채광석 Kwang-seok Chea , 이영근 Lee Young Geun , 구남인 Namin Koo , 윤호중 Hojoong Youn , 임종환 Lim Jong-hwan

DOI: Vol.35(No.1) 1-12, 2022

Stone has been used for various purposes, such as for building stones, megaliths, ornamental stones, hunting and grinding throughout history. The global stone production amounted to around 153 million tons in 2018 excluding quarry waste, up 0.8% on year. Of them, stone residues accounted for 71%. The worldwide stone trading decreased 1.5 million tons to 56.5 million tons in 2018. The average price of stone was 34.1 USD per square meter, down 2.5% from the previous year. It’s down 7% when only considering trading between the world’s top twelve exporters. But in the three leading countries, Italy, Greece and Brazil, the price saw a sharp increase. In 2018, stone imports and exports totaled 815 million square meters, raising over 20 billion USD of revenue. Imports were largely led by six countries: China, Italy, Turkey, India, Brazil, Spain and Portugal, from largest to smallest.) In terms of stone use per 1,000 population, it was 117 square meters in 2001, and it increased to 264 square meters in 2017 and 266 square meters in 2018. The volume more than doubled during the period, but it has been declining slightly in recent years. China, India, Saudi Arabia and Belgium were the only countries that the stone use per 1,000 population exceeded 1,000 square meters. The increase rate was steepest in China, India and the United States, from largest to smallest. The global stone production is likely to grow to 69.85 million tons by 2025, despite the global economic downturn.

석재, 수입, 수출, 부산물, 동향, Stone, Export, Import, Residue, Trends

구효진 Hyo Jin Koo , 임기택 Gi Taek Lim , 조현구 Hyen Goo Cho

DOI: Vol.35(No.1) 13-24, 2022

The Arctic Ocean is very sensitive to global warming and Arctic Ocean sediments provide a records of terrestrial climate change, analyzing their composition helps clarify global warming. The gravity core sediment ARA07C-St02B was collected at the East Siberian margin during an Arctic expedition in 2016 on the Korean ice-breaking vessel ARAON, and its provenance was estimated through sedimentological, mineralogical and geochemical analysis. The core sediment was divided into four units based on sediment color, sand content and ice-rafted debris content. Units 1 and 3 had higher sand and ice-rafted debris contents than units 2 and 4, and contained a brown layer, whereas units 2 and 4 were mainly composed of a gray layer. Correlation analysis using the adjacent core sediment ARA03B-27 suggested that the sediment units were deposited during marine isotope stage 1 to 4. The bulk mineral, clay mineral, and geochemical compositions of units including a brown layer differed from units including a gray layer. Bulk and clay mineral compositions indicated that coarse and fine sediments had a different origin. Coarse sediments might have been deposited mostly by the East Siberian Coastal Current from the Laptev Sea and the East Siberian Sea or by the Beaufort Gyre from the Chukchi Sea, whereas fine sediments might have been transpoted mostly by currents from the East Siberian Sea, the Chukchi Sea and the Beaufort Sea. Some of the coarse sediments in unit 1 and fine sediments in unit 3 might have been deposited by iceberg ice, sea ice or current from the Beaufort Sea and the Canada Archipelago. Investigating the geochemical composition of the potential origins will elucidate the origin and transportation of the study area’s core sediments.

동시베리아해 연변부, ARA07C-St02B 중력 코어, 갈색층, 회색층, 빙운쇄설물, 동시베리아 연안류, 기원지, East siberian margin, ARA07C-St02B gravity core, Brown layer, Gray layer, Ice rafted debris, East Siberian coastal current, Sediment provenance

전지훈 Ji-hun Jeon , 이종환 Jong-hwan Lee , 이우춘 Woo-chun Lee , 이상우 Sang-woo Lee , 김순오 Soon-oh Kim

DOI: Vol.35(No.1) 25-39, 2022

This study was conducted to evaluate the manufacturing process of non-sintered cement for the safe containment of radioactive waste using low level or ultra-low level radioactive waste soil generated from nuclear-decommissioning facilities, clay minerals, and blast furnace slag (BFS) as an industrial byproduct recycling and to characterize the products using mineralogical and morphological analyses. A stepwise approach was used: (1) measuring properties of source materials (reactants), such as waste soil, clay minerals, and BFS, (2) manufacturing the non-sintered cement for the containment of radioactive waste using source materials and deducing the optimal mixing ratio of solidifying and adjusting agents, and (3) conducting mineralogical and morphological analyses of products from the hydration reactions of manufactured nonsintered cement solidifier (NSCS) containing waste concrete generated from nuclear-decommissioning facilities. The analytical results of NSCS using waste soil and clay minerals confirmed none of the hydration products, but calcium silicate (CSH) and ettringite were examined as hydration products in the case of using BFS. The compressive strength of NSCS manufactured with the optimum mixing ratio and using waste soil and clay minerals was 3 MPa after the 28-day curing period, and it was not satisfied with the acceptance criteria (3.44 MPa) for being brought in disposal sites. However, the compressive strength of NSCS using BFS was estimated to be satisfied with the acceptance criteria, despite manufacturing conditions, and it was maximized to 27 MPa at the optimal mixing ratio. The results indicate that the most relevant NSCS for the safe containment of radioactive waste can be manufactured using BFS as solidifying agent and using waste soil and clay minerals as adsorbents for radioactive nuclides.

원전해체 시설, 방사성 폐기물, 비소성 시멘트, 고화체, 고화재, Nuclear-decommissioning facilities, Radioactive waste, Non-sintered cement, Solidifier, Solidifying agent

김후식 Hu Sik Kim , 박종삼 Jong Sam Park , 임우택 Woo Taik Lim

DOI: Vol.35(No.1) 41-50, 2022

Abstract: To study the properties of Sr₂₊ exchange into zeolite A with increasing the molar concentration of Na₊ in given exchange solution, four single crystals of fully dehydrated Sr₂₊- and Na₊- exchanged zeolite A were prepared by the bath method using mixed ion-exchange solutions. The Sr(NO₃)₂:NaNO₃molar rations of the ion exchange solution were 1:1(crystal 1), 1:100(crystal 2), 1:250(crystal 3), and 1:500 (crystal 4), respectively, with a total concentration of 0.05 M. The single-crystals were then vacuum dehydration at 623 K and 1×10_-4 Pa for 2 days. Their single-crystal structures were determined by single-crystal synchrotron X-ray diffraction techniques in the cubic space group Pm3-m, at 100(1) K, and were then refined to the final error indices of R₁/wR₂=0.047/0.146, 0.048/0.142, 0.036/0.128, and 0.040/0.156 for crystals 1, 2, 3, and 4, respectively. In crystals 1 and 2, the 6 Sr₂₊ ions are found at three different crystallographic sites. In crystal 3, 1 Sr₂₊ and 10 Na₊ ions are found in large cavity and sodalite unit. In crystal 4, only 12 Na₊ ions occupy three equipoints. The degree of Sr₂₊ ion-exchange decreased sharply from 100 to 16.7 to 0% as the initial Na₊ concentration increase and the Sr₂₊ concentration decrease. In addition, the unit cell constant of the zeolite framework decreased with this lower level of Sr₂₊ exchange.

제올라이트 A, 이온교환, 스트론튬 이온, 소듐 이온, 결정학, Zeolite A, Ion exchange, Sr_{2+, Na+, Crystallography}

도진영 Jin Young Do

DOI: Vol.35(No.1) 51-64, 2022

For effective preservation of the rocks, which bearing plant fossils at Gumkwangdong Formation, Pohang, the properties of rock and treatment of chemicals were examined in an artificial weathering test. The rocks are diatomaceous siliceous mudstone, which contain a small amount of smectite and has developed laminated layers. The rocks react with water, the d001 spacing of smectite was increased. On the one hand, the physical properties of the rock samples, such as surface hardness, improved after the application of ethyl silicate-based stone strengthener. On the other hand, the spacing of interlayer of swelling clay minerals decreased and spacing of laminae layer increased. When the ethyl silicate-based stone strengthener was applied after pretreatment with a swelling inhibitor, interlayer and spacing of laminae changes were similar to those when only the stone strengthener was treated. The effect of the swelling inhibitor was almost negligible. When the rocks that have been conserved with chemicals react with water, spacing of laminae has widened much, whereas when the rocks was in contact with moisture only, there was little change. In addition, if it is placed in the outdoor after conservation treatment, although it occurs slightly slower than the untreated rock, the separation of the lamination layer and the pulverization of the rock occur within a very short time. Consolidation is required to improve the physical properties of fossil rock, but when exposed to rain and undergoing freeze-thaw process, the effect is lost very quickly. Therefore, regardless of the chemical treatment, it is a priority to prevent direct rainfall contact with the rock.

규조토성 규질이암, 엽층리, 화석산지, 팽윤성 점토광물, 강화제, 팽윤저지제, Diatomaceous siliceous mudstone, Lamination, Fossil site, Swelling clay mineral, Consolidant, Swelling inhibitor

이주호 Juho Lhee , 김용현 Yong-hyun Kim , 이아침 A Chim Lee , 김은정 Eun Jeong Kim , 이서영 Seoyoung Lee , 이성근 Sung Keun Lee

DOI: Vol.35(No.1) 65-73, 2022

The proper estimation of physical and chemical properties of Earth materials and their structures at high pressure and high temperature conditions is key to the full understanding of diverse geological processes in Earth and planetary interiors. Multi-anvil press - high-pressure generating device - provides unique information of Earth materials under compression, mainly relevant to Earth’s upper mantle. The quantitative estimation of the relationship between the oil load within press and the actual pressure conditions within the sample needs to be established to infer the planetary processes. Such pressure-load calibration has often been based on the phase transitions of crystalline earth materials with known pressure conditions; however, unlike at high temperature conditions, phase transitions at low (or room) temperatures can be sluggish, making the calibration at such conditions challenging. In this study, we explored the changes in Al coordination environments of permanently densified pyrope glasses upon the cold compression using the high-resolution ²⁷Al MAS and 3QMAS NMR. The fractions of highly coordinated Al in the cold compressed pyrope glasses increase with increasing oil load and thus, the peak pressure condition. Based on known relationship between the peak pressure and the Al coordination environment in the compressed pyrope glasses at room temperature, we established a room temperature pressure-load calibration of the 14/8 HT assembly in 1,100-ton multi-anvil press. The current results highlight the first pressure-load calibration of any high pressure device using high-resolution NMR. Irreversible structural densification upon cold compression observed for the pyrope glasses provides insights into the deformation and densification mechanisms of amorphous earth materials at low temperature and high pressure conditions within the subducting slabs.

비정질 파이로프, ^{27Al MAS & 3QMAS NMR, 알루미늄 배위 환경, 멀티 앤빌 프레스, 상온 압력-부하 보정, Pyrope glass, 27Al MAS & 3QMAS NMR, Al coordination environment, Multi-anvil press, Room temperature pressure-load calibration}

김성용 Seong-yong Kim , 허철호 Chul-ho Heo

DOI: Vol.35(No.1) 75-81, 2022

Given that China’s resource research, exploration and development and resource economy policies are closely related to Korea’s industrial competitiveness in the field of global mineral energy resources, it is important to establish the domestic and overseas resource development strategies. In 2020, China will revise and set standards for mineral resources to ensure efficiency in exploration and development and storage management. China’s Ministry of Natural Resources has established the National Mineral Resources Plan (2021-2025), aiming to achieve national goals and strategies, and local governments at all levels are also establishing and implementing regional mineral resources plans. As a result, the supervision and management of geological mineral exploration activities have been strengthened, and the safety of industrial production management in the field of geological mineral exploration and development has been strengthened. China has developed guidelines for high-quality geological exploration, surveying and mapping, improved the level of geological mineral exploration and strengthened the mining supervision and management system. According to China’s standardization of mineral resources such as solid mineral resources and petroleum gas mineral resources, a new standard system for resource management will be established in China to improve scientific understanding, rational management and utilization.

중국, 광물자원, 탐사개발, 매장량, China, mineral resources, Exploration and mining, Reserves