• 한국환경과학회지
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• 제30권10호
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• pp.803-809
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• 2021

This study aimed to investigate the effects of soil amendment (heat-expanded clay and active carbon) and planting of Dendranthema zawadskii var. latilobum on the remediation of salt-affected soil and the plant growth under high calcium chloride (CaCl₂) concentration. The experimental group comprised treatments including Non treatment (Cont.), heat-expanded clay (H), active carbon (AC), planting (P), heat-expanded clay+planting (H+P), active carbon+planting (AC+P). A 200 mL solution of CaCl₂ at a concentration of 10 g·L^-1 was applied as irrigation once every 2 weeks. Compared to the Cont., the incorporation of the 'heat-expanded clay' amendment decreased electrical conductivity of the soil leachate and cation exchange capacity, whereas the growth of Dendranthema zawadskii var. latilobum was relatively increased. These results suggest that the combination of 'heat-expanded clay' amendment and planting will mitigate negative effect of de-icing salts and improve plant growth in salt-contaminated roadside soils.

• 한국환경과학회지
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• 제7권3호
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• pp.269-274
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• 1998

In order to develop of support medla for bloom reactor, physicochemical properties and attachability of surface of activated carbon, clay mineral, non-clay mineral, and waste mold sand were enamined. Measured physicochemical properties of materials were surface roughness, mean particle size, surface area, hydrophobicity, and surface charge. At a tested materials, activated carbon was the best attachable material and microorganisms were attached $20.1{\times}10^7CFU/cm^2$ at surface, compared with diatomaceous earth which were attached of $9.2{\times}10^7CFU/cm^2$ in our research, surface area and hydrophobicity show- ed more Influence than any other factor on attachment of microorganisms.

• 한국세라믹학회지
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• 제24권5호
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• pp.437-446
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• 1987

In this study the attempts were made to investigate the possibilities of using domestic clay minerals and zeolite, which are available in almost unlimitted quantities, for preparation of aluminum sulfate, white carbon and silica gel. Aluminum sulfate was obtained by the method of sulfuric acid treatment. White carbon and silica gel were prepared by utilizing crystalline silica which was obtained as a by product during preparing the aluminum sulfate. White carbon was obtained by reacting 5.0 weight percent sulfuric acid solution with water glass which was a reaction product of crystalline silica and soldium hydroxide in a autoclave, while silica gel was obtained by reaction 10.0 weight percent acetic acid solution with water glass.

• 한국광물학회지
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• 제17권3호
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• pp.189-199
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• 2004

대전-통영간 35번 고속도로 고성교차로 건설공사현장에서 발견된 공룡발자국화석의 보존 및 전시를 위한 응용광물학적 연구를 실시하였다 백악기 공룡발자국 퇴적암은 흑색점토층과 암회색 실트층의 호층으로 구성되어 있으며, 수평 또는 수직 열극에는 방해석맥이나 표성기원의 산화철 또는 산화망간 침전물이 충전되어 있다. 강물조성은 전반적으로 석영, 앨바이트, K장석, 방해석, 녹니석 일라이트 백운모, 흑운모와 미량의 인회석, 금홍석으로 구성되어 있으며, 방해석과 앨바이드는 실트층, 그리고 석영, 일라이트,녹니석은 점토층에 부화되어 있다. 주원소인 Al, Fe, Mg, K, Ti, P는 절토층, Ca Na Mn은 실트층, 그리고 미랑원소인 V, Cr, Co, Ni, Cs, Zr, REE, Th, U 등은 점토층에 부화되어 있다. 탄소의 경우, 무기탄소는 실트층에 방해석의 형태로 농집되어 있으며, 유기탄소는 흑색점토층에 부화되어 있다. 흑색점토층은 열극을 따라 부분적으로 유기탄소가 이차적으로 산화제거되어 연황색 점토층으로 변질되었다. 점토광물이 풍부한 흑색 및 연황색 점토의 층리를 따른 선택적 박리현상, 실트층의 기질 또는 수직절리의 주요 충전물인 방해석의 용해성과 낮은 강도는 발자국 화석 표본의 향후 물리적, 화학적 훼손을 촉진할 수 있는 잠재적 요소로 평가되었다.

• Carbon letters
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• 제11권4호
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• pp.293-297
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• 2010

To investigate new potential application of a clay material for C/C composites, illite added C/C composites were prepared with various illite contents. The improvement of filler effect by illite size reduction was also investigated using wet ballmilling by evaluating illite/phenolic resin infiltration using bulk density and porosity measurements, chemical structural changes of the composites using XRD, and thermal oxidation stability in air of the composites using TGA. The size reduction of illite resulted in narrower particle size distribution and improved illite infiltration into carbon preform. And the resultant C/C composites prepared with illite had even more improved thermal oxidation stability in air, showing more increased IDTs up to $100^{\circ}C$, compared to those of the C/C composites with pristine illite, due to the SiC formation through carbothermal reduction between illite and carbon materials. The illite induced delay in oxidation of the illite-C/C composites was also observed and the delayed oxidation behavior was attributed to the layered structure of illite, which improved illite/phenol resin infiltration. Therefore, the potential use of illite as filler to improve oxidation stability of C/C composite can be promising. And the size reduction of illite can improve its effect on the desired properties of illite-C/C composites even more.

• 상하수도학회지
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• 제21권1호
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• pp.37-46
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• 2007

A feasibility test was conducted to evaluate the addition of turbidity substance in a coagulation process to remove natural organic matters (NOM), the precursor of disinfection by-products (DBPs). The experimental water sources were synthetic water containing 5 mg/L of humic acid and 50 mg/L of NaHCO3 and drinking water resource of Ulsan city (S Dam water, D Dam water and Nak-Dong raw water). The examined turbidity substances were kaolin, acid clay, and modified clay (0.38 meq $NH_4{^+}-N/g$ clay). In Jar tests at different concentrations of the turbidity substances (5, 10, 15, 20, 30 mg/L) using the synthetic water, the turbidity substances improved the removal of turbidity, UV-254 absorbance and dissolved organic carbon (DOC) by 23.8-38.1%, 17.0-24.5% and 2.5-44.5%, respectively. The modified clay showed higher removal efficiencies than other substances. In Jar tests using the drinking water, 10 and 20 mg/L of modified clay enhanced the removal efficiencies of turbidity, UV-254 absorbance, DOC, trihalomethane formation potential (THMFP), and haloacetic acid formation potential (HAAFP) by 3.0~4.3%, 19.1~29.0%, 12~34.9%, 4.9~36.7%, and 1.6~30.2%, respectively.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2020년도 봄 학술논문 발표대회
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• pp.189-190
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• 2020

The importance of indoor air quality management has recently been highlighted due to environmental problems such as indoor air pollution. Among indoor air pollutants, carbon dioxide occurs in cooking, heating, burning, and causes forgetfulness, dementia and amnesia. Radon, which occurs in building materials, soil and ground, is a type 1 carcinogen that causes lung cancer in the body through breathing. These substances can be released from the room through ventilation, but there is a limit to reducing the amount of indoor activity due to reduced ventilation conditions due to increased indoor activity time. However, these substances can be removed from the gas by adsorption. The purpose of this study was to identify the properties of granular active and powdered active white soil and mix them to make cement-based active white soil adsorbent matrix for carbon dioxide, fine dust and radon gas adsorption, and to evaluate indoor air improvements according to the mixing scale. The results of the experiment showed that active carbon dioxide adsorption performance increased for carbon dioxide and radon as the exchange rate increased through physical adsorption. In particular, the higher the replacement rate of the granular active bag, the better adsorption performance was shown.

• 한국지구과학회지
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• 제33권4호
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• pp.320-328
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• 2012

후기 홀로세 동안의 지형발달과 기후환경변화를 고찰하기 위해 함평천 유역의 충적평야에서 채취된 퇴적물 시료에 대한 탄소연대측정(AMS, Accelerated Mass Spectrometry), 토양유기탄소와 휴무스분석을 실시하였다. 최하부인 토탄층은 온난 습윤한 기후환경에 형성되었으며, 후빙기 중 Atlantic기에 해당되는 것으로 사료된다. 황갈색 사질점토층은 자연제방성 퇴적물이며, 대체로 온난하고 건조한 기후 환경에서 퇴적된 것으로 생각된다. 그 형성시기는 1,879-1,532 BC 이며, 이 시기는 후빙기 중 Sub-boreal기에 해당된다. 담갈색 점토층은 자연제방에서 배후습지로 이행되는 환경에 퇴적되었을 것으로 추측된다. 기후 환경은 온난하고 습윤하였으며, 후빙기 중 Sub-boreal에서 Sub-Atlantic으로 이행되는 시기에 형성된 것으로 유추된다. 상부의 담황갈색 점토층과 담갈색 점토층은 배후습지의 퇴적물로 생각된다. 담황갈색 점토층이 퇴적된 환경은 냉량하고 습윤한 기후환경이었을 것으로 생각되며, 이 시기는 후빙기 중 Sub-Atlantic에 대비될 가능성이 있다. 담갈색 점토층이 퇴적된 환경은 온난하고 건조한 기후환경이었을 것으로 생각된다. 그 형성 시기는 211-427 AD이며, 이 시기는 Post Roman Warm Period에 해당되는 것으로 유추된다.

• Geomechanics and Engineering
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• 제4권4호
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• pp.281-294
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• 2012

Filtration using granular media such as quarried sand, anthracite and granular activated carbon is a well-known technique used in both water and wastewater treatment. A relatively new pre-filtration method called pebble matrix filtration (PMF) technology has been proved effective in treating high turbidity water during heavy rain periods that occur in many parts of the world. Sand and pebbles are the principal filter media used in PMF laboratory and pilot field trials conducted in the UK, Papua New Guinea and Serbia. However during first full-scale trials at a water treatment plant in Sri Lanka in 2008, problems were encountered in sourcing the required uniform size and shape of pebbles due to cost, scarcity and Government regulations on pebble dredging. As an alternative to pebbles, hand-made clay pebbles (balls) were fired in a kiln and their performance evaluated for the sustainability of the PMF system. These clay balls within a filter bed are subjected to stresses due to self-weight and overburden, therefore, it is important that clay balls should be able to withstand these stresses in water saturated conditions. In this paper, experimentally determined physical properties including compression failure load (Uniaxial Compressive Strength) and tensile strength at failure (theoretical) of hand-made clay balls are described. Hand-made clay balls fired between the kiln temperatures of $875^{\circ}C$ to $960^{\circ}C$ gave failure loads of between 3.0 kN and 7.1 kN. In another test when clay balls were fired to $1250^{\circ}C$ the failure load was 35.0 kN compared to natural Scottish cobbles with an average failure load of 29.5 kN. The uniaxial compressive strength of clay balls obtained by experiment has been presented in terms of the tensile yield stress of clay balls. Based on the effective stress principle in soil mechanics, a method for the estimation of maximum theoretical load on clay balls used as filter media is proposed and compared with experimental failure loads.

• KSBB Journal
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• 제15권2호
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• pp.201-207
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• 2000

전통적으로 사용되어 왔던 점토의 숙성과정을 과학적으로 규명하였고, 철환원세균의 농화배양액을 이용하는 생명공학기술을 이용한 개량된 점토 숙성방법을 연구하였다. 전통적으로 사용되어 왔던 수비법에 의한 점토의 숙성은 토착 미생물들이 점토에 함유된 유기물을 분해하는 과정에서 철불순물을 점토로부터 제거하여 색상을 향상시킬 뿐만 아니라 점토의 점성과 가소성 및 강도를 증진시키는 효과가 있음을 알 수 있었다. 점토숙성용 철환원세균 농화배양액을 얻는 방법을 제시하였고, 점토에 탄소원을 첨가한 후 혐기적 조건에서 농화배양액을 이용한 점토 숙성 방법을 제시하였다. 생물공학기술을 활용한 개량점토 숙성법은 전통적인 점토 숙성에서 소요되는 점토의 처리 시간을 약 1/6 수준이하로 단축시킬 수 있었고, 점토로부터 철불순물을 보다 효과적으로 제거할 수 있었을 뿐만 아니라 전통적인 방법보다도 물성이 우수한 점토로 고품위화가 가능하였다.