6.3.1 Compaction Characteristics and Hydraulic Conductivity (K) of Bauxite Residue. The compaction properties of a material depend on the type of compaction, grain size distribution and water. ... U. M. (2020). Correlation studies on geotechnical properties of various industrial byproducts generated from thermal power …
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When the addition of low-grade raw bauxite was 34.5%, the compressive strength of the refractories treated at 1600°C was up to 104.3 MPa, and its thermal conductivity tested at 1000°C was only 1 ...
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thermal shock cycles with the help of the addition of the second phase. Besides, the improvement of thermal conductivity is limited to 1.5-2.3 W·(m·K)-1, which is mainly resulted from low thermal conductivity of the second phase and the negative effect of excessive liquid phase. As a result, introducing different reinforcements
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where k is the thermal conductivity, A is the cross-sectional area, ΔT is the temperature difference, and L is the length of the heat transfer pathway, which is referred to herein and after, as "length"; subscript e refers to the effective thermal conductivity.. In the case of the classical parallel model, the temperature across the porous medium (ΔT), …
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The thermal conductivity was decreased with porosity increases from 0.5 to 0.4 W/m K for bauxite additions and to 0.36 W/m K for metakaolin additions. The effect …
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The thermal conductivity of the bulk is one of the determining factors for the thermal performance of a heat exchanger for thermal charging or discharging of the bulk [15]. Knowledge of this bulk parameter is therefore crucial for its design. ... (<0.1 €/kg) but has some drawbacks regarding thermal cycling. Bauxite (approximately 1 €/kg ...
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For the energy‐saving and safe utilization of industrial furnaces, it is essential to develop refractories with low thermal conductivity and high strength. In this study, low‐grade bauxite and coal gangue were used as the main raw materials to prepare microporous mullite refractories with low thermal conductivity and high strength by the …
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@article{Chen2022InfluencingFO, title={Influencing factors of mechanical and thermal conductivity of ed phosphogypsum-based composite cementitious materials}, author={Mingsheng Chen and Peng Liu and Dewen Kong and Yi Wang and Jingdong Wang and Yansen Huang and Ke Yu and Ningbo Wu}, journal={Construction …
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a low thermal conductivity within the limits of thermal insulation material (less t han 0.5 W/m K); it was done b y controlling the porosity which reached a maximum value appro ximately 25%.
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FRACTURE CONDUCTIVITY OF A BAUXITE-PROPPED GEOTHERMAL SYSTEM AT IN-SITU CONDITIONS Trevor Stoddard1, John McLennan1,2, Joseph Moore2 1. Department of Chemical Engineering, University of Utah ... of thermal expansion, when compared to the confining pressure is assumed to be negligible) or the order in which the tests were run. …
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Thermal conductivity results of deionized The thermal conductivities of the water and bauxite nanofluid were measured as 0.59 W/m. K and 0.64 W/m. K, respectively at 50 W heating power and 66 g/s ...
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At high temperatures of 200–800 °C, the thermal conductivity of more than 60% of the modified pearlescent sand–bauxite castable was smaller than that of conventional bauxite castable. The addition of the modified pearlescent sand can greatly reduce the thermal conductivity and bulk density of bauxite castable.
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Thermal behavior of three characteristic samples from the lower bauxite horizon from locality of Atalandi, Locrida area (Greece) was investigated in the …
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In this study, low-grade bauxite and coal gangue were used as the main raw materials to prepare microporous mullite refractories with low thermal conductivity and high strength by the in situ decomposition method. The effect of coal gangue content and sintering temperature on the structure and properties of mullite refractories was also ...
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The combination of thermal and mechanical properties—thermal conductivity, thermal expansion coefficient, Young's modulus, and toughness—improve the thermal shock resistance of the alumina ...
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To substitute bauxite-SiC refractories which are currently used in transition zone of cement kilns, this paper aims to fabricate novel working lining with lower thermal conductivity and outstanding abrasion resistance. For this purpose, a composite refractory material, based on the incorporation of zircon and fused zirconia-mullite (FZM) into …
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These voids and micro-cracks were then filled with air, whose thermal conductivity of 0.0267 W·m −1 ·K −1 is much lower than that of the solid phase. This hindered phonon propagation inside the material, resulting in a 10 % decrease in the thermal conductivity (2.04 W·m −1 ·K −1) of the MC sample after 20 thermal cycles.
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Aluminum oxide is an electrical insulator but has a relatively high thermal conductivity ((30, W m^{-1} K^{-1})) for a ceramic material. It is thus used as insulating material in power electronics. Aluminum oxide is responsible for resistance of metallic aluminum to weathering. ... Bauxite is purified by the Bayer process which is the ...
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At high temperatures of 200–800 °C, the thermal conductivity of more than 60% of the modified pearlescent sand–bauxite castable was smaller than that of conventional bauxite castable.
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At high temperatures of 200–800 °C, the thermal conductivity of more than 60% of the modified pearlescent sand–bauxite castable was smaller than that of conventional bauxite castable.
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DOI: 10.1016/J.CERAMINT.2018.07.132 Corpus ID: 139987474; Abrasion resistance and thermal conductivity of ZrO2-containing bauxite refractories in the transition zone of a cement kiln
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When the addition of low-grade raw bauxite was 34.5%, the compressive strength of the refractories treated at 1600°C was up to 104.3 MPa, and its thermal conductivity tested at 1000°C was only 1.02 W/(m K).
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The thermal conductivity of type B TBAB CHS is around 0.38–0.45 W m −1 K −1 at the solid fraction of 10.0–40.0 wt% in the present experiments, and the thermal conductivity of TBAB aqueous solution is slightly smaller than that of TBAB CHS and it increases with the decrease of the mass concentration of TBAB aqueous solution.
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There is a long process to transform bauxite, a critical raw material, into a substance with the required properties of cast aluminum alloys for use in electro automotive parts. ... Thanks to its unique properties (low density, high thermal conductivity, non-toxicity, excellent corrosion resistance, as well as easy casting, machining and ...
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Thermal conductivity was increased with bauxite additives increases, because the porosity decreases due to glass phase increasing from fluxing oxides, which melt at …
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Alumina is an electrically insulating material but possesses a relatively high thermal conductivity, a combination that is rare among most ceramics. Production of Alumina. The production of Alumina primarily involves the Bayer process, where bauxite ore is digested in a hot solution of sodium hydroxide.
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Thermal behavior of three characteristic samples from the lower bauxite horizon from locality of Atalandi, Locrida area (Greece) was investigated in the temperature range 20–1250°C by means of emanation thermal analysis (ETA) as well as simultaneous DTA and TG/DTG. The major elements of the samples and the chemical composition of …
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Fig. 11 shows the results of thermal conductivity, revealing the expected increase of thermal insulation when the content of lightweight aggregates increases. Specifically, when the volume fraction of perlite, vermiculite, and spheres is increased by 10% in the composite, a reduction of 56%, 47%, and 25% of thermal conductivity …
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At 600–1000°C, the thermal conductivity of the modified pearlescent sand castable is about 30% lower than that of the conventional castable, which proves that the addition of modified pearlescent sand …
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