막분리와 저온 냉각분리를 이용한 혐기성 소화가스로부터 온실가스 회수저감 기술

황철원 ( Cheol-won Hwang ),정창훈 ( Chang-hun Jeong ) 한국환경기술학회 2013 한국환경기술학회지 Vol.14 No.3

혐기성 소화 작용에 의해 발생되는 바이오가스의 에너지원으로 사용은 온실가스 감축과 신재생에너지 보급 확대에 기여할 수 있다. 바이오가스의 에너지 함량은 직접적으로 메탄농도에 비례하며, 이산화탄소와 불순물 함량을 감소시킴으로써 고질가스로 이용이 가능하다. 본 연구에서는 환경 기초시설에서 발생되는 부생가스로부터 이산화탄소와 메탄 등의 온실가스를 회수하기 위한 혼성분리 공정(막분리+저온 냉각분리)을 개발하였다. 막분리 공정과 저온 냉각분리 공정의 성능평가 결과를 바탕으로 소화가스를 이용한 혼성분리 공정의 최적 운전시 메탄의 회수농도를 높이기 위해 1단계 분리막의 투과측을 감압하였으며, 메탄의 회수율을 높이기 위한 방법으로 2단계 분리막의 투과 가스와 저온 냉각분리 공정의 출구 가스를 1단계 분리막의 공급 유량으로 재순환시키는 방법을 사용하였다. 감압 및 재순환을 포함한 혼성분리 공정에서 메탄의 회수농도와 이산화탄소의 회수농도는 각각 94.3%와 99.5%였으며, 메탄의 회수율과 이산화탄소의 회수율은 각각 99.8%와 90.9%를 나타내었다. The potential of using the biogas as energy source is widely recognized. It is considered an important future contributor to the energy supply, although upgrading is needed. Biogas upgrading can be achieved after removing the CO₂ and contaminants. The main objective of the present research was CH₄ and CO₂ recovery from biogas generated in municipal wastewater treatment plant. Hybrid pilot plant(membrane + low-temperature separation process) for upgrading biogas was constructed and operated at a municipal wastewater treatment plant. The raw biogas contained 66 ~ 68 Vol % CH₄, the balance being mainly CO₂. The CH₄ concentration in the retentate stream was raised in field tests to 94.3 Vol % CH₄ and the CH₄ recovery efficiency was 99.8%. At the same time, the CO₂ recovery concentration and efficiency was 99.5% and 90.9%, respectively.

살충성곰팡이 Metarhizium anisopliae의 ura5 유전자의 분리동정

황철원,박인철,이동규,강선철 ( Cher Won Hwang,In Cheol Park,Dong Kyu Lee,Sun Cheol Kang ) 한국응용생명화학회 1997 Applied Biological Chemistry (Appl Biol Chem) Vol.40 No.1

About 250 by ura5 gene (Orotate phosphoribosyl transferase) fragment was cloned from genomic DNA of entomopathogenic fungus Metarhizium anisopliae by using PCR method. Entire nucleotide sequences of cloned DNA fragment were determined and analyzed as compared with other fungus ura5 genes. The amino acid sequence deduced from the nucleotide sequence showed 85.5% homology to ura5 protein of Trichoderma reesei. Using this 250 bp PCR fragment we have isolated full ura5 gene of M. anisopliae by genomic Southern hybridization and the isolated 4.4 kb DNA fragments were mapped by restrictional enzyme.

분리막을 이용한 혐기성 소화가스로부터 온실가스 회수저감 기술

황철원 ( Cheol Won Hwang ),정창훈 ( Chang Hun Jeong ) 한국환경과학회 2011 한국환경과학회지 Vol.20 No.10

The main objective of this experimental investigation was CH4 recovery from biogas generated in municipal and wastewater treatment plant. The polysulfone hollow fiber membrane was prepared in order to investigate the permeation properties of CH4 and CO2. Permeability of CO2 in Polysulfone membrane was 11-fold higher than of CH4 gas. A membrane pilot plant for upgrading biogas was constructed and operated at a municipal wastewater treatment plant. The raw biogas contained 66 ~ 68 Vol % CH4, the balance being mainly CO2. The effect of the operating pressure of feed and permeate side and feed flowrate on CH4 recovery concentration and efficiency were investigated with double stage membrane pilot plant. The CH4 concentration in the retentate stream was raised in these tests to 93 Vol % CH4.

촉매를 이용한 반도체 공정 SF6 처리에 관한 연구

황철원 ( Cheol Won Hwang ),최금찬 ( Kum Chan Choi ) 한국환경과학회 2013 한국환경과학회지 Vol.22 No.8

Sulfur hexa-fluoride has been used as a etching gas in semiconductor industry. From the globally environmental issues, it is urgent to control the emissions of this significant greenhouse gas. The main objective of this experimental investigation was to find the effective catalyst for SF6 decomposition. The precursor catalyst of hexa-aluminate was prepared to investigate the catalytic activity and stability. The precursor catalyst of hexa-aluminate was modified with Ni to enhance the catalytic activities and stability. The catalytic activity for SF6 decomposition increased by the addition of Ni and maximized at 6wt% addition of Ni. The addition of 6wt% Ni in precursor catalyst of hexa-aluminate improved the resistant to the HF and reduced the crystallization and phase transition of catalyst.

살충성곰팡이 Metarhizium anisopliae의 ura5 유전자의 분리동정

박인철,이동규,강선철,황철원,Park, In-Cheol,Lee, Dong-Kyu,Kang, Sun-Cheol,Hwang, Cher-Won 한국응용생명화학회 1997 Applied Biological Chemistry (Appl Biol Chem) Vol.43 No.1

환경친화형 생물농약개발을 위한 방안의 일환으로, 벼별구 등 농해충병원사상균 Metarhizium anisopliae의 분자생물학적 육종을 위해 영양요구성 돌연변이를 상보하는 선택유전자, ura5 (Orotate phosphoribosyl transferase)를 cloning하였다. Cloning방법으로는 기존에 알려진 사상균의 ura5 유전자들간에 확인된 상보성 염기배열을 합성하여, 이것을 primer로 사용하여 PCR기법에 의해 부분적으로 cloning하였다 또한, PCR기법에 의해cloning된 uras유전자단편의 염기배열을 결정한 결과, Trichoderma resei의 ura5유전자와는 아미노산수준에서 약 85%의 상동성을 나타내었으며, 이 단편을 이용하여 Metarhizium anisopliae의 genomic library로 부터 ura5유전자가 포함된 약 4.4 kb의 DNA단편을 cloning 하였다. About 250 bp ura5 gene (Orotate phosphoribosyl transferase) fragment was cloned from genomic DNA of entomopathogenic fungus Metarhizium anisopliae by using PCR method. Entire nucleotide sequences of cloned DNA fragment were determined and analysed as compared with other fungus ura5 genes. The amino acid sequence deduced from the nucleotide sequence showed 85.5% homology to ura5 protein of Trichoderma reesei. Using this 250 bp PCR fragment we have isolated full ura5 gene of M. anisopliae by genomic Southern hybridization and the isolated 4.4 kb DNA fragments were mapped by restrictional enzyme.

활동도를 이용한 2009년도 부산항 선박배출량 산정에 관한 연구

박두열 ( Doo Yeol Park ),황철원 ( Cheol Won Hwang ),정창훈 ( Chang Hun Jeong ),손장호 ( Zang Ho Shon ) 한국환경과학회 2011 한국환경과학회지 Vol.20 No.5

Emission of air pollutants such as nitrogen oxides (NOx), hydrocarbons (HC), SO2, and particulate matter (PM) and CO2 from ship during 2009 in Busan port was estimated based on activity-based method. The significant fraction (> 50%) of ship emission resulted from container and general cargo ships. Emission at port operation mode was the most dominant compared to at sea and maneuvering modes. Emission at North port was the largest source of air pollutants among ports. The magnitudes of air pollutants NO(x), SO2, HC, CO2, and PM in Busan port were 8.7×10(3), 8.23×10(3), 0.35×10(3), 4.86×10(6), and 0.67×10(3) ton/yr, respectively. The ratio of NOx to VOC is about 25. Our ship emission estimate is 2 times higher than that in CAPSS emission inventory.

Bacillus atrophaeus DYL-130이 생산하는 biosurfactant의 분리 및 특성

김선희,이상철,박인혜,유주순,주우홍,황철원,최용락,Kim Sun-Hee,Lee Sang-Cheol,Park In-Hye,Yoo Ju-Soon,Joo Woo-Hong,Hwang Cher-Won,Choi Young-Lark Korean Society of Life Science 2005 생명과학회지 Vol.15 No.5

원유 분해능이 강력한 균주를 얻고자 덕유산의 토양으로부터 crude oil을 탄소원으로 이용하는 수십 종을 분리하였다. 분리된 균주 중 원유분해능 및 biosurfactant 생성능이 우수한 균주를 선별하여, 형태학적 특성을 관찰하고 165 rDNA sequence와 』gyrA gene sequence를 통하여 Bacillus atrophaeus DYL-130으로 동정하였다. 동정된 균주 배양액의 표면장력은 최저 28 mN/m까지 감소되었다. 또한 Bacillus atrophaeus DYL-130이 생산하는 biosur-factant가 column chromatography에 의하여 분리 되었으며, 분리된 biosurfactant의 toluene 유화능 및 crude biosurfactant의 유화활성과 안정성이 시험 되었다. Crude biosurfactant의 유화활성은 kerosene에서 최대였으며, soybean oil에서도 높은 편이였으나 유화안정성의 경우 soybean oil을 기질로 하였을 경우가 kerosene을 기질로 하였을 때 보다 우수하였다. 또한 crude biosurfactant의 유화안정성을 합성계면활성제와 비교 한 결과 DYL-130이 생산하는 biosurfactant의 유화안정성이 합성계면활성제와 유사하거나 뛰어남을 확인하였다. Column chroma-tography에 의하여 분리된 biosurfactant는 drop-collapsing method에 의하여 surface-activity가 확인 되었으며 또한 toluene에 대한 유화력이 매우 뛰어난 것을 확인 하였다. 따라서 DYL-130에서 추출한 biosurfactant는 합성계면활성제를 대체할 수 있는 환경친화적인 생물 계면활성제로 사용될 수 있는 가능성을 보여주고 있다. 산업적으로 이 물질을 이용하기 위해서 Bacillus atrephaeus DYL-130이 생산하는 biosurfactant에 대한 구조분석과 물리 화학적 특성, 생분해도 및 환경독성 등의 조사를 수행하여야 할 것으로 생각된다. The objective of this study was investigate the characteristic of biosurfactant produced from the iso-lated strain. The strain was isolated from soli samples of Duck-Yu Mountain and it was identified as Bacillus atrophaeus DYL-130 by 16S rDNA and gyrA gene nucleotide sequence analysis. The surface ten-sion of culture filtrate of Bacillus atrophaeus DYL-130 decreased to 28 mN/m and its biosurfactant con-centration was determined by diluting the culture filtrate until the critical micelle concentration (CMC). The emulsifying activity and stability of crude biosurfactant was measured by using water-immiscible hydrocarbons and oils as substrate. The biosurfactant was purified by affinity chromatography and the surface activity of purified biosurfactant was measured by drop-collapsing method and it could be effectively emulsify toluene.