METHOD FOR PRODUCTION OF GYPSUM BINDING AGENT Russian patent published in 2009 - IPC C04B11/02 

FIELD: construction; chemistry.

SUBSTANCE: invention is related to methods for production of gypsum binding agents, including anhydrite, and also dry mixtures for production of construction products and structures, including monolithic wall partitions, ceiling slabs. In method for production of gypsum binding agent by means of processing of raw materials - carbonate or oxide of calcium - with sulfuric acid, dehydration of produced gypsum at normal pressure and temperature of 120-140°C or 400-500°C, or 800-900°C, or in autoclave at the pressure of 1.3 atm, with further crushing of produced product till residue on sieve 02 does not exceed 12%, specified raw materials are previously mixed with magnesium sulfate at the ratio of 500-1000:1 accordingly, specified treatment is realised by mixing with concentrated sulfuric acid at the ratio of 1:1, with spraying of water on reacting mixture, at that water is heated up to temperature of 70-80°C, in amount of 3-5% from mass of reacting mixture, soaking is realised to room temperature, prepared product is neutralised by magnesium oxide, and crushing is done in the presence of complex additive, which contains the following components, wt %: superplasticiser C-3 38-40, waterproofing agent "Sofexil" 48-60, alkali drain from production of caprolactam 0.8-2.0, foam suppressor "Norka" 0.01-0.05, water - the rest, taken in amount of 1 % of neutralised product.

EFFECT: higher strength and water resistance.

4 ex, 1 tbl