Preparation method of composite single-component alkali-activated cement cured at room temperature

Abstract

The invention discloses a preparation method of composite single-component alkali-activated cement cured at room temperature. Raw meal powder is prepared from raw material containing a silicon-aluminum oxide, dolomite sodium carbonate and the like through mixing and ball-milling, wherein the charge ratio meets the conditions that the molar ratio of (CaO+MgO) / SiO2 is 1.0-2.1 and the molar ratio of (Na2O+K2O) / SiO2 is 0.3-0.7; the raw meal powder is calcined at 1100 DEG C for 2-3 hours, thus obtaining a clinker; and 10-30 parts of slag, 5-15 parts of slaked lime and 10-60 parts of gypsum are added to 100 parts of the clinker and the mixture is evenly mixed and ground, thus obtaining the cement. The cement prepared by the method has high early-high-strength, and especially has good long-term strength which is obviously superior to that of the prior art; the cement does not crack after being cured for a long period of time; the problem that the existing cement is easy to crack or break at the later period is solved; the raw materials are available; particularly, the proportions of cheap raw materials are high; the production cost is effectively reduced; and the composite single-component alkali-activated cement is simple in preparation method and convenient to use and maintain, and has good application value.

Description

technical field [0001] The invention belongs to the field of new cement materials, and in particular relates to a preparation method of normal-temperature curing composite single-component alkali-activated cement. Background technique [0002] my country is the country with the highest cement production in the world. In 2013, the cement production reached 2.43 billion tons, most of which were Portland cement. The calcination temperature of Portland cement reaches 1450°C, high energy and material consumption, high carbon emissions, serious environmental pollution, poor acid resistance, corrosion resistance and durability, and consumes a large amount of high-quality limestone resources, so its use should be gradually restricted and reduced. The alkali-activated cement that has been studied more recently is a two-component cement composed of an aqueous solution of a strong alkali salt and an active solid oxide powder, in which the typical component is Na 2 O-Ca(Mg)O-Al 2 o 3...

AI Technical Summary

Problems solved by technology

However, alkali slag is mainly made of iron-making by-products, and its composition and performance are unstable. Moreover, industrial alkali and water glass are used as activators to make its cost too high and it is difficult to compete with Portland cement.

[0003] In order to improve the cost performance of alkali-activated cement, patents ZL201110405630.3 and ZL201110405626.7 propose the method of directly calcining clay with alkali to prepare single-component geopolymer cement, and patent ZL201210238413.4 uses the method of calcining clay with alkali and calcium magnesium carbonate method to prepare single-component alkali-activated cement to reduce the production cost, and patent ZL201210410858.6 further invented a low-temperature calcination to prepare single-component alkali-activated cement for room temperature curing, but the latter still has low room temperature curing strength and is prone to cracking and damage in the later stage Defects

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