• 에너지공학
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• 제23권2호
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• pp.42-48
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• 2014

미분탄의 연소 또는 열분해 과정으로부터 발생하는 tar-soot는 복사 열전달 및 질소산화물의 추가적인 발생 원인이라는 관점에서 의미 있게 다루어지고 있다. 최근 저열량탄이 증가함에 따라 시멘트의 원료로 재활용되던 석탄회에서 다량의 미연분과 tar-soot가 포함되어 오히려 다시 반입되는 사례가 빈번해지고 있다. 따라서 본 연구에서는 저열량탄 사용 확대에 따른 혼탄연소 조건에서 tar-soot의 배출특성을 살펴보기 위해 반응기로써 LFR(Laminar Flow Reactor)을 적용하였으며, 연료로는 현재 국내발전소에서 사용 중인 역청탄 2종(MOUNTAIN, MACARHTUR)과 아역청탄(KPU)을 이용하여 단탄별 tar-soot 배출특성과 혼소비에 따른 배출특성을 화염의 구조 변화와 함께 측정하였다. 휘발분이 많은 아역청탄의 soot cloud 길이는 역청탄에 비해 길었지만 전체적인 화염 길이는 짧아졌다. 단탄별 실험결과에서는 역청탄의 tar-soot 발생량이 아역청탄의 발생률보다 높았으며 역청탄 중 휘발분 함량이 많은 MOUNTAIN탄이 상대적으로 휘발분 함량이 적은 MACARHTUR탄의 tar-soot 발생률보다 높았다. 혼소시에는 단탄의 연소특성과는 다른 새로운 특성을 나타내었으며 저열량탄과 혼소되는 역 청탄의 종에 따라 tar-soot 발생량이 지배되는 것을 확인하였으나 혼소비에 따른 평균적 특성이 아닌 완전히 차별되는 배출특성을 나타냄에 따라 석탄의 등급에 따라 최적의 혼소비를 찾아서 연소시키는 것이 tar-soot 발생량을 줄일 수 있는 방법임을 의미한다.

• 한국건축시공학회지
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• 제1권2호
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• pp.179-184
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• 2001

The most recent building trend is going large, high rise, high strength as overlarge project is developing in domestic construction business. Belite cement has properties like low heat, excellent long term strength, and durability without admixture(fly ash, silica fume). so, Beilte cement is suitable for mass structure which is needed high strength, high fluidity and low heat property. This study is to examine the possibility if site adoption microwave-use early strength estimation method. Based on the existed study related the portland cement, the interrelation between Belite cement and microwave-use early strength estimation method is required. In this study, interrelation between mortar and Evaluating strength estimation method is investigated before the concrete experiment.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1998년도 가을 학술발표회 논문집(I)
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• pp.66-71
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• 1998

Recently, it has been increased to construct massive concrete structures, like under-ground structure, offshore structure etc., ie. concrete construction have become larger and higher and are demanding lower heat concrete to prevent thermal cracking. It has been progressed to replace cements with fly-ash and slag to lower heat of hydration, but it is hard to control quality of the mineral admixtures in stage of adjusting of real construction. Application of low heat portland(Belite Rich) cement for the mass concrete is the best solution to satisfied those requirements. Here are explained the basic properties of fresh concrete as well as hardened concrete of using low heat portland cement(LHPC). Also, we compare the results of adiabatic temperature rise test using LHPC and OPC.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2001년도 가을 학술발표회 논문집
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• pp.1077-1082
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• 2001

The most recent building trend is going large, high rise, high strength as overlarge project is developing in domestic construction business. Belite cement has properties like low heat, excellent long term strength, and durability without admixture(fly ash, silica fume). so, Belite cement is suitable for mass structure which is needed high strength, high fluidity and low heat property. This study is to examine the possibility of site adoption microwave-use early strength estimation method. Based on the existed study related the portland cement, the interrelation between Belite cement and microwave-use early strength estimation method is required. In this study, interrelation between mortar and Evaluating strength estimation method is investigated before the concrete experiment.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2001년도 가을 학술발표회 논문집
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• pp.297-302
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• 2001

SRC pier at KTE 6-1 construction area is a very important structure. Precise control of quality is needed. This pier has 3.50m$\times$3.73m section and 38.20m length. So this structure must be treated as mass concrete and thermal crack caused by hydration heat should be controled. In this project belite cement concrete is used to control the thermal crack. As a result of adapting belite cement concrete perfect control is achieved. Finally, hydration heat FEM analysis of horizontal element is executed for Ordinary Portland Cement concrete and belite cement concrete. In comparison of two results, it is confirmed that using low heat portland cement concrete is necessary.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2001년도 가을 학술발표회 논문집
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• pp.303-308
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• 2001

Recently, concrete structures have become larger and higher and are demanding high performance concrete with lower heat to prevent thermal cracking, far greater workability, high strength and durability, Application of low heat portland(Type IV) cement for the high performance concrete is the best solution to satisfied those requirements. Here are explained the effect on the properties of high flowing concrete using low heat portland cement by material and mixing variations. Variables for sensitivity test were selected items like finess modulus of aggregates, particle size of limestone powder, unit water, superplasticizer, viscosity agent and concrete temperature. The results of this study were be applied to slurry wall of #215 and #216 of underground LNG tank in Inchon.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2005년도 추계 학술발표회 제17권2호
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• pp.603-606
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• 2005

Strength development of low heat portland cement(Type IV) concrete according of addition of fly-ash in high strength range is tested. In this study strength development according to water-binder ratio, strength development according to age, effect of fly ash are tested. This study tests effect of low heat portland cement in high strength range concrete and provide guide line concrete mix design for later study and construction.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2006년도 춘계 학술발표회 논문집(II)
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• pp.445-448
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• 2006

In order to control the temperature crack of massive dam concrete, the selection of appropriate materials like binder, aggregates etc., is essential. To select the optimal mix proportion, ordinary portland cement(Type I) plus 25% of fly ash and low heat portland cement(Type IV) are used as binder, and 80mm of coarse aggregates are used to reduce the amount of binder and compare the compressive strength, hydration temperature and crack index. The results of this study are as following. 1. The strength of Type IV cement is advantageous on the long-term age. 2. According to the temperature measured on mock-up$(1.5m{\times}1.5m{\times}1.5m)$, and realized the thermal analysis, the Type IV cement carried out advantageous to control the thermal crack.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2003년도 봄 학술발표회 논문집
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• pp.1041-1046
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• 2003

The most recent building trend is going large, high rise, high strength as overlarge project is developing in domestic construction business. Belite cement has properties like low heat, excellent long term strength, and durability without admixture (fly ash, silica fume). So, Belite cement is suitable for mass structure which is needed high strength, high fluidity and low heat property. This study is to examine the possibility of site adoption microwave-use early strength estimation method. Based on the existed study related the portland cement, the interrelation between Belite cement and microwave-use early strength estimation method is required.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2005년도 봄학술 발표회 논문집(II)
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• pp.17-20
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• 2005

In this study, the properties of autogenous shrinkage stress and dry shrinkage stress for high strength concrete using Type I and Type IV cement were discussed. According to experimental results, autogenous shrinkage stress of SN30(the high strength concrete using type I cement) shows values higher than SL30(the high strength concrete using type IVcement). It is observed that the total shrinkage stress of SN30 is higher than that of SL30, because the ratio of autogenous shrinkage stress of the total shrinkage stress is relatively large. Therefore, SL30 is more effective to control or minimize the cracking of the high strength concrete, compared with SN30.