Dry powder gypsum mortar and preparation method thereof

Abstract

The invention relates to a dry powder gypsum mortar and a preparation method thereof, wherein the dry powder gypsum mortar comprises the following components by weight percent: 25%-40% of calcined desulfurization gypsum, desulfurization gypsum less than 10%, 3.0%-8.0% of cement, 5.0%-25% of coal ash, 1.0%-5.0% of lignocellulose, 0.5%-2.0% of inorganic gel, 0.2%-0.5% of a water retention agent, 0.1%-0.2% of a water-reducing agent, a retarding agent less than 0.5%, 0.1%-1.0% of inorganic salt, sodium hydroxide less than 1.0% and 45%-65% of dried building sand with the fineness being 2.5-0.15mm.

Description

technical field [0001] The present invention relates to a dry powder gypsum mortar for construction and its preparation method, in particular to a dry powder gypsum prepared together with fly ash by using calcined desulfurized gypsum from power plant waste slag and using desulfurized gypsum instead of natural gypsum . Background technique [0002] When the gypsum mortar prepared by traditional natural gypsum is used in building construction, due to the uneven internal stress of the gypsum mortar used for construction, it does not have good compressive and flexural properties. The construction thickness is limited. If the plaster thickness exceeds 10mm, it should be constructed in layers, and the thickness of each layer should be controlled within 10mm. Especially when the aerated concrete block is plastered, it is more likely to cause the plaster layer to be hollow, cracked, and the ash layer to fall to the ground. [0003] In view of this, the Chinese invention patent app...

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Problems solved by technology

[0007] The dry powder gypsum mortar disclosed by the present invention adopts a small amount of desulfurized gypsum (<10%) on the basis of using calcined desulfurized gypsum, which is an environmentally friendly and waste residue utilization component, to ensure a lower cost than the existing technology. Maximize the use of power plant waste residue, and effectively adjust the phosphorus output time of the gypsum mixture cement when in use, thereby adjusting the setting time of the gypsum mixture cement; at the same time, after using a small amount of desulfurized gypsum to adjust the setting time of the gypsum mixture cement, The use ratio of traditional retarders has also decreased, which solves the problem of rising product costs of the overall gypsum mixture due to the use of expensive retarders. Among them, under the condition of ensuring the flexural and compressive strength, the use of desulfurized gypsum <10% The ratio of the product can be adjusted within 30-180 minutes to meet the requirements of different construction techniques