• Korean Journal of Materials Research
• /
• v.32 no.1
• /
• 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.

• Journal of the Korean Recycled Construction Resources Institute
• /
• v.11 no.1
• /
• pp.1-8
• /
• 2023

In this study, to reduce CO₂ emission in the cement manufacturing process, we evaluated the limestone that is used as a raw material for cement, substituted with steel slag by the various substituted levels. Based on the chemical composition of each raw materials including limestone, and blast furnace slow cooling slag, converter slag, and KR slag as an alternative raw material, we simulated the optimal cement raw mixture by the substitution levels of limestone. Test results indicated that the steel slags contain a certain level of CaO that can be used as alternative decarbonated raw materials, and it has enough to partially reduce the amount of limestonem. And we estimated the maximum usable levels of each raw material. In particular, it was confirmed that by using a mixture of these raw materials rather than using them one by one, the effect of reducing limestone was increased and CO₂ emission from the cement manufacturing process could be reduced.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2015.11a
• /
• 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.

• Cement Symposium
• /
• s.49
• /
• pp.25-26
• /
• 2022

Coal ash generated from thermal power plants has been used as alternative raw material for cement production. But when using buried coal ash, careful attention is needed because it contains some amount of moisture and chlorides which can cause problems in production process. In this project, cement production process and quality control technology for using buried coal ash as cement raw material has been being developed.

• Computers and Concrete
• /
• v.10 no.5
• /
• pp.457-467
• /
• 2012

Using appropriate raw materials for cement is crucial for providing the required products. Monitoring relationships and analyzing distributions in a cement material quarry are important stages in the process. CaO, one of the substantial chemical components, is included in some raw materials such as limestone and marl; furthermore, appraising spatial assessment of this chemical component is also very critical. In this study, spatial evaluation and monitoring of CaO concentrations in a cement site are considered. For this purpose, two effective regression-based models were applied to a cement quarry located in Turkey. For the assessment, some spatial models were developed and performance comparisons were carried out. The results show that the regression-based spatial modelling is an efficient methodology and it can be employed to evaluate spatially varying relationships in a cement quarry.

• Journal of the Korean Recycled Construction Resources Institute
• /
• v.9 no.1
• /
• pp.20-25
• /
• 2021

The cement clinker, the main raw material of cement, is manufactured using limestone as the main material. Depending on the quality of limestone, the use of subsidiary materials changes, and has a great influence on the production of cement clinkers. In this study, the effect of CaO content of limestone, a cement clinker material, on Raw Mill grinding and sintering of cement clinker was investigated. The grinding time of the union materials changed in the content of limestone CaO was measured to identify the grinding properties. The raw material combination was cleaned within a range of 1,350-1,500℃. The sintering performance of cement clinker by Burnability index calculation was identified. The lower the grade of limestone, the lower the grinding quality of the raw material combination. The lower the CaO content of limestone, the greater the variation in F-CaO for sintering temperature. The lower the class of limestone, the higher B. I. value was calculated, indicating the lower cement clinker sintering. In addition, the mineral analysis results of cement clinker showed that if the F-CaO value was low due to the increase in sintering temperature, the Belite content decreased and the Alite content increased. In the case of Alite, the ratio of R-type decreased and that of M-type increased as the content of limestone CaO increased.

• Journal of the Korean Crystal Growth and Crystal Technology
• /
• v.33 no.6
• /
• pp.210-215
• /
• 2023

Raw mix burnability is an especially crucial factor in cement manufacturing technology, and it depends on the physical, chemical and mineralogical properties of each raw material. In this article, we compared the difference of burnability between the domestic and Japanese fly ash as cement raw materials by using Lafarge and Polysius evaluation method. Regardless of the type or amount of fly ash used, it was found to be more combustible when using fly ash. In both case, burnability improves as the amount of fly ash increases, especially the improvement in bunarbility is remarkable up to 3%. In conclusion, as the amount of fly ash increases within the range allowed by cement quality, burnability of raw materials improves, and thus the fuel cost required for the firing of clinker can also be expected to be reduced.

• Proceedings of the Korea Concrete Institute Conference
• /
• 2006.11a
• /
• pp.729-732
• /
• 2006

Portland cement is presently the most widely used construction material. The process of manufacture of cement consists essentially of grinding the raw materials, mixing them intimately proportions and burning in a rotary kiln at a temperature of up to about $1450^{\circ}C$. Raw materials have used limestone, clay, silica, and iron oxide and fuel have used bituminous coal. Recently, A standpoint of the recycling of material resources, the production of cement use of industrial waste and residual products. Therefore, the final product of cement were included heavy metals such as $Cr^{+6}$ and Pb. The purpose of this study is standardization for $Cr^{+6}$ analysis in cement and concrete. From the comparative study of the examination method of $Cr^{+6}$ analysis, Japan cement association standard of $Cr^{+6}$ analysis is most suitable for the real state of affairs in korea.

• Journal of the Korean Ceramic Society
• /
• v.41 no.4
• /
• pp.323-327
• /
• 2004

This study has been carried out to use the municipal solid waste sewage sludge ash generated at sewage disposal field as the raw materials of Ordinary Portland Cement (OPC). Limestone, shale, converter slag, and fly ash were used as the main raw materials. After the raw materials were mixed, these were fired at 1,300, 1,350, 1,400, 1,450, and 1,500$^{\circ}C$ for 1 h and cooled rapidly in air. The properties of clinker synthesized were examined with XRD, SEM, and burnability index by polysius method.

• Journal of the Korean Recycled Construction Resources Institute
• /
• v.7 no.1
• /
• pp.22-28
• /
• 2019

Cement is a basic material for the construction industry and it requires high temperature sintering when manufacturing cement. $CO_2$ emissions from raw materials and fuels are recognized as new environmental problems and efforts are underway to reduce them. Techniques for reducing $CO_2$ in concrete are also recommended to use blended cement such as blast furnace slag or fly ash. In addition, the construction waste generated in the dismantling of concrete structures is recognized as another environmental problem. Thus, various methods are being implemented to increase the recycling rate. The purpose of this study is to utilize the inorganic raw materials generated during the dismantling of the structure as a raw material for the low carbon type cement binder. Such as, waste concrete powder, waste cement block, waste clay brick and waste textile as raw materials for low carbon type cement binder. From the research results, low carbon type cement binder was manufactured from the raw material composition of waste concrete powder, waste cement block, waste clay brick and waste textile.