• Journal of Soil and Groundwater Environment
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• v.21 no.5
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• pp.1-7
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• 2016

The removal of non-aqueous phase liquids (NAPLs) from groundwater using pure water, via pump and treat, is quite ineffective due to their low solubility and hydrophobicity. Therefore, the objectives of pilot tests were to select potentially suitable surfactants that solubilize tetrachloroethylene (PCE) and trichloroethylene (TCE) present as contaminants and to evaluate the optimal range of process parameters that can increase the removal efficiency in surfactant-enhanced soil flushing (SESF). Used experimental method for surfactant selection was batch experiments. The surfactant solution parameters for SESF pilot tests were surfactant solution concentration, surfactant solution pH, and the flow rate of surfactant solution in the SESF pilot system. Based on the batch experiments for surfactant selection, DOSL (an anionic surfactant) was selected as a suitable surfactant that solubilizes PCE and TCE present as contaminants. The highest recovery (95%) of the contaminants was obtained using a DOSL surfactant in the batch experiments. The pilot test results revealed that the optimum conditions were achieved with a surfactant solution concentration of 4% (v/v), a surfactant solution pH of 7.5, and a flow rate of 30 L/min of surfactant solution (Lee and Woo, 2015). The maximum removal of contaminants (89%) was obtained when optimum conditions were simultaneously met in pilot-scale SESF operations. These results confirm the viability of SESF for treating PCE and TCE-contaminated groundwater.

• KSBB Journal
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• v.30 no.6
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• pp.345-349
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• 2015

Antifreeze proteins (AFP) inhibit growth and recrystallization of ice, and permit organisms to survive in cold environments. The AFP from an Antarctic bacterium, Flavobacterium frigoris PS1, FfIBP (Flavobacterium frigoris icebinding protein), was produced in E. coli using a cold shock induction system. The culture temperature was shifted from $37^{\circ}C$ to $15^{\circ}C$ and a 20 L culture scale was used. The final weights of dried cell and FfIBP were estimated to be 126 g and 8.4 g, respectively. The thermal hysteresis (TH) activity ($1.53^{\circ}C$) of the produced FfIBP was 3.6-fold higher than that of the LeIBP (Leucosporidium ice-binding protein) produced in Picha. The current study demonstrates that large-scale production of FfIBP was successful and the result could be extended to further application studies using recombinant AFPs.

• Journal of the Korean GEO-environmental Society
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• v.11 no.8
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• pp.41-47
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• 2010

This study was conducted to assess the applicability of pilot scale system and to evaluate the treatment efficiency on operational parameters such as humic acid concentration, initial pH and air flow rate on the ozone/peroxyl radical reaction system. The decolorization of ozone/peroxyl radical system was higher than that of only process. Removal efficiency of ozone/peroxyl radical system was generally increased with the increase of intial concentration of humic acid but decreased over the range of 30mg/L. Treatment efficiency of HA at acid pH was smaller compared to that of neutral or basic pH and increased with increasing the air flow rate from 1L/min to 3L/min. In pilot-scale test, average removal of TOC and $COD_{Cr}$ was about 70% and 60%, respectively and ozone/peroxyl radical reaction system was indicated a potential in water treatment application.

• Microbiology and Biotechnology Letters
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• v.32 no.3
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• pp.243-248
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• 2004

Production of (R)-3-hydroxybutyric acid (R3HB) by fed-batch culture and continuous culture of metabolically engineered Escherichia coli harboring Ralstonia eutropha PHB biosynthesis and depolymerase genes was examined in a 30 1 pilot-scale fermentor. A new stable two-plasmid system, pBRRed containing the R. eutropha PHB depolymerase gene and pMCS 105 containing the R. eutropha PHB biosynthesis genes, was developed. Among a variety of E. coli strains harboring plasmids, recombinant E. coli XL-10 Gold (pBRRed, pMCS105) was able to produce R3HB with the highest efficiency in a batch culture. By the fed-batch culture of recombinant E. coli XL-10 Gold(pBRRed, pMCS 105) in a 30 1 fer-mentor, the final R3HB concentration was 22.4 g/l giving a productivity of 0.97 g/l-h. To produce R3HB to a high concentration with high productivity, a new strategy of fed-batch culture followed by a continuous culture was investigated. The maximum productivity and R3HB concentration were 5.06 g/l-h and 25.3 g/l, respectively. These results show that economical production of R3HB is possible by recombinant E. coli in large scale.

• Journal of Environmental Science International
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• v.23 no.4
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• pp.681-695
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• 2014

In a pilot-scale dyeing wastewater treatment using two-type fluidizing media, each thickness of biofilm was 15 and 30 ${\mu}m$, respectively. The numbers of protozoa inhabited in small-size (PEMT A) and big-size (PEMT B) media were $7.5{\times}10^4$ and $1.25{\times}10^5$ cells/ml, respectively, and dominant species were Entosiphon sulcatus var sulcatus in PEMT A and Chlamydomonas reinhardtii in PEMT B, respectively. Flask experiments using the two media revealed that the percentages of color removal were 25.8% in PEMT A and 27.1% in PEMT B after 72-h cultivation, indicating the necessity of bioaugmentation. Experiments for bioaugmentation effect on color removal were carried out in the pilot-scale treatment for 75 d by three-step operation under the control of wastewater loading rate and microbial input rate. Dye degradation occurred mainly in the second reaction tank, and the attachment of augmented dye-degrading microorganisms to media took at least 35 d. Final value of chromaticity in effluent was 227, meeting the required standard. Therefore bioaugmentation onto media was good for color treatment. In summary, thickness of biofilm formed on the media depended upon the size of media, resulting in different ecosystem inside the media. Hence, this affected microbial community and color treatment further. Accordingly, the reduction of operation cost is expected by efficient color-treatment process using bioaugmented media.

• Membrane Journal
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• v.18 no.2
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• pp.109-115
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• 2008

To remove total dissolved solid (TDS) from wastewater, a carbon membrane system was prepared, using carbon membranes made from conductive activated carbon and poly(vinylidene fluoride) (PVDF). Using 100 ppm aqueous solutions of NaCl, $Na_2SO_4,\;MgCl_2,\;MgSO_4$, the basic properties of the carbon membranes used were studied. For the treatment of the real dye wastewater supplied from Kyungin Corp., a pilot scale carbon membrane system was also prepared, which was consisted of 240 plies of carbon membranes of $20cm{\times}20cm$ (length${\times}$width). Using the real wastewater with different TDS such as 941, 2050, 2810, 3830, 4960, 6030 ppm, prepared by the dilution of the original wastewater with pure water, the performance of the pilot scale carbon membrane system was studied. The effect of the operational conditions was studied.

• Journal of the Korean Society of Combustion
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• v.16 no.3
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• pp.12-20
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• 2011

Oxy-coal combustion for $CO_2$ capture in coal power plants entails a mode switching from air-firing to oxyfiring. In this study, procedure of the mode switching was investigated and discussed through experiments in pilot scale facilities: (1) a 0.3 $MW_{th}$ furnace with a vertical single burner and a FGR(Flue Gas Recirculation) system (2) a 1 $MW_{th}$ furnace with horizontal 4 burners and a FGR system. Principle of the mode switching was established and performed with control of FD fan, FGR fan, ID fan and oxygen flow rates. We have found that equivalence ratio in the oxy-firing mode should be increased more than that in the air-firing to achieve stable mode switching. Control of FD, ID and FGR fans should be performed carefully in the mode switching, in the sense of complete combustion and flame attachment. Moisture contents in the ash and the flue gas recycled to the primary oxidizer stream should be removed to prevent condensation, corrosion and duct clogging.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 2004.05a
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• pp.109-114
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• 2004

• Nuclear Engineering and Technology
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• v.49 no.7
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• pp.1451-1456
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• 2017

Finding technical issues associated with equipment scale-up is an important subject for the investigation of pyroprocessing. In this respect, electrolytic reduction of 1 kg $UO_2$, a unit process of pyroprocessing, was conducted using graphite as an anode material to figure out the scale-up issues of the C anode-based system at pilot scale. The graphite anode can transfer a current that is 6-7 times higher than that of a conventional Pt anode with the same reactor, showing the superiority of the graphite anode. $UO_2$ pellets were turned into metallic U during the reaction. However, several problems were discovered after the experiments, such as reaction instability by reduced effective anode area (induced by the existence of $Cl_2$ around anode and anode consumption), relatively low metal conversion rate, and corrosion of the reactor. These issues should be overcome for the scale-up of the electrolytic reducer using the C anode.

• Environmental engineer
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• s.181
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• pp.70-75
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• 2001

본 연구는 '99년 7월에 벤처형 중소기업 기술개발 지원사업으로 신규 계약된 과제로서 상수원수의 전처리 및 하수 2차 침전수의 재처리 공정에 활용될 생물 산화 여과지를 개발하는 것이다. 생물 산화 여과 system은 상수 원수의 전처리, 상수도의 고도정수 처리, 하수 및 폐수처리에 이용될 수 있는 것으로, 특히 물리적 여과기능과 포기 과정을 통한 산화 기능을 포함하는 생물학적 분해 및 자연정화처리환경을 유지하여 수질이 악화된 상수도의 전·후처리나 하.폐수의 3차 처리에 적용하기 위한 것이다. 생물 산화 여과 시스템은 여과지의 하부 장치에 균등한 공기(산소)공급시설을 하여 여과층에 연속적으로 공기를 공급하면서 여과를 함으로서 생물막 여과 및 산화 기능으로 유기물질, 철, 망간 등을 제거하고 공기의 부상력에 의하여 조류, 부유물질, 냄새 등을 동시에 제거하는 System이다. 현재 상수처리 공정으로서의 생물 산화 여과지 개발을 위해 Bench-scale과 semi-pilot plant를 거쳐 Y시 M취수장애 pilot plant를 설치하여 연구를 진행중에 있으며, 또한, G시 G하수처리장에 하수처리 공정에 관한 연구를 위해 pilot plant를 설치하고 하수 3차 처리와 저농도 하·폐수 처리를 중심으로 연구중에 있다. 아래의 연구 결과는 정수처리 공정 연구를 위한 Bench-scale plant실험을 통해 얻은 결과치이며 현재까지 진행된 연구는 주로 정수처리 공정 중심으로 이루어 졌으나 pilot plant에서는 정수 및 하수처리에서의 생물산화여과공정의 연구가 진행중이다. 현재 연구가 진행중이므로 각 인자별 최적운전조건 등은 계속적인 실험과 연구를 통해 찾아지겠으나 현재까지 수행된 연구자료를 기반으로 볼 때 생물산화 여과장치는 탁도, SS, VSS 등의 제거에 탁월한 효능을 보이고 있다. 수처리용 장치로서의 이러한 기본적인 기능 이외에 NPOC, DOC 제거에도 뛰어난 효능을 보이고 있으며 특히 정수처리 공정에서 문제시 되고 있는 동절기 암모니아성 질소제거 또한 큰 가능성을 보여주고 있다. 그 동안 외국기술에 전면 의존해 오던 생물 산화 여과방식의 국내개발은 비용 절감뿐만 아니라 국내 실정에 맞는 기술개발이라는 점에서 향후 그 적용 범위를 넓혀 갈 수 있을 것이다.