• Applied Chemistry for Engineering
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• v.22 no.3
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• pp.296-300
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• 2011

In this work, various wood biomasses were used to determine the combustion characteristics for the fuel of cogeneration plant. Combustion characteristics of four types, i.e., (i) forest products, (ii) recycled wood, (iii) empty fruit bunch, and (iv) palm kernel shell, were examined via thermal gravimetric analyzer (TGA) in air atmosphere and coal was used as a comparison group. From the TGA results, the combustion of the wood biomass was occurred in the range of 280 to $420^{\circ}C$, which was lower than that of coal. Forest product showed the lowest activation energy (0.4 kJ/mol) compared to that of other wood biomasses (about 6 to 14 kJ/mol) and coal (64 kJ/mol). In addition, the reaction rate constant of the wood biomass was lower than that of coal. These results indicate the higher combustion initiation rate of wood biomass due to the high content of volatile matter, which had a low boiling point.

• Resources Recycling
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• v.23 no.2
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• pp.81-89
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• 2014

Approximately 8.5 million tons of fly ash and 740,000 tons of briquette ash were produced in 2010. Inefficient recycling of coal ash has been a heavy economic and environmental burden and economical coal ash utilization technologies are required to turn coal ash into valuable resources. In this study the patents and literature were analyzed to understand the present situation of coal ash recycling technologies and to promote utilization of coal ash for producing a non-sintering green cement, geopolymer. The survey was based on the open patents of USA, European Union, Japan and Korea, and the papers in SCI - indexed journals published between 1979 and 2013. Technical key words were used for data collection and noise filtering. Trends of recycling technologies in utilization of coal ash for producing geopolymers were discussed in terms of time periods, countries, companies and various forms of technologies.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2000.11a
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• pp.247-248
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• 2000

산업규모의 급속한 팽창과 더불어 에너지원의 확보에 석탄이 차지하는 비중이 커지고, 산업경제의 부산물인 쓰레기의 처리가 매립에서 소각방식으로 바뀌어가고 있는 시점에서 산업연료사용량과 난방부분의 에너지 사용량이 급속히 증가하고 있다. 이러한 인간의 생산활동으로 인해 대기 중으로 배출되는 가스는 크게 연소가스와 소각가스로 분리할 수 있는데 대표적인 연소가스로써는 SO$_2$가 있으며, 소각가스로는 HCl이 있다. (중략)

• Proceedings of the Korea Air Pollution Research Association Conference
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• 1999.10a
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• pp.451-452
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• 1999

석탄이나 석유와 같은 화석연료의 연소 시 대기 중에 발생되는 황산화물의 배출저감 방법으로서 사용연료의 황 함유량을 감소시키는 연소 전 처리방법과 연소과정 중 제거방법, 연소 후 제거하는 방법으로 구분할 수 있다. 본 논문에서는 전기 생산능력 40만 kW 급 중유화력 발전소의 연료 연소 후 배기가스 중 황 성분을 제거하는 방법으로 석회석 슬러리와 배기가스를 효과적으로 접촉시켜 SOx 와 먼지 등의 환경오염물질을 제거하고 부산물로 재활용 가능한 고순도의 석고를 생산하게 되는 JBR (Jet Bubbling Reactor) 형식의 습식 석회석-석고법 배연탈황 시스템을 소개하고자 한다.(중략)

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.2
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• pp.253-259
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• 2012

Disposal of high amount of coal combustion by-products, such as fly ash and bottom ash, is of a great concern to the country, due to the huge treatment cost and land requirement. On the other hand, those coal-ash wastes are considered to have desirable characteristics that may improve physical, chemical, and biological properties of soils. Especially, compared with fly ash, bottom ash has a larger particle size, porous surface area, and usable amount of micronutrients. In the present study, we examined bottom as a soil amendment for mitigating $CO_2$ emission and enhancing carbon sequestration in soils fertilized with organic matter (hairy vetch, green barely, and oil cake fertilizer). Through laboratory incubation, $CO_2$ released from the soil was quantitatively and periodically monitored with an enforced-aeration and high-temperature respirometer. We observed that amendment of bottom ash led to a marked reduction in $CO_2$ emission rate and cumulative amount of $CO_2$ released, which was generally proportional to the amount of bottom ash applied. We also found that the temporal patterns of $CO_2$ emission and C sequestration effects were partially dependent on the relative of proportion labile carbon and C/N ratio of the organic matter. Our results strongly suggest that amendment of bottom ash has potential benefits for fixing labile carbon as more stable soil organic matter, unless the bottom ash contains toxic levels of heavy metals or other contaminants.

• Journal of Energy Engineering
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• v.21 no.1
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• pp.68-74
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• 2012

Sub-bituminous coals have been used increasingly in coal-fired power plants with a proportion of over 50% in the blend with bituminous coals. As a result, the unburned material in fly ash has increased and is causing problems in utilizing the fly ash as an additive for concrete production. In this study, analysis of fly ash obtained from a 500 MWe power plant was carried out and unburned material in the fly ash found to be soot. The coals used in the plant were analyzed with CPD model to investigate the sooting potential depending on the coal type and blending ratio.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2000.04a
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• pp.371-372
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• 2000

국내 해안에는 양식업에서 부산물로 다량 발생되는 굴, 홍합, 대합 등의 패각들이 해안에 야적되어 연안어장의 오염, 공유수면 관리상의 지장, 자연경관의 훼손 및 보건 위생상의 문제 등으로 환경오염을 초래하고 있다(정종현 등, 1998). 현재 폐 패각의 총발생량은 355,000톤 정도이며, 이 중 종묘채묘용으로 재사용되는 양을 제외하면, 토지개량제로서의 이용 등을 포함한 재활용율은 약 30%정도로 낮은 실정이다. (굴수협전국조합, 1999). 더구나 처리비용이 비싸기 때문에 발생되는 폐 패각은 대부분 방치되고 있는 실정이다. (중략)

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 2003.05a
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• pp.509-512
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• 2003

폐기물을 대상으로 하는 가스화공정은 환경문제와 에너지효율 문제에 동시에 접근할 수 있는 공정으로서 기존의 연소반응에 근거한 공정들을 점차 대체할 것으로 예측되고 있으며 많은 연구와 기술개발이 현재 진행되고 있다. 가스화용융 기술의 장점은 고유황, 고회분의 저급 석탄, 정유공장 부산물 및 도시폐기물까지도 강화되는 환경규제치를 만족하면서 깨끗한 에너지원으로 활용할 수 있다는 점이며, 발생된 고열량 생성가스의 정제를 통해서 연료로서 재활용이 가능하다는 것이다.(중략)

• Resources Recycling
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• v.16 no.6
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• pp.28-33
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• 2007

Coal is the most abundant energy source and deposited in every area of world. Combustion process with lower efficiency has been mainly used. Therefore, implementation of more efficient technologies, involving gasification, combined cycles and fuel cells, would be a key issue in the plans for more efficient power generation. In these technologies, gasification has been studied for decades. However, coal gasification to high value combustible gas such as hydrogen and carbon monoxide is focused again due to high oil price. The gaseous product, called syngas, can be effectively utilized in a variety of ways ranging from electricity production to chemical industry (as feedstock). In this study, coal gasification with ultra high temperature steam has been performed. The effect of steam/carbon ratio on the produced gas concentrations, gasification rate and additional products like tar, ammonia and cyan compounds has been determined.

• Journal of the Korea institute for structural maintenance and inspection
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• v.17 no.3
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• pp.108-117
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• 2013

Among the byproducts from thermal power plant using coal combustion, fly ash as mineral admixture is widely utilized in concrete manufacturing for its engineering merits. However residuals including bottom ash are usually reclaimed. This study presents an evaluation of engineering properties in cement mortar with pond ash (PA). For this work, two types of pond ash (anthracite and bituminous coal) are selected from two reclamation sites. Cement mortar specimens considering two w/c (0.385 and 0.485) ratios and three replacement ratio of sand (0%, 30%, and 60%) are prepared and their workability, mechanical, and durability performance are evaluated. Anthracite pond ash has high absorption and smooth surface so that it shows reasonable workability, strength development, and durability performance since it has dense pore structure due to smooth surface and sufficient mixing water inside. Reuse of PA is expected to be feasible since PA cement mortar has reasonable engineering performance compared with normal cement mortar.