• Environmental Analysis Health and Toxicology
• /
• v.23 no.3
• /
• pp.171-178
• /
• 2008

수백여 종의 개별물질이 불완전 연소 혹은 유기물의 열분해로 인해 발생되는 다환방향족 탄화수소(PAHs)는 환경에서 중요한 오염원이 되고 있다. 본 연구는 다양한 바이오마커를 이용하여 수서생태계에 벤조피렌(benzo[a]pyrene)과 같은 다환방향족 탄화수소의 영향을 분석하였고, 이에 대한 통합적 결과 모델을 도출하였다. 즉, 잉어(Cyprinus carpio)를 이용하여 여러 농도의 벤조피렌(3, 12, $34{\mu}g/L$, 측정농도 기준)에 10일간 노출시킨 다음, DNA single-strand break, ethoxyresorufin-O-deethylase (EROD), acetylcholine esterase (AChE)와 vitellogenin (VTG)의 농도를 측정하였다. 벤조피렌은 잉어의 DNA 손상을 유도하였고, 낮은 농도에서 EROD와 VTC의 유의적인 활성을 보였으나, 신경전달물질과 관련이 깊은 AChE 효소활성에는 영향을 미치지 않았다. 이 결과를 star plot를 이용하여 통합 및 분석하였으며, 노출농도에 따른 통합 반응지수(integrated biomarker response value: IBR)로 나타내었다. 이런 다양한 바이오마커의 결과들은 벤조피렌에 대한 어류의 영향과 수생태 모니터링 자료로 이용 가능할 것으로 여겨지며, 통합반응지수는 생태위해성평가에서 유용한 도구로 쓰일 가치가 있는 것으로 평가된다.

• Journal of Hydrogen and New Energy
• /
• v.29 no.3
• /
• pp.280-291
• /
• 2018

Torrefaction is one of the methods to increase combustion calorific value and hydrophobicity of biomass. In this study, the effects of torrefaction on devolatilization, char reactivity and biomass structure were analyzed. Empty fruit bunch (EFB) and Kenaf biomass were used as fuels to be torrefied in the N2 environment at 200, 250 and $290^{\circ}C$. Devolatilization and char kinetics were analyzed by using TGA and biomass structure was investigated through petrography image. The reactivity showed different trends depending on the torrefaction temperature and biomass structure. The herbaceous biomass, Kenaf, was shown as high reactivity and thin wall structure. On the contrary, the woody biomass, EFB, had relatively low reactivity and thick wall structure.

• Journal of Wetlands Research
• /
• v.23 no.1
• /
• pp.54-59
• /
• 2021

DIWS system was introduced to remove hydrogen sulfide from the biogas of wastewater treatment plant. In the case of using water into the DIWS system more than 5,000mg/L of hydrogen sulfide, 25% of H2S removal efficiency was shown and required such further treatment process as incineration which was obtained more than 98%. When the inflow of hydrogen sulfide was 5,000mg/L, CH4 and CO2 were effectively discharged and the reduction was 8.7% and 28.6%, respectively. When such neutralization chemicals as Na2CO3 and NaOH were introduced into the DIWS system, H2S was removed more than 97.2% keeping pH in the range of 11.2 to 11.5.

• Journal of Hydrogen and New Energy
• /
• v.24 no.3
• /
• pp.249-254
• /
• 2013

The integrated gasification combined cycle (IGCC) system is well known for its high efficiency compared with other coal fueled power generation system. The aim of this study is to confirm the feasibility of using bio gas in coal feeding system and syngas recirculation system. The effects of using bio gas in the gasifier on the syngas composition were investigated through simulations using the Aspen Plus process simulator. It was found that these changes had an influence on the syngas composition of the final stream and bio gas can be used in a gasifier system.

• Journal of Hydrogen and New Energy
• /
• v.20 no.1
• /
• pp.55-63
• /
• 2009

In this study, thermochemical degradation by acetone solvolysis reaction of siberian spruce wood was investigated for a temperature range of $200{\sim}400^{\circ}C$. The liquid products by acetone solvolysis from siberian spruce wood produced various kinds of aliphatics, cyclic compounds and aromatics included phenols etc. Combustion heating value of liquid products by acetone solvolysis conversion processes was in the range of $8,010{\sim}8,180cal/g$. The energy yield in acetone solvolysis of siberian spruce wood was as high as 74.2% after 40min of reaction at $400^{\circ}C$. The liquid products from the thermochemical conversion of siberian spruce wood could be used as high-octane-value fuels and fuel additives.

• Journal of Hydrogen and New Energy
• /
• v.28 no.6
• /
• pp.697-703
• /
• 2017

This study investigated the high-efficient process for bioethanol from barley by various condition. First, higher concentrations of ethanol could be produced without loss of yield by using reducing water consumption. This is because it could prevent to increase viscosity despite reducing water consumption. Second, the ethanol yield could be improved by using reducing particle size of biomass (increase of enzyme reactive surface). Third, The addition of protease could have a considerable effect on yield of fermentation, which provides nutrients to the yeast. This results showed that bioethanol production would provide efficient ethanol production and lower production costs.

• Journal of Hydrogen and New Energy
• /
• v.19 no.5
• /
• pp.430-438
• /
• 2008

Siberian spruce, found in the northern temperature and boreal regions of the earth, is usable biomass as fuels. In this study, parameters of thermochemical degradation by pyrolysis-liquefaction reaction of siberian spruce such as the effect of reaction temperature, reaction time and degradation products and energy yields were investigated. The liquid products from pyrolysis-liquefaction of siberian spruce contained various kinds of cyclicketones, cresols, dimethyl phenols and benzenediols. Combustion heating value of liquid products from pyrolysis-liquefaction conversion processes was in the range of $7,650{\sim}7,800cal/g$. The energy yield in pyrolysis-liquefaction of siberian spruce was as high as 69.5% after 40min of reaction at $400^{\circ}C$. The liquid products from the thermochemical conversion of siberian spruce could be used as high octane value fuels and fuel additives.

• Journal of Hydrogen and New Energy
• /
• v.31 no.2
• /
• pp.223-233
• /
• 2020

Fast pyrolysis is one of the most promising technologies for converting biomass to liquid fuels. Pyrolysis bio-oil can replace petroleum-based fuels used in various thermal conversion devices. However, pyrolysis bio-oil is completely different from petroleum fuels. Therefore, in order to successfully use pyrolysis bio-oil, it is necessary to understand the fuel characteristics of pyrolysis bio-oil. This paper focuses on fuel characteristics and upgrading methods of pyrolysis bio-oil and discusses how these fuel characteristics can be applied to the use of pyrolysis bio-oils. In addition, the fuel quality standards of fast pyrolysis bio-oil were examined.

• Journal of Hydrogen and New Energy
• /
• v.32 no.6
• /
• pp.618-635
• /
• 2021

Environmental issues caused by our dependence on fossil fuels have caused our society to move toward new renewable sources of energy and chemicals. In this study, we develop an integrated process that co-produces butene oligomer (i.e., biofuels) and 1,3-butadiene (i.e., monomer for the production of synthetic rubber). To minimize utility consumption, we conduct heat integration. Then, we conduct a range of techno-economic analysis and life-cycle assessment to investigate economic and environmental feasibility of the proposed process.

• 한국신재생에너지학회:학술대회논문집
• /
• 2011.11a
• /
• pp.116-116
• /
• 2011

바이오 가스 플랜트의 혐기소화 공정에서 발생하는 바이오 가스는 중 유해가스인 황하수소($H_2S$)는 부식성 가스로 수천 PPM농도를 함유하여, 발전기나 가스보일러로 이용하는 경우에는 $H_2S$를 제거하는 탈황공정이 반드시 필요하다. 탈황방식에는 산화철 탈황(건식 탈황)과 생물 탈황이 현재 많이 사용되고 있어나 산화철 탈황은 산화철 pellet이 유화철에 변화하면 탈황능력이 저하되어 pellet을 교환해야 하며 많은 비용이 발생한다. 생물 탈황 방식은 유황산화세균의 서식활동조건(온도, 반응시간, 산소량)확보가 반드시 필요하여 높은 운전기술을 필요로 한다. 본 연구에서는 바이오가스 전처리 기술 중 활성탄 또는 약액을 이용한 기존의 탈황정제방식보다 흡착성능이 뛰어난 이온교환섬유를 이용하여, 황화수소($H_2S$)를 95% 이상 제거할 수 있는 고효율 섬유상 이온촉매 악취제거 시스템 개발을 수행하였다. 이온교환섬유는 방사선 조사를 이용하여 부직포에 라디칼을 인위적으로 형성시켜(그라프트 중합) 양이온 또는 양이온을 교환할 수 있도록 제조된 섬유상의 흡착제로, 이온교환 섬유의 화학적 이온교환과 물리적 흡착 및 탈착반응이 동시에 발생되고, 활성탄/실리카켈 보다 흡착능력이 2~4배 높다. 또한 이온섬유의 재생기능을 이용하여 장기적 다양한 악취($H_2S$, $NH_3$, 아민계, 메르갑탄류, 알데히드 등) 및 유해가스(VOCs, NOx, SOx) 등을 95% 이상 제거할 수 있다.