• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 춘계학술대회 논문집
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• pp.255-262
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• 2011

2010년 철도화물 수송톤수는 약 39백만 톤이며, 이 중 석탄수송은 약 6.2백만 톤으로 전체 철도수송의 약 15.7%를 차지하고 있다. 또한 철도화물 수입 중 석탄수송이 약 15.8% 수준인 517억 원으로 철도수송 품목에 있어서 수송량 및 수익에 있어서 3번째로 큰 비중을 나타내고 있다. 그러나, 철도수송에서 큰 비중을 차지하고 있는 석탄은 정부의 무연탄 감산정책과 주로 트럭운송에 의지하는 비발전용 무연탄에 대한 우선 공급으로 철도수송이 크게 감소하고 있으며, 이에 대해 석탄취급이 많은 강원권 물류 수송수익에 큰 영향을 주고 있다. 이에 따라 본 연구에서는 강원권 화물운송 중 석탄수송이 감소하는 근본적인 원인에 대해 살펴보고, 이를 해결할 수 있는 방안에 대해 살펴보았다.

• 자원환경지질
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• 제22권2호
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• pp.141-150
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• 1989

In order to make economic and geological evaluation of coal in Korea, proximate and ultimate analyses were carried out as well as coal petrological studies such as maceral analyses, vitrinite reflectance and sporinite fluorescence measurement. The coeffcient of correlation between each factor of both conventional utilization and coal petrological parameters were studied as in Table 5 and 6. Their conclusions were as follow: (1) for anthracite, the good parameters of coal rank are mean vitrinite reflectance, carbon content, hydrogen content and H/C atomic ratio: (2) for brown coal and sub-bituminous coal, the good parameters of coal rank are carbon content, calorific value, moisture content, hydrogen content, oxygen content and O/C atomic ratio as well as vitrinite reflectance and sporinite fluorescence. An attempt is made to infer the coalforming environment by utilization of coal petrological analyses and to make comparison of coal analyses with proximate and ultimate analyses throughout the island arc region including Japan, Philippine and Indonesia and continental region including USA, Canada and Australia. As a result, meceral composition of Paleozoic and Mesozoic anthracite are similar to that of the Paleozoic continental coals, which were formed under dry conditions or low water table, but the coalification degree suddenly increased during Daebo orogeny (middle Jurassic to lower Cretaceous). The Tertiary coal resembles those of Tertiary island arc region coal characterized by higher calorific value, volatile matter content and H/C atomic ratio and by the formation of coal under wet conditions or higher water table.

• 한국환경과학회지
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• 제23권3호
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• pp.379-386
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• 2014

Adsorption and biodegradation performance of tetracycline antibiotic compounds such as ttetracycline (TC), oxytetracycline (OTC), minocycline (MNC), chlortetracycline (CTC), doxycycline (DXC), meclocycline (MCC), demeclocycline (DMC) on granular activated carbon (GAC) and anthracite-biofilter were evaluated in this study. Removal efficiency of seven tetracycline antibiotic compounds showed 54%~97% by GAC adsorption process (EBCT: 5~30 min). The orders of removal efficiency by GAC adsorption were tetracycline, demeclocycline, oxytetracycline, chlortetracycline, doxytetracycline, meclocycline and minocycline. Removal efficiencies of seven tetracycline antibiotic compounds showed 1%~61% by anthracite biofiltration process (EBCT: 5~30 min). The highest biodegradable tetracycline antibiotic compound was minocycline, and the worst biodegradable tetracycline antibiotic compounds were oxytetracycline and demeclocycline.

• Journal of Advanced Marine Engineering and Technology
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• 제5권1호
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• pp.28-33
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• 1981

The characteristics of typical 35 kinds of domestic anthracites among 155 kinds are studied to find the calculation formula for the required quantity of air and the combustion gas quantity. 1) The author's calculation formulae are as follows: ${A_0}={\frac{1, 000}{1, 064}}{H_1}+0.086(Nm^3/kg)$ ${G_0}={\frac{1, 000}{1, 110}}{H_1}+0.234(Nm^3/kg)$(1) Theoretically required quantity of air (2) Theoretical quantity of combustion gas 2) Theoretical quantity of air in combustion of domestic anthracite is always estimated more with Rosin's formula than author's one in the typical domestic anthracites which have the lower calorific value between 3, 000-8, 000 Kcal/kg and the difference of the calculated quantity of air becomes small, as the calorific value increases. 3) Theoretical quantity of combustion gas is estimated more by author's formula than by Rosin's one with the domestic anthracites which have more calorific value than 6, 700 Kcal/kg and is estimated less in the under range of the above calorific value. 4) Theoretical quantity of required air and quantity of combustion gas of domestic anthracite show ${\pm}$4% difference by Rosin's formulae in comparison with results of actual analysis, and about ${\pm}$1.5% by the author's one.

• 한국환경보건학회:학술대회논문집
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• 한국환경보건학회 2005년도 국제학술대회
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• pp.381-385
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• 2005

Characterization of particle behavior is becoming more important in performance evaluation of water treatment system as well as in operation of the system because conventional parameter, turbidity has lack of explaining ability on small sized microorganisms such like Cryptosporidium etc. Accordingly, particle counter has been introduced in evaluation and operation of the treatment system. However researches on the relationship between turbidity, particle count and/or different sand/anthracite sizes have not been concurrent. Therefore in this study, the relationship was investigated to improve performance evaluation of sand filter so as to help choosing sand/anthracite effective size as a design parameter of water treatment facility. According to the results, too small or too large effective size media filter reached to turbidity limit(0.1 NTU)earlier. However, because shallow sand layer may cause early breakthrough, the depth of sand layer should be provided enough in order to compromise water quality and productivity.

• 한국항해학회지
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• 제11권1호
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• pp.1-38
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• 1987

The amount of cargoes by cargo vessels has increased tremendously during the last decade due to the great growth of korea economy. But in spite of this trend, there is rarely the substantial analyzed on the operational status of coastal shipping. In this paper, the characteristics of seaborne cargo and traffic flow of coastal shipping surveyed in detail through the statistical and the origintain and destination (O.D) analysis. Also, the basic ship's tonnage of coastal shipping representing the minimum tonnage which is capable of carrying the given seaborne cargo is suggested through the computer simulation using the data of 1985 year. The results are as follows; 1) the about 80% of total coastal traffic volume is going in/out to the port of Incheon, Busan, Pohang, Samil, Bukpyung, Mukho, Samchuk, and Jeju. 2) The main cargo items such as oil, iron material, cement, anthracite grain, fertilizer, other ore are reached to the about 70% of total amount of coastal trade. 3) ship's tonnage going in/out to the port of Bukpyiung, Busan, Pohang is increasing linearly year by year, and the amount of oil, iron material, cement, anthracite, grain, fertilizer, other ore are also increasing in linear pattern. 4) As a result of simulation, the optimum (basic) ship's tonnage.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2002년도 제24회 KOSCO SYMPOSIUM 논문집
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• pp.237-246
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• 2002

가압유동층연소로(bed dia. 0.17m, freeboard dia. 0.25, total height 5m)에서 국내무연탄을 연소시켜 이에 대한 탈황특성을 고찰하였다. 실험은 압력($2{\sim}6atm$), 요동층온도(($850{\sim}950^{\circ}C$), 과잉공기(10, 20, 30,%)등의 조건과, 탈황을 위한 Ca/S몰비(($0.8{\sim}4.8$)가 탈황특성에 미치는 영향을 고찰하였다. 결과적으로, 본 연구의 실험범위에서 연소효율은 $80{\sim}99%$를 보였고, 연소온도, 압력 그리고 과잉공기가 증가 할수록 증가하였다. 배가스중의 $SO_2$배출농도는 압력, Ca/S몰비가 증가함에 따라 감소하였다. 탈황율은 상압에서 층(bed)온도의 증가에 따라 감소하였다. 운전압력이 증가함에 따라 탈황율의 감소폭이 둔화되었다. 과잉공기가 증가함에 따라 탈황율은 증가하는 경향을 나타냈다. 각각의 운전압력에서 과잉공기의 증가에 따라 약 10%의 증가폭을 보였다. 국내무연탄을 연소하는 경우 운전압력 4atm일 때 Ca/S몰비는 4이상 주입하여야 하고, 6atm일 때 Ca/S 몰비가 2.5이상주입하여야 150ppm이하를 보여 배출규제치를 만족하는 것을 보였다.

• 산업기술연구
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• 제7권
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• pp.27-47
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• 1987

Fine anthracite is very difficult to upgrade by conventional processes such as gravity concentration or froth flotation, because large quantities of fine coals are generated at the mining and preparation stages and a significant portion of these fine coals are mixed with gangue minerals. This study, therefore, was carried out for the purpose of improving recovery of low ash clean coal, effective beneficiation of low-grade coking coal and removal of sulphur from high-sulphur coals by employing the method of selective agglomeration using oil or polystrene flocculants, for coals which are generally hydrophobic in nature will be extracted by using flocculants. Studies were performed by varying solid concentration, concetration of bridging liquid, mixing speed and mixing time, balling speed and balling time, dispersant dosage, flocculant dosage, pulp pH, and particle size. The results were : when the methods of the oil agglomeration and selective flocculation were employ(in the two process the sample was ground to the size of -74 micron), 1) ash content of the agglomerated coal was 9.85, 7.83%, 2) combustibel recovery of it was 98.5%, 93.5%, respectively. It was observed in selective flocculation that polystyrene is an effective flocculant for coal, De-entrapment of shale from the concentrate flocculated by mechanical agitation was necessary for substantional reductions in final ash content.

• Journal of Preventive Medicine and Public Health
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• 제14권1호
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• pp.75-80
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• 1981

Due to rapid industrialization and economic development, the occupational diseases have appeared as one of the social problems in Korea. Up until now little has been known about the prevalence rate, predisposing factors and symptomatology of the occupational disease due to localized vibration in Korea. The researcher intends to investigate the prevalence rate and affecting factors of the occupational disease due to localized vibration among rock-drillers in the anthracite mines. A total of 135 rock-drillers were interviewed and examined from May 15th to 31th, 1980. The results were revealed as follows; 1. The prevalence rate of the vibration syndrome among rock-drillers was 12.6%. 2. The latent period of the vibration syndrome was 6.8 years. 3. The prevalence rate of the vibration syndrome was not significantly different between smokers and non-smokers. 4. With the increase of total vibration exposure time, the prevalence rate of the vibration syndrome increased also. 5. The average vibration sensation threshold was high (6.4dB) in stage 1 of the vibration syndrome and low (-0.6dB) in stage 0. 6. The average pain sensation threshold was high (4.4g) in stage 1 of the vibration syndrome and low (2.5g) in stage 0.

• 에너지공학
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• 제10권3호
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• pp.243-252
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• 2001

가압열중량분석기를 이용하여 비등온법에 의해 상온부터 100$0^{\circ}C$까지 온도를 상승시키면서 압력(1~l6기압)과 승온속도(heating rate, 15, 20, $25^{\circ}C$/min)의 변화에 따른 국내무연탄의 연소반응특성을 측정 및 해석하였다. 주어진 승온속도에서 압력이 증가함에 따라 반응속도가 증가하였으며 이와 같은 경향은 압력 증가에 따른 활성화에너지의 감소 때문으로 사료되었다. 압력이 1기압에서 16기압으로 증가함에 따라 Freeman과 Carroll$^{[11]}$ method에 의해 결정된 반응차수는 1.04에서 1.30차까지 선형적으로 증가하였으며 활성화에너지는 47.37㎉/mol에서 14.42kca1/mol로 감소하였다.