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Bags of portland cement wrapped and stacked on a pallet. Blue Circle Southern Cement works near Berrima, New South Wales, Australia.. Portland cement is the most common type of cement in general use around the world as a basic ingredient of concrete, mortar, stucco, and non-specialty grout.
West African Portland Cement company began operations in 1961 at Ewekoro, the firm was formally established in 1959 as a joint venture between Blue Circle, United Africa Company of Nigeria and the Western regional government in Nigeria. Blue Circle, previously known as Associated Portland Cement Manufacturers was Nigeria's largest supplier of ...
Calcium silicate hydrate (also shown as C-S-H) is a result of the reaction between the silicate phases of Portland cement and water. This reaction typically is expressed as: 2 Ca 3 SiO 5 + 7 H 2 O → 3 CaO · 2 SiO 2 · 4 H 2 O + 3 Ca(OH) 2 + 173.6 kJ. also written in cement chemist notation, (CCN) as: 2 C 3 S + 7 H → C 3 S 2 H 4 + 3 CH + heat
Portland cement clinker (abbreviated k in the European norms) is ground to a fine powder and used as the binder in many cement products. A small amount of gypsum (less than 5 wt.%) must be added to avoid the flash setting of the tricalcium aluminate (Ca 3 Al 2 O 6 ), the most reactive mineral phase (exothermic hydration reaction) in Portland ...
Cement kilns are used for the pyroprocessing stage of manufacture of portland and other types of hydraulic cement, in which calcium carbonate reacts with silica-bearing minerals to form a mixture of calcium silicates. Over a billion tonnes of cement are made per year, and cement kilns are the heart of this production process: their capacity ...
Tricalcium aluminate hydrates in the process of forming Portland cement. Using X-ray diffraction , two hydrates form, the hexahydrate abbreviated C3AH6 and a nonadecahydrate abbreviated C4AH19. In the presence of gypsum , a component of typical clinkers, the sulfate (S) forms with the formula C4ASH12.
Calcium aluminates can form complex salts in combination with different types of anions.Two series of calcium aluminates are known in cement chemistry: AFm and AFt phases, being respectively mono- or tri-substituted with a given divalent anion X (e.g. SO 2− 4, CO 2− 3, or hosting a divalent impurity such as SeO 2− 4 [3]...), or with two units of a monovalent anion, e.g. OH −, Cl − ...
An AFm phase is an "alumina, ferric oxide, monosubstituted" phase, or aluminate ferrite monosubstituted, or Al 2 O 3, Fe 2 O 3 mono, in cement chemist notation (CCN). AFm phases are important hydration products in the hydration of Portland cements and hydraulic cements.