• 한국건설순환자원학회논문집
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• 제8권3호
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• pp.333-348
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• 2020

본 총설에서는 석탄 바텀애시의 콘크리트 활용에 대한 최신의 전반적 내용을 다룬다. 최근 사용되는 두 종류의 화력발전시스템, 즉 미분탄연소와 순환유동층연소 보일러 각각으로부터 배출되는 바텀애시의 생산 과정과 물리적, 화학적 특성에 대해 분석하고, 활용 방법 및 활용을 위한 전처리 혹은 활용 대상 콘크리트의 종류에 대해 정리 하였다. 또한 바텀애시가 콘크리트의 여러 특성, 즉 유동성, 강도, 내구성에 미치는 영향에 대해 알아보았다. 그리고 바텀애시를 혼입한 콘크리트의 환경성 및 경제성에 대해 분석하였으며, 이를 통해 바텀애시의 콘크리트 내 활용의 미래를 고찰해 보았다. 바텀애시가 콘크리트 및 모르타르의 성능에 미치는 영향은 그 자체의 성능 외에도 전처리 및 가공 여부에 의해 크게 영향을 받는다. 따라서, 이 분야의 활용을 늘리기 위해서는 기술적 측면에서 분쇄 등의 약간의 물리적 가공이 필요하며, 이와 관련된 시방 및 기준의 정비가 요구된다는 것을 확인하였다. 특히 정책적 측면에서의 경제적 지원이 가능하다면 바텀애시 활용을 크게 확대할 수 있을 것으로 예상된다.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2001년도 가을 학술발표회 논문집
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• pp.29-62
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• 2001

Based on the results from investigation of behaviour of pulverized fly ashes (PFA) at laboratory and field, the way how to reduce the environmental impacts to geotechnical practices Is considered and described. In order to reduce discharged industrial by-products, it should primarily be emphasized that an effort are made as much as possible not to put into homing. Secondarily, an effort must be made to increase amount of utilization to geotechnical engineering practices. In addition, from an environmental point of view, we should challenge to create innovative materials which are eligible for controlling other wastes and remedying contamination m soils by using industrial byproducts which belong to wastes This Is a new concept in which the polluting materials can be eliminated by making use of wastes. Based on the above-stated concept, the previous and possible utilization of PFA is classified into: (1 ) reclamation, embankment or backfill material, (2) light weight geo-material, (8) soil stabilization/improvement, and (4) environmental material. The reason why PFA, in particular, slurry PFA has been used and will possibly be used more widely is due to the fact that PFA has the advantages : (i) low specific gravity leading to a light weight geomaterial, (ii) high pozzolanic activity enhancing strength, especially due to cement addition, and (iii) spherical shape of particles producing isotropy and then pumpability. As well as the concept of reducing geo-environmental impacts, the present text mainly describes the successful results at laboratory and field which have been obtained by the authors. The most important issue hi application of byproducts including PFA for geotechnical practices is to prevent leakage of polluted substances from sedimentary deposits, ground and earth structures. As one of possible techniques far achieving this purpose, a method of washing off the polluted substances by hot water is described.

• 자원리싸이클링
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• 제14권2호
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• pp.56-61
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• 2005

국내 기존의 석탄화력발전기에서 운영 중인 충수중력식 바닥재 처리시스템을 바닥재의 재활용이 가능한 건식처리시스템으로 교체하는 개선사업에 대하여 500MW${\times}$2기 발전설비를 대상으로 경제성을 분석하였다. 건식처리시스템으로의 개선 시 초기투자비는 13,415,127천원이 소요되며, 시설운영비는 연간 935,345천원이 절감될 것으로 예측되었다. 이를 기초로 경제성 평가를 수행한 결과, 개선사업 시 소요되는 초기투자비는 자본 이익률 10%에서 시설사용연한 내에 회수가 불가능하였으며, 투자이익률은 5.6%로 산정되어, 현재 국내 조건에서 개선사업은 경제성을 확보하지 못하는 것으로 평가되었다. 이는 신규발전설비에 건식처리시스템의 도입이 경제성을 확보하는 것과 유럽에서 개선사업이 경제성을 확보하는 것과 다른 결과를 보이고 있는데, 이는 회매립비 차이에 기인하는 것으로 검토되었다. 향후 국내 시장 여건의 변화에 따라 회매립비와 회판매가가 변동할 경우의 경제성 분석결과, 개선사업은 회판매가가 17,000원/톤 이상으로 상승하거나 회매립비가 15,000원/톤 이상으로 상승할 경우, 경제성을 확보할 수 있는 것으로 평가되었다.

• 한국식품영양학회지
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• 제34권5호
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• pp.526-536
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• 2021

This study was conducted to investigate the anti-obesity effect of Discorea Japonica Thunb. fermented with Monascus After inducing obesity by feeding hight fat diet (diet induced obesity model: DIO) for four weeks, each 8 rats were assigned to normal (Nor), high fat diet (HF), high fat diet containing orlistat (PC), high fat diet containing different concentration of Discorea Japonica Thunb. fermented with Monascus (UPDM_L, UPDM_H) and Discorea Japonica Thunb. (UPD) extract. Although the UPD, UPDM_L (ultrafine pulverized Discorea Japonica Thunb. fermented with Monascus: 400 mg/kg) and UPDM_H (DIO oral administration ultrafine pulverized Discorea Japonica Thunb. fermented with Monascus: 800 mg/kg) showed weight gain inhibition effects, the results of poor obesity inhibition rather than PC were confirmed. However, it showed a more effective weight loss effect in UPDM_H than UPD, and significantly reduced the weight of epididymal fat and subcutaneous fat. Furthermore, the possibility of anti-obesity effects of Discorea Japonica Thunb. fermented with Monascus can be confirmed by observing the effects of reducing serum total cholesterol, triglyceride and LDL concentrations, reducing ALT and AST levels, and inhibiting fat build-up in liver tissue. It is believed that Discorea Japonica Thunb. fermented with Monascus can be expected to utilize as a functional material that is important to improve anti-obesity and metabolic syndrome.

• International Journal of Industrial Entomology and Biomaterials
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• 제37권2호
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• pp.105-108
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• 2018

Recently matured silkworm powder was developed by RDA. In this study, the effect of pulverizing method on the particle size of matured silkworm powder was examined. FESEM was performed to observe the morphology and to measure the particle size of silkworm powder. Particle morphology of air-jet mill pulverized powder was round and smooth, however, those of roller-mill and hammer-mill pulverized mature silkworm was more harsh and square. Particle size was varied with pulverizing technique as follows; $1.1{\mu}m$ (air-jet mill), $10{\mu}m$ (roller mill), and $120{\mu}m$ (hammer mill), respectively. A proximate analysis results of air-jet mill powder showed that crude protein, crude lipid, crude fiber, and ash was 73%, 12%, 1.95%, and 3.4%, respectively. According to our results, air-jet mell technique might be used to make a tiny matured silkworm powder.

• Journal of Electrochemical Science and Technology
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• 제12권1호
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• pp.126-136
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• 2021

The electrochemical performance of all-solid-state cells (ASSCs) based on sulfide electrolytes is critically affected by the undesirable interfacial reactions between oxide cathodes and sulfide electrolytes because of the high reactivity of sulfide electrolytes. Based on the concept that the interfacial reactions are highly dependent on the type of sulfide electrolyte, the electrochemical properties of the ASSCs prepared using three types of sulfide electrolytes were observed and compared. The Li2MoO4-LiI coating layer was also introduced to suppress the interfacial reactions. The cells using argyrodite electrolyte exhibited a higher capacity and Coulombic efficiency than the cells using 75Li2S-22P2S5-3Li2SO4 and Li7P3S11 electrolytes, indicating that the argyrodite electrolyte is less reactive with cathodes than other electrolytes. Moreover, the introduction of Li2MoO4-LiI coating on the cathode surface significantly enhanced the electrochemical performance of ASSCs because of the protection of coating layer. Pulverization of argyrodite electrolyte is also effective in increasing the capacity of cells because the smaller size of electrolyte particles improved the contact stability between the cathode and the sulfide electrolyte. The cyclic performance of cells was also enhanced by pulverized electrolyte, which is also associated with improved contact stability at the cathode/electrolyte. These results show that the introduction of Li2MoO4-LiI coating and the use of pulverized sulfide electrolyte can exhibit a synergic effect of suppressed interfacial reaction by the coating layer and improved contact stability owing to the small particle size of electrolyte.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2006년도 제33회 KOSCO SYMPOSIUM 논문집
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• pp.293-298
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• 2006

There are many researches in progress on co-firing of coal and biomass to reduce carbon dioxide produced from the coal consumption. This study carried out 200 Kg/h combustion test furnace by mixing coal with timber. Coal was mixed with domestic and imported-wood around 10% to 20% based on input energy. For the mixed fuel, combustion temperature, unburned carbon and the composition of flue gas were analyzed. In addition, the tendency of slagging and fouling was examined using a probe. According to the result of the experiment, combustion temperature was depended on the kind of wood and mixing ratio. The unburned carbon loss was higher with increase of wood biomass mixing ratio, as a result, the total heat loss of furnace was slightly increased. The emission of NOx and SOx were decreased by $3{\sim}20%$ and $21{\sim}60%$ respectively. There are no difference of slagging and fouling tendency between biomass co-firing and coal burning only.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2010년도 춘계학술대회 초록집
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• pp.205.2-205.2
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• 2010

Optimum operation conditions of low-NOx MILD combustion for gaseous and solid fuels have been investigated by experimental and computer simulation. Loop reactor type MILD combustor without air pre-heater has been used in the present work. The results show that the balance of injection velocities of fuel and surrounding air is major factor for maintaining MILD combustion mode. Temperature difference between lower and upper part can be reduced less than 20 degree of Celsius. It was found that NOx emission in MILD combustion also can be remarkably reduced to more than 85% in comparison with conventional premixed combustion, and reduced to more than 50% in case of nitrogen and carbon dioxide carrying dried waste water sludge and pulverized coal in comparison with the same of air carrying. It was also found that carbon monoxide emission increase was not appeared at the time of changeover to MILD combustion mode from premixed or air carrying combustion at optimum operation condition.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2010년도 추계학술대회 초록집
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• pp.198.2-198.2
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• 2010

Three dimensional numerical analysis of the oxygen and air were performed to investigate the combustion characteristics in a Corner-type pulverized coal boiler. With the actual operation data of the power plant, the distribution of velocity, gas temperature, $O^2$, $CO_2$, $H_2O$, $N_2$ as well as the particle tracking in the boiler were investigated. The predicted values at the outlet of furnace for the gas temperature and major species concentrations gave a good agreement with the designed values. The present analysis on combustion characteristics in a boiler would provide the useful information for the stable boiler operation and in trouble shooting boiler problem.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2015년도 추계 학술논문 발표대회
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• pp.160-161
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• 2015

This research reviewed the characteristics of waste concrete sludge occurred from recycled aggregate producing process and the physical and mechanical properties of the mortar incorporated the pulverized the waste concrete sludge. From the results of the experiment, as the replacement ratio of waste concrete sludge powder was increased, the dosage of superplasticizer to satisfy the target flow of 200 ± 10 was increased, and the compressive and flexural strengths were decreased. On the other hand, when the sludge powder replacement ratio was 25 %, outstanding performance of general characteristics of mortar was obtained while it was lower than Plain mixture, thus, further detail study on various replacement ratios of waste concrete sludge powder is needed.