• Proceedings of the Korea Concrete Institute Conference
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• 2002.05a
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• pp.569-574
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• 2002

Generally, the limestone powder is known to have some advantages in rheology of fresh concrete, resistance of material separation, and enhancement of strength at early ages. Recently, great attention is being paid to limestone blended cements in the manufacture of concrete, especially in the countries of Europe. The purpose of the present study is to establish the mechanical and durable properties of concrete containing slag and limestone powder. In this paper, the chloride ion penetration test, rapid carbonation test and rapid freezing-thawing test is carried out to study durability of concrete with various content of limestone powder. Futhermore, the strength of concrete is evaluated with various ages.

• Journal of Environmental Health Sciences
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• v.30 no.3
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• pp.239-244
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• 2004

The purposes of this study were to examine applicability of limestone as a conditioning agent and to determine the optimum conditions for improving dewaterability of digested sludge. The optimum conditions for temp., pH, dosage, particle size, time, and pressure was $30^{\circ}C$, 7, 45 g/l, 100 mesh, 30 min., and $2.66 {\times} 10^4 N/m^2$, respectively. On the basis of induced optimum conditions, if adding limestone in digested sludge, it estimated that its specific resistance was $1.43 {\times} 1012 m/kg$. Therefore, it seemed that we could utilize limestone as conditioning agent for improving dewaterability of digested sludge.

• Journal of the Korean Ceramic Society
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• v.43 no.9 s.292
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• pp.537-543
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• 2006

Length change, hydration heat, setting time and compressive strength of OPC were measured by adding KCl and replacing limestone powder so as to examine the influence of limestone powder on hydration of the OPC contained much chloride. In general, the chloride modified cement was high in heat of hydration, short in its setting time, low in its fluidity and low in its strength at 28 days due to the sudden hydration in its initial stage. As a result of the experiment, it has been demonstrated that heat of hydration, became low as one replaced limestone powder to the chloride modified cement, and the fluidity and shrinkage rate of mortar decreased without change in setting time; furthermore, the compressive strength at 28 days was improved.

• The Journal of Engineering Geology
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• v.11 no.2
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• pp.131-139
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• 2001

Until recently, limestone yield production is mainly depend on geological investigation and boring. In the study seismic and electrical method are applied to calculate the basic data of limestone yield production. the result of geophysical prospecting, the depth of bed rock is approximately 17m. And there is a slightly difference between the limestone layer boundary which is drawn by electrical prospecting method and that of geological investigation.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2019.11a
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• pp.178-179
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• 2019

The cement industry is a large amount of carbon dioxide emission industry, and research and development on non-cement composition is underway at the time when the absolute reduction of cement use is urgently needed. In addition, limestone fine powder is a by-product and is required to be recycled in terms of resource circulation. The compressive strength of the lime cement powder added noncement composition showed that the compressive strength increased as the limestone powder was added. It is believed that limestone fine powder played a role of stimulant such as alkali activator in non-cement composition.

• Journal of the Korean Ceramic Society
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• v.46 no.1
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• pp.47-52
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• 2009

Lime paint surpassing others in execution efficiency, anti-bacterial, anti-mold and small quantity emission of VOCs(Volatile Organic Compounds) characteristics was developed using a limestone as raw materials. The lime paint prepared by mixing slaked lime($37{\sim}40\;wt%$), PVA:EVA(9 wt%:1 wt%), talc(23 wt%), $TiO_2$(14 wt%), zeolite (3 wt%), antifoaming agent(5 wt%), wetting agent (5 wt%) was indicated over 99.8% of anti-bacterial and anti-mold characteristics. Also, the environment-friendly function of the lime paint was confirmed by detection of small amount of TVOCs($0.01\;mg/m^2h$) and formaldehyde($0.008\;mg/m^2h$). Execution efficiency, economy-and environment-friendly characteristics of this lime paint can make up for defects of established paints. And, it also presents the advantage of a limestone as high value added materials.

• Journal of environmental and Sanitary engineering
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• v.14 no.3
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• pp.99-106
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• 1999

This research was carried out to investigate chemical pretreatment using lime and limestone in treating abandoned mine drainage with anaerobic treatment. If treating lime with abandoned mine drainage, after 2day, pH was increased to 5.6, and $SO_4^{2-}$, Fe, Al, Pb and Mn were removed 5.7%, 63%, 57, 45% and 28%, respectively. It was estimated that lime dosage was 2,000mg/L for increasing to pH 7. If treating limestone with abandoned mine drainage, after 2day, pH was increased to 3.67, and $SO_4^{2-}$, Fe, Al, Pb and Mn were removed 4.7%, 26%, 22% 18% and 8%, respectively. It could be showed that limestone did slowly react with temperature increasing. If treating anaerobic limestone packing column with abandoned mine drainage, for experimental period, average pH was 4.51, and average $SO_4^{2-}$, Fe, Al, Pb and Mn were removed 4.5%, 15.3%, 20.1%, 23.7% and 5.87%, respectively. So, it would not be suitable for abandoned mine drainage. But if utilizing limestone as pretreatment process for treating abandoned mine drainage with SRB, because it did initally neutralize abandoned mine drainage, it could forward to stabilize system.

• Journal of Environmental Health Sciences
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• v.32 no.5 s.92
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• pp.469-477
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• 2006

When denitrification was connected with a single stream process by using biofilter and sulfur-limestone, it was found that such connection enabled highly efficient nitrification without special unit operation of microorganisms or injection of external carbon sources which is being shown in general biological treatment processes. It was observed that in the trickling filter bed, decomposition of organic substances and highly efficient nitrification by both the forced pressure feed trickling and the air fan were simultaneously done. In the denitrification tank where sulfur-limestone was mixed at a certain ratio, limestone was used by autotrophic microorganisms as a source of supply for alkalinity, and nitrate $NO_{3}^{-}$-N was denitrified into nitrogen gas. And in the sulfur-limestone autotrophic denitrification, $NO_{3}^{-}-N\;or\;NO_{2}^{-}-N$ was denitrified as a sulfur compound in reduction state was oxidized into a final output of $SO_{4}^{-2}$. The mean concentration of the discharge water was 8.6 mg/l for T-N and 0.8 mg/l for T-P, respectively, and their mean treatment efficiency was 79.2% and 80.8%, respectively. Implementing highly efficient denitrification without injection of an external organic carbon source or internal return, it is concluded that the proposed process is suitable for a sewerage in a small village with the merits of low power consumption and easy maintenance.

• Resources Recycling
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• v.24 no.6
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• pp.17-23
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• 2015

Flue gas desulfurization(FGD) is the technique to remove $SO_2$ gas from stack gases of coal-fired plants. Many researcher have studied to replace the desulfurizing agent because FGD systems use a lot of limestone and energy. In this study, we use the limestone sludge which is a by-product of steel industry in order to replace desulfurizing agent of FGD system by control the particle size of limestone sludge. And desulfurization performance test is implemented by investigating $SO_2$ gas removal properties upon the characteristic of the limestone sludge with various particle size.

• Journal of the Korea institute for structural maintenance and inspection
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• v.15 no.1
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• pp.129-137
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• 2011

This study aims to evaluate the resistance to seawater attack of mortars and concretes incorporating limestone powder (0, 10, 20 and 30% of cement by mass). In order to achieve this goal, both chemical resistance by seawater and chloride ions penetration resistance of mortars or concretes were regularly monitored. From the test results, it was observed that the durability of cement matrix was greatly dependent on the replacement ratios of limestone powder. In other words, performance of cement matrix with 10% limestone powder was similar to that of OPC matrix. However, it was found that a high replacement ratio of limestone powder was ineffective to resist seawater attack.