Synergistic use of electrolytic manganese residue and barium slag to prepare belite- sulphoaluminate cement study

Characterisation and hydration of ye'elimite containing cements

The manufacture of cement is associated with a large amount of CO2 emissions. Mineral carbonation technology (MCT) has been identified as one of the viable solutions to reduce the high environmental impacts of cement and concrete production via a long-term storage of atmospheric CO2 as stable forms of carbonates in cement-based products. This article reviews the status quo of hydration and carbonation activities of all calcium silicates system, especially three main non-hydraulic calcium-silicate-based binders (e.g. γ-C2S, C3S2 and CS). The influence of mineral structure on the types of carbonation products is examined to fundamentally explain the evolution of carbonation products and provide a solid theoretical basis for a wider application of carbonation technology in the future. Finally, effective measures to improve the carbonation performance are comprehensively discussed from the aspects of CO2 concentration, relative humidity, carbonation temperature, W/C ratio, etc., to highlight the potential of non-hydraulic calcium-silicate-based binders in reducing the global cement-associated CO2 emissions. 

Review on CO2 curing of non-hydraulic calcium silicates cements: Mechanism, carbonation and performance

Cation substitution induced reactivity variation on the tricalcium silicate polymorphs determined from first-principles calculations

The present invention relates to a method for the production calcium sulfoaluminate (belite, ferrite, ternesite) clinker using fluxes/mineralizers comprising the following steps - providing a raw meal comprising at least sources of CaO, AI 2 O 3 , SO 3 - sintering the raw meal in a kiln at 1100 to 1350 °C to provide a clinker, - cooling the clinker, wherein at least one compound containing copper and a glass powder or a glass powder are added prior to sintering. The invention further relates to the clinker obtained, as well as to calcium sulfoaluminate based cements and binders produced from the clinker.

Fluxes/Mineralizers for calcium sulfoaluminate cements

Formation and coexistence of tricalcium silicate (C3S) and calcium sulphoaluminate (C4A3
 $$
\bar S
$$
 ) minerals in Portland cement clinker containing calcium sulphoaluminate were investigated. The f-CaO content, mineral composite and formation of mineral in the clinker were analyzed respectively by chemical analysis, differential scanning calorimetry(DSC) and X-ray diffraction. The results show that, adding a suitable amount of BaO can improve the burnability of raw meal and promote the f-CaO absorption. Tricalcium silicate and calcium sulphoaluminate minerals can form and coexist in clinkers at 1 234–1 317 °C by the addition of BaO to the raw meal. A suitable amount of BaO expanded the coexistence temperature of two minerals by 58 °.

Effect of barium oxide on the formation and coexistence of tricalcium silicate and calcium sulphoaluminate

Calcium sulphoaluminate was prepared with chemical reagents in this paper. The formation mechanism of calcium sulphoaluminate and effect of CuO on the formation mechanism of calcium sulphoaluminate were investigated by the chemical analysis, X-ray diffraction (XRD), and differential scanning calorimetry (DSC). The results show that there are three ways in the formation of calcium sulphoaluminate. CuO can promote the decomposition of calcium carbonate and decrease the formation temperature of calcium sulphoaluminate
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. When the burning temperature is below 1 000 °C, the addition of CuO can promote the formation of calcium sulphoaluminate, while CuO can not favor the formation of calcium sulphoaluminate above 1 000 °C.

Effect of CuO on the Formation Mechanism of Calcium Sulphoaluminate

Fabrication of alginate-based microspheres with cellular structure for tuning ammonium dinitramide performance

Optimization of the content of tricalcium silicate (C3S) of high cementing clinker was investigated. The content of free-CaO(f-CaO), mineral composite, the content of C3S in the clinker and the hydration product were analyzed by chemical analysis and X-ray diffraction (XRD). “K Value” method of QXRD was selected as a quantitative analysis way to measure the content of C3S, and the strength of cement paste was determined. The results show that at a water cement ratio of 0.29, the strength of cement paste with 73% C3S can be up to 97.5 MPa at 28 days age. The strength at 28 d of cement with 73% C3S is 16% higher than that with 78% C3S at water requirement for normal consistency. The relationship between the strength of high cementing Portland cement and the content of C3S in the clinker is nonlinear. According to the strength of cement paste, the optimal content of C3S in cement clinker is around 73% in this paper.

Yeping Huang

Papers

Effect of barium oxide on the formation and coexistence of tricalcium silicate and calcium sulphoaluminate

Effect of CuO on the Formation Mechanism of Calcium Sulphoaluminate

Fabrication of alginate-based microspheres with cellular structure for tuning ammonium dinitramide performance

Optimization of the content of tricalcium silicate of high cementing clinker