• Applied Chemistry for Engineering
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• v.21 no.5
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• pp.553-558
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• 2010

To solve the problems of the low combustion activity of Korean anthracite and the abundant loss of unburned carbon in fly ash, pellet coal was fabricated from coal fines and fly ash, and the mixed combustion of coarse coal with the pellet coal was examined in the circulating fluidized bed combustor of a 0.1 MW scale test unit. In the combustion of the raw coal only, the significant amount of coal fines was entrained, resulting in overheat at the top of the combustor. With the coarse coal that most fines were eliminated, however, the combustion temperature was maintained stable. The mixed combustion of coarse and raw coals was also feasible even though it often went unstable. The mixed combustion of the coarse coal with the pellet coal was as stable as the coarse coal combustion, showing a promise that the combustion of the Korean anthracite in commercial circulating fluidized bed boilers could be further enhanced.

• Journal of Climate Change Research
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• v.4 no.1
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• pp.27-39
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• 2013

In this study, the anthracite coal being used as fuel in Korea were classified into different types. These types include the domestically produced anthracite, imported anthracite used as raw material, and imported anthracite used as fuel. Each of the calorific values and greenhouse gas emission factors were calculated. The calculation of greenhouse gas emission factors resulted in the domestically produced anthracite as $111,477{\pm}4,508kg\;CO_2/TJ$, the imported anthracite used as raw material as $108,358{\pm}4,033kg\;CO_2/TJ$, and anthracite used as fuel was displayed as $103,927{\pm}8,367kg\;CO_2/TJ$. Additionally, the amount of greenhouse gas emission based on these calculated emission factors was displayed as $6,216,942ton\;CO_2$, which resulted as 12.7% lower than the green house gas emission amount which was calculated without distinguishing anthracite coal in details. Therefore, collecting activity data through a detailed classification of anthracites facilitate a more accurate calculation of greenhouse gas emission amount compared to collecting activity data through combination. Furthermore, since the anthracite coal used domestically possesses characteristics differing from the anthracite coal proposed by the IPCC, anthracite coal should be classified for each purpose and calculated for the improvement of the national greenhouse gas inventory.

• Journal of Energy Engineering
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• v.5 no.2
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• pp.170-175
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• 1996

This study is to determined the activation energy from TGA experimental data for the bituminous and anthracite coals of three kinds which are being used in the domestic coal-fired power plants. TGA experimental data indicate that the weight loss temperature of bituminous coal is 200$^{\circ}C$ higher than that of anthracite coal. Activation energy of bituminous coal is in the range of 14∼20 Kcal/mole compared with 37∼55 Kcal/mole of anthracite coal. A reduction of particle size of coals results in the decrease of activation energy and activation energy has a good correlation with the weight loss percent of coal in the TGA experiment. Addition of CaCO$_3$ on anthracite coal caused to decrease the activation energy of 1∼23 Kcal/mole while activation energy of bituminous coal do not change significantly.

• Analytical Science and Technology
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• v.5 no.4
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• pp.433-441
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• 1992

Chemical composition and fusibility of coal ash were measured for 23 Korean anthracite coals. The relationship between chemical properties and fusion temperature of coal ash was investigated. The slagging and fouling in firing the pulverized coal for boiler was assessed for the coal samples. It was found that most ashes contained more than 80% of $SiO_2$ and $Al_2O_3$ whereas less than 1% of $Na_2O$. And also fusion temperature of ashes occured relatively higher for Korean coals. Therefore it can be predictable that the slagging and fouling formation has a little problem in a pulverized coal firing system. A base/acid ratio did show a good correlation with fusion temperature for these coal ashes.

• Plant Journal
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• v.11 no.3
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• pp.46-52
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• 2015

200MWe 순환유동층보일러인 A화력발전소는 정부정책에 의해 국내 무연탄만을 연료로 배정받아 운영되었다. 하지만 무연탄에 대한 민간수요 증가에 따른 정부의 정책변경에 따라 유 무연탄 혼탄을 2000년대 후반부터 시행하고 있다. 하지만 기동시 석탄 투입온도는 여전히 무연탄 전소시의 기준온도인 $600^{\circ}C$에 석탄을 투입하고 있는 실정이라 기동시간 지연의 한 원인으로 작용하고 있고 기동 중 소요되는 경유의 과다소비라는 고질적인 문제점을 안고 있다. 이에 본 연구에서는 A화력에서 사용되는 석탄에 대한 공업분석과 원소분석을 통하여 비교적 휘발분이 많고 반응성이 좋은 러시아산 유연탄(Suek) 연소에 따른 경유에서 석탄으로의 연료교체시 경제적인 시점을 예측하였다. 실험결과 러시아산 유연탄 (Suek) 연소시 투입가능온도는 연소전환율이 90%이상이 되는 연소최대온도($426^{\circ}C$)가 기술적, 경제적으로 가장 적합한 것으로 예상하였다.

• Clean Technology
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• v.23 no.4
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• pp.364-377
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• 2017

In this study, to improve the low surface area of domestic anthracite as raw materials of activated carbon, characteristics on chemical activation and VOCs adsorption of activated carbon according to mixing ratio of anthracite and lignite. For these, properties of raw materials, parameter characteristics of preparation processes for activated carbon, and VOCs adsorption characteristic of the prepared activated carbon are analyzed. The experimental results showed that, the domestic anthracite had disadvantages of high contents for ash and lead, arsenic, which were exceeded for the heavy metal limits, in the properties of raw materials. To improve these diadvantages, using the mixing ratio of anthracite and lignite, and the optimum conditions for pretreatment, activation, washing, and pellitization process, the activated carbon had a range of BET (Brunauer-Emmett-Teller) surface area of $1,154{\sim}1,420m^2g^{-1}$ with mesopore development and hydrophobic surface property. The carbons were satisfied with the quality standard for granular activated carbon, and had similar physicochemical properties with the commercial activated carbon. The minimum mixing condition for commercial VOCs activated carbon performance must have the caloric value of above $5,640kcal\;kg^{-1}$, and the carbon had higher adsorption capacity with order of xylene > toluene > benzene according to more higher molcular weight and hydrophobic property.

• Journal of Energy Engineering
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• v.8 no.2
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• pp.279-284
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• 1999

Thermal analyses were conducted in a thermogravimetric analyzer by isothermal technique in order to characterize the Korean anthracites-nitrogen oxides reaction. The tested coal sample was Dogae anthracites and compared with SP-1 graphite. Carbon-NO and carbon-N$_2$O reactions were carried out with respect to isothermal reaction temperatures (550$^{\circ}C$-900$^{\circ}C$) and reactant gas partial pressures (5 kPa∼20 kPa). In NO reaction, measured reaction orders of NO concentration and activation energy were 0.45∼0.96 and 39∼l12 kJ/mol, respectively. In N$_2$O reaction, measured reaction orders of N$_2$O concentration and activation energy were 0.62∼0.87 and 190∼215.3 kJ/mol, respectively. Compared the Korean anthracites-nitrogen oxides reaction with the combustion reaction, the reaction rate in the oxidation below 700$^{\circ}C$ decreases in the order O$_2$>NO>N$_2$O. But above 700$^{\circ}C$, the reaction rate of N$_2$O is faster than that of NO.

• Proceedings of the KSEEG Conference
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• 2003.04a
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• pp.213-216
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• 2003

1990년대에 들어와서 미국을 비롯한 석탄자원 부국들은 석탄층메탄가스자원을 에너지로 이용하는데 성공하였으며 현재 그 생산과 이용규모를 빠르게 확대해 나가고 있다. 우리나라의 경우 약 15억 톤의 무연탄자원이 확인되지만 수요처 상실로 1980년대 후반부터 석탄합리화 과정을 통해 석탄생산량은 2700만 톤/년에서 400만 톤/년 이하로 급감 했으며 가행탄광 수도 350여 개에서 10개로 감소됐다. 이러한 추세로 보면 국내무연탄자원은 사실상 사장 화 될 처지에 놓이게 된 것이다. (중략)

• Proceedings of the KSEEG Conference
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• 2001.04a
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• pp.410-414
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• 2001

• Korean Chemical Engineering Research
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• v.44 no.5
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• pp.489-497
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• 2006

The economical efficiency of conversion of the PC (pulverized coal) firing boiler to the CFB (circulating fluidized bed) boiler which used Koran anthracite as fuel was evaluated. The economic feasibility study was also carried out with regard to maintenance of the existing PC boiler. The sensitivity of economical efficiency with variation of the electric power and coal industry and the policy of government was analyzed and compared. As a results of the evaluation, the economical efficiency of maintenance of the existing PC boiler was higher than that of conversion to the CFB boiler because of the special policy of the government for Korean anthracite. However, the conversion to the CFB boiler was more economically attractive from a point of view of effective use of energy resources and future electric power industry. Additionally, the fund support for electric power industry using Korean anthracite would be effective as changing the policy of the government.