• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.1 no.1
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• pp.62-67
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• 1991

Authors investigated size distributions of airborne mixed coal dust at drillings, coalfaces, and separating sites of underground coal mines in Taebaek, Hwasun, and Jeomchon area by ambient cascade impactors. And Respirable mass fractions were calculated from the size distributions by the ACGIH criteria.

• Resources Recycling
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• v.26 no.2
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• pp.71-79
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• 2017

Circulating fluidized bed combustion (CFBC) ash is one of useful mineralogical resources having abundant content of free lime and anhydrite, and has a self-cementitious property. Recently, considerable interest has been gained regarding the utilization of CFBC ash, along with its use in mine backfill and reclamation. Prior to adopt the use of CFBC ash in the mine backfill technology, discussion on the technology and related specification is prerequisite in the future. This paper presents a review on studies in the emerging technology of CFBC ash utilization, and provides useful information with regard to the specifications for mine backfills utilizing CFBC ash.

• Proceedings of the KSEEG Conference
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• 2002.04a
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• pp.92-94
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• 2002

• Resources Recycling
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• v.19 no.2
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• pp.54-62
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• 2010

In order to obtain the basic data for recycling of coal mine tailings, the characteristics of coal mine tailings, the formation of AMD from the tailings and the leaching of heavy metal from the tailings were studied. The samples were characterized in terms of chemical composition, mineral composition and content of heavy metal of the tailings were investigated. The effects of time, temperature, content of pyrite, sulfide minerals on the formation of AMD were also investigated. For the leaching tests, the KS method, TCLP method and column test were used. From the investigated data, we can see that the coal mine tailings can be used as aggregate for filling used gallery. We can also see that the formation of AMD from coal mine tailings can be prevented by mixing 4% or more limestone with it.

• Proceedings of the Korea Water Resources Association Conference
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• 2010.05a
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• pp.1211-1215
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• 2010

국내의 석탄자원은 1989년부터 비경제 탄광은 폐광시키고 경제성 있는 탄광을 육성하는 석탄산업 합리화시책을 실시하여, 전국 343개의 탄광이 폐광되어 현재는 5개의 탄광만이 가행되고 있다. 이들 가행광산중 강원도 삼척시 도계읍에 위치한 채탄작업을 위한 갱구 입구의 작업지역(DCM, Dogye coal mine)을 선정하여 강우 유출수 모니터링을 시행하였다. DCM지역의 수문분석 결과 연강우량의 83%는 일 강우 80 mm 이하에서 발생하였다. 또한 연강우량의 50% 이상이 40 mm 이하의 강우계급에서 발생하고 있는 것으로 나타났다. 연간 강우횟수는 약 90회 정도 발생하고 있으며, 평균적으로 4일에 1회의 강우가 발생하였다. 또한 100 mm 이상의 강우도 연평균 강수량의 13.78%를 차지하고 있어 집중호우가 총 강우량에 미치는 영향이 작지 않음을 나타냈다. 비점오염의 배출은 강우량에 의해 영향을 많이 받기 때문에 기상이변으로 게릴라성 집중호우가 많이 발생하는 요즘 큰 강우사상에 대하여 많은 대비를 해야 할 것으로 판단되었다.

• Journal of Korean Tunnelling and Underground Space Association
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• v.19 no.4
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• pp.589-609
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• 2017

This study carried out the density and energy dispersive X-ray spectroscopy and particle size analysis which are the physical characteristics of coal dust by collecting samples of coal dust in the five domestic mines to control the coal dust through ventilation in the workplace for coal mining in the country. This will contribute to a more comfortable working environment by understanding the physical characteristics of the coal dust which is derived from any hard coal produced domestically. In particular, the result of PSA analysis showed that the size of coal dust sample for this study ranged from $0.007{\sim}88.614{\mu}m$ were the particles less than $3.5{\mu}m$, the size range responsible for pneumoconiosis. To observe the flow of coal dust collected on the wind speed, the fallout of coal dust produced by the wind tunnel for the wind was measured and the particle size analysis of coal dust fallout was carried out. In addition, airborne dust is measured according to the mine velocity by using a multi-stage Anderson sampler in the mine where fine dust is generated in a large amount and the wind speed is found out to control the coal dust below $3.5{\mu}m$. In addition, natural ventilation pressure of A mine was calculated to prevent over design of the main fan.

• Resources Recycling
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• v.28 no.4
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• pp.15-22
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• 2019

Coal combustion products are generated during coal combustion and can be grouped into fly ash and bottom ash depending on collection methods. Fly ash and bottom ash can be recycled for various purposes based on their characteristics. Australia is the fourth largest coal production country in the world and reuses coal ash as cement, concrete, mine filler, and agricultural soil amendment. When fly ash is used as a supplement for cement and concrete, strength of the cement and the durability of the concrete can be improved. Use of coal combustion product for mine backfill stabilizes underground mine voids and stores a large amount of coal ash in the voids. Because of alkalinity of coal combustion products, it can neutralize acid mine drainage when used for mine backfill. In addition, it can be used as an agricultural soil amendment to improve acidity and physical properties of the soil and to supply plant nutrients. Recycling of fly ash in Australia will be further expanded because of its low trace element contents that can be toxic to plants and low radioactive element contents existing within soil background concentrations. The characteristics of coal combustion products are related to the characteristics of the coal used for combustion, and since Korea imports coal from Australia, Korean coal combustion products also can be recycled for various purposes.

• Resources Recycling
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• v.29 no.6
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• pp.41-47
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• 2020

This study was carried out to utilize the coal bottom ash generated in a circulating fluidized bed combustion boiler as a treatment agent for heavy metal ions, and experiments were conducted to remove heavy metal ions from the acid mine drainage. The batch experiments were conducted to investigate the influence of dosage of ash, initial concentration of solution on the removal capacity of heavy metal ions (Cu, Cd, Cr, Pb). The results of the experiment showed that the total removal capacity of heavy metals was 30.8 mg/L and 46.4 mg/g, respectively, under the condition that the concentration of coal ash was added as 15 g/L of heavy materials and 10 g/L of light materials. After that, a long-term column experiment was performed to determine the maximum removal capacity of heavy metal ions (Cu, Cd, Cr, Pb, As), and the removal capacity for each metal component was investigated. After approximately 60 days of operation, the maximum removal capacity of heavy metals was 23.6 mg/g at pH 9.25.

• Economic and Environmental Geology
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• v.46 no.4
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• pp.291-300
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• 2013

The potential mineral resources in North Korea are magnesite, limestone, coal, graphite, iron, gold, silver, lead, and zinc. North Korea is mainly exporting coal and iron to China(70%) and EU countries. Gold ore reserves(or resources) in North Korea are about 2,000 tons and annual production is 2 tons based on metal. Major gold mines are Sooan, Holdong, and Daeyoodong mines and six smelters are operating. Fe ore reserves (or resources) are 4.3 billion tons and annual production is about 5 million tons based on 63.5% Fe. Major iron mines are Moosan, Leewon, Eunryul, Shinwon, and Jaeryong and 7 smelters are operating. Pb and Zn ore reserves(or resources) are Pb 470,000 tons and Zn 15 million tons, and annual productions are about Pb 26,000 tons and Zn 50,000 tons based on metal respectively. Major Pb-Zn mines are Gumdock and Seongcheon mines. Magnesite ore reserves(or resources) are 2.8 billion tons (95% MgO) and annual production is about 150,000 tons. Major magnesite mines are Ryongyang, Daeheung Youth and Ssangryong mines, and 5 magnesium refractory factories are operating. Apatite ore reserves(or resources) are 340 million tons(30% $P_2O_5$) and annual production is about 300,000 tons(crude ore). Major apatite mines are Daedaeri, Dongam and Poongnyen mines. Coal is established as an important strategic fuel mineral resources and is a major energy source in North Korea. Coal ore reserves(or resources) are 18.6 billion tons and annual production is about 20 million tons. The main coal fields is located in southern Pyongan and the Jigdong mine is the biggest in North Korea.

• Proceedings of the KAIS Fall Conference
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• 2009.12a
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• pp.259-262
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• 2009

본 연구에서는 석탄광산 선탄장설비와 국소배기시스템의 일부를 모형화하여 포집특성과 유동특성실험을 수행하였으며 동일조건에서 수치해석을 수행하여 그 결과를 비교 검토하였다. case 5가 46.35%의 가장 높은 포집효율을 보였으며 실험의 3가지 변수 중 고무 커튼의 사용유무가 국소배기시스템의 포집효율에 가장 큰 영향을 미치는 것으로 판단된다. 또한 case 1, 5, 6에 대해 포집된 입자크기 확인 결과, 포집성능이 우수한 case 5가 입경 $20{\mu}m$ 초과 입자들이 약 55%로 가장 많이 포집된 것을 알 수 있었다. 따라서 제어거리는 0.5m 이상이 적절한 것으로 판단된다.