• Journal of Korean Society of Environmental Engineers
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• v.32 no.12
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• pp.1126-1133
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• 2010

A two-stage biofilter was constructed and utilized to determine the removal efficiency when treating dynamic loading of a mixture of odorous compounds including benzene, toluene, p-xylene, ammonia and hydrogen sulfide. A yeast strain, Candida tropicalis, and a sulfur oxidizing bacterial (SOB) strain, Acidithiobacillus caldus sp., were immobilized in polyurethane media and packed in the two-stage biofilter. The experiment of dynamic loading variation was composed of (1) stepwise loading variation of all the odorous compounds (total EC test), (2) stepwise loading variation of each odorous compound, and (3) intermittent loading variation with 2-day-off and 3-day-on. The total EC test showed that the maximum elimination capacity was $61\;g/m^3/hr$ for total VOCs, and 5.2 and $9.1\;g/m^3/hr$ for ammonia and hydrogen, respectively. In addition, the inhibition between VOCs was observed when the loading of each individual VOC was varied. Especially the stepwise increase in toluene loading resulted in decreases of benzene and p-xylene removal efficiencies about 30% and 25%, respectively. However, the inhibition between organic and inorganic compounds was not observed. The intermittent loading variation with 2-day-off and 3-day-on showed that greater than 95% of the overall removal efficiency was restored in two days after the loading resumed. Consequently, the two-stage biofilter packed with immobilized microorganisms showed advantages over conventional biofilters for the simultaneous treatment of the mixture of organic and inorganic odorous compounds.

• 한국생물공학회:학술대회논문집
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• 2001.11a
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• pp.541-544
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• 2001

One of the most promising TCE treatment systems is trickling biofilter (TBF), in which monooxygenase, the corresponding enzyme for initiating growth substrate oxidation, fortuitously transforms TCE via cometabolism. TCE. however. is not easily treated by simple cometabolic biotransformation. This is mainly due to the toxicity of TCE to microbial cell and monooxygenase. In this study, we cleveloped and operated a two-stage CSTR/TBF system for the long-term continuous treatment of TCE. In the two-stage biotransfon11ation system, CSTR with cell recycle from TBR was coupled to the TBR for the reactivation of the cells deactivated during TCE degradation.

• Journal of Environmental Health Sciences
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• v.15 no.2
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• pp.59-68
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• 1989

This study was performed employing the two stage aerated submerged biofilter of media pore size 1.5cm and 2cm, and infiuent substrate concentrations were 30.25mg COD/l, 50.1mg COD/l respectively. The purpose was to determine the treatment efficiency at the low concentration infiuent, reaction order and substrate flux with application of variable-order model that was presented by Rittmann and McCarty. . The results are as follows. 1. Treatment efficiency of 1st reactor was about BOD 82% and COD 76%, when effluent concentration was BOD 3.9 ~ 6.8, COD 7.1 ~ 12.5 mg/l, and this effluent concentration didn't satisfy the water quality grade I, II of river and lake. But as treated effluent of 1st reactor with 2nd reactor, we could achieve appropriate water quality, since instillation of 2nd reactor was needed. 2. Difference of media pore size between 1.5cm and 2cm didn't effect significantly to treatment efficiency and since this of 2nd reactor was about BOD 60%, COD 50%, an consideration of economic point of view should be carried out in field application. 3. Reaction order and substrate flux was varied 0.9851~0.9956 and 0.0028~0.0405 mg/$cm^{2} \cdot day$, and the substrate flux was increased as infiuent substrate concentration increased.

• KSBB Journal
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• v.14 no.4
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• pp.452-459
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• 1999

A two-stage continuous stirred tank reactor (CSTR)/trickling biofilter reactor (TBR) system was developed for the degradation of gas-phase trichloroethlene (TCE) using Methylosinus trichoporium OB3b. Mrthylosinus trichosporium OB3b was immobilized on activated carbons in TBR and the microbial growth reactor of a CSTR was coupled for the reactivation of the deactivated cells during TCE degradation. The effect of operation variables on TCE conversion and degradation rate were studied. At inlet TCE concentrations ranging from 10 to 80 $\mu$mol/L, TCE degradation rate was increased up to 525 mg TCE/Lㆍday with 75% conversion. The TCE degradation rates were also increased with increse in broth recycle flow rate, gas flow rate and dilution rate. When the temperature of TBR was changed from 3$0^{\circ}C$ to 15$^{\circ}C$, TCE degradation rate and TCE conversion were increased due to the enhanced TCE transfer from gas-phase. The two-stage reactor system was found to be stable and has been operated for more than 270 days.

• Journal of Life Science
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• v.13 no.6
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• pp.970-975
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• 2003

Microbial trichloroethylene (TCE) degradation using trickling biofilter (TBF) is a cost-effective treatment method, in which monooxygenase (MO) fortuitously transforms TCE via cometabolism. Simple TBF, however, could not be stably operated for long-term treatment of TCE due to the contradictory characteristics of cometabolism. In this paper, microbial biocatalyst and biofilm reactor system, a two-stage continuous stirred tank reactor (CSTR)/TBF system using Burkholderia cepacia G4 and Methylosinus trichosporium OB3b, are evaluated for the long-term continuous treatment of TCE. The maximum TCE elimination capacities were in the range of 28 and 525 mg TCE/1$.$day. The reactor systems were stably operated for more than 3∼12 months.

• Transactions of the Korean hydrogen and new energy society
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• v.17 no.1
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• pp.98-108
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• 2006

본 연구에서는 이 단계 연속 바이오 수소/메탄 생산공정의 경제성을 조사하였다. 경제적 관점에서 다양한 수소 및 메탄 발효용 생물반응기를 비교 평가하였다. 이를 바탕으로 포도당으로부터 일 단계 수소발효를 위해 고온 trickling biofilter 반응기 (TBR, $100\;m^3$ 규모)를, 일 단계 반응의 부산물로 생성된 유기산과 알콜류의 이 단계 메탄전환을 위해 고온 upflow anaerobic sludge 반응기 (UASB; $700\;m^3$ 규모)를 선정하였다. 본 이 단계 공정의 수소생산 비용은 $$\;0.26/Nm^3$으로 계산되었고, 이는 고온 TBR 반응기만을 이용한 경우보다 약 30 % 낮았다. 이 단계 공정의 낮은 수소생산 비용은 높은 에너지 회수율과 낮은 슬러지 처리비용에 의한 것이었다. 생물학적 수소 생산공정의 경제성은 탄소원의 종류, 생물반응기의 형태 등 여러 인자에 의해 변경될 수 있으나, 본 연구결과는 향후 연구를 위한 유용한 기준으로 고려될 수 있다.