High-temperature calcination production method of industrial byproduct gypsum

Abstract

The invention discloses a high-temperature calcination method of industrial byproduct gypsum, and belongs to the field of building materials. The method includes the following steps: 1. heating the industrial byproduct gypsum by flame; 2. heat preservation; 3. humidification reduction. The method has the advantages of optimizing the calcining process of the industrial byproduct gypsum to obtain the building gypsum with good strength and comprehensive performance, and overcoming the defects of the gypsum produced by the existing method.

Description

technical field [0001] The invention belongs to the field of building materials, in particular to a method for producing building gypsum by using industrial by-product gypsum, especially phosphogypsum. Background technique [0002] Gypsum is a high-quality building material, which is welcomed by the construction industry because of its characteristics of fast solidification, micro-expansion, light weight, water resistance, and fire resistance; most of the gypsum acquisition methods are natural gypsum mines or by-products of industrial production Among them, industrial by-product gypsum includes desulfurization gypsum, phosphogypsum, titanium gypsum, fluorine gypsum, citrate gypsum, etc.; the chemical composition is mainly calcium sulfate dihydrate; currently, the treatment of industrial by-product gypsum mainly uses hot air contact or heat The oil conversion device is in contact with the industrial by-product gypsum, and the industrial by-product gypsum is indirectly heated ...

AI Technical Summary

Problems solved by technology

[0002] Gypsum is a high-quality building material, which is welcomed by the construction industry because of its characteristics of fast solidification, micro-expansion, light weight, water resistance, and fire resistance; most of the gypsum acquisition methods are natural gypsum mines or by-products of industrial production Among them, industrial by-product gypsum includes desulfurization gypsum, phosphogypsum, titanium gypsum, fluorine gypsum, citrate gypsum, etc.; the chemical composition is mainly calcium sulfate dihydrate; currently, the treatment of industrial by-product gypsum mainly uses hot air contact or heat The oil conversion device is in contact with the industrial by-product gypsum, and the industrial by-product gypsum is indirectly heated to 130°C-170°C by hot air or hot oil conversion device, so that the crystal water in the industrial by-product gypsum is partially dehydrated to produce hemihydrate gypsum The main component is a mixture of a small amount of anhydrous type III gypsum and dihydrate gypsum, also known as building gypsum; this method has the following defects. First, because building gypsum is produced continuously, the temperature range of 130°C-170°C is too small , uneven mechanical stir-frying and uneven fineness of dihydrate gypsum raw materials will lead to the inability to accurately control the ratio of dihydrate gypsum to anhydrous type III gypsum, and the quality of the produced building gypsum cannot be stable, so that downstream building material manufacturers are in gypsum The addition of various additives in the production process of building materials can not be stable, which brings great difficulties to the production of downstream building materials, and industrial by-product gypsum, especially phosphogypsum, often contains phosphate ions, fluoride ions, eutectic phosphorus and Biological impurities, which are difficult to remove when calcined below 200°C, will cause harm to the quality and quality of building gypsum