광학현미경을 이용한 소성 조건별 시멘트 클링커 광물의 특성 변화

추용식,김인섭,이종규,Chu, Yong-Sik,Kim, In-Seob,Lee, Jong-Kyu 한국세라믹학회 2004 한국세라믹학회지 Vol.41 No.11

광학 현미경을 사용한 시멘트 클링커의 특성 분석은 시멘트의 품질뿐만 아니라 제조공정도 예측 평가할 수 있다. 그러므로 본 연구에서는 광학 현미경(반사)으로 소성 조건을 달리한 클링커의 특성을 분석하였다. 승온 및 냉각 속도가 느려짐에 따라 alite와 belite는 성장하였으며, 특히 냉각 속도는 belite의 성장에 큰 영향을 주었다. 또한 최대 소성 온도에서의 유지 시간이 20분 증가함에 따라 alite와 belite가 약 5fm정도 성장하는 것을 확인하였으며, 최대 소성 온도가 140$0^{\circ}C$인 경우, belite의 크기는 양호하나 alite는 제대로 성장하지 않은 10~15$\mu\textrm{m}$수준이었다. The characteristic analysis of cement clinker using light microscope can evaluate not only the quality of cement but also making process. Thus this study analyzed clinkers having different burning conditions by reflective light microscope. As heating and cooling rates is decreased, alite and belite minerals grew and especially cooling rate had an effect on the growth of belite. Futhermore as the retention time in max. temperature got longer by twenty minutes, alite and belite minerals grew more about 5 $\mu\textrm{m}$. In the case of temperature 1400$^{\circ}C$ in max, the size of belite was suitable but alite was not suitable with the size of 10~15 $\mu\textrm{m}$.

고로 슬래그를 사용한 용융클링커의 광물학적 특성

추용식,서성관,임두혁,송훈,이종규,이승호,Chu, Yong-Sik,Seo, Sung-Kwan,Im, Du-Hyuk,Song, Hun,Lee, Jong-Kyu,Lee, Seung-Ho 한국세라믹학회 2011 한국세라믹학회지 Vol.48 No.6

Raw mix of molten clinker was fabricated using blast furnace slag as starting material. Raw mix was melted at 1620$^{\circ}C$ for molten clinker fabrication. It was found that molten clinker contained alite and belite equivalent to OPC clinker mineral by optical microscope and SEM. The size of alite was 10~50 ${\mu}m$ and that of belite was 20~80 ${\mu}m$. This result thought to be attributed low $Al_2O_3$ content and cooling condition. Interstitial phase increased with blast furnace slag content and gehlenite was formed by the condition of LSF and SM. So raw mix with 27~41% blast furnace slag could be converted into cement clinker by appropriate choice of melting andcooling methods in this study.

부유물질의 응접작용 및 침전특성에 관한 실험적 연구

추용식,박용안,이희준,박광순,권수재,Chu, Yong-Shik,Park, Yong-Ahn,Lee, Hee-Jun,Park, Kwang-Soon,Kweon, Su-Jae 한국해양학회 1999 바다 Vol.4 No.1

염분도, 부유물질의 농도, 난류의 세기 및 점토광물의 함량이 세립질 부유물질의 응집과 침전특성에 미치는 효과를 규명하기 위하여 수조실험을 실시하였다. 염분도, 부유물질의 초기농도($C_o$) 그리고 난류의 세기를 변화시켜면서 시간에 따른 농도 및 침전속도의 변화를 관찰하였으며, 동시에 수조의 저층에서 일정간격으로 부유물질을 채취하여 입도분석 및 점토광물의 함량비 변화와 업자 덩어리(floc)의 형성과정을 관찰하였다. 일정한 부유물질의 $C_o$ 상태에서 염분도의 증가에 따라 중앙침전속도($W_{50}$)는 선형적언 증가를 보였다. 해수상태(33‰)에서 농도변화에 따른 침전특성은 $C_o$ 범위에 따라 3가지 경우로 다르게 나타났다. 200 mg/l 이하의 범위에서는 농도변화에 따른 침전속도의 변화가 거의 일어나지 않았으며, 200~13,000 mg/l 범위에서는 '$W_{50}=0.45C^{0.44}$' 의 상호관계식에 따라($W_{50}$이 농도의 증가에 비례하며 가속화되었다. 한편, 13,000 mg/l 이상의 높은 농도 범위에서는 농도가 증가할수록 침전속도는 오히려 감소함을 보였다. 난류의 세기가 부유물질의 침전과정에 마치는 영향은 부유물질의 농도에 따라 다르게 나타났다. 상대적으로 부유물질의 농도가 낮아(500 mg/l) 입자간의 상호간섭이 활발하지 않은 상태에서는 난류의 발생은 업자간의 충돌기회를 증가시켜 응집작용과 침전을 촉진시키는 한편, 자연적으로 입자간의 충돌이 충분히 이루어지는 높은 농도(800 mg/l)에서는 난류의 발생은 오히려 상호 입자간의 분산과 간섭침전(hindered settling)을 일으켜 침전을 지연시켰다. 부동 유체 및 난류 발생 상태에서 모두 시간이 경과함에 따라 부유물질의 입도분급이 일어나며 입도분포의 왜도는 감소하고 첨도는 증가하였다. 점토광물중에서 스멕타이트가 가장 빨리 침전되는 반면, 일라이트가 가장 느린 침전속도를 보였다. A laboratory flume experiment, using turbulence-generating acryl tank and natural sediments, was conducted to investigate the effects of salinity, concentration of suspended sediment, turbulence and clay minerals on the flocculation and settling of fine-grained suspended sediments. While experiments were run, a sequence of water samples were taken near the bottom of the tank to analyze the variations of size distribution and relative contents of clay minerals. The results of the salinity experiment indicate that median settling velocity ($W_{50}$) increases linearly with salinity. Different settling processes of suspended sediments under variable concentrations appear to be predictable, depending upon the range of the suspension concentration. At concentrations less than 200 mg/l, $W_{50}$ is rarely varied with concentration probably because of the individual--grain settling mode. In the range of 200 to 13,000 mg/l show $W_{50}$ and concentration a good relationship following an empirical formula: $W_{50}=0.45C^{0.44}$. This relationship, however, no longer holds in concentrations exceeding 13,000 mg/l; instead, a more or less reverse one is shown. This result suggests an effect of hindered settling. The turbulence effect is somewhat different from that of concentration. Turbulence accelerates the flocculation and settling susepended sediments at low concentration (200 mg/l), whereas at high concentration turbulence breaks floes down and impedes the settling. Size distribution of suspended sediments sampled near the bottom of the tank tend to be more negatively skewed and leptokurtic in turbulent conditions compared to those in static conditions. The clay mineral analysis from the sequential water samples shows that over time the content of smectite decreases most rapidly with illite remaining concentrated in suspension. This means that smectite, among other clay minerals, plays the most effective role in the flocculation of fine-grained sediment in saline water.

성형체의 대기시간에 따른 ALC 표면 색상과 결정특성

추용식,서성관,박수현,송훈,이종규 한국세라믹학회 2012 한국세라믹학회지 Vol.49 No.6

ALC was fabricated using cement, lime, quartzite and a foaming agent via a hydrothermal reaction. ALC has various hydrothermal reaction products and many pores. The properties and colors of ALC surfaces were changed by various factors during ALC fabrication process. This study tested various staying times to analyze these phenomena. It was found that the staying time of green body influenced the properties of hydrothermal products and color of ALC surface. The longer staying time of green body, the lower tobermorite content and cumulative loss weight. An increase in holding time changed color and decreased whiteness of ALC surface. The relationship between whiteness and cumulative loss weight was very high (Coefficient, r = 0.95). It was surmised that tobermorite content was an important factor for enhancement of whiteness However, ettringite and quartzite did not contribute to whiteness.

시멘트 경화체의 강도특성에 미치는 혼합재료의 영향

추용식,김정환 한국세라믹학회 1994 한국세라믹학회지 Vol.31 No.12

DSP technique was applied to improve the high strength characteristics of hardened cement paste using pozzolan materials as blending materials, and pozzolan reactivity was investigated. Pozzolanic materials such as diatomaceous earth, fly ash and hydrated silica were used as blending material. And also superplasticizer was added to cement for molding the specimens. After curing for 60 days, the specimens substituted with 10 and 15 wt% of diatomaceous earth showed better strength characteristics than the specimen with fly ash. The specimen substituted 7 wt.% of hydrated silica exhibited excellent strength with above 800 kg/$\textrm{cm}^2$.

C12A7계 슬래그와 석유 코크스 연소재를 사용한 수축저감재 및 모르타르의 특성

추용식,박수현,서성관,박재완 한국세라믹학회 2013 한국세라믹학회지 Vol.50 No.5

In this study, petroleum cokes ash and C12A7-based slag were used for the shrinkage reduction and strength enhancement of mortar. The hydration properties of shrinkage reduction agents were analysed. The flow, change of length and compressive strength were experimented with mortar-added shrinkage reduction agents. As a result of this study, petroleum cokes ash : C12A7-based slag =60 ~ 80% : 20 ~ 40% showed excellent results. In the case of mortar with 20% C12A7-based slag, the setting time and change of length were similar to Ref. mortar. The flow and compressive strength were superior to Ref. mortar. In the case of mortar with a 40% C12A7-based slag, the setting time was longer than Ref. mortar. The compressive strength of 3 days and 7 days were superior to Ref. mortar.

규석 분말도에 따른 ALC의 물리적 특성 변화

추용식,정의종,송훈,이종규,김영곤,강대구,Chu, Yong-Sik,Jung, Ui-Jong,Song, Hun,Lee, Jong-Kyu,Kim, Young-Gon,Kang, Dae-Gu 한국세라믹학회 2010 한국세라믹학회지 Vol.47 No.5

ALC was fabricated using cement, lime and quartzite by hydrothermal reaction. ALC has low strength and brittleness on account of inner pores. The studies for resolving these problems were driven by many researchers. Among these researches, the controls of quartzite fineness have been studied for unsuitable properties of ALC. This study experimented with variation of 90 ${\mu}m$ residue for obtain good physical properties. It was found that 90 ${\mu}m$ residue influenced on physical properties of ALC. The lower amount of 90 ${\mu}m$ residue, the higher compressive and bending strength. But the continuing decrease of 90 ${\mu}m$ residue did not cause the increase of strength. In order to application of these results in process, the states of process and hydrothermal products will be considered.

시멘트 대체재로의 제지애쉬 적용가능성 고찰

추용식,Chu, Yong-Sik 한국건설순환자원학회 2016 한국건설순환자원학회지 Vol.11 No.2

유리연마슬러지를 사용한 경량골재 제조 및 골재의 내부기공이 물성에 미치는 영향에 관한 연구

추용식,이종규,심광보,Chu, Yong-Sik,Lee, Jong-Kyu,Shim, Kwang-Bo 한국세라믹학회 2005 한국세라믹학회지 Vol.42 No.1

유리연마슬러지와 graphite를 발포제로 사용하여 경량골재를 제조하였으며, 경량골재 내부기공과 물성과의 상관성을 도출하였다. 이때 graphite 함량을 각각 달리하여 성구를 제조하였으며, $700^{circ}C$ 및 $800^{circ}C$에서 20분 동안 소성하였다. 소성 전후 골제의 부피 변화를 검토한 결과, 발포제의 첨가량보다는 소성 온도가 즘 더 큰 영향을 미침을 확인하였다 기공의 크기 및 면적은 발포제 첨가량과 소성 온도 상승에 따라 증가하는 특징을 나타내었으나, 발포제 첨가량 $1\%$ 이상에서는 큰 폭의 증가를 동반하지 않았다. 흡수율/열전도율과 기공과의 상관성은 매우 높아, 각각의 상관관계계수는 $0.8\pm$ 이상을 나타내었다. Lightweight aggregate was made using glass abrasive sludge and graphite in this study. This study tried to draw the correlation between lightweight aggregate's properties and internal pore. The precursor was made by added different graphite contents and was burned for 20 min. at $700^{circ}C$ and $800^{circ}C$. The volume change of aggregate was checked at before and after homing, and confirmed that the homing temperature effected more than expanding agent on volume change. The size and area of pore in aggregate increased according to the amount of expanding agent and homing temperature but it didn't bring about big effect above $1\%$ of expanding agent. The absorbtion ratio, thermal conductivity and porosity have a high correlation, so each coefficient of correlation showed above $0.8\pm$.

실험실적 소성조건에 따른 클린커 광물의 특성변화 및 현장 클린커 고찰

추용식,김인섭,권춘우,이종규,권우택,김수룡,김병익 한국시멘트협회 2004 시멘트 심포지움 Vol.31 No.-