• 한국세라믹학회지
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• 제40권3호
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• pp.219-224
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• 2003

Fly ashes containing 6.1~16.5 wt% of unburned carbon were treated thermally at 500$^{\circ}C$ for 3 h and thus, the content of unburned carbon was decreased below 2.1 wt%, the range of particle size distribution became narrower and the mean particle size became smaller. Besides, the properties of particles in fly ashes were improved, particularly the particle shape became close to a spherical type. The fluidity of cement pastes containing fly ashes treated previously at 500$^{\circ}C$ for 3 h was increased much than that of cement pastes containing original fly ashes. When the added amount of superplasticizer was over the saturation amount, there was no correlation between the amount of unburned carbon in fly ashes and the apparent viscosity of cement pastes actually. On the contrary, when the added amount of superplasticizer was below the saturation amount, there was a correlation.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2001년도 총회 및 춘계학술발표회
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• pp.30-33
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• 2001

Melting is one of the most effective treatments for stabilizing heavy metals and also creates high value by-products. In this study, authors evaluated the leaching characteristics of heavy metals in melting slag obtained from incinerator ashes. In order to evaluate the environmental compatibility of the recycled melting slag, the samples analysed various leaching tests of heavy metals were raw incinerator ashes, melting slag and the construction materials recycled from melting slag. As the results: (1) The leaching concentrations of tile melting slag were lower than those of the raw incinerator ashes in the experiment performed in accordance with Korea Standard Leaching Test (KSLT). (2) The result of leaching test with the method of RG Min-StB 93. FGSV Forschungsgesellschaft fur Stra $\beta$ en- und Verkehrswesen) met the requirements in German. (3) The compressive strengths of mortar samples used for evaluating the feasibility of recycling the melting slag as construction materials also showed the suitable range for recycling (4) Melting slag was considered the stable materials with respect to the chemical stability against chemical solutions with various pH conditions.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2000년도 봄 학술발표회 논문집
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• pp.153-158
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• 2000

This study was carried out in order to investigate the relationship roundness of fly ashes and fluidity of fly ash cement paste. electrostatic precipitator system in coal-fired power plant have many successive collection fields in the direction of flue gas travel. In experiment, the roundness of fly ashes collected from the same location had similar values regardless of the load or boiler, and they increased going from the 1st collection filed to third collection filed in the direction of gas movement. In considering the relation between roundness of fly ashes and fluidity of fly ash cement paste, it has a high correlation.

• 한국지반환경공학회 논문집
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• 제4권4호
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• pp.35-43
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• 2003

폐기물로 발생하는 제지슬러지 소각재와 하수슬러지 소각재의 재활용을 위하여 각 소각재의 물리 화학적인 특성을 조사하였으며 소각재가 가지는 포졸란 반응특성을 이용하여 시멘트 혼화재로서 활용가능성에 대하여 검토하였다. 제지 및 하수슬러지 소각재의 입도는 $10{\sim}100{\mu}$에 대부분 분포하고 있으며, 포졸란 반응물질인 $SiO_2$와 $Al_2O_3$의 함량이 45.8~51.0%이였다. 압축강도시험결과 소각재 함량이 10%일 때 비교적 높은 압축강도를 나타났으며 기공율 또한 하수슬러지 소각재를 제외하고 10%일 때 낮은 것으로 나타났다. 이 결과 제지슬러지 소각재의 경우 시멘트 혼화재로써의 재활용 가능성이 충분한 것으로 판단된다.

• 한국대기환경학회지
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• 제16권4호
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• pp.299-308
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• 2000

This study analyzed solid wastes generated from a school. The emission potential of hazardous pollutants generated from incineration of the school solid wastes (SSWs) was analyzed. Components of the SSWs were identified and the SSWs were classified into combustible and non-combustible wasts. The combustible wastes consisted of papers of 56.5^ plastics of 30.2% woods of 7.1% and fibers of 6.1% based on weight of the wastes. The moisture content and the ash content of the combustible wastes were 18~20% and 11~13% respectively. The combustible wastes of the SSWs were incinerated by using a small-scale incinerator. Fly and bottom ashes and volatile organic compounds (VOCs) were collected from the incineration. Also the metal leaching experiments on the fly and bottom ashes were performed, In analysis of metals leached from the ashes the total amounts of metals leached in the acid solution (pH=3) were much greater than those in the neutral solution (pH=5.8~6.2) For the same amounts of the fly and bottom ashes the total amounts of metals leached from the fly ashes were much greater than those from the bottom ashes. The VOCs produced from incineration of the SSWs consisted of aromatics of 42.1% aliphatic alkenes of 26.3% oxidized forms of 17.3% and aliphatic alkanes of 14.3% In addition the considerable amounts of hazardous air pollutants (e.g benzene chloro-benzene and chloro-alkanes) and compounds (e. g, aliphatic alkenes) with high potential of ozone or photochemical smog formation were identified from the incineration experiment of the SSWs.

• 문화기술의 융합
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• 제5권4호
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• pp.67-77
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• 2019

화장률의 증가로 매장중심에서 화장중심의 문화로 바뀐 우리나라는 봉안을 선호하였으나 봉안시설의 사후 처리문제 등으로 화장한 유골의 새로운 처리 방법인 '자연장 제도'를 도입했다. 화장이후 봉안과 자연장 방법 이외의 산골도 요구되고 있으나 현실까지는 법제화되어 있지 않다. 본 연구는 화장한 유골을 처리하는 산골에 대한 문헌고찰을 장사등에관한 법률에서 정한 '화장한 유골을 뿌리는 시설'에 대해 현황 조사하였다. 조사 결과 화장한 유골을 뿌리는 시설은 공설화장시설 58개소 중 총 42개소가 있었는데 그중 40개소 시설의 명칭이 유택동산이었다. 수도권 공설화장시설 종사자에게 '화장한 유골을 뿌리는 시설'인 산골시설에 대해 설문조사를 실시하였다. 분석결과 95.9%가 산골시설을 알고 있다고 했으며 88.2%는 개선할 부분이 있다고 답하였다. 본 연구는 현황조사와 분석결과를 토대로 산골의 법제화와 산골시설의 다양화 및 현대화 등 개선방안을 제언하고 있다.

• Computers and Concrete
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• 제20권2호
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• pp.197-204
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• 2017

Typically, high lime fly ash (Class C) has been characterized as a fly ash, which at lower replacement levels is not as effective as the low lime (Class F) fly ash, in mitigating alkali-silica reaction (ASR) in portland cement concrete. The influence of fineness of Class C, obtained by grinding virgin fly ash into finer particles, on its pozzolanic reactivity and ASR mitigation performance was investigated in this study. In order to assess the pozzolanic reactivity of mortar mixtures containing virgin or ground fly ashes, the strength activity index (SAI) test and thermo-gravimetric analysis (TGA) were conducted on the mortar cubes and paste samples, respectively, containing virgin fly ash or two ground fly ashes. In addition, to evaluate any improvement in the ASR mitigation of ground fly ashes compared to that of the virgin fly ash, the accelerated mortar bar test (AMBT) was conducted on the mortar mixtures containing different dosages of either virgin or ground fly ashes. In all tests crushed glass aggregate was used as a highly reactive aggregate. Results from this study showed that the finest fly ash (i.e., with an average particle size of 3.1 microns) could increase the flow ability along with the pozzolanic reactivity of the mortar mixture. However, results from this study suggested that the fineness of high lime fly ash does not seem to have any significant effect on ASR mitigation.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2001년도 The 6th International Symposium of East Asian Resources Recycling Technology
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• pp.659-663
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• 2001

In Japan, the municipal solid waste, which amounts to 50 million tons, is generated every year and most of it is incinerated. The bottom and fly ashes are disposed to the registered disposal areas under the provisions of The Waste Disposal and Public Cleaning Law. Especially, as the fly ash from the municipal waste incineration (the primary fly ash) contains heavy metals (lead, zinc, etc) and dioxins, it cannot be disposed directly without decontamination, such as moiling, cementation, chelating and dissolving processes provided in the law. However, these procedures for decontamination, except melting, are not enough for dioxins. Even in case of melting, the fly ash from the process (the secondary fly ash) contains high concentration of heavy metals (e.g., Zn; 1-20%, Pb; 1-10%). For these reasons, Metal Mining Agency of Japan (MMAJ), a governmental organization, started a four-year project to develop the treatment technologies of these fly ashes in 1999. The purpose of the project is to establish the integrated technologies to recover the valuable metals from, and to decontaminate, the primary and secondary fly-ashes in the practical scale by utilizing the existing metallurgical processes and facilities, along with the energy saving and the reduction of the environmental impact.

• 대한설비공학회지:설비저널
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• 제11권4호
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• pp.19-33
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• 1982

우리나라에서 대량으로 제기되는 연탄재는 밀도가 낮으면서도 충분한 강도를 가지며 표면적을 많이 제공할 뿐만 아니라 흡착성이 있으므로 고정미생물막공법에서 매질로 사용하여 유기성 폐수를 처리하면 유기물 제거효율이 매우 높을 뿐만 아니라, 처리수의 BOD농도를 표면부하나 용적부하로 계산할 수 있으므로 처리시설의 설제가 용이한 경제적인 폐수처리공법이 될 수 있다. 그러나 연탄재 매질을 장기간 사용하면 원수내의 SS, 성장한 미생물의 탈리 등에 의하여 처리수의 수질이 악화될 수도 있으므로 종말침전지가 요구될 수도 있다.

• Asian-Australasian Journal of Animal Sciences
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• 제7권1호
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• pp.63-68
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• 1994

432 samples of raw goat milk were analyzed for sodium, calcium, potassium, chloride, and ashes content. The samples came from 16 pure breed goats, 2 to 4 years of age kept in semi-feedlots. They were basically fed soy bran, cotton bran, triturated Guandu hay and disintegrated corn with its straw and corncob (according to requirements for due preservation and production). The mean values found were: sodium, $45{\pm}10.2mg%$ (24.5-65.6 mg%); potassium, $206{\pm}44.7mg%$ (116.6-295 mg%); calcium, $111{\pm}22mg%$ (66.5-155.4 mg %); ashes, $0.82{\pm}0.06mg%$ (0.68-0.95%); chloride, $235{\pm}39mg%$ (157-313 mg%). Results were related to: a) breed, the Brown and the Saanen revealed superior values for calcium and ashes, b) climate, which in the rain season led to higher contents of sodium, potassium, and calcium when compared to the local dry season, c) time of lactation which increasingly affected the contents of calcium, sodium and ashes, and d) the time between milking, when higher concentration of chloride and ashes were mostly concentrated in the evening and calcium in the morning. These results have important implications in the handling and management of the goat herd.