• 한국재료학회지
• /
• 제32권1호
• /
• pp.23-29
• /
• 2022

Fly ash is a by-product of coal fired electrical power plants and used as a material for cement and concrete; particularly, imported fly ash is mainly applied for cement production. Main objectives of this article are to replace domestic fly ash with an imported source. To verify the possibility of domestic fly ash as a material for cement from the aspect of chemical composition and physical properties, we manufactured various kinds of cement, such as using only natural raw material, shale, and partial replacement with domestic and imported fly ash. When we used the domestic and imported fly ash, there were no specific problems in terms of clinker synthesis or cement manufacturing in relation to the natural material, shale. In conclusion, domestic fly ash has been confirmed as an alternative raw material for cement because 7 days and 28 days compressive strength values were better than those of reference cement using natural raw material, on top of the process issue.

• 한국건축시공학회지
• /
• 제14권2호
• /
• pp.187-194
• /
• 2014

With environmental regulations continuously being strengthened internationally the need to control environmental pollution and environmental load is emerging in Korea. The purpose of this study is to seek methods or using waste cementitious powder as an alternative raw material for limestone through the optimization of raw material and to quantitatively analyze the resulting reduction of $CO_2$ emission in order to contribute to solving the issue of waste, which is the biggest issue in relation to construction and global warming. The results of the study, show that waste cementitious powder can be used as an alternative raw material for limestone at OPC level, but it was also found that mixing fine aggregate cementitious powder into waste cementitious powder significantly affected the substitution rate for limestone with waste cementitious powder and the reduction of greenhouse gas. In particular, when fine aggregate cementitious powder was used at a rate of 0~20%, the substitution rate for limestone and the reduction in the rate of greenhouse gas emission was significantly reduced. It is thought that a technique to efficiently separate and discharge the fine aggregate cementitious powder mixed in waste cementitious powder needs to be developed in the future.

• 한국건설순환자원학회논문집
• /
• 제11권1호
• /
• pp.1-8
• /
• 2023

본 연구에서는 시멘트 제조 공정 CO₂ 배출을 저감하기 위해 철강 슬래그로 시멘트 원료로 사용되는 석회석 사용량을 대체할수 있는 수준을 시뮬레이션 방법을 이용하여 평가하였다. 이를 위해 석회석을 비롯한 시멘트 각 원료와 석회석 대체원료로서 고로 서냉 슬래그, 전로 슬래그, KR 슬래그의 화학성분을 바탕으로 최적 시멘트 원료 배합을 도출하는 시뮬레이션 분석을 수행하였다. 분석 결과, 슬래그 대체원료는 일정 수준의 CaO를 함유해 석회석 사용량을 일부 저감하는 비탄산염 대체원료로 사용할 수 있음을 확인하였다. 동시에 각 원료의 최대 사용 가능 수준을 도출하였는데. 특히 이들 원료를 각기 사용하는 경우보다 혼합해서 사용하면 석회석 저감 효과를 증대해 탈탄산 반응에 의한 CO₂ 배출을 저감하는데 기여할 수 있는 것으로 평가되었다.

• 한국건축시공학회:학술대회논문집
• /
• 한국건축시공학회 2015년도 추계 학술논문 발표대회
• /
• pp.3-4
• /
• 2015

Environmental load reduction and sustainable development one of the study's research into the available material is discharged, remove the coarse aggregate and fine aggregate from waste concrete and utilizing the remaining cement fine powder as an alternative raw material for limestone is the main raw material of cement developing playback cement that was the purpose. Physical over existing research and chemical quality was confirmed was evaluated for durability by promoting carbonation test, research studies on the durability evaluation insignificant. As honipyul within the aggregate differential lung fine powder increases carbonation resistance performance've found that increased sharply and, S0 showed fairly similar to the OPC. Therefore, the development within the technology research to separate fine aggregate discharge fully differential and waste fine powder is determined to be the development and use of the playback durability of the cement with the carbonation levels corresponding to the OPC if made.

• Journal of Magnetics
• /
• 제8권3호
• /
• pp.118-120
• /
• 2003

As an alternative promising way of producing high coercivity Sr-ferrite for a permanent magnet application, intensive mechanical milling process was applied to the raw materials of the Sr-ferrite with different composition. Synthesising reactivity for the Sr-ferrite of the mechanically milled raw material containing $SrCO_3$, $La_2O_3$, $Fe_2O_3$, $Co_3O_4$, and $SiO_2$ was inferior to that of the raw material containing $SrCO_3$ and $Fe_2O_3$, The Sr-ferrite prepared from mechanically milled raw materials had profoundly improved magnetic properties compared to the Sr-ferrite prepared by conventional method. Beneficial effect of the substituting ($La_2O_3$, $Co_3O_4$) and additive ($SiO_2$) oxides for improving the magnetic properties was not exploited in the Sr-ferrite prepared from the mechanically milled raw material. The Sr-ferrite powder prepared from the mechanically milled raw materials was magnetically isotropic in nature.

• 시멘트 심포지엄
• /
• 통권49호
• /
• pp.25-26
• /
• 2022

화력발전소에서 발생하는 석탄회의 경우 콘크리트용 혼합재 용도 이외 잔재물은 대부분 폐기/매립되고 있는 실정이다. 매립되고 있는 석탄회도 시멘트용 원료로 대체 사용이 가능하나, 해수접촉에 의한 염소함량 및 수분 제어가 필수적이다. 따라서 본 연구에서는 매립 석탄회의 시멘트 원료 활용을 위한 제반 공정 기술개발을 추진 중에 있다.

• 식품보건융합연구
• /
• 제8권4호
• /
• pp.11-21
• /
• 2022

Spirulina is known to be more useful abroad than in Korea because it contains more protein than Chlorella, the same microalgae. In the past, sources of animal protein were diverse, but since it takes a long time to receive protein along with environmental pollution, we thought that spirulina could attract attention as a new protein source. In this study, application cases were analyzed in foods in the fields of acorn cake, tofu, dumpling skin, fish cake, white bread, pound cake, salad dressing, and yogurt and so on. As a result of centrally analyzing antioxidant and sensory evaluation, it was confirmed that the results were effective enough to develop products in tofu, dumpling skin, fish cake, and pound cake. It is thought that development of food in other fields will be possible if an additive amount that can match the consumer's preference is found by supplementing the mixing ratio. If it is used as a main raw material for existing food rather than as a raw material for health functional food, consumer preference can increase and quality can be further improved, and it can be suggested as a good alternative for an aging society.

• 한국결정성장학회지
• /
• 제33권6호
• /
• pp.210-215
• /
• 2023

조합 원료의 소성성은 시멘트 제조 기술에서 매우 중요한 요소이며, 각 원료들의 물리적, 화학적 및 광물학적 특성에 의해 좌우된다. 본 연구에서는 국내산 석탄재와 일본산 석탄재를 시멘트 원료로 사용했을 경우, Lafarge 평가 방법과 Polysius 평가 방법을 이용하여 소성성을 비교하였다. 석탄재의 종류와 투입량에 관계없이 석탄재를 사용하였을 경우가 석탄재를 사용하지 않았을 때 보다 소성성이 향상됨을 알 수 있었다. 모든 종류의 석탄재에서 투입량이 증가할수록 소성성이 향상되었으나, 3 %까지 소성성의 향상이 뚜렷하였고 4 % 첨가 시에는 향상 폭이 상대적으로 크지 않았다. 결론적으로 시멘트의 품질이 허용하는 범위 내에서 석탄재의 투입량이 증가할수록 소성성이 향상되며, 따라서 클링커의 소성에 필요한 연료비의 절감도 기대할 수 있다.

• 한국콘크리트학회:학술대회논문집
• /
• 한국콘크리트학회 2005년도 봄학술 발표회 논문집(II)
• /
• pp.477-480
• /
• 2005

The discharge of sewage sludge is rapidly increasing in Korea. But the most common sewage sludge disposal alternative is to incinerate and to deposit it in controlled landfills. However, space limitations on existing landfill sites, and increasing environmental concerns have prompted the investigation of alternative ash disposal routes. The utilization of sewage sludge ash would contribute to the elimination of an environmental problem and to the development of new high-performance materials. The purpose of this study is to apply to Alkali Activation into solidification of sewage sludge ash. It achieves leaching test, chemical composition and compressive strength test. As a result of tests, the sewage sludge ash has sufficient potential for use of pozzolanic raw material. However, it is judge to be available to construction material if research is continuously gone.

• 한국건축시공학회지
• /
• 제14권1호
• /
• pp.54-60
• /
• 2014

The purpose of this study is to examine whether cementitious powder separated from waste concrete can be used as an alternative raw material to limestone and reduce the usage of natural resource (limestone) and $CO_2$ emission based on recycling cementitious powder from waste concrete. Experiments actually analyzed the chemical composition of cementitious powder and performed hyperthermia analysis, measurement of free CaO and XRD analysis to measure the degree of recovery of hydration in the model of cementitious powder manufactured based on chemical composition. These were performed in each cementitious powder model at different calcination temperatures such as $900^{\circ}C$, $1200^{\circ}C$, $1300^{\circ}C$, $1400^{\circ}C$ and $1450^{\circ}C$. Through the experiments, it was found that the recovery of hydration was at a level which can be used as the alternative raw material for limestone, but the replacement ratio was directly affected by the degree of mixing of fine aggregate in less than $150{\mu}m$, which cannot be separated from cementitious powder. It was shown that there was no difference in the production of compounds involved in hydration at calcination temperatures of $1200^{\circ}C$ or higher. Therefore, to pursue the replacement of limestone and reduction of greenhouse gas by recycling cementitious powder, the development of technology to efficiently separate aggregate fine powder is required.