• Proceedings of the Korean Institute of Building Construction Conference
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• 2022.04a
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• pp.166-167
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• 2022

The International Energy Agency(IEA) recommends that intergovernmental agreements reduce CO2 emissions by 2050 to about 50% in 2005 in its report. To realize these demands, it is suggested to actively utilize energy efficiency improvement technology, renewable energy, nuclear power, carbon dioxide capture & storage technology (CCS). In the field of building materials and cement, mineral carbonization technology is widely used. Inorganic by-products applicable to greenhouse gas storage include waste concrete, slag, coal ash, and gypsum. If the Mineral Carbonation Act is used, it is expected that about 12 million tons of greenhouse gases can be immobilized every year. Greenhouse gas immobilization using cement hydrate can be immobilized by injecting carbon dioxide into the hydrated products C-S-H, and Ca(OH)2. In the case of immobilization through concrete carbonization, a carbon dioxide promotion test is used, which is often different from the actual carbon dioxide carbonization reaction. If the external carbon dioxide concentration is abnormally higher than the reality, it is thought that it will be different from the actual reaction. In this study, the carbonation phenomenon according to the concentration and identification of the carbon dioxide reaction mechanism of cement hydrate was to be considered.

• Economic and Environmental Geology
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• v.37 no.1
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• pp.1-19
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• 2004

Metallic deposits in Korea have a variety of genetic types such as hydrothermal veins, skarns, hydrothermal replacement and alaskite deposits and so on. Geological, mineralogical and geochemical features including host rock, wall-rock alteration, ore and gangue mineralogy, mineral texture and secondary mineralogy related to weathering process control the environmental signatures of mining areas. The environmental signatures of metallic deposits closed from early 1970s to late 1990s in Korea show complicate geochemistry and mineralogy due to step weathering of primary and secondary minerals such as oxidation-precipitation-remobilization. The potentiality of low pH and high heavy metal Concentration s from acid mine drainage is great in base-metal deposits associated with polymetallic mineralization, breccia-pipe type and Cretaceous hydrothermal Au veins with the amount of pyrite whereas skam, hydrothermal replacement, hydrothermal Cu and Au-Ag vein deposits are in low contamination possibility. The geoenvironmental models reflecting the various geologic features closely relate to disuibution of sulfides and carbonates and their ratios and finally effect on characteristics of environmental signatures such as heavy metal species and their concentrations in acid mine drainage.

• Economic and Environmental Geology
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• v.34 no.3
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• pp.243-254
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• 2001

Variation in relative contents of clay minerals was used to genetically interpret depositional environment of the Upper Jurassic Solnhofen limestone. Mineralogical examination of whole rocks and clay fractions indicates that the faule and flinz beds are composed mainly of calcite and quartz with minor amount of clay minerals such as illite, kaolinite, and smectite. Smectite shows a trend of illitization: illite layers increase with increasing of burial depth. With increasing burial depth, relative abundance of kaolinite with quartz and illite increases. This implies that the Solnhofen basin was formed during the transgression based on reduce of terrigenous influx.

• Economic and Environmental Geology
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• v.51 no.4
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• pp.323-343
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• 2018

This study defines the mineralogical, micro-textural and geochemical characteristics for the carbonate rocks and discusses the fluids that have affected the depositional environment of the Lower Makgol Formation in Seokgaejae section. Based on analysis of X-ray Diffraction (XRD), Scanning Electron Microscope-Energy Dispersive X-ray Spectrometry (SEM-EDS), Electron Probe Micro Analyzer-Wavelength Dispersive X-ray Spectrometry (EPMA-WDS) and Laser Ablation-Inductively Coupled Plasma-Mass Spectrometry (LA-ICP-MS), carbonate miorofacies in the basal and the lower members of the Makgol Formation are distinguished and classified into four types. Type 1 dolomite (xenotopic interlocking texture) and Type 2 dolomite (idiotopic interlocking texture) have relatively high Mg/Ca ratio, flat REE pattern, low Fe and Mn. Extensively interlocking textures in these dolomites indicate constant supply of Mg ion from hypersaline brine. Type 3 and Type 4 dolomite (scattered and loosely-aggregated texture) have relatively moderate Mg/Ca ratio, MREE enriched pattern, low to high Fe and Mn. These partial dolomitization indicate limited supply of Mg ion under the influx of meteoric water with seawater. Also, the evidence of Fe-bearing minerals, recrystallization and relatively high Fe and Mn in Type 4 indicates the influence of secondary diagenetic fluids under suboxic conditions. Integrating geochemical data with mineralogical and micro-textural evidence, the discrepancy between the basal and the lower members of the Makgol Formation indicates different sedimentary environment. It suggest that hypersaline brine have an influence on the basal member, while mixing meteoric water with seawater have an effect on the lower member of the Makgol Formation.

• Economic and Environmental Geology
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• v.30 no.4
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• pp.289-301
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• 1997

The Boguk cobalt mine is located within the Cretaceous Gyeongsang Sedimentary Basin. Major ore minerals including cobalt-bearing minerals (loellingite, cobaltite, and glaucodot) and Co-bearing arsenopyrite occur together with base-metal sulfides (pyrrhotite, chalcopyrite, pyrite, sphalerite, etc.) and minor amounts of oxides (magnetite and hematite) within fracture-filling $quartz{\pm}actinolite{\pm}carbonate$ veins. These veins are developed within an epicrustal micrographic granite stock which intrudes the Konchonri Formation (mainly of shale). Radiometric date of the granite (85.98 Ma) indicates a Late Cretaceous age for granite emplacement and associated cobalt mineralization. The vein mineralogy is relatively complex and changes with time: cobalt-bearing minerals with actinolite, carbonates, and quartz gangues (stages I and II) ${\rightarrow}$ base-metal sulfides, gold, and Fe oxides with quartz gangues (stage III) ${\rightarrow}$ barren carbonates (stages IV and V). The common occurrence of high-temperature minerals (cobalt-bearing minerals, molybdenite and actinolite) with low-temperature minerals (base-metal sulfides, gold and carbonates) in veins indicates a xenothermal condition of the hydrothermal mineralization. High enrichment of Co in the granite (avg. 50.90 ppm) indicates the magmatic hydrothermal derivation of cobalt from this cooling granite stock, whereas higher amounts of Cu and Zn in the Konchonri Formation shale suggest their derivations largely from shale. The decrease in temperature of hydrothermal fluids with a concomitant increase in fugacity of oxygen with time (for cobalt deposition in stages I and II, $T=560^{\circ}C-390^{\circ}C$ and log $fO_2=$ >-32.7 to -30.7 atm at $350^{\circ}C$; for base-metal sulfide deposition in stage III, $T=380^{\circ}-345^{\circ}C$ and log $fO_2={\geq}-30.7$ atm at $350^{\circ}C$) indicates a transition of the hydrothermal system from a magmatic-water domination toward a less-evolved meteoric-water domination. Sulfur isotope data of stage II sulfide minerals evidence that early, Co-bearing hydrothermal fluids derived originally from an igneous source with a ${\delta}^{34}S_{{\Sigma}S}$ value near 3 to 5‰. The remarkable increase in ${\delta}^{34}S_{H2S}$ values of hydrothermal fluids with time from cobalt deposition in stage II (3-5‰) to base-metal sulfide deposition in stage III (up to about 20‰) also indicates the change of the hydrothermal system toward the meteoric water domination, which resulted in the leaching-out and concentration of isotopically heavier sulfur (sedimentary sulfates), base metals (Cu, Zn, etc.) and gold from surrounding sedimentary rocks during the huge, meteoric water circulation. We suggest that without the formation of the later, meteoric water circulation extensively through surrounding sedimentary rocks the Boguk cobalt deposits would be simple veins only with actinolite + quartz + cobalt-bearing minerals. Furthermore, the formation of the meteoric water circulation after the culmination of a magmatic hydrothermal system resulted in the common occurrence of high-temperature minerals with later, lower-temperature minerals, resulting in a xenothermal feature of the mineralization.

• Proceedings of the Korean Fiber Society Conference
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• 2002.04a
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• pp.313-316
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• 2002

고분자 물질과 유리섬유, 운모, 탄산 칼슘 그리고 점토 광물과 같은 다양한 무기물과의 복합체는 기계적 성질, 열적 성질과 같은 물리적 특성의 향상을 가져올 뿐만 아니라 이와 같은 특성들을 적은 비용으로 향상시킬 수 있는 장점을 가지고 있기 때문에 다양한 방면에서 널리 사용된다[1]. 이에 대해서, 최근 많은 발전을 이루고 있는 나노기술을 고분자와 무기 나노 입자의 복합체에 적용시키는 연구가 활발히 진행되고 있다. (중략)

• Journal of the Mineralogical Society of Korea
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• v.8 no.2
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• pp.91-107
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• 1995

충남 예산-공주-청양지역의 대흥, 평안, 신양(청당)광산에서 산출되는 녹니석에 관하여 화학적 및 성인적 연구를 하였다. 이들 광상은 초염기성암기원의 사문암이 열수변질작용을 받아 생성되었다. 활석 광석의 주 구성 광물은 활석, 녹니석, 금운모, 각섬석류, 사문석, 탄산염광물 등이고 이밖에 감람석, 휘석류, 크롬철석, 스멕타이트, 녹니석/스멕타이트의 혼합층상광물들과 같은 팽윤성 광물들이 소량 산출된다. 이 중 감람석과 크롬철석은 광상의 초염기성암 기원을 지시하는 중요한 광물이다.녹니석은 활석 광석의 불순 광물 중 가장 많은 양을 차지하는 광물이다. 이들 녹니석은 성인적으로 활석과 밀접하게 연관된 녹니석과 그렇지 않은 녹니석의 두 가지 뚜렷한 타입으로 나뉘어지며 이들은 화학적으로 명확한 차이를 보인다. 전자의 녹니석은 Mg/(Mg+Fe)비가 높으며 매우 일정한 범위의 Mg/(Mg+Fe)qkl (0.784∼0.951/산소수 14 기준)를 보여주고, 높은 8면체 치환양 (0.892 (-0.200∼0.692)/산소수 14, 이상적인 클리노클로어/차모사이트 성분 기준)과 넓은 범위의 Al 함량 변화 (2.975 (1.085∼3.160)/산소수 14 기준), 높은 Cr, Ni 함량을 갖는다. 이들은 매우 제한되고 높은 Mg/(Mg+Fe)비를 갖는 환경에서 생성되었으며 따라서,활석과 밀접하게 연관된 녹니석은 생성시, 주변암에 둘러싸여 있는, 초염기성암 기원의 사문암에 의해 주로영향을 받았다. 후자의 녹니석은 전자의 녹니석에 비하여 Fe 함량이 더 놓으며 광범한 범위의 Mg/(Mg+Fe)비 (0.378∼0.852/산소수 14 기준)를 보여주고, 더 적은 범위의 8면체 치환양 (0.560 (-0.035∼0.525)/산소수 14, 이상적인 클리오클로어/차모사이트 성분 기준)과, 전반적으로는 더 높은 값을 가지면서 더 좁은 범위의 Al 함량 변화 (1.491 (1.468∼2.959)/산소수 14 기준)를 보여주며, 낮은 Cr, Ni 함량을 갖는다. 이들은 낮은 Mg/(Mg+Fe)비를 갖고 전자에 비해 Al이 풍부한 환경에서 생성되었으며, 따라서 활석과 연관되지 않은 녹니석은 생성시 광체와 인접한 화강아질 편마암에 의해 주로영향을 받았을 것으로 생각된다. 녹니석의 이러한 2가지 화학조성상의 경향은 녹니석과 공존하는 운모류나 각섬석류들의 화학분석결과와도 잘 일치한다. 이러한 결과는 이 지역의 활석 광상이 초염기성암 기원의 사문암이 열수변질작용을 받아 생성되었음을 명확하게 지시하며, 따라서 활석 광석내에 존재하는 녹니석은 활석의 근원 광물로서 녹니석편암 및 녹니석 편마암 매의 녹니석이 활석화되고 남은 잔존광물이 아니라, 주변암에 의해 성분상의 영향을 받은 열수와 사문암과의 변질교대작용에 의한 활석화과정 중에 주로 생성된 것으로 추정된다. 이러한 결과는 연구지역의 활석광상이 초염기성암의 사문암화 작용과 활석화 작용의 두 가지 변질작용에 의해 형성되어졌음을 알려준다.

• Transactions of the Korean hydrogen and new energy society
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• v.19 no.4
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• pp.340-347
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• 2008

Dissolution process of serpentine in distilled water was systematically investigated for study on pre-treatment of serpentine which was a candidate material for carbon dioxide sequestration. The metallic ions(Ca, Si, Mg etc.) were dissolved in distilled water at ambient condition and their concentrations were changed with dissolution time. The precise evaluation of dissolution process for serpentine dissolved solvent was performed by ion conductivity and pH measurement. Serpentine dissolution in distilled water was evaluated as a stable pre-treatment process without changes of crystallographic structure and chemical structure changes.

• Journal of the Korean Recycled Construction Resources Institute
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• v.9 no.4
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• pp.650-657
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• 2021

Alkali activators that stimulate mineral compounds are expensive materials, but in order to replace industrial products of high alkali in gredien ts, both product an d econ omic feasibility must be satisfied. In this study, alkali in dustrial waste(LW) from the LCD man ufacturin g process were used for the purpose of alkali active reaction of GGBFS for high stren gth concrete over 50MPa. Concrete mixed with LW had reduced workability, but it had the characteristic of increasing compressive strength. Analysis using ACI 209 Compressive Strength Model Equation was made to compare the changes in strength coefficients according to LW mixing. The durability test of concrete, such as Chloride Penetration Resistance and carbonation resistance, also showed excellent performance. In the Adiabatic temperature rise test results, the concrete mixed with LW had the effect of accelerating the initial hydration heat. However, the final Adiabatic temperature rise was not significantly affected by the mixing of LW.

• Applied Chemistry for Engineering
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• v.19 no.5
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• pp.526-532
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• 2008

The proposed $CO_2$ storage technology in the present study is a one-step sequestration process that stabilizes $CO_2$ in a reactor with Serpentine. The advantage of this technology is associated with its high stability of final product so that the entire system is recognized as permanent environment-friendly $CO_2$ removal method. Since the sequestration reaction mechanisms are generally understood that carbonation reaction proceeds with very slow rate, so that pretreatment method to increases reaction rate of $CO_2$ carbonation reaction should be developed. To increase the reactivity of Serpentine with $CO_2$, two different methods of pretreatment are carried out in the present investigation. One is heat-treatment, the other is chemical pretreatment. In this study, only chemical pretreatment is considered leaching method of magnesium from Serpentine using sulfuric acid at the various reaction temperatures, times, and acid concentrations. Experimental results illustrated that pretreatment by sulfuric acid increases surface area of serpentine from $11.1209m^2/g$ to $98.7903m^2/g$ and extracts magnesium compounds. Single variable experiment demonstrated the enhancements of magnesium extraction with increased reaction temperature and time. Amount of magnesium extraction is obtained by using the data of ICP-AES as maximum extraction condition of magnesium is 2 M acid solution, $75^{\circ}C$ and 1hr. After performing chemical pretreatment, carbonation yield increased from 23.24% to 46.30% of weight.