• Resources Recycling
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• v.20 no.4
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• pp.3-22
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• 2011

Until recently, domestic high grade limestone have mainly mined so high grade limestone deposits have reduced. Because of exhaustion of high grade limestone, mine of limestone have moved from ground to deep position, the grade of limestone become lower because the amount of impurities and colored mineral increased as mining position become deeper. This paper was described about grade improvement of limestone to make a high grade limestone and suitable quality of limestone products by analysis of ore genesis and characteristics, supply and demand situation, use patterns and application standards of domestic lime-stone.

• Journal of the Mineralogical Society of Korea
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• v.17 no.4
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• pp.339-355
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• 2004

Locality of domestic high-Ca limestones can be divided into three districts, i.e., (1) the Jecheon-Danyang area, (2) the Samcheok-Taebaek-Jungsun area, and (3) the Uljin-Andong area, in accordance with their geologic background and type of the deposits. Except for some crystalline limestones from the Jecheon-Danyang area, domestic high-Ca limestones were mostly recrystallized and Ca-enriched by the effects of hydrothermal alteration and/or thermal metamorphism. The lime-stones can be also divided into crystalline limestone type, marble type, micro- and mega-crystalline calcite types on the basis of their composition, crystallinity, and mineral facies. An applied-mineralogical characterization of the high-Ca limestones was done through the systematic analyses and tests for the limestones. The high-Ca limestones from the area (1), which are megascopic ally close to the original limestone in lithology, display lower whiteness, higher contents of CaO (51 ～ 54 wt.%), low crystallinity, and fine-grained texture. Two typical hydrothermal types of the high-Ca limestones from the area (2), i.e., micro- (mostly 0.2～0.3 mm) and mega-crystalline (2～15 em) calcite types, have comparatively higher whiteness and rather variable CaO contents (50～55 wt.%) with exhibiting quite different crystallinity each other. The micro-crystalline calcite type is especially dominant in this area, and has comparatively uniform crystallinity and homogeneous composition. Compared to these limestones, the high-Ca limestones from the area (3) show remarkable differences in grade and quality according to their types of deposit and occurrence. Based on these mineral characters and chemical composition, a possible scheme for industrial uses of the domestic high-Ca limestones was suggested.

• Mineral and Industry
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• v.15 no.1
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• pp.1-14
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• 2002

국내에서 석회석 산업은 대규모의 시장이 형성되어 있는 국가적 기간산업이고, 석회석의 부존자원으로서의 잠재성도 크다는 것은 주지의 사실이다 그러나 값싼 소재자원으로서 대규모 개발 및 수요 특성을 가졌던 종래의 석회석 산업에서는, 품위 및 품질 개념의 인식이나 구분도 없이 단순히 화학분석 자료에만 의존하여 개발과 가공이 이루어질 수 밖에 없었다. 최근에 대두되는 환경문제와 생산원가의 상승으로 인해서 국내 석회석 산업계에는 국내 석회석 자원의 효율적 개발과 부가가치의 증진이 절실히 요구되는 상황이다. 이를 위해서는 종래의 화학분석치 일변도의 석회석 평가방식을 지양하고, 보다 합리적인 응용광물학적 광석평가 방식이 적용되어야 할 것이다. 석회석의 광물상, 광물조성 및 광물특성을 그 용도별로의 품위 및 품질 개념을 적용해서 평가함으로써, 우리의 소중한 자연의 기반물질이자 부존자원인 국내산 석회석을 효율적으로 개발 및 가공하는 지혜가 필요할 것으로 여겨진다. 이에 따라 석회석에 대한 새로운 관점에서의 평가 개념을 국내산 주요 고품위 석회석을 대상으로 논의하였다. 또한 이를 토대로 국내산 석회석의 효율적 개발과 부가가치 제고를 위한 새로운 광물특성 평가방안을 제시하였다.

• Geophysics and Geophysical Exploration
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• v.20 no.3
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• pp.137-145
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• 2017

High-grade limestone applied to various chemical industries is abundant within upper Pungchon formation in Taebaeksan basin, South Korea. Geophysical exploration is one of the most efficient methods to investigate subsurface geological structure in an extensive area. Since the geophysical exploration for the high-grade limestone has rarely been conducted in Korea, its appropriate strategy has not been set up yet. In this study, we focused on to suggest the reasonable strategy and accumulate geophysical databases which are essential for interpreting geophysical images by characterizing laboratory physical properties of in-situ rocks. Hence, rocks were obtained from drilled cores consisting of lower Hwajeol formation, Pungchon formation, and dykes in Jeongseon area, Gangwon province. Geophysical laboratory experiments and petrography of the rocks were conducted. Since susceptibility values of the rocks in Pungchon Formation were obviously lower than those of upper Hwajeol and dykes, it is considered that the lithological boundaries could be distinguished by magnetic survey. In addition, electrical properties of the rocks in middle Pungchon formation were relatively different compared with those of upper/lower Pungchon formations. Thus, induced polarization is shown to be able to detect the high-grade limestone in upper Pungchon formation.

• Cement Symposium
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• s.40
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• pp.20-28
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• 2013

• Korean Chemical Engineering Research
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• v.57 no.5
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• pp.743-748
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• 2019

This study focuses on the simulation of wet flue gas desulfurization process for improving the production of gypsum by the utilization of low-grade limestone. At present, high-grade limestone with a $CaCO_3$ content of 94% is used for producing merchantable gypsum. In modeling process, a lot of reactions are considered to develop model. First, the limestone dissolution is simulated by RSTOIC model. Second, SOx absorption and crystallization is used by RCSTR model. Finally the gypsum is separated by using SEPERATORS model. Modeling steps make it easy to reflect further side reactions and physical disturbances. In optimization condition, constraints are set to 93% purity of gypsum, 94% desulfurization efficiency, and total use of limestone at 3710 kg/hr. Under these constraints, the mass flow of low-grade limestone was maximized. As a result, the maximum blending quantity of low-grade limestone for 2,100 kg of high-grade limestone that satisfies constraints is about 1,610 kg.

• Proceedings of the Mineralogical Society of Korea Conference
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• 2002.10a
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• pp.1-15
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• 2002

조사지역에는 고생대 캠브리아기의 장산규암층, 묘봉층, 풍촌층, 화절층 및 오도비스기의 동점층, 두무동층, 막동층, 그리고 이들과 부정합 관계인 중생대 쥬라기의 사평리 역암이 분포한다. 위의 지층들은 북동-남서방향으로 발달하는 두 개 조의 드러스트 단층과 이에 수반된 후향 드러스트 단층 및 습곡구조에 의해 분포가 지배된다 이들 지층 중 경제 지층인 풍촌층은 암상의 특성에 따라 하부석회암대, 중부백운암대, 상부석회암대(고품위대)로 세분되며, 이 중 상부석회암대가 고품위용으로 개발대상이 된다. 상부석회암대는 백색-유백색의 치밀질 괴상석회암, 담회색 괴상 석회암, 어란상 석회암 등으로 구성되는데, 평균품위는 $SiO_2\;0.40\%,\;A1_2O_3\;0.15\%,\;Fe_2O_3\;0.15\%,\;CaO\;54.2\%,\;MgO\;1.07\%,$ 백색도 85.7로 중탄용이나 생석회 및 소석회 등 화학공업용으로 사용가능한 범위를 보여준다 고품위대의 두께는 평균 약 40m이나 드러스트 단층 등의 구조요소에 의해 $2\~3$회 반복되어 분포하기도 하고 지역에 따라 두께가 $80\~90m$까지 두꺼워지기도 한다. 상부석회암대의 석회석을 중탄용, 소성용, 탈황용 등으로 개발을 위해서는 사전에 충분한 정밀시추탐사를 시행하여 그 부존규모 및 개발가능구간 확인이 선행되어야 한다.

• Proceedings of the KSEEG Conference
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• 2002.10a
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• pp.1-15
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• 2002

조사지역에는 고생대 캠브리아기의 장산규암층, 묘봉층, 풍촌층, 화절층 및 오도비스기의 동점층, 두무동층, 막동층, 그리고 이들과 부정합 관계인 중생대 쥬라기의 사평리 역암이 분포한다. 위의 지층들은 북동-남서방향으로 발달하는 두 개 조의 드러스트 단층과 이에 수반된 후향 드러스트 단층 및 습곡구조에 의해 분포가 지배된다 이들 지층 중 경제 지층인 풍촌층은 암상의 특성에 따라 하부석회암대, 중부백운암대, 상부석회암대(고품위대)로 세분되며, 이 중 상부석회암대가 고품위용으로 개발대상이 된다. 상부석회암대는 백색-유백색의 치밀질 괴상석회암, 담회색 괴상 석회암, 어란상 석회암 등으로 구성되는데, 평균품위는 SiO$_2$ 0.40%, A1$_2$O$_3$ 0.15%, Fe$_2$O$_3$ 0.15%, CaO 54.2%, MgO 1.07%, 백색도 85.7로 중탄용이나 생석회 및 소석회 등 화학공업용으로 사용가능한 범위를 보여준다. 고품위대의 두께는 평균 약 40m이나 드러스트 단층 등의 구조요소에 의해 2～3회 반복되어 분포하기도 하고 지역에 따라 두께가 80～90m까지 두꺼워지기도 한다 상부석회암대의 석회석을 중탄용, 소성용, 탈황용 등으로 개발을 위해서는 사전에 충분한 정밀시추탐사를 시행하여 그 부존규모 및 개발가능구간 확인이 선행되어야 한다.

• Economic and Environmental Geology
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• v.52 no.1
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• pp.107-118
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• 2019

Two assertions about the process the formation of the high-purity limestone in the Taebaeksan Basin, categorized into syngenetic and epigenetic origin, are verified on the basis of its oxygen-carbon stable isotopic characteristics. The carbonate rocks sampled from the selective six high-purity limestone mines and several outcrops in the Daegi formation are featured by various colors such as the gray, light gray and dark gray. They show a wide range of oxygen stable isotope ratios (4.5 ~ 21.6 ‰), but a narrow range of carbon stable isotope ratios (-1.1 ~ 0.8 ‰, except for vein calcite), which means that they had not experienced strong hydrothermal alteration. In addition, there is no difference in the range of the oxygen stable isotope ratios by mine and color, and it is similar to the range from surrounding outcrop samples. These results indicate that the effect of the hydrothermal alteration were negligible in the generation of high-purity limestone in deposit scale. Whereas, the carbonate rocks can be divided texturally into two groups on the basis of an oxygen isotope ratio; the massive-textured or well-layered samples (>15 ‰), and the layer-disturbed (or layer-destructed) and showing over two colors in one sample (<15 ‰). In the multi-colored samples, the bright parts are characterized by the very low oxygen stable isotope ratios, compared to the dark parts, implying the increase in brightness of the carbonate rocks could be induced by the interaction between hydrothermal fluid and rock. However, these can be applied in a small scale such as one sample and are not suitable for interpretation of the generation of high-purity limestone as a deposit scale. In particular, the high oxygen isotope ratios from the recrystallized white limestone suggest that hydrothermal fluids are also rarely involved during recrystallization process. In addition, the occurrences of the high-purity limestone orebody strongly support the high-purity limestone in the area are syngenetic rather than epigenetic; the high-purity limestone layers in the area show continuous and almost horizontal shapes, and is intercalated between dolomite layers. Consequently, the overall reinterpretation based on the sequential stratigraphy over the Taebaeksan basin would play an important role to find additional reserves of the high-purity limestone.

• Journal of the Mineralogical Society of Korea
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• v.18 no.2
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• pp.135-144
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• 2005

In the high-Ca limestone zone of the Pungchon Formation of the Lower Chosun Supergroup, cryptocrystalline alterations with reddish brown color occur as fissure-fillings or coatings, which was originated from the upper formation, i. e., the Hwajeol Formation. The precipitates result in degradation and contamination of the high-Ca limestone ore in grade and quality, showing characteristic occurrence and mineral composition typical of suggesting a supergene origin. Chalcedonic quartz, kaolinite, illite, goethite and hematite are constituting a characteristic authigenic mineral assemblage and, in places, smectite is less commonly included in the weathering product. In addition to these authigenic phases, some detrital minerals such as mica and orthoclase constituting relatively coarser grains are also rarely present in the supergene alterations. A rather complex clay facies consisting of kaolinite, illite and smectite in the alterations seems to correspond to the typical clay composition of the reported residual pedogenic soils by limestone weathering. The cryptocrystalline weathering product is partly altered to stilbite, a characteristic hydrothermal zeolite, in places, by the hydrothermal contact of late stage. The time of formation and infiltration of the supergene alterations seems to correspond to the stage just after the epithermal alteration of the Pungchon Limestone, i. e., an early Jurassic age. The supergene alteration, which may imply the stage of uplifting, weathering and erosion of the Chosun Supergroup, appears to have undergone at an oxygen-rich environment in descending water of meteoric origin by means of a chemical leaching and diffusion.