• 대한기계학회논문집B
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• 제33권8호
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• pp.613-621
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• 2009

Coal is the energy resource which is important with the new remarking energy resource. Coal combustion produces more NOx per unit of energy than any other major combustion technology. Pollutant emission associated with coal combustion will have a huge impact on the environment. Coal conversion has three processes which are drying, coal devolatilization and char oxidation. Coal devolatilization process is important because it has been shown that HCN which is converted from volatile N contributes 60 to 80% of the total NOx produced. This paper addresses mass release behavior of char, tar, gas and HCN in an experiment of Laminar Flow Reactor with two coals such as Roto middle coal (Sub-bituminous) and Anglo coal (Bituminous). The experiment is compared with the data predicted by CPD model for mass release of HCN about Roto south, Indominco, Weris creek and China orch coals. The results show that HCN increases as a function of decreasing the ratio of fixed carbon(FC)/ volatile matter(VM of the coals contain.)

• 한국연소학회:학술대회논문집
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• 한국연소학회 2012년도 제44회 KOSCO SYMPOSIUM 초록집
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• pp.209-212
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• 2012

This study was performed to analyze coal flames and measure tar and soot yields and structures of chars for two coals depending on the volatile content by the LFR(Laminar Flow Reactor) which can be applied to a variety of coal researches. The results show that volatile contents and oxygen concentration have significant influence on length and width of the soot cloud and it also indicate that the length and width of the cloud in condition of combustion decrease than those of pyrolysis atmosphere. Until the sampling height reach at 50 mm, the tar and soot yields of Berau (Sub-bituminous) coal contained relatively lots of volatile matters are less than those of Glencore A.P. (Bituminous) coal. On the other hand, tar and soot yields of Berau coal are higher than those of Glencore A.P. coal by reacted residual volatile matter. In addition, the images of samples obtained from the particle separation system of the sampling probe support for above results with the yields, and the pore development of char surface by devolatilization.

• 청정기술
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• 제21권1호
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• pp.53-61
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• 2015

본 연구는 인도네시아 아역청탄인 키데코(Kideco)탄의 촤(char)-이산화탄소 촉매가스화 kinetic분석을 열중량분석기(thermogravimetric analysis, TGA)를 이용하여 수행하였다. 촉매는 탄산칼륨 및 탄산나트륨을 선정하였으며, 석탄과 촉매의 물리적 혼합을 통하여 촤를 제조하였다. 촤-이산화탄소 촉매가스화반응은 탄산나트륨 7 wt%, 850 ℃에서 이산화탄소 농도가 60 vol%일 때 가장 빠른 탄소전환율을 보여주었다. 750~900 ℃ 등온조건에서 촤-이산화탄소 촉매가스화 반응결과, 온도가 증가할수록 탄소전환율 속도가 빨라졌으며, 기-고체 반응모델 shrinking core model (SCM), random pore model (RPM), volumetric reaction model (VRM) 및 modified volumetric reaction model (MVRM)을 실험결과에 적용하였을 때, MVRM이 키데코탄의 가스화반응 거동을 잘 예측하였다. 또한 Arrhenius plot을 통한 활성화에너지는 탄산나트륨을 첨가한 촤가 탄산 칼륨을 첨가한 촤보다 더 우수한 촉매 활성을 보여주었다.

• 대한기계학회논문집B
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• 제23권11호
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• pp.1464-1472
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• 1999

Design and operation of $1MW_{th}$ pulverized coal combustion testing facility are described. Also the influence of air staging on NOx emission and burnout of coal flames was investigated in this facility. The test facility consisted of coal feeding system, firing system and flue gas treatment system. A top-fired externally air staging burner was adopted in order to avoid influence of gravity on the coal particles and for easy maintenance. Distribution of temperature and chemical species concentration of coal flames could be measured in vertical pass of furnace. Main fuel was pulverized (83.4% less than $80{\mu}m$) Australian high bituminous coal. From variety of test conditions, overall excess air ratio was selected at 1.2(20% excess air). Tho study showed that increasing the staged air resulted in lower NOx omission, and it was suggested to be more than 40% of the total combustion air for the substantial NOx reduction. Sufficient burnout was not achievable when NOx emission was less than 500ppm. Also, the amount of core air did not influence tho NOx reduction.

• 플랜트 저널
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• 제7권2호
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• pp.44-51
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• 2011

Given the fact that the entire bituminous coal used for a boiler is imported, the supply of coal is often affected by the rise of international coal price. Moreover, coal suppliers have been diversified due to the competition among power generation companies for reducing costs and inexpensive sub-bituminous coal is used. As a result, boilers combustion conditions have been deviated from the initial boiler design. This requires the selection of adequate excessive air ratio for different combustion conditions to enhance the efficiency of boiler operation. The boiler efficiency has been identified through an examination on the change of excessive air ratio by mixed fuel in unit 8 of Dangjin power plant complex. In addition, an excessive air ratio was calculated based on the examination result. According to the study result, the adequate excessive air ratio was 13% when Macquarie and Powder river were mixed at a ratio of 5:5 and when Sonoma and Megaprima persada were mixed at a ratio of 5:5. When BHP Billiton and Powder river were mixed at a ratio of 4:6 and Centennial and Batubara were mixed at a ratio of 3:7, the adequate excessive air ratio was 11%.

• 한국에너지공학회:학술대회논문집
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• 한국에너지공학회 1999년도 춘계 학술발표회 논문집
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• pp.39-44
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• 1999

발전용 연료로 사용하는 석탄은 취급의 어려움과 가스 및 석유에 비해 품질이 낮은 단점이 있으나, 매장량이 풍부하고 가격이 저렴하여 발전용 연료로의 사용은 더욱 증대될 전망이다. 이에 따라 석탄의 안정적 수급 측면에서 구입원의 다양화가 예상되고 있으나, 현재 발전용 연료의 연소특성 평가는 주로 실험실적 기초 시험에 의존함에 따라 정확한 평가가 곤란한 실정이므로 시험연소로를 이용하여 각종 연소특성을 비교 평가하여 탄종별 최적 연소조건 규명과 적정 흔탄비에 대한 Data Base를 구축하고자 한다.(중략)

• 환경영향평가
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• 제16권4호
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• pp.277-283
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• 2007

Since the Kyoto Protocol became into effect, Korea has been expected to be part of the Annex I countries performing the duty of GHG reduction in the phase of post-Kyoto. Therefore, it is necessary to develop emission factors appropriate to Korean circumstances. In order to develop emission factors this study utilized the CleanSYS, which is the real-time monitoring system for industrial smoke stacks to calculate the emission rate of $CO_2$ continuously. In this study, the main focus was on the power generation plants emitting the largest amount of $CO_2$ among the sectors of fossil fuel combustion. Also, an examination on the comparison of $CO_2$ emission was made among 3 generation plants using the different types of fuels such as bituminous coal and LNG; one for coal and others for LNG. The $CO_2$ concentration of the coal fired plant showed Ave. 13.85 %(10,384 ton/day). The LNG fired plants showed 3.16 %(1,031 ton/day) and 3.19 %(1,209 ton/day), respectably. Consequently, by calculating the emission factors using the above results, it was found that the bituminous coal fired power plant had the $CO_2$ emission factor average of 88,726 kg/TJ, and the LNG fired power plants had the $CO_2$ average emission factors of 56,971 kg/TJ and 55,012 kg/TJ respectably which were similar to the IPCC emission factor.

• 에너지공학
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• 제21권4호
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• pp.427-434
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• 2012

국내 500MW 석탄화력발전소에서 사용중인 역청탄 (앵글로탄)과 아역청탄 (타니토탄)을 입수하여 석탄회의 기본적인 연료 및 연소특성을 살펴보았다. 또한, 열기계분석기를 이용하여 석탄 회에 대한 고온 용융특성을 평가하고 최근 새롭게 제시된 BHEL 슬래깅 지수를 구하였다. 아역청탄인 타니토탄 회는 $1,200{\sim}1,250^{\circ}C$에서 대부분의 용융이 발생하고 있으나 역청탄인 앵글로탄 회는 상대적으로 높은 온도인 $1,550^{\circ}C$ 부근에서 급격한 용융이 발생하였다. 석탄 회의 용융특성과 석탄중의 회 함량을 고려한 BHEL 지수는 두 탄종 모두 슬래깅성이 높은 것으로 나타났다. 반면, 기존의 슬래깅 지수들은 서로 다른 슬래깅성을 보여주었다.

• 대한화학회지
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• 제4권1호
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• pp.78-80
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• 1957

Up to now, only superficial studies on the combustion velocity of smokeless fuels have been reported, while it should be a basical factor on the utilization of low quality coals and some other smokeless solid fuels. It was, therefore, difficult to choose raw material coals in manufacturing gaseous fuels. With the intent to solve above problem, we have determined combustion velocity of domestic anthracites, graphites, coalites of lignite and cokes from Japanese bituminous coal. The results show that the cokes from Japanese bituminous coal which has been used as raw material in the manufacturing gaseous fuels such as water gas, or producer gas in Korea can be replaced by some sources of domestic anthracite or coalite of lignite.

• Advances in Energy Research
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• 제4권3호
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• pp.203-211
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• 2016

A good understanding of the chemical composition and structural characteristics of a carbonaceous material is essential in conversion processes. Understanding how the composition and structural changes influence the burning behaviour of coal is important when assessing a coal's potential for utilization. To explore the potentials of a typical Nigerian coal, both conventional and advanced analytical techniques such as proximate analysis, ultimate analysis, calorific value, surface area analyser, SEM, FTIR, XRD and SAXS were employed. The results obtained from these characterizations agree favourable well with a typical South African coal that is of enormous contribution to the gross domestic product (GDP) of the nation economy.