• 에너지공학
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• 제29권3호
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• pp.57-63
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• 2020

In this paper, we reported that the global trend of cement production and utilization as raw materials and as a fuel. As we know, cement is one of the significant materials required for the construction industry. The recent trend of rising urbanization, both the cement and construction industry played a vital role. The cement industry is a major sustainable infrastructure for the countries. Currently, China producing cement half of the world's cement production. During the year 2018, Korea producing cements nearly 57.5 million metric tons. Waste materials are used as circular resources and also having tremendous benefits for cement production. Another important use of these circular resources is fuel for the cement industry. There is a large potential benefit of the cement industry, but it's creating a severe environmental threat. The cement industry contributes to the major emissions of CO2. This leads the global warming. As per the Paris agreement, the Korean government initiated the recycling policy of waste materials and also the utilization of circular resources for the prevention of limited natural resources and also the global warming effect.

• 신재생에너지
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• 제18권3호
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• pp.10-22
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• 2022

Forest biomass energy is based on scientific evidence in response to carbon neutrality and the climate crisis, international consensus, and environmental-geographic characteristics of each nation. In this study, the authors aimed to analyze macroscopic forest biomass energy policies for ten major countries. They categorized them into six detailed categories (Sustainable utilization, Cascading Uutilization, Replacement of fossil fuel/Carbon intensive products, Utilization of forest by-products/residues as the source of energy, Contribution to carbon-neutral/climate change, and Biomass combined with CCS/CCUS ). In addition, the surveyed nations have developed a policy consensus on the active use of forest biomass with sustainable forest management except for the cascading utilization category. Furthermore, the authors evaluated the mid to long-term plans of the Korean government for improvements in the policy and legal aspects. As a result, the authors derived four major directions that South Korea should approach strategically in the future (1) secure financial resources for sustainable forest management and stimulating investment in the timber industry, (2) promote unified policies to establish a bio-economy, (3) enhancement of the forest biomass energy system, and (4) reorganization and promotion of strategy centered on the opinions of field experts in internal and external instability.

• 청정기술
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• 제18권3호
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• pp.229-249
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• 2012

산업 발달로 화석 연료 사용이 급증하고 이에 따른 지구 온난화 문제와 자원 고갈 문제가 대두되어 지속 성장을 위협하고 있다. 따라서 지속 성장을 위해서 두 문제를 모두 해결하여야 한다. 현재 이산화탄소의 처리 방법으로 인식되고 있는 이산화탄소 포집 및 저장 기술(carbon capture and sequestration, CCS)의 환경 논란으로 인해 사후 처리 기술의 필요성이 커지고 있다. 이에 해결책중 하나로 부각되고 있는 이산화탄소 포집 및 재활용 기술(carbon capture and utilization, CCU)에 대해서 알아보았다. 이산화탄소 전환 기술은 이산화탄소 배출량 감소에 따른 지구 온난화 문제의 해결 뿐 아니라 탄소원의 재활용이란 측면에서 자원고갈 문제의 해결책으로 제시될 수 있겠다. 이산화탄소 전환 기술은 기상 전환과 액상 전환으로 나눌 수 있으며 기상 전환의 경우 필요 에너지 공급원과 온화한 반응조건에서 전환이 이뤄져야 하고 저에너지 소비 생성물 분리 정제 기술의 개발이 필요하다. 액상 전환의 경우, 반응 속도를 높일 수 있는 촉매 및 광감응제 개발과 함께 촉매, 빛, 전기의 혼성 시스템의 개발이 요구되어진다. 이산화탄소 전환 기술은 신재생 에너지 및 바이오산업의 경쟁력 향상을 위한 연결 기술로 그 가치가 매우 크다.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2023년도 가을학술발표대회논문집
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• pp.93-94
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• 2023

This study evaluated the mechanical properties and microstructure of calcium silicate cement based paste according to carbonation curing conditions. As a result, both compressive strength and carbonation depth increased with the carbonation curing period.

• 한국환경보건학회지
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• 제27권4호
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• pp.79-83
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• 2001

The sludge wastes fermentation process reactors were operated to produce the VFAs(volatile fatty acids) as supplemental carbon sources and to determine the optimum operating conditions. The experiment was carried out by varied mixture ration of 400:0 350:30 300:100 200:200 and operating temperature 2$0^{\circ}C$ 3$0^{\circ}C$ and 4$0^{\circ}C$ The results were as follows: Higher VFAs production rate observed at higher mixed ratio of primary sludge. When the mixed ratio of primary sludge and return sludge were 400:0 350:50 300:100 200:200 respectively. VFAs production are were 829.6mg/l 944.2 mg/l 597.9mg/ml an d441.6 mg/l , respectively. the yield of VFAs increased with temperature, but decreased with initial TSS concentration Because fermented sludge has relatively low nitrogen and phosphorus and relatively high VFAs it can be used as a substitute for external carbon in biological nutrient removal process.

• Corrosion Science and Technology
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• 제5권1호
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• pp.23-26
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• 2006

Recent development of ultrafine grained (UFG) low carbon steels by using equal channel angular pressing (ECAP) and their room temperature tensile properties are reviewed, focusing on the strategies overcoming their inherent mechanical drawbacks. In addition to ferrite grain refinement, when proper post heat treatments are imposed, carbon atom dissolution from pearlitic cementite during ECAP can be utilized for microstructural modification such as uniform distribution of nano-sized cementite particles or microalloying element carbides inside UFG ferrite grains and fabrication of UFG ferrite/martensite dual phase steel. The utilization of nano-sized particles is effective on improving thermal stability of UFG low carbon ferrite/pearlite steel but less effective on improving its tensile properties. By contrast, UFG ferrite/martensite dual phase steel exhibits an excellent combination of ultrahigh strength, large uniform elongation and extensive strain hardenability.

• Advanced Composite Materials
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• 제16권2호
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• pp.135-149
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• 2007

In the automobile industry, structural health monitoring of fiber reinforced polymer composite parts is a widespread need for maintenance before breakdown of the functional elements or a complete vehicle. High performance sensors are generally used in many of the structural health monitoring operations. Within this study, a carbon fiber sewing thread has been used as a low cost laminate failure sensing element. The experimentation plan was set up according to the electrical conductance and flexibility of carbon fiber threads, advantages of preforming operations, and sewing mechanisms. The influence of the single thread damages by changing the electrical resistance and monitoring the impact location by using carbon thread sensors has been performed. Innovative utilization of relatively cost-effective carbon threads for monitoring the delamination of metallic inserts from the basic composite laminate structure is a highlighting feature of this study.

• The Plant Pathology Journal
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• 제24권1호
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• pp.58-62
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• 2008

Utilization of carbon sources by Bacillus cereus D324, a biological control agent, and Pythium species, which causes rice seedling disease, was studied with the objective of increasing the efficacy of biological control by providing the biological control agent with specific beneficial carbon sources. D-galactose, D-sorbitol, and D-mannitol were poor carbon sources for Pythium spp. growth but were good for B. cereus D324 growth. Growth in a growth chamber of rice seeds coated with B. cereus D324 amended with specific carbon sources, such as D-galactose and D-sorbitol, showed significantly enhanced seedling emergence compared to seeds coated only with B. cereus D324. Field trials showed that both seedling emergence and yield increased, when the above specific carbon sources were added to B. cereus D324 in seed coating formulations. This result indicated that amending seed coating formulations with specific carbon sources could significantly increase seedling emergence and yield in the field.

• Asian-Australasian Journal of Animal Sciences
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• 제12권7호
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• pp.1080-1084
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• 1999

Carbon (C) and nitrogen (N) balance technique was used to determine energy balance in Rhode Island Red (RIR) and White Leghorn (WL) laying hens fed maize-and broken rice (BR)- based diets. Carbon and nitrogen intake and outgo were determined for three days on ad libitum fed diets followed by 2/3 of ad libitum intake for next three days. Carbon analysis was done by using four 'U' tubes in which carbon dioxide released during bomb calorimetry was absorbed on drierite in tube 1 and 2 whereas tube 3 and 4 contained sodalime self indicating granule. Carbon in $CO_2$ was determined by an open circuit respiration system. Energy retention (E, kcal) was calculated as E = 12.386 C (g) - 4.631 N (g). By regressing metabolisable energy (ME) intake on energy balance, maintenance ME requirement of RIR was 128 whereas, that of WL hens was $144kcal/kg\;W^{0.75}/d$. Effciency of utilization of ME for maintenance from BR-based diet in RIR hens was equal but in WL hens it was 11% less than maize-based diet.

• Bulletin of the Korean Chemical Society
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• 제34권5호
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• pp.1435-1440
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• 2013

To investigate the influence of the carbon matrix on the electrochemical performance of Si/C composites, four types of Si/C composites were prepared using graphite, petroleum coke, pitch and sucrose as carbon precursors. A ball mill was used to prepare Si/C blends from graphite and petroleum coke, whereas a dispersion technique was used to fabricate Si/C composites where Si was embedded in disordered carbon matrix derived from pitch or sucrose. The Si/pitch-based carbon composite showed superior Si utilization (96% in the first cycle) and excellent cycle retention (70% after 40 cycles), which was attributed to the effective encapsulation of Si and the buffering effect of the surrounding carbon matrix on the silicon particles.