Recent Advances in Understanding Physical Properties of Metallurgical Slags

민동준,Fumitaka Tsukihashi 대한금속·재료학회 2017 METALS AND MATERIALS International Vol.23 No.1

Present-day knowledge of the structure and physical properties of metallurgical slags is summarized to address structure-property and inter-property relationships. Physical properties of slags including viscosity, electrical conductivity, and surface tension is reviewed focusing on the effect of slag structure, which is comprehensively evaluated using FT-IT, Raman, and MAS-NMR spectroscopy. The effect of the slag composition on slag structure and property is reviewed in detail: Compositional effect encompasses traditional concepts of basicity, network-forming behaviors of anions, and secondary impact of network-modifying cations. Secondary objective of this review is elucidating the mutual relationship between physical properties of slags. For instance, the relationship between slag viscosity and electrical conductivity is suggested by Walden’s rule and discussed based on the experimental results. Slag foaming index is also introduced as a comprehensive understanding method of physical properties of slags. The dimensional analysis was made to address the effect of viscosity, density, and surface tension on the foaming index of slags.

스테인리스 스틸 AOD 슬래그를 이용한 폼 콘크리트의 탄소포집 성능

김병준,유성원,최영철 한국구조물진단유지관리공학회 2020 한국구조물진단유지관리공학회 논문집 Vol.24 No.4

The purpose of this study is to investigate the mechanical and carbon-capture properties of foam concrete containing stainless steelargon oxygen decarbonization(AOD) slag. AOD slag was used as a binder, and foam concrete having a foaming ratio of 69 ± 0.5 % and a slurrydensity of 573.2 to 578.6 kg / m3 was produced. In order to examine the effect of carbonation, blended specimen was cured by two types : normalcuring and CO2 curing. As a result of the experiment, the specimens incorporating AOD slag showed higher compressive strength than Plainafter CO2 curing. According to the analysis of the image of foam concrete, it was confirmed that the ST30 has a lower total pore volume andaverage pore size than plain, resulting in high compressive strength. The SEM analysis confirmed the formation of calcite by carbonation ofAOD slag. Through the thermogravimetric analysis, the increase of CO2 uptake was confirmed by the incorporation of AOD slag. Foam concretehas a higher porosity than normal concrete, so it is expected that carbon-capture performance can be improved by using a AOD slag. 본 연구에서는 스테인리스 스틸 AOD 슬래그를 이용한 폼 콘크리트의 역학적 및 탄소포집 성능을 조사하였다. AOD 슬래그바인더로 사용하며 기포율이 69 ± 0.5%이고, 슬러리 밀도는 573.2 ~ 578.6 kg/m3인 폼 콘크리트를 제작하였다. 탄산화에 의한 영향을 살펴보기 위해 배합을 마친 폼 콘크리트는 일반 양생 및 탄산화 양생 두 가지로 하였다. 압축강도 측정결과 Plain 시편에 비해 AOD 슬래그를 30% 치환한 ST30 시편은 탄산화 양생에 따라 강도가 증가하였다. 폼 콘크리트의 이미지 분석결과에서도 ST30시편이 Plain시편 보다공극률이 낮으며 평균 공극 크기도 작아 압축강도가 높음을 확인할 수 있었다. 또한 SEM 분석을 통하여 AOD 슬래그의 탄산화에 의한탄산칼슘의 생성을 확인하였다. TGA분석을 통해 AOD 슬래그의 혼입으로 CO2 uptake의 증가를 확인하였다. 폼 콘크리트는 일반 콘크리트에 비해 공극률이 높으므로 AOD 슬래그를 이용하면 탄산화 속도가 빨라 탄소 포집 성능 향상을 기대할 수 있을 것으로 판단된다.

지오폴리머 폼블록 제조 시 용융슬래그와 소각비산재의 첨가영향

오아람,손해준,고아람,이우근 한국폐기물자원순환학회 2014 한국폐기물자원순환학회지 Vol.31 No.3

Geopolymer foam block was prepared and its characteristics discussed to evaluate the possibility of replacing blastfurnace slag (below BFS) with melting slag in this study. 10~20wt% of BFS was replaced with melting slag. And also10wt% of mine tailing was replaced with fly ash discharged from municipal solid waste incinerator (below MSWI). Thecompressive strength of foam block prepared was similar to that of foam block prepared without replacing BFS. Andalso it was increased by replacing 10wt% of mine tailing with MSWI fly ash. Considering these results, melting slagmay be used instead of BFS without damaging the quality of foam block.

골재종류 및 기포도입율 변화에 화에 따른 경량기포 콘크리트의 기초적 특성

황김광 ( Jin Guang Huang ),김대건 ( Jae Yong Park ),문경식 ( Sang Woon Jung ),정광복 ( Kwang Bok Jeung ),한민철 ( Min Cheol Han ),한천구 ( Cheon Goo Han ) 한국건축시공학회 2014 한국건축시공학회 학술발표대회 논문집 Vol.14 No.1

In this study, high volume of industrial by-products including blast furnace slag, recycled aggregate powder and incineration ash have been utilized on the slurry of the foamed lightweight concrete. As to decrease the price of the lightweight foam concrete, mortar based slurry and concrete based slurry has been fixed. As the variation of the foam conduction ratio and aggregates, the foam ratio and compressive strength has been tested. Results showed that using recycled aggregates in the slurry showed better effect than using natural aggregates due to the alkali properties of the recycled aggregates could activate the potential hydraulic properties of the blast furnace slag. Consider about the low price of the recycled aggregates, it could be identified that using recycled aggregates in high volume blast furnace slag blended lightweight concrete showed better compressive strength than natural aggregates.

Prediction of electromagnetic transmission properties using dielectric property modeling of foamed concrete containing BFS

Cho, Sung-Sil,Yoo, Jae-Sung,Kim, Jin-Man,Hong, Ic-Pyo Elsevier BV 2017 Construction and Building Materials Vol.151 No.-

<P><B>Abstract</B></P> <P>In this paper, we propose a formula for modeling dielectric properties for evaluating the electromagnetic transmission of foamed concrete (FC) widely used as building materials. This includes the effective permittivity and loss tangent according to the foam content of FC mixes containing blast furnace slag (BFS), as well as the content of the BFS, by modifying the dielectric modeling formula for porous foam materials. The difference between the permittivity calculated using the proposed modeling formula and the actual measured permittivity ranges from 0.2% to 2.6%. The calculated result and the measured value are approximately the same. The transmission properties of FC were calculated using the calculated dielectric property values. FC samples containing BFS were fabricated using different foam and BFS content, and their transmission properties were measured, the results of which coincided well with the simulation results. Therefore, the accuracy of the proposed dielectric property modeling of FC containing BFS was verified.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Modeling formula for predicting the permittivity and loss tangent of FC containing BFS. </LI> <LI> Electromagnetic transmission properties of FC containing BFS were simulated and measured. </LI> <LI> Predict the electromagnetic transmission properties of an interior space that has applied FC containing BFS. </LI> </UL> </P>

Fabrication and characterization of a novel foam ceramic material based on coal gasification slags

Hudie Yuan,Hongfeng Yin,Yun Tang,Yalou Xin,Xilou Pu,Hao Zhang 한양대학교 세라믹연구소 2020 Journal of Ceramic Processing Research Vol.21 No.6

In this paper, the feasibility of recycling coal gasification slag by high temperature foaming process to fabricate foal ceramicinsulation board has been investigated. Silicon carbide (SiC) was added as the foam agent, and the foaming mechanism wasalso discussed. The results showed that utilization rate of the coal gasification prepared to the foam ceramic new wall materialwas up to 77% and the best dosage of SiC was 3%. Moreover, the relatively optimum parameters were obtained at thesintering temperature of 1,160 ºC for 3h with 77% slags, 20% clay and 3% SiC. Furthermore, compression strength reaches1.18 MPa, the bulk density and heat conductivity coefficient value are 0.21 g/cm3 and 0.05 W/(m·k), respectively.

고로슬래그 미분말을 혼입한 기포콘크리트의 물리적 특성

조은석 ( Cho Eun-seok ),임정준 ( Lim Jeong-jun ),송하영 ( Song Ha-young ),이상수 ( Lee Sang-soo ) 한국건축시공학회 2019 한국건축시공학회 학술발표대회 논문집 Vol.19 No.2

Light-weight foamed concrete using cement as a raw material consumes a lot of energy and generates CO2 because of the high temperature firing process in the manufacturing process of cement. This study was carried out to evaluate the use of blast furnace slag through the properties analysis by substituting a certain amount of blast furnace slag as an industrial by-product as a substitute for cement. The experimental results showed similar characteristics to those of using only cement when the blast furnace slag fine powder was used in an appropriate amount. Therefore, if a certain amount of cement is replaced with blast furnace slag powder, it can maintain similar quality, reduce natural resources and energy consumption, and reduce carbon dioxide emissions.

폐스티로폼과 조강시멘트를 혼입한 경량기포콘크리트의 특성

박채울 ( Park Chae-wool ),이상수 ( Lee Sang-soo ) 한국건축시공학회 2020 한국건축시공학회 학술발표대회 논문집 Vol.20 No.1

In Korea, more than 30,000 tons of waste Styrofoam are produced every year. Styrofoam is spent more than 500 years decomposing during the reclamation process, so it needs to be recycled. The recycling rate of waste styrofoam continues to be the third highest in the world, but it is lower than that of Germany and Japan. Therefore, measures are needed to increase the recycling rate of waste Styropol. Another problem is that cement is mainly used in existing lightweight foam concrete. However, large amounts of CO2 from cement-producing processes cause environmental pollution. Currently, Korea is increasing its greenhouse gas reduction targets to cope with energy depletion and climate change, and accelerating efforts to identify and implement reduction measures for each sector. In 2013 alone, about 600 million tons of carbon dioxide was generated in the cement industry. Therefore, this study replaces CO2 generation cement with furnace slag fine powder, uses crude steel cement for initial strength development of bubble concrete, and manufactures hardening materials to study its properties using waste styrofoam. As a result of the experiment, the hardening agent replaced by micro powder of furnace slag was less intense and more prone to absorption than cement using ordinary cement. Further experiments on the segmentation and strength replenishment of furnace slag are believed to contribute to the manufacture of environmentally friendly lightweight foam concrete.

고로슬래그 혼입율에 따른 CA계 기포콘크리트의 강도특성

유재성 ( Yu Jae-seong ),최선미 ( Choi Sun-mi ),최홍범 ( Choi Hong-bum ),이무 ( Li Mao ),김진만 ( Kim Jin-man ) 한국건축시공학회 2016 한국건축시공학회 학술발표대회 논문집 Vol.16 No.2

The aim of this research was evaluating strength characteristics of foamed concrete using Ladle Furnace slag with GGBFs. For all mixtures, because of the early setting and strength development, it was possible to deform the formwork and measure the compressive strength within 3 hours.

팽창성 균열저감제를 이용한 고로슬래그 미분말 기반 경량기포 콘크리트의 특성 및 목업실험

한상윤,한민철 한국건축시공학회 2017 한국건축시공학회지 Vol.17 No.6

This study is to develop a high quality lightweight foamed concrete that can be applied in the field using EXFG bycracking reducing agent combined with FGD and ALS. First, to increase the volume of foam, the flow and density of themixture was increased and decreased, respectively. At this time, the effect of substitution ratio of EXFG on fluidity wasnegligible. The fraction of foam was the highest at EXFG 1%, and the settlement was found to be prevented by theexpansion reaction at EXFG 1%. At this time, the ratio of foam was 65%. In the compressive strength, the strengths weresimilar or decreased when the substitution ratio of EXFG was more than 1%. The apparent density satisfied the KS 0.5type at the bubble contents was 65%. In case of EXFG substitution, dry shrinkage was decreased by about 10%. As thesubstitution ratio of EXFG increased, the thermal conductivity increased proportionally. 본 연구는 EXFG를 활용하여 실제 현장 적용이 가능한고품질의 경량기포콘크리트를 개발하고자 하였는데, 그 결과를 요약하면 다음과 같다. 먼저, 기포혼입율이 증가할수록 플로치도 증가하였으며,반대로 기포슬러리 밀도는 감소하는 것으로 나타났다. 이때,EXFG의 치환율이 유동성에 미치는 영향은 미미한 것으로나타났다. 기포율은 EXFG 1%에서 가장 높은 기포율을 나타냈으며, 침하깊이 역시 EXFG 1% 치환 시 팽창반응에의해 침하가 방지되는 것으로 나타났다. 이때 기포혼입율은65% 가 적정한 것으로 나타났다. 압축강도의 경우 EXFG의 치환율이 1% 이상일 때 강도는유사하거나 오히려 감소하는 경향을 나타냈으며, 겉보기 밀도는 기포혼입율 65%에서 KS 0.5품 기준을 만족하였다. 건초수축길이변화율의 경우 EXFG를 치환한 경우 이를 사용하지 않는 배합 대비 건조수축일이변화율이 약 10% 이상감소하는 것으로 나타났으며, EXFG의 치환율이 증가 할수록 열전도율도 비례하게 높아지는 것으로 나타났다. 한편, Mock-up 실험에서 균열발생의 경우 EXFG-1의경우 기존기술 및 OPC 배합대비 약 50% 이상 균열이 저감되는 효과를 나타냈다.