• 한국연소학회지
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• 제10권3호
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• pp.1-9
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• 2005

The characteristics of co-combustion of Korean anthracite and bituminous coal was determined in a TGA and a lab-scale CFB reactor. The combustion reactivity of Korean anthracite (E = 51.2 kcal/mol) was much lower than that of bituminous coal (E = 14.5 kcal/mol). As the addition amount of the bituminous coal into the anthracite was increased, the reactivity of the anthracite was found to be improved. The effluent rate of the emission gases from the CFB reactor was not changed appreciably when each coal burned. As the bituminous coal was added, however, the effluent rate of the emissions was increased. The unburned carbon in fly ash from the CFB reactor was decreased with increasing the ratio of bituminous coal in co-combustion. But as the ratio of the bituminous coal was larger than 40 %, the combustion reactivity was not increased any more.

• 한국환경보건학회지
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• 제22권3호
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• pp.28-36
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• 1996

The objects of this study were to investigate emissions of air pollutant the particles as well as the combustibility of the low grade domestic anthracite coal and imported high-calorific bituminous coal in the fluidized bed coal combustor. The production of air pollution from anthracite-bituminous coal blend combustion in a fluidized bed coal combustor was evaluated. The effects of air velocity and anthracite fraction on the reaching time of steady state condition was also evaluated. We used coal samples the domestic low grade anthracite coal with heating value of 2,010 kcal/kg and the imported high grade bituminous coal with heating value of 6,520 kcal/kg. The experimental results are presented as follows. The time of reaching to steady state was affected by the temperature variation. The steady state time was about 120 minute at 0.3 m/s which was the fastest. It has been found that $O_2$ and $CO_2$ concentration were reached steady state at about 100 minute. As the height of fluidized bed becomes higher, the concentration s of $SO_2$ and $NO_x$ mainly increased. The concentration of freeboard was the highest and emission concentration was diminished. Also, as anthracite fraction increased, the emission of $SO_x$ concentration was increased. But, it has been found that the variation of $NO_x$ concentration with anthracite fraction was negligible and the difference of emission concentration according to air flow rates was negligible, too. It has been found that $O_2$ concentration decreased and $CO_2$ concentration increased as the height of fluidized bed increased. As anthracite fraction increased, the mass of elutriation particles increased, and $CO_2$ concentration decreased. Also, as air velocity increased, $O_2$ concentration decreased and $CO_2$ concentration increased. Regardless-of anthracite fraction and flow rate, the combustible weight percentage in elutriation particles were high in the case of fine particles.

• 한국환경과학회지
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• 제6권3호
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• pp.267-276
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• 1997

It has been studded that combustion and the production of air pollution of anthracite - bituminous coal blend In a fluidized bed coal combustor, The objects of thIns study were to investigate mixing characteristics of the particles as well as the combustibility of the low grade domestic anthracite coal and Imported h19h calorific bltununous coal in the fluidized bed coal combustor. They were used as coal samples ; the domestic low grade anthracite coal with heating value of 2,010kca1/kg and the Imported high grade bituminous coal with beating value of 6,520kca1/kg. Also, the effects of air flow rate and anthracite fraction on the reaching time of steady state condition have been studied. The experimental results are presented as follows. The time of reaching to steady state was affected by the temperature variation. The steady state time was about 120 minute at 300sc1h which was the fastest. It has been found that $O^2$ and $CO^2$ concentration were reached steady state at about 100 minute. It has been found that $O^2$ concentration decreased and $CO^2$ concentration increased as the height of fluidlzed bed Increased. It was found that splash zone was mainly located from 25cm to 35cm above distributor. Also, as anthracite traction Increased, the mass of elutrlatlon particles Increased, and $CO^2$ concentration decreased. As gk flow rate Increased,$O^2$ concentration decreased and $CO^2$ concentration increased. Regardless of anthracite fraction and flow rate, the uncombustible weight percentage according to average diameter of elutriation particles were approldmately high In the case of One Particles. As anthracite traction and k now rate Increased, elutriation ratio Increased. As anthracite fraction was increased, exit combustible content over feeding combustible content was Increased. Regardless of anthracite fraction, size distribution of Ued material from discharge was almost constant. Over bed temperature 85$0^{\circ}C$ and excess air 20% , the difference of combution efficiencies were little. It is estimate that the combustion condition In anthracite-bituminous coal blend combustion is suitable at the velocity 0.3m/s, bed temperature 85$0^{\circ}C$, the excess air 20%.

• 한국안전학회지
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• 제11권2호
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• pp.96-101
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• 1996

The effects of coal type and mixing fraction of coal on attrition and elutriation were studied in a 15. 5cm diameter fluidized bed coal combustor. The domestic low-grade anthracite coal with heating value 2010kcal/kg and the imported bituminous coal from Australia with heating value of 6520kcal/kg were used as coal sample. It was found from the experimental that the elutriation rate inclosed with an increseing anthracite mixing fraction. The size of elutriated particle had a very wide distribution was found in this experiment. The mean size of elutriated particle increased with decreaseing anthracite mixing fraction.

• 공업화학
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• 제21권5호
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• pp.553-558
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• 2010

순환유동층에서 나타나는 국내 무연탄의 낮은 연소성을 극복하고 비산재로 배출되는 미연분의 손실을 극복하기 위하여 분탄과 비산회를 혼합하여 성형한 성형탄과 무연탄의 혼소를 0.1 MW급 순환유동층에서 수행하였다. 비교 시험에서 원탄 연소는 다량의 미분의 비산과 연소로 상부에서의 과열을 일으켰으나 조립탄 연소의 경우 미분을 제거하였으므로 일정한 온도에서 연소되었고 운전이 가장 안정적이었다. 조립탄과 원탄이 혼합된 석탄은 다소 운전이 불안하였으나 원탄만을 연소시킬 때보다는 안정적 연소가 가능하였다. 조립탄에 성형탄을 혼합한 경우 조립탄 연소의 경우와 같이 원활한 운전이 가능하였다. 본 연구는 상용 순환유동층 보일러에서 성형탄 혼소가 국내 무연탄의 연소성 개선에 도움이 됨을 보여 주었다.

• 한국기후변화학회지
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• 제4권1호
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• pp.27-39
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• 2013

본 연구에서는 국내에서 사용되는 무연탄을 국내무연탄, 원료용 수입무연탄, 연료용 수입무연탄으로 분류하여 각각의 발열량 및 온실가스 배출계수를 산정하였다. 본 연구에서 산정된 온실가스 배출계수는 국내무연탄이 $111,477{\pm}4,508kg\;CO_2/TJ$, 원료용 수입무연탄이 $108,358{\pm}4,033kg\;CO_2/TJ$, 연료용 수입무연탄이 $103,927{\pm}8,367kg\;CO_2/TJ$로 산정되었다. 산정된 배출계수를 이용한 온실가스 배출량은 $6,216,942ton\;CO_2$로 무연탄을 상세히 구분하지 않고 산정한 온실가스 배출량보다 12.7% 적게 나타났다. 이에 따라, 무연탄을 상세히 분류하여 활동자료를 수집하는 것이 무연탄의 활동자료를 통합하여 수집하는 것보다 정확한 온실가스 배출량을 산정할 수 있다고 판단된다. 또한, 국내에서 사용되고 있는 무연탄의 경우 IPCC에서 제시하고 있는 무연탄과 특성이 다르기 때문에 국가 온실가스 인벤토리 향상을 위해 무연탄을 용도별로 분류하여 산정해야 한다.

• 플랜트 저널
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• 제6권2호
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• pp.70-77
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• 2010

This study investigated the characteristics of co-combustion of mixed anthracite (domestic and Vietnam) and bituminous coal (Sonoma, Australia) at circulating fluidized bed boiler in Donghae thermal power plant when mixing ratio of bituminous coal is variable. Co-combustion of bituminous coal contributes to improvement in general combustion characteristics such as moderately retaining temperature of furnace and recycle loop, reducing unburned carbon powder, and reducing discharge concentration of NOx and limestone supply owing to improvement in anthracite combustibility as the mixing ratio was increased. However, bed materials were needed to be added externally when the mixing ratio exceeded 40% because of reduction in generating bed materials based on reduction in ash production. When co-combustion was conducted in the section of 40 to 60% in the mixing ratio while the supplied particles of bituminous coal was increased from 6 mm to 10 mm, continuous operation was shown to be possible with upper differential pressure of 100 mmH2O (0.98 kPa) and more without addition of bed materials for the co-combustion of mixed anthracite and bituminous coal (to 50% or less of the ratio) and that of domestic coal and bituminous coal (to 60% of the ratio).

• 한국환경보건학회지
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• 제23권3호
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• pp.102-108
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• 1997

It has been studied that SO$_2$ removal efficiency of anthracite-bituminous coal blend combustion in a fludized bed coal combustor. The objectives of this study were to investigate SO$_2$ removal characteristics of coal blend combustion with Ca/S, anthracite fraction, bed temperature, and limestone size. The experimental results were presented as follows First, the effect of the desulfurization by the dia size of limestone was great and SO$_2$ removal efficiency was highest in limestone dia 631 $\mu$m. Second, as air velocity increased, the desulfurization rate decreased a little. But the difference of the desulfurization rate according to air velocity was not too large. As the height of fluidized bed combustor increased regardless of air velocity, SO$_2$ concentration tends to increase largely. Third, as Ca/S mole ratio incresed, SO$_2$ desulfurization rate incresed rapidly up to Ca/S mole ratio 3 while the desulfurization rates did not increse too largely in the range of more than the level. Forth, the bed temperature had a great effect on the desulfurization rate and the desulfurization rate tended to increase slightly as anthracite fraction increased.

• 공업화학
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• 제10권4호
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• pp.586-591
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• 1999

유연탄과 무연탄 및 유, 무연탄의 연소특성을 해석하기 위하여 내경 0.109 m의 유동층반응기에서 회분석 석탄주입에 따른 유동화특성과 연소특성 실험을 수행하였다. 온도변화곡선, 압력요동특성치를 이용하여 회분식유동층에서 유연탄과 무연탄 및 혼합석탄의 연소특성을 측정하였다. 유연탄과 무연탄의 입자크기, 두 석탄의 혼합비, 유동화매질의 입자크기에 따른 영향을 고찰하였다. 유연탄과 무연탄의 혼합연소시 무연탄의 혼합비가 30 %인 경우가 유연탄의 연소속도 및 연소거동이 최적으로 나타났다. 저품위 고회분 무연탄의 경우 유동화특성보다 연소특성에 의한 영향이 더욱 크게 나타났다. 또한 유동층의 유동화 특성에 의하여 연소거동이 변화됨을 알 수있었다.

• 에너지공학
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• 제1권1호
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• pp.102-110
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• 1992

The determination of production level of the domestic anthracite coal is an important issue in the national energy strategy. It is also closely related to the energy mix scenarios in the future. The objective of the paper is to discuss and analyze the options of expanding anthracite coal demand in the utility sector. The observed options are including; (1) New pulverized system of the 200 and 500 MW level, (2) Atmospheric Fluidized Bed Combustion (AFBC), and (3) Pressurized Fluidized Bed Combustion (PFBC). Special emphasis is placed on the considerations in estimating the effects on the electric system costs and government subsidies when the options are introduced in the utility sector.