Preparation method of anhydrous phosphogypsum-based assembled lightweight partition wall slats

Abstract

The invention discloses a preparation method of an anhydrous ardealite-based assembly-type light partition wall batten. According to the technical scheme, anhydrous ardealite, semi-hydrated ardealite,gypsum whiskers, an air entraining agent and a water-retaining agent are mixed, stirred and uniformly dispersed, then according to the water cement weight ratio of 0.5-0.6, water is added, nano-calcium sulfate and a water reducing agent are added, after uniform stirring, lightweight aggregate is slowly added to the mixture, stirring is conducted until uniform dispersion is achieved, and slurry isobtained; finally, the obtained slurry is quickly injected in a mold for forming, and the anhydrous ardealite-based assembly-type light partition wall batten is obtained. The technology is simple, the production cost is low, and the prepared product is high in waste utilization rate, high in early strength, unobvious in layering and cracking, light, capable of preserving heat and adjustable in volume weight.

Description

technical field [0001] The invention relates to the technical field of building materials, in particular to a preparation method of anhydrous phosphogypsum-based assembled lightweight partition wall slats. Background technique [0002] Phosphogypsum is an industrial by-product of wet process production of phosphoric acid, and its main component is calcium sulfate dihydrate, with a content of about 90%. Due to the influence of the preparation process, phosphogypsum is strongly acidic (pH<3), and contains phosphorus, fluorine, organic matter and some radioactive elements. The existence of impurities and radioactive elements in phosphogypsum, as well as the unstable properties caused by different phosphate rocks, restrict the comprehensive utilization of phosphogypsum. As a result, phosphogypsum is mainly disposed of in open-air storage, which not only takes up a lot of land and wastes resources, And harmful impurities are leached out with rainwater, producing acidic wastew...

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Problems solved by technology

Chinese patent CN106565181A discloses a preparation method of lightweight concrete prefabricated slabs, which can realize demoulding within 6 to 8 hours, and has the characteristics of high finished product strength and light surface density. Defects include chemical shrinkage, drying shrinkage and carbonization shrinkage, etc., which cannot overcome the shortcomings of sheet shrinkage and cracking

[0004] Chinese patent CN105777039B discloses a phosphogypsum-based lightweight insulation board and its preparation method, which can achieve a dry density of 460-670Kg / m 3 , the thermal conductivity is 0.08-0.2W / (m·K), but its main cementitious materials are phosphorus building gypsum and phosphorus high-strength gypsum. Due to the high impurity content, there are problems of unstable performance. At the same time, the low body strength and poor water resistance also restrict its experiment

The calcination temperature of anhydrous phosphogypsum is 500-700℃, the impurity content is less, and the performance is more stable than hemihydrate phosphogypsum. The prepared product has the advantages of high waste rate and high early strength. The introduction of anhydrous phosphogypsum can better solve the problem. The above technical problems, but after the introduction of anhydrous phosphogypsum, there will be problems such as poor activity, difficulty in excitation, low hydration rate, and low strength of hardened body

At present, researchers mostly use inorganic salt excitation (such as K 2 SO 4 ,FeSO 4 etc.) to improve the hydration rate of anhydrous gypsum to solve the above problems, but it also brings the problem that the product is prone to frosting, and the excitation process mainly occurs in the dissolution stage of anhydrite, and the excitation effect is still poor

Therefore, although people hope to introduce anhydrous phosphogypsum in the field of building materials at present, there is no better way to solve the above technical problems

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