• 제목/요약/키워드: Oyster shells

검색결과 154건 처리시간 0.022초

디지털이미지를 이용한 폐기물 혼합 콘크리트의 강도 평가 (Evaluation of strength of waste material mixed concrete using digital image)

  • 윤현석;이기호;박준범
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2005년도 춘계 학술발표회 논문집
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    • pp.1390-1395
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    • 2005
  • To analyze the effects of oyster shell particles, inserted in the self-hardening matrix such as cement paste, on strength, homogenization analysis using micro structure was used to estimate and assess the apparent elastic modulus of oyster shell particle. DIB modeling technique was used to represent of the micro structure of oyster shell mixed concrete. The results showed that the apparent elastic modulus of LOS (large oyster shell particle) was changed with the amount of LOS inserted. In particular, when the amount of LOS was 200% of the weight of cement, the apparent elastic modulus of LOS tended to decrease rapidly. This could mean that the strength of oyster shell mixed concrete is much affected by LOS inserted material in mixed ratio of 200%.

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모래다짐말뚝(SCP) 지반개량을 위한 굴패각-모래 혼합토 실험연구 (Experiments of Oyster-shell Mixed with Sand for Sand Compaction Pile)

  • 윤길림;윤여원;채광석;안영천
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2004년도 춘계학술발표회
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    • pp.162-169
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    • 2004
  • In order to investigate a recycling possibility as a construction material of oyster-shells, the geotechnical characteristics including N-value, confined compression and shear strength for oyster shell mixed soils were quantitatively examined. Experimental results show that the oyster shell mixed soils are lighter than sand in weight, and have similar characteristics of shear strength with sandy soils. Based on the experimental results, it is highly judged that crushed oyster-shell can be a substitute of sand as the SCP method.

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굴패각 및 고로슬래그 산업부산물을 재활용한 콘크리트 투수블록의 제조에 대한 실험적 연구 (An Experimental Study on Manufacturing Permeable Concrete Blocks from Recycled Industrial By-Products of Oyster Shell and Blast Furnace Slag)

  • 어석홍;허원석;하상훈;이창열
    • 한국산업융합학회 논문집
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    • 제26권6_2호
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    • pp.1135-1144
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    • 2023
  • In this paper, bending strength and permeability tests were conducted on concrete permeable blocks manufactured by recycling industrial by-products of oyster shell and blast furnace slag to measure and compare bending strength and permeability coefficient, and present experimental research results. To this end, a total of 54 specimens with a size of 200x200x60mm for surface layer and base layer were manufactured, and bending strength and permeability test were carried ourt accoridng to KS F 4419. Eighteen types of mixing designs were implemented by varying the mixing and replacement rates of oyster shells and blast furnace slag. As a result of the experiment, the higher the mixing ratio of oyster shell, the lower the bending strength and the permeability coefficient. Thereafter, a total of three permeable blocks with dimensions of 200x200x60mm were manufactured and subjected to bending strength and permeability tests according to KS F 4419. As a result of the test, the bending strength satisfies the standard of KS F 4419, and the permeability coefficient is 12 times higher than the standard of KS F 4419. It seems that the proper mixing of oyster shells and blast furnace slag increases the amount of air, and further research on durability and economic feasibility of materials used to manufacture permeable blocks is required.

굴 패각의 소성 조건에 따른 소석회의 특성과 외부용 수성 도료 적용 연구 (A Study on the Characteristics of Ca(OH)2 According to the Calcination Conditions of Oyster Shells and Its Application for Exterior Water Paints)

  • 황대주;유영환;한창수;이종대
    • Korean Chemical Engineering Research
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    • 제60권4호
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    • pp.594-605
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    • 2022
  • 마이크로웨이브 소성로를 이용하여 굴 패각을 소성하여 CaO 제조하였다. 제조된 CaO를 수화 반응시켜서 Ca(OH)2를 분석하였다. 합성한 Ca(OH)2를 주성분으로하여 외부용 수성 도료 배합하였다. 굴 패각(325 mesh, 43 ㎛)은 (a) 950 ℃/1 시간와 (b) 1,150 ℃/1 시간 동안 탈탄산화반응을 시켜 CaO를 제조하였다. (a)의 소성 조건에서는 CaO 56.7 wt%이고 (b)의 소성 조건에서는 CaO 100 wt%였다. 굴 패각의 소성에 의한 CaO를 석회석의 경우와 비교하기 위하여 석회석(25~30 mm)을 950 ℃/1 시간 동안 탈탄산화 반응시켜서 CaO를 제조하였으며, XRD 분석 결과 CaO 100 wt%로 분석 되었다. 굴 패각의 소성 조건인 (b) 1,150 ℃, 1시간으로 CaO를 제조하여 수화 반응을 통하여 Ca(OH)2를 합성하였다. 제조된 CaO의 수화 조건은 (a) CaO : H2O(100 g : 200 g)과 (b) CaO : H2O(100 g : 400 g)로 수화 반응성을 실시하였다. 수화 반응 결과, 저 반응성으로 확인 되었다. 100 wt%의 Ca(OH)2를 합성하였다. 특히 (a)의 수화 조건에서 합성한 Ca(OH)2는 판상형으로 분석되었다. 굴 패각으로 합성한 Ca(OH)2를 주성분으로 외부용 수성 도료를 배합하였다. 외부용 수성 도료 표준 규격(KS M 6010)의 15개 항목에 대하여 분석하였을 때 냉동안정성을 제외한 다른 모든 기준에 적합한 것을 확인하였다.

Extraction of Precipitated Calcium Carbonate from Oyster Shell waste and Its Applications

  • Ramakrishna, Chilakala;Thenepalli, Thriveni;Nam, Seong Young;Kim, Chunsik;Ahn, Ji Whan
    • 에너지공학
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    • 제27권1호
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    • pp.51-58
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    • 2018
  • In this paper, we reported that the influence of advanced functional mineral filler calcium carbonate ($CaCO_3$) extracted from oyster shell waste, which are rich mineral sources of $CaCO_3$. Oyster Shells, available in abundance, have no eminent use and are commonly regarded as waste. Their improper disposal causes a significant level of environmental concern and also results in a waste of natural resources. Recycling shell waste could potentially eliminate the disposal problem, and also turn an otherwise useless waste into high value added products. Oyster shell waste calcination process to produce pure lime (CaO) which have good anti-microbial property for waste water treatment and then focuses on its current applications to treat the coffee waste and its effluents for biological treatment and utilization as a fertilizers.

굴 패각으로부터 제조된 수산화아파타이트 분말 특성에 관한 연구 (A Study on the Properties of Hydroxyapatite Powders Prepared from Oyster Shells)

  • 류수착;김혜성
    • 한국재료학회지
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    • 제13권11호
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    • pp.703-707
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    • 2003
  • Hydroxyapatite powders were prepared by oyster shells and phosphoric acid. They were heat treated at the $1300^{\circ}C$ for 2 hrs. Only hydroxyapatite phases were observed by the XRD analysis. XRF confirmed that the prepared hydroxyapatite composed with 63.2wt% CaO and 35.7wt% $P_2$$O_{5}$ . In the ICP test, small amount of heavy metals were detected as low as 0.009 ppm Ti and 0.002 ppm Ba. The test of bone density was done in human body during three months. As the periods of medication progressed, the bone density was increased.

굴패각을 포함한 혼합토의 전단.변형 특성 평가를 위한 균질화법의 적용 (Application of the Homogenization Method for Estimation of the Shear Characteristics in Composite Soil Including an Oyster Shells)

  • 이기호;박준범
    • 한국지반공학회논문집
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    • 제17권4호
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    • pp.183-190
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    • 2001
  • 굴패각을 혼합한 해성점토를 매립재료로 활용하기 위한 기초 자료를 얻기 위해, 혼합토의 전단.변형특성을 검토했다. 또한 삼축압축실험과 균질화이론을 근거로 한 수치해석에 의해 혼합재(굴패각)의 겉보기 탄성계수를 구하기 위한 방법을 제안했다. 일련의 실험결과로부터, 굴패각의 혼합에 의해 점토의 전단.변형특성이 개선됨을 확인했고, 굴패각의 겉보기 탄성계수를 구하기 위해 미시구조를 검토할 수 있는 균질화법을 도입했다. 굴패각의 겉보기 탄성계수는 굴패각의 골격구조의 변화에 기인해 변화하고 선행압밀응력이 작은 경우에 그 영향이 크게 나타나는 것을 알 수 있었다.

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전통 호분 제조기술 연구 - 풍화방법을 중심으로 - (Investigation of the Korean Traditional Hobun Manufacturing Technique - Centering on Weathering Method -)

  • 김순관;이한형;김호정;정혜영
    • 보존과학연구
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    • 통권29호
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    • pp.199-220
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    • 2008
  • Hobun(Oyster shell White) is a traditional material used as extender and white pigment from ancient times. The production method of it, however, has been discontinued. We have studied the traditional production method of Hobun by weathering oyster shell, which is one of the traditional ways for preparing Hobun. Reproduction study of manufacturing method of the discontinued traditional material is an important accomplishment of our research. Also this study provides solid background knowledge to stabilize the production and supply of Hobun for the cultural asset repairing materials. The result can be summarized as follows: The production process of Hobun by weathering method takes 5 steps - (1) weathering shells ${\rightarrow}$ (2) washing ${\rightarrow}$ (3) pulverization ${\rightarrow}$ (4) separating fine powder by submerging in water ${\rightarrow}$ (5) drying. The major aim in step (1) is to eliminate organic impurities. In the step (4), the fine particles smaller than $25{\mu}m$ are separated by extracting the supernatant from stirred suspension after heavy particles are submerged. Also, the soluble inorganic impurities can be eliminated through the powder submerge in 15 times water and stirring the suspension 6 hours and changing the water 3~4 times. The final products have high quality with 94.03, 0.52, 2.05 for L, a, b, less than $25{\mu}m$ particle size, fine resistance for discoloration by light and environmental pollution and good workability.

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굴 패각을 사용한 경량기포 콘크리트의 단위시멘트량에 따른 물리적 성능에 관한 연구 (Study on physical performance of lightweight foam concrete using oyster shells according to unit cement content)

  • 홍상훈;신종현;신동욱;김봉주;정의인
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2020년도 봄 학술논문 발표대회
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    • pp.102-103
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    • 2020
  • Research for heat insulation of buildings is being carried out, in which a heat exchange barrier is used around the openings and balcony parts as a method for heat exchange blocks. However, the preparation for a fire is inadequate. In order to improve the EPS used as a heat exchange barrier in an attempt to solve this, there is a study on lightweight foamed concrete, but as the amount of EPS used for strengthening fire resistance increases, it becomes lower. There is no strength applied to buildings, and also. There is a limit to the amount of EPS used. In the study, we use oyster shells to secure the EPS replacement rate limit of lightweight Foamed concrete, and try to measure the change of physical properties depending on the unit cement content.

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Anti-inflammatory Effect of Oyster Shell Extract in LPS-stimulated Raw 264.7 Cells

  • Lee, Se-Young;Kim, Hak-Ju;Han, Ji-Sook
    • Preventive Nutrition and Food Science
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    • 제18권1호
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    • pp.23-29
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    • 2013
  • This study was designed to investigate the anti-inflammatory effect of oyster shell extract on the production of pro-inflammatory factors [NO, reactive oxygen species (ROS), nuclear factor-kappa B (NF-${\kappa}B$), inducible nitric oxide synthase (iNOS) and cycloxygenase-2 (COX-2)] and pro-inflammatory cytokines [Interleukin-$1{\beta}$ (IL-$1{\beta}$), Interleukin-6 (IL-6) and TNF-${\alpha}$] in the lipopolysaccharide (LPS)-stimulated Raw 264.7 cells. Cell viability, as measured by the MTT assay, showed that oyster shell extract had no significant cytotoxicity in Raw 264.7 cells. The treatment with oyster shell extract decreased the generation of intracellular reactive oxygen species dose dependently and increased antioxidant enzyme activities, such as SOD, catalase, GSH-px in LPS-stimulated macrophage cells. Oyster shell extract significantly suppressed the production of NO and also decreased the expressions of iNOS, COX-2 and NF-${\kappa}B$. Additionally, oyster shell extract significantly inhibited the production of IL-$1{\beta}$, IL-6, and TNF-${\alpha}$ in LPS-stimulated Raw 264.7 cells. Thus, these results showed that the oyster shell extract had an anti-inflammatory effect on LPS-stimulated Raw 264.7 cells.