METHOD OF PRODUCTION OF THE GYPSUM BINDING AGENT Russian patent published in 2007 - IPC C04B11/02 

FIELD: construction materials industry; ceramics industry; porcelain-faience industry; other industries, methods of production of the gypsum binding agents.

SUBSTANCE: the invention is pertaining to the field of the construction materials industry and may be used for manufacture of the molds in the ceramic, porcelain-faience and other industries. The method of production of the gypsum binding agent includes of the gypsum rock, separation of the produced gypsum crushed rock into fractions, the hydrothermal treatment of the fraction of the gypsum crushed rock with the subsequent thermal treatment and the grinding, The separation of the gypsum crushed rock they make for the fraction of 0-20 mm and the fraction of 20-40 mm, then the gypsum crushed rock of the fraction of 20-40 mm is subjected within 5-6 hours to the hydrothermal treatment in the interval of the temperatures of 120-150°С and under the air pressure of 1.1-1.5 atm. After that the gypsum crushed rock of the fraction of 20-40 mm is mixed with the crude gypsum crushed rock of the fraction of 0-20 mm in the ratio accordingly (1-3 : 1)in shares of the mass. Then the produced mixture is subjected to the thermal treatment at the temperature of 120-150°С in the rotating furnace. The technical result of the invention is the increased homogeneity of the gypsum binding agent, reduction of the contents in it of the two-aquatic calcium sulfate, the increased time intervals of hardening and the reduced volumetric expansion.

EFFECT: the invention ensures the increased homogeneity of the gypsum binding agent, the reduced contents in it of the two-aquatic calcium sulfate, the increased time intervals of its hardening and the reduced volumetric expansion.

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