10 results about "Alite" patented technology

To provide a powdery cement composition including a high content of fine limestone powder, i.e., a powdery cement composition capable of exhibiting high compression strength when used as a material for concrete or the like and excellent sulfate resistance.SOLUTION: There is provided a powdery cement composition comprising cement and fine limestone powder, i.e., a powdery cement composition whose mineral composition according to the Bogue's formula satisfying the following conditions: an alite content being 50 to 70 mass%, a belite content being 5 to 15 mass%, an aluminate phase content being 2 to 10 mass%, a total content of alite and belite being 60 to 80 mass%, and the mass ratio of alite relative to belite (alite / belite) being 5 to 10, and a fine limestone powder content in the powdery cement composition being 5 to 15 mass%.SELECTED DRAWING: None

Provided is a powdery cement composition containing a fine limestone powder in a large proportion, the powdery cement composition, when used as a material for concrete or the like, being capable of giving high compression strength and having excellent sulfate resistance.　The powdery cement composition comprises a cement and a fine limestone powder. The mineralogical composition of the powdery cement composition calculated by the Bogue formula satisfies the conditions of: an alite content of 50-70 mass%; a belite content of 5-15 mass%; an aluminate phase content of 2-10 mass%; a total content of alite and belite of 60-80 mass%; and a mass ratio between alite and belite, alite / belite, of 5-10. The proportion of the fine limestone powder in the powdery cement composition is 5-15 mass%.

The invention discloses a method for calculating the reaction degree of each component in an ordinary Portland cement-slag system, and belongs to the field of concrete materials.The method comprises the steps that ordinary Portland cement-slag mixed slurry is prepared; obtaining a characteristic element distribution diagram by utilizing electronic probe micro-area analysis; the method comprises the following steps: sequentially performing image recognition and segmentation on unreacted fly ash particles, unhydrated tetracalcium aluminoferrite clinker, unhydrated alite and belite clinker (through calcium-rich phase screening and theoretical silicon-calcium ratio judgment) and unreacted slag particles on the basis of element characteristics of each phase of an ordinary Portland cement-slag system; by calculating the volume fraction of the unreacted particles and combining the initial mix proportion and the material density of the system, the reaction degrees of the components such as the cement and the slag are finally and accurately quantified. According to the invention, accurate quantification of the reaction degree of each component in the ordinary Portland cement-slag system is realized.

The invention provides a method for preparing alite sulphoaluminate clinker by using red mud. The method comprises the following steps: pretreating bauxite and red mud to obtain a premix; then proportioning the limestone, the premix and the desulfurized gypsum according to a formula; grinding the prepared raw materials in a mill to obtain a raw material; and uniformly mixing the prepared raw material with a composite catalyst, putting the mixture into a kiln, calcining at 1300-1350 DEG C, and cooling the calcined product to obtain the alite sulphoaluminate clinker. By adding the composite catalyst into the raw material, the firing temperature of tricalcium silicate is reduced to be within the firing temperature range of calcium sulphoaluminate, decomposition of calcium sulphoaluminate in the firing process of tricalcium silicate is avoided, the content of tricalcium silicate is increased while the content of calcium sulphoaluminate is not reduced, and the production cost is reduced. The early strength performance of the Alit sulphoaluminate cement, which is lost after the red mud is added, is supplemented. In addition, before the raw material is prepared, the red mud is subjected to dealkalization treatment, so that the influence of alkali on the performance and the later strength of the cement clinker is reduced.

Provided is a powdery cement composition which contains a crushed clinker, gypsum, and limestone fine powder, in which the proportion of an aluminate phase in the crushed clinker is not less than 5 mass%, and which has excellent sulfate resistance even with a large proportion of the limestone fine powder.　A composition according to the present invention comprises a crushed clinker, gypsum, and limestone fine powder, wherein the crushed clinker contains 58-68 mass% of alite, 12-19 mass% of belite, 5-10 mass% of an aluminate phase, and 7-13 mass% of a ferrite phase in terms of calculated values according to the Bogue formula, the proportion of SO3 in the composition is 2.2-3.2 mass%, the proportion of powder having a grain size of not more than 10 μm is not less than 65 mass% in the limestone fine powder, the amount of the limestone fine powder is 5-11 parts by mass relative to the total of 100 parts by mass of the crushed clinker and the gypsum, and the Blaine specific surface area of the composition is 3,700-5,000 cm2 / g.

To provide a powdered cement composition which contains ground clinker, gypsum, and limestone fine powder, and in which the proportion of an aluminate phase in the ground clinker is 5 mass% or more, and which has excellent sulfate resistance despite the high proportion of limestone fine powder.SOLUTION: There is provided a powdery cement composition which contains a crushed clinker, gypsum, and limestone fine powder, in which the crushed clinker contains 58 to 68 mass% of alite, 12 to 19 mass% of belite, 5 to 10 mass% of an aluminate phase, and 7 to 13 mass% of a ferrite phase in terms of calculated values according to the Bogue formula, the proportion of SO3 in the composition is 2.2 to 3.2 mass%, the proportion of powder having a grain size of 10 μm or less is 65 mass% or more in the limestone fine powder, the amount of the limestone fine powder is 5 to 11 pts.mass relative to the total of 100 pts.mass of the crushed clinker and the gypsum, and the Blaine specific surface area of the composition is 3,700 to 5,000 cm2 / g.SELECTED DRAWING: None

The invention discloses ultra-high performance concrete based on alite-belite-calcium sulphoaluminate cement and a preparation method of the ultra-high performance concrete. The ultra-high performance concrete is prepared from 550-800 parts of alite-belite-calcium sulphoaluminate cement; 100 to 300 parts of an active mineral admixture; 100 to 200 parts of silica fume; 30 to 70 parts of silicon dioxide powder; 900 to 1300 parts of quartz sand; 120 to 250 parts of steel fiber; 15 to 35 parts of a water reducing agent; 130-180 parts of water; and 0-30 parts of an optional component activated aluminum oxide micro powder. According to the invention, the micro-expansion characteristic of calcium sulphoaluminate (CSA) in the ABY cement is fully utilized to effectively compensate shrinkage cracking, the quick-setting characteristic of the cement is well matched with the retarding effect of the polycarboxylic acid water reducer, the mineral admixture plays a synergistic effect of filling and activity, the dependence on high-temperature maintenance is obviously reduced by the high hydration activity of ABY, and the high-temperature curing performance of the cement is greatly improved. The UHPC with excellent volume stability, high early and later strength and good constructability is obtained.

The invention discloses a belite-alite-calcium sulphoaluminate-iron phase system low-calcium high-gelling clinker and a preparation method thereof, and belongs to the technical field of cement materials. The method comprises the following steps: by taking a calcium source, a silicon source, an aluminum correction raw material, an iron correction raw material and gypsum as raw materials, grinding, homogenizing and mixing to prepare a raw material; calcining the raw material at low temperature, then rapidly cooling, and grinding to obtain clinker; the clinker is prepared from the following mineral components in percentage by weight: 35.0 to 55.0 percent of C2S, 7.0 to 35.0 percent of C3S, 10.0 to 20.0 percent of C4A3 and 13.0 to 18.0 percent of C4AF. The key point of the method is that the content of each mineral phase reaches a design value by optimizing process parameters. The 3-day compressive strength and 28-day compressive strength of cement mortar prepared from the clinker prepared by the invention can respectively reach 35.0 MPa or above and 55.0 MPa or above; and the CaO content in the clinker is lower than 60% and is obviously lower than the CaO content in ordinary Portland cement clinker, so that the carbon emission in the cement production process is effectively reduced.

This invention discloses a highly corrosion-resistant Belite sulfoaluminate cement clinker, its preparation method, and its applications. The mineral composition of the cement clinker, by mass percentage, includes: C3S 6%–15%, C2S 42%–54%, C4A3 20%–30%, and C4AF 15%–22%. The highly corrosion-resistant Belite sulfoaluminate cement clinker of this invention introduces an appropriate amount of C3S into its phase composition and increases the content of C4AF, forming a four-phase cement clinker dominated by Belite and Yelimite, supplemented by Alite and iron phases. This clinker is used for coordinated strength development at various ages in cement, exhibits good 28-day bond strength, and also possesses excellent resistance to seawater erosion.

The present invention discloses a chemical admixture for synchronously promoting cement mineral hydration and a preparation method thereof. The chemical admixture for synchronously promoting cement mineral hydration described by Amin includes three mineral phase hydration promoting components, namely alite, belite and iron phase, and a balancing agent, wherein the hydration promoting components of each mineral phase are balanced by the balancing agent. The present invention adopts a multi-component composite modification method, selects hydration stimulating substances for three mineral phases, synchronously promotes the hydration process of each mineral phase in cement, and selects reasonable solvents and balancing agents to balance the compatibility of multiple compound components, and finally realizes the improvement of the hydration degree of cement-based materials, generates more hydration products per unit time, compacts the accumulation of hydration products and improves the strength, and realizes the regulation of the microstructure of cement-based materials and the effective improvement of durability.