Research on Slaked Magnesium Slag as a Raw Material and Blend for Portland Cement

2011 ◽  
Vol 335-336 ◽  
pp. 1246-1249 ◽  
Author(s):  
Ji Wei Cai ◽  
Guang Liang Gao ◽  
Rui Ying Bai ◽  
Feng Lu ◽  
Ling Li
Keyword(s):  
Portland Cement ◽  
Raw Material ◽  
Dust Pollution ◽  
Binary Blends ◽  
Cement Pastes ◽  
Magnesium Metal ◽  
Granulated Blast Furnace Slag ◽  
Furnace Slag

The magnesium slag is discarded from production of magnesium metal from dolomite. However the magnesium slag is slaked in some factories by means of sprinkling water to prevent from dust pollution. The possibility of slaked magnesium slag (SMS) to play a role of raw material and blend for portland cement was investigated by experiments of raw mix preparation, clinker calcining and property determination of cement pastes and mortars. The results revealed that SMS was still reactive. The raw mix with SMS was of excellent burnability that would contribute to energy saving. As a raw material, SMS can be used for calcining clinker of good quality; and as a blend it is suitable for production of ordinary portland cements. Because the magnesium slag is slaked, SMS has no problem on soundness. Higher strength of cement can be obtained in form of binary blends consisting of SMS and ground granulated blast-furnace slag or fly ash.

Research on Slaked Magnesium Slag as a Mineral Admixture for Concrete

2011 ◽  
Vol 287-290 ◽  
pp. 922-925 ◽  
Author(s):  
Ji Wei Cai ◽  
Guang Liang Gao ◽  
Rui Ying Bai ◽  
Li Xue Yu ◽  
Shao Jun Wang
Keyword(s):  
Blast Furnace ◽  
Blast Furnace Slag ◽  
Mineral Admixture ◽  
Reactivity Index ◽  
Ternary Blend ◽  
Dust Pollution ◽  
Magnesium Metal ◽  
Granulated Blast Furnace Slag ◽  
Furnace Slag

The magnesium slag is discarded from production of magnesium metal from dolomite. However the magnesium slag is slaked in some factories by means of sprinkling water to prevent from dust pollution. The possibility of slaked magnesium slag (SMS) to play a role of mineral admixture for concrete was investigated by experiments of mortars and concretes prepared with SMS. The results revealed that SMS was still reactive. When SMS is substituted for 30% of cement, its reactivity index is equivalent to that of grade I fly ash (FA). And when SMS is used as mineral admixture to prepare concrete, it contributes to strength of concrete no less than S95 ground granulated blast-furnace slag (GGBS). Better effect of binary or ternary blend can be obtained by combining SMS with GGBS and/or FA. Because the magnesium slag is slaked, SMS has no problem on soundness, so it can be applied in concrete as mineral admixture.

Calorimetric determination of the effect of additives on cement hydration process

2013 ◽  
Vol 67 (2) ◽  
Author(s):  
Pavel Šiler ◽  
Josef Krátký ◽  
Iva Kolářová ◽  
Jaromír Havlica ◽  
Jiří Brandštetr
Keyword(s):  
Portland Cement ◽  
Silica Fume ◽  
Maximum Temperature ◽  
Granulated Blast Furnace Slag ◽  
Mineral Components ◽  
Maximum Temperatures ◽  
The Impact ◽  
Furnace Slag ◽  
Calorimetric Determination

AbstractPossibilities of a multicell isoperibolic-semiadiabatic calorimeter application for the measurement of hydration heat and maximum temperature reached in mixtures of various compositions during their setting and early stages of hardening are presented. Measurements were aimed to determine the impact of selected components’ content on the course of ordinary Portland cement (OPC) hydration. The following components were selected for the determination of the hydration behaviour in mixtures: very finely ground granulated blast furnace slag (GBFS), silica fume (microsilica, SF), finely ground quartz sand (FGQ), and calcined bauxite (CB). A commercial polycarboxylate type superplasticizer was also added to the selected mixtures. All maximum temperatures measured for selected mineral components were lower than that reached for cement. The maximum temperature increased with the decreasing amount of components in the mixture for all components except for silica fume. For all components, except for CB, the values of total released heat were higher than those for pure Portland cement samples.

Alkaline Activation of Kaolinitic Soils for the Production of Special Binders

2005 ◽  
Vol 498-499 ◽  
pp. 394-400
Author(s):  
D.P. Dias ◽  
Amilcar Soares ◽  
C.E. Viana ◽  
J.C. Soares ◽  
P.H.B. Azevedo
Keyword(s):  
Portland Cement ◽  
Mechanical Strength ◽  
Raw Material ◽  
Experimental Program ◽  
Alkaline Activation ◽  
Granulated Blast Furnace Slag ◽  
Suitable Combination ◽  
Furnace Slag ◽  
Grinding Time ◽  
Alkali Activated

The alkaline activation of Portland cement based materials, ground granulated blast furnace slag and pozzolans has been accomplished with success since the decade of 40, in several countries. The practicability of the use of the alkalis opens new opportunities for the production of special binders with properties different from those presented by the ordinary Portland cement. Besides the chemical composition, the mechanical strength of these alkali-activated materials depends a lot on the reactivity of the raw material, property that is influenced mainly by the specific surface area and crystalline degree of the raw material. Thus, an experimental program was carried out aiming at evaluating the influence of these variables in the compressive strength, at 3, 7 and 28 days of age, for mortars manufactured using alkaline activation of kaolinitic soils. The results have shown that the most suitable combination, in terms of mechanical strength and economy of energy, was the mortar manufactured with soil receiving a ½ hour grinding time and calcined at 650oC during four hours.

scholarly journals Surface Characteristics of Portland Cement/Blast Furnace Slag Mixtures

1996 ◽  
Vol 13 (6) ◽  
pp. 461-467 ◽  
Author(s):  
Kh.A. Khalil
Keyword(s):  
Blast Furnace ◽  
Portland Cement ◽  
Blast Furnace Slag ◽  
Surface Characteristics ◽  
Hydration Products ◽  
Cement Pastes ◽  
Degree Of Hydration ◽  
Granulated Blast Furnace Slag ◽  
Granulated Slag ◽  
Furnace Slag

The effect of the degree of hydration and amounts of granulated blast furnace slag on the surface properties of Portland cement pastes were studied. The results obtained showed that the specific surface area SBET (m2/g) and pore volume Vp (cm3/g) decreased on increasing the degree of hydration. The addition of different amounts of granulated slag effected a decrease in SBET and Vp to an extent proportional to the amount present. These results were attributed to a replacement of clinker by the amounts of slag added and the formation of hydration products.

scholarly journals Optimizing Mixtures of Alkali Aluminosilicate Cement Based on Ternary By-Products

2021 ◽  
Vol 7 (7) ◽  
pp. 1264-1274
Author(s):  
Hoang Vinh Long
Keyword(s):  
Compressive Strength ◽  
Fly Ash ◽  
Portland Cement ◽  
Raw Materials ◽  
Setting Time ◽  
Raw Material ◽  
Optimal Composition ◽  
Granulated Blast Furnace Slag ◽  
Furnace Slag ◽  
By Products

Portland cement is a popular binder but causes many adverse effects on the environment. That is due to the large consumption of raw materials and energy during production while emitting vast amounts of CO2. In recent years, Alkali Aluminosilicate Cement (AAC) has drawn much attention in research and development and promises to become a binder that can replace the traditional cement. In many studies of this binder, the content of the ingredients is often gradually changed to determine the optimal composition. The object of this paper is to optimize the composition of AAC using a combination of three by-products as the primary raw material, including Rush Husk Ash (RHA), Fly Ash (FA), and Ground Granulated Blast-Furnace Slag (GGBS). The investigation was conducted based on the critical parameter SiO2/Al2O3, and the D-optimal design. The FA and the GGBS were industrial product form, while the RHA was ground in a ball mill for 2 hours before mixing. The results show that this type of binder has setting time and soundness to meet standard cement requirements. While comparing to Portland cement, the AAC has a faster setting time, slower development of compressive strength in the early stages but a higher strength at the age of 56 days. According to the highest compressive strength at 28 days and high fly ash content, the optimal composition was RHA of 27.8%, FA of 41.8%, and GGBS of 15.4%, corresponding to the ratio SiO2/Al2O3 of 3.83. In addition, compressive strength at 28 days of the mortar specimens with the optimal binder and the ratio of water/ cement at 0.32 reached 63 MPa. Doi: 10.28991/cej-2021-03091724 Full Text: PDF

scholarly journals MICRO-MECHANICAL PROPERTIES OF CEMENT AND SLAG COMPOSITES MEASURED BY NANOINDENTATION

2020 ◽  
Vol 26 ◽  
pp. 45-49
Author(s):  
Jiří Němeček ◽  
Jiří Němeček
Keyword(s):  
Mechanical Properties ◽  
Portland Cement ◽  
Modulus Of Elasticity ◽  
Volume Fraction ◽  
Blended Cement ◽  
Hydration Products ◽  
Granulated Blast Furnace Slag ◽  
The Difference ◽  
Portland Cement Paste ◽  
Furnace Slag

In this study, the micromechanical response of two cementitious composites was characterized by nanoindentation. Pure Portland cement paste and Portland cement with 50 vol. % replaced with granulated blast furnace slag (GBFS) paste were investigated at the age of 28 days. Grid nanoindentation, statistical deconvolution and scanning electron microscopy were used to characterize the main hydration products. Several grids with approximately 500 indents on each sample were performed to obtain modulus of elasticity, hardness and creep indentation parameter. Similar mechanical phases containing calcium silica hydrate, crystalline calcium hydroxide and un-hydrated clinker were found in both samples varying by volume fraction. Blended cement, moreover, contains a phase of slag hydration products with a significantly lower modulus of elasticity. This phase with a high portion of unreacted GBFS is mostly responsible for the difference of mechanical properties of the whole composite.

Pore Structure, Permeability, And Chloride Diffusion In Fly Ash-And Slag-Containing Pastes And Mortars

1988 ◽  
Vol 137 ◽  
Author(s):  
R. I. A. Malek ◽  
D. M. Roy ◽  
Y. Fang
Keyword(s):  
Chloride Diffusion ◽  
Fly Ashes ◽  
Chloride Permeability ◽  
Cement Pastes ◽  
Granulated Blast Furnace Slag ◽  
Transport Of Ions ◽  
Diffusion Rates ◽  
Different Sources ◽  
Limiting Value

AbstractThe transport of ions through cement pastes and mortars with variable contents of fly ashes and granulated blast-furnace slag from different sources and with variable composition has been investigated. The research included the determination of chloride diffusion rate and chloride permeability in relation to microstructure development. The median pore size generally was much diminished in mature blended material compared with Portland cement (PC) pastes and mortars. It appears that, at the same age, a finer microstructure is generally developed in blended specimens compared to PC specimens. Also, it was found that the microstructure approaches a limiting value at longer ages of hydration. That limiting value may be reached at earlier ages with the blends. The chloride diffusion rates and permeabilities in the blends were significantly lower than PC mixes. A comparison between the blends containing fly ashes and those containing slag was made.

scholarly journals Protective Geopolymer Coatings Containing Multi-Componential Precursors: Preparation and Basic Properties Characterization

Materials ◽  
2020 ◽  
Vol 13 (16) ◽  
pp. 3448
Author(s):  
Chenhui Jiang ◽  
Aiying Wang ◽  
Xufan Bao ◽  
Zefeng Chen ◽  
Tongyuan Ni ◽  
...  
Keyword(s):  
Compressive Strength ◽  
Blast Furnace ◽  
Fly Ash ◽  
Portland Cement ◽  
Adhesive Strength ◽  
Blast Furnace Slag ◽  
Setting Time ◽  
Rapid Test ◽  
Granulated Blast Furnace Slag ◽  
Furnace Slag

This paper presents an experimental investigation on geopolymer coatings (GPC) in terms of surface protection of civil structures. The GPC mixtures were prepared with a quadruple precursor simultaneously containing fly ash (FA), ground granulated blast-furnace slag (GBFS), metakaolin (MK), and Portland cement (OPC). Setting time, compressive along with adhesive strength and permeability, were tested and interpreted from a perspective of potential applications. The preferred GPC with favorable setting time (not shorter than 120 min) and desirable compressive strength (not lower than 35 MPa) was selected from 85 mixture formulations. The results indicate that balancing strength and setting behavior is viable with the aid of the multi-componential precursor and the mixture design based on total molar ratios of key oxides or chemical elements. Adhesive strength of the optimized GPC mixtures was ranged from 1.5 to 3.4 MPa. The induced charge passed based on a rapid test of coated concrete specimens with the preferred GPC was 30% lower than that of the uncoated ones. Setting time of GPC was positively correlated with η[Si/(Na+Al)]. An abrupt increase of setting time occurred when the molar ratio was greater than 1.1. Compressive strength of GPC was positively affected by mass contents of ground granulated blast furnace slag, metakaolin and ordinary Portland cement, and was negatively affected by mass content of fly ash, respectively. Sustained seawater immersion impaired the strength of GPC to a negligible extent. Overall, GPC potentially serves a double purpose of satisfying the usage requirements and achieving a cleaner future.

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