• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2017년도 추계 학술논문 발표대회
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• pp.225-226
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• 2017

Recently, there has been a growing interest in the development of non-sintered binder to reduce CO2 emissions from the cement clinker manufacturing process and a number of studies have been conducted on fly ashes as an industrial by-product. However, in order to utilize fly ashes as a non-sintered binder, it is necessary to solve problems such as safety issues and economical efficiency due to use of an alkali activator. This study evaluates the material properties and compressive strength characteristics of three types of circulating fluidized bed boiler ashes. As a result, it was confirmed that the characteristics of each binder vary depending on the location of the power plant and the types of raw materials. In addition, it has been confirmed that the fluidized bed boiler ash shows a high compressive strength and can be used sufficiently as an non-sintered binder.

• 한국구조물진단유지관리공학회 논문집
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• 제22권5호
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• pp.119-126
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• 2018

최근 화력발전소에서는 순환유동층 연소방식의 발전소가 증가하는 추세이다. 순환유동층 보일러애시는 탈황 효과를 위해 석회석을 첨가함에 따라 애시 중에 포함되는 CaO, $SO_3$성분이 증가하여 일반적인 플라이애시 보다 free-CaO 함량이 높다. 또한 순환유동층 보일러애시는 기존의 플라이애시와 다르게 자기수경성 특성과, 높은 free-CaO함량에 의해 물과 만나면 높은 반응성을 갖는다. 본 연구는 순환유동층 보일러애시의 자기수경성 특성을 이용하여, 시멘트를 대체할 수 있는 비소성 결합재로써 활용 가능성에 대해 분석하였다. 순환유동층 보일러 애시의 함량에 따른 역학적 및 수화특성에 대해 검토하였다. 또한 석고의 종류 및 함유량에 따른 순환유동층 보일러애시 활용 비소성 결합재에 대한 압축강도 및 미세구조에 미치는 영향을 분석하였다.

• 한국건축시공학회지
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• 제18권3호
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• pp.305-312
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• 2018

This study is about the development of a non-sintered binder (NSB) which does not require a sintering process by using the industrial by-products Phosphogypsum (PG), Waste Lime (WL) and Granulated Blast Furnace Slag (GBFS). In this report, through SEM analysis of the NSB paste hardening body, micropore analysis of paste using the mercury press-in method and microstructure observation were executed to consider the influence of the formation of the pore structure and the distribution of pore volume on strength, and the following conclusions were reached. 1) Pore structure of NSB paste of early age is influenced by hydrate generation amount by GBFS and activator. 2) Through observing the internal microstructure of NSB binder paste, it was found that the strength expression at early age due to hydration reaction was achieved with a large amount of ettringite serving as the frame with C-S-H gel generated at the same time. It was confirmed that C-S-H gel wrapped around ettringite, and as time passed, the amount generated continually increased, and C-S-H gel tightly filled the pores of hardened paste, forming a dense network-type web structure. 3) For NSB-type cement, the degree of formation of gel pores below $10{\mu}m$ had a greater influence on strength improvement than simple pore reduction by charging capillary pores, and the pore size that had the greatest effect on strength was micropores with diameter below $10{\mu}m$.

• 한국건축시공학회지
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• 제18권2호
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• pp.185-193
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• 2018

In this study, using Granulated Blast Furnace Slag (GBFS), an industrial byproduct, and Phosphogypsum (PG), and Waste Lime (WL) as activator, non-sintering binder (NSB) which does not require a sintering process was produced, and the chemical penetration resistance was evaluated through a seawater resistance experiment. The result of the experiment showed that the inside of NSB mortar saw almost no influence from the ions in seawater due to its dense structure. Also, as it appears that only the surface reacts with ions in seawater while spreading inward is suppressed, the high seawater resistance of NSB could be confirmed.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2023년도 봄 학술논문 발표대회
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• pp.309-310
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• 2023

Slag and ash generally have a higher powder degree than portland cement, so workability may deteriorate under the same unit quantity condition, and strength and durability decrease when the unit quantity is increased. At this time, if an aggregate having a low water absorption and an appropriate particle size is used to recover the loss of strength, it can contribute to reducing the unit quantity of the binder. Therefore, for the purpose of improving the workability and strength of non-sintered cement mortar using slag and ash, ferro nikel slag whose particle size was adjusted was used as an aggregate and its applicability was identified. In this experimental condition, it was confirmed that non-sintered cement mortar tends to improve workability and secure strength when ferro nikel slag having various particle size distributions is used as an aggregate. This can be analyzed as the effect of ferro nikel slag material properties including glassy properties and mixing conditions with a wide particle size distribution.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2022년도 봄 학술논문 발표대회
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• pp.186-187
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• 2022

The purpose of this study was to give fluidizing properties to non-sirtered cement made using by-products that can replace Portland cement by using a fluidizing agent. Blast furnace slag, C-type fly ash, and F-type fly ash were used for non-sirtered cement, and sand was used for aggregate. The amount of fluidizing agent used was fixed at 1%, and the water-cement ratio (W/C) was different by setting the binder blending ratio of the non-sintered cement differently, and the fluidity test and flow were compared. As a result of the experiment, when the flow standard was 170mm when the fluidizing agent was used, the fluidizing properties were shown at an average water-cement ratio (W/C) of 36%. Through this study, it was confirmed that the fluidizing properties appeared when the fluidizing agent was used in non-sintered cement.

• 한국건설순환자원학회지
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• 제6권1호
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• pp.30-33
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• 2011

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2023년도 봄 학술논문 발표대회
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• pp.297-298
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• 2023

In the concrete industry, efforts are being made to reduce CO₂ emissions, and technologies that collect, store, and utilize CO₂ have recently been studied. This study analyzed the change in compressive strength after the accelerated carbonation test of Non-Sintered Cement(NSC) mortar. Type C Fly Ash and Type F Fly Ash were mixed in a 1:1 ratio and then mixed with Blast Furnace Slag fine powder to produce NSC. The mortar produced was cured underwater until the target age. In addition, an accelerated carbonation test was conducted under the condition of a concentration of 5 (±1.0%) of CO₂ gas for 14 days. The mortar compressive strength was measured before and after 14 days of accelerated carbonation test based on the 7th and 28th days of age. As a result of the experiment, the compressive strength was improved in all binder. In general, the compressive strength of NSC mortar subjected to the accelerated carbonation test was similar to that of Ordinary Portland Cement(OPC) mortar not subjected to the accelerated carbonation test.

• 콘크리트학회논문집
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• 제27권3호
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• pp.245-252
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• 2015

최근 친환경 구조물의 관심 증가와 함께 비소성 시멘트는 국내외적으로 활발히 연구되고 있다. 비소성 시멘트의 경우 알카리 자극제의 종류에 따라 반응생성물 및 경화체의 특성이 다양하게 나타난다. 본 연구에서는 산업 부산물인 순환유동층 보일러 애시를 자극제로 사용하여 고로슬래그 미분말 기반 비소성 시멘트를 제조하여, 순환유동층 보일러 애시의 함량에 따른 경화 특성 및 수화물을 검토하였다. 또한 비소성 시멘트 경량화에 따른 단열특성을 고찰하였다. 그 결과 수화물인 C-S-H와 ettringite가 주로 형성되었으며, 50 MPa 이상의 비소성 시멘트 경화체의 제조가 가능하였다. 또한 경량화 시 압축강도는 10 MPa로, 이때에 열전도율은 $0.127W/m{\cdot}K$ 수준이었다.

• 한국수소및신에너지학회논문집
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• 제7권2호
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• pp.157-164
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• 1996

The AB5-type metal hydride electrodes using $(LM)Ni_{4.49}Co_{0.1}Mn_{0.205}Al_{0.205}$(LM : Lanthaniumrich Mischmetal) alloy powders(${\leq}200$mesh) which were coated with 25wt% copper in an acidic bath were prepared with or without addition of 10wt% PTFE as a binder. Prior to electrochemical measurements, the electrodes were sintered at $40^{\circ}C$ for 1 and 2hrs in vacuum with Mm(mischmetal) and sponge type Ti getters. The properties such as maximum capacity, cycle life and mechanical strength of the negative electrode have been investigated. The surface analysis of the electrode was also obtained before and after charge-discharge cycling using scanning electron microscope(SEM). From the observations of electrochemical behavior, it was found that the sintered electrode shows a lower maximum discharge capacity compared with non-sintered electrode but it shows a better cycle life. For the both electrodes with or without addition of PTFE binder, the values of mechanical strength were obtained, and their values increased with increasing sintering time. However, there is little difference of discharge capacity for both electrodes.