• 자원리싸이클링
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• 제13권3호
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• pp.12-18
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• 2004

불가사리와 조개껍질의 폐 수산자원을 개량제로 이용한 도시하수 슬러지의 탈수능 향상 연구를 수행하였다. 불가사리와 조개껍질을 105∼$700^{\circ}C$로 열처리하여 사용하였으며, 탈수방법으로는 원심분리와 벨트프레스를 사용하였다. 총 고형물 기준으로 개량제를 1∼8g/100mL 주입하여 탈수 후 슬러지 케익의 함수율을 15∼22% 저감시키는 결과를 얻었다. 개량제 주입 후 슬러지의 탈수 특성을 평가하기 위하여 CST(Capillary Suction Time)를 측정하였다. 불가사리 첨가 후 CST는 증가하는 경향을 나타내었으나, 조개껍질 첨가 후 CST는 감소하는 경향을 나타내었다. 조개껍질이 불가사리보다 탈수 효율이 나은 결과를 보였으며, 열처리 온도에 대한 효과는 무시할 수 있을 정도로 적게 나타났다.

• 한국환경과학회지
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• 제11권12호
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• pp.1291-1298
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• 2002

To utilize coastal aquaculture ground bottom sediment in which concentrations of harmful pollutants are low and organic content is high as an organic fertilizer alkaline stabilizers such as CaO, Oyster shell, Mg(OH)$_2$ were added to the bottom sediment organic additives of livestock or food wastes. Nutritive qualities of crude fertilizers were measured to examine effects of alkaline stabilizers and organic waste additions. The Mg(OH)$_2$-added crude fertilizer had significantly lower total carbon(T-C) and nitrogen(T-N) content, reflecting the dilution effect due to great amount of Mg(OH)$_2$ addition. However, the addition of oyster shell had no significant effect on the T-C and T-N content of the fertilizer. $P_2O_5$ and $K_2$O content was considerably higher in the mixed sample of aquaculture ground bottom sediments and livestock wastes than in the mixture of the sediments and food wastes, resulting from higher $P_2O_5$ and $K_2$O content in livestock wastes. Addition of Mg(OH)$_2$ increased the content of MgO In the crude fertilizer but significantly reduced the content of other nutritive elements such as $P_2O_5$, $K_2$O and CaO. Addition of oyster shell as an alkaline stabilizer seemed to have the advantage of saving time and expenses far dryness due to its role as a modulator of water content. Moreover, additions of effect Mg(OH)$_2$ decreased the concentrations of heavy metals in the fertilizer by the dilution while additions of oyster shell had no influence on heavy metal concentrations in the fertilizer.

• Carbon letters
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• 제11권3호
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• pp.169-175
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• 2010

The study describes the results of batch experiments on the removal of Reactive Yellow 15 (RY15) and Reactive Black 5 (RB5) from synthetic textile wastewater onto Activated Carbon from Walnut shell (ACW). The experimental data were analyzed by the Langmuir, Freundlish, Temkin and Dubinin-Radushkevich (D-R) models of adsorption. The experiments were carried out as function of initial concentrations, pH, temperature (303-333), adsorbent dose and kinetics. The surface area and pore volumes of adsorbent were measured by BET and BJH methods. The findings confirm the surface area (BET) is 248.99 $m^2/g$. The data fitted well with the Temkin and D-R isotherms for RY15 and RB5, respectively. The most favorable adsorption occurred in acidic pH. Pseudo-second order kinetic model were best in agreement with adsorption of RY15 and RB5 on ACW. The results indicate that walnut shell could be an alternative to more costly adsorbent currently being used for dyes removal.

• 한국환경보건학회:학술대회논문집
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• 한국환경보건학회 2005년도 국제학술대회
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• pp.365-370
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• 2005

The objective of this study is to develop the sorbent of oyster shell, which can remove gaseous acid pollutants emitted from the incinerator and power plants. The physicochemical properties of prepared absorbents have been measured using ICP and BET Also, this study is to investigate the Hydration/calcination reaction in the fixed bed reactor. Thus, the results could be summarized as follows. Oyster shell can be used in powder type without former processing. It should be also noted that sulfation reactivity of oyster sample increases to about 5 times by calcination/hydration reaction due to the increase of specific surface area and pore volume. From these experiments, we have found that both $SO_2$ and $NO_x$ in simulated flue gas can be effectively removed by use of oyster absorbent.

• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• 제4권3호
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• pp.185-193
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• 2000

A water treatment agent with antimicrobial activity(Ag-Os) was created by exchanging silver ion($Ag^{+}$) on calcined oyster shell powder. The desorption of the exchanged silver ion was negligible, thereby indicating a stable antimicrobial water treatment agent. The sterilization effect of Ag-Os on underwater microorganisms was then investigated. An MIC (Minimum Inhibitory Concentration) test result indicated that Ag-Os had an excellent sterilization effect on G-germs, such as Escherichia coli and Pseudomonas aeruginosa. Most germs were annihilated with an Ag-Os concentration of 200 ppm and contact time of 60 minutes. The sterilization effect was mainly dependent on the contact time. The zeta potential of the Ag-Os powder adsorbed on sand was measured relative to the concentration of exchanged silver ion. As the concentration of the exchanged silver ion increased, the surface charge density of the anions on the surface of the Ag-Os powder adsorbed on sand also increased. Accordingly, this result indicated that a higher silver ion than ion exchange capacity was present on the particle surface due to adsorption. Consequently, this increased concentration of exchanged silver ion would appear to significantly enhance the sterilization power.

• 고문화
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• 61호
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• pp.95-128
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• 2003

패총은 넓은 의미에서 본다면 취락을 구성하는 하나의 구성요소로서 패총에서 출토한 자료의 정보성은 취락인의 생계유형과 방식을 추론할 수 있는 가장 적절한 유적이다. 이 글은 패총이 함유한 여러 정보 가운데에 가장 기본적인 층위에 대하여 살펴보았다. 패총의 층위범주는 인간행위에 의하여 퇴적된 층을 기준으로 패분층, 혼토패층, 패각층, 점토층으로 구분하였다. 다음은 층위의 유형분류로서 평면 및 수직적인 퇴적의 정형성을 알아보기 위해 평면적인 퇴적 유형은 독립 구릉의 비탈진 곳의 여러 장소 퇴적된 점재 I형, 산지에서 연결되는 구릉사면의 몇몇 장소에 분포하는 점재II형, 주거지 주변에 한 개소에 패총이 분포하는 단독형으로 분류하였고, 수직최적 유형은 패총이 형성되는 지표의 모양새에 따라 구지표를 이용한 경우, 선대 유구상면을 이용한 경우, 인위적으로 굴착한 구덩이에 퇴적되는 유형으로 구분하였다. 층위형성은 퇴적물 폐기장소에 따라 달라질 개연성이 높음을 알 수 있고, 그 사례로 층위의 근간을 이루는 패분층, 혼토패층, 패각층, 점토층에 대하여 퇴적물의 구성요소와 형성원인에 대하여 검토하였다. 마지막으로 어떠한 형태의 패총과 규모가 한 지역을 대표할 수 있는가를 알아보기 위하여 김해지역과 창원지역을 비교검토하였는데, 한 지역을 대표할 수 있는 패총의 입지는 구릉 정상부에 위치하여야 하고, 패총 주변에 생산활동과 대내 및 대외 교류가 양호한 지형여건이 갖추어져야 함을 알 수 있었다. 그리고 패총이 점재형으로 형성되어 규모와 조성시점이 장기간이어야 하며, 또한 패총을 포함한 복합유적이어야 한다.

• 한국지반공학회논문집
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• 제18권6호
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• pp.103-116
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• 2002

오염된 부지를 개발하는 경우 유기 화합물로 오염된 부지에 콘크리트 기초가 놓이게 된다. 이러한 경우, 콘크리트 경화는 유기화합물에 영향을 받게 되는데, 본 논문에서는 유기화합물(에틸벤젠)을 혼합한 콘크리트 공시체를 제작하고 일축압축실험을 실시하였다. 콘크리트 공시체 제작 시 골재 대용재료로써 굴패각을 사용하였다. 그 이유는 산업부 산물을 건설재료로 활용하기 위한 가능성을 검토하기 위해서 이다. 또한 굴패각 공시체에 플라이애쉬를 첨가하여 유기화합물의 유무에 따른 강도변화 특성을 고찰하였다.

• Composites Research
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• 제27권5호
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• pp.201-206
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• 2014

Utilizing waste materials in making useful products is a globally increasing trend. This can reduce the cost and environmental issues. In this study, oyster shell powder (OSP) is reinforced as a filler in polypropylene (PP) matrix to make a new composite. The purpose is to improve fire retardant properties of PP as a result of OSP reinforcement. Mechanical, fire retardant and water absorption properties of the new composite have been studied in this research. Concentration of OSP reinforcement in PP has been varied by wt% and its effect on the above mentioned properties has been observed. SEM (scanning electron microscopy) images of tensile and bending fractured surfaces have been taken to observe the failure mechanism during mechanical tests. An increase in the fire retardancy has been observed as a result of the OSP reinforcement while tensile strength decreased. Stiffness also increased with the addition of OSP in PP.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2023년도 봄 학술논문 발표대회
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• pp.51-52
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• 2023

A new shape-stable composite phase change material (PCM) have been produced via an easy and simple vacuum impregnation method. The composite PCM have been derived from almond shell biochar (ASB) as supporting material and capric acid (CA) as phase change material. Cost effective waste almond shells (AS) are renewable, eco-friendly, and rich in pores which enhance the possibility of CA impregnation. Therefore, in this study, three different ratios of CA (1:1, 1:2 and 1:3) have been incorporated in ASB to produce shape-stabilized phase change composites (ASCAs). Different techniques such as scanning electron microscopy (SEM), Fourier transform-infrared spectroscope (FT-IR), differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA) have been applied to evaluate the characteristics of ASCAs. The attained composite PCMs have exhibited shape stability with high latent heat storage, that makes it suitable for thermal energy storage applications.

• Asian-Australasian Journal of Animal Sciences
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• 제12권4호
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• pp.554-557
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• 1999

Hatchery waste including infertile eggs, dead embryos in shell, dead or low grade chicks was cooked at $100^{\circ}C$ for 15 minutes and then oven dried and ground. Hatchery waste meal (HWM) thus prepared contained 44.25% protein, 4,573 kcal/kg gross energy, 3,600 kcal/kg metabolizable energy, 30% ether extract, 1.9% fibre, 14% ash, 9.8% nitrogen free extract, 7.26% Ca, 0.84%P, 1.86% lysine and 0.66% methionine with no Salmonella and E. coli. In biological evaluation trial, significantly higher weight gain was observed in ration containing 12% HWM compared with that containing similar amount of fish meal. Protein efficiency ratio on the two rations was 3.96 vs 2.85; protein digestibility, 86.02 vs 71.9; net protein utilization, 64.9 vs 42.37 and biological value, 75.37 vs 58.84, respectively, indicating better balance of amino acids in HWM compared with fish meal. Growth performance trial on broiler chicks also revealed better weight gain and feed efficiency on ration containing 12% HWM than that containing similar level of fish meal.