weeks. The system was evaluated to determine the biofilter media depth that would be adequate for compost odour reduction. The compost air cleaning was measured based on ammonia gas concentration before and after passing through the biofilter. Ammonia gas removal efficiency over 3 weeks was 42, 75 and 87% at sawdust biofilter media depth levels of 202, 400 and 600 mm, respectively. Each sawdust biofilter was operated at a moisture content in the range of 60~62% (wb), a temperature from 15 to $25^{\circ}C$, an average pressure drop from 240 to 340 Pa and a detention time from 60 to 180 seconds during the biofiltration process.