SU65713A1 - The method of obtaining high strength gypsum - Google Patents

Description

Due to its physicochemical and mechanical properties, ordinary construction gpps are used for S construction, mainly as an additive to lime mortars in the production of internal plaster.

Gypsum is avoided to be used for products directly exposed to precipitation as a non-water resistant material.

Meanwhile, it is known, for example, that the pyramids of Khafre and Cheops are plastered from above with gypsum. Gypsum plaster of the pyramids survived until the present, his time.

Gnps is used by itself for the production of pure gypsum products in cases where the product made from it does not have increased requirements in terms of mechanical strength.

From the American patent No. 1901051 of 1933, it is known to obtain high-strength gypsum by treating the gypsum b, ebenka in an autoclave for 6 hours with saturated steam at a temperature of about 123 °.

According to the invention, the steamed gypsum is discharged into the atmosphere of a normal pressure and cooled to a temperature of about 40 °, after which it is dried in a dryer for about two hours at a temperature of about 120 °.

According to the proposed method, the whole process of obtaining high-strength gypsum consists of the following, kx operations:

1) the natural gypsum stone is crushed into pieces of the size ob; about 50 mm (fraction from 10 to 50 mm);

2) this fraction is loaded into vertical or horizontal vessels (steamers);

3) then saturated steam is introduced into the steam chamber at a pressure gauge of 1.3 atmospheres and a temperature of 124 ° C, and this pressure is maintained throughout the whole process, from the moment the steam starts up to its release - b hours; condensate is removed periodically, without reducing the pressure in the steam tank;

4) thereafter, steam is released and the steamed gypsum crushed stone is discharged from the steam plant to the atmosphere of a normal pressure;

however, the temperature of the gypsum macadam can be reduced to 40 ° within about 10-15 minutes;

5) within the next 15 minutes (and only within 30 minutes from the moment of unloading from the boiler) 1pps gravel enters the dryer, where its temperature must be maintained at about 120 ° for 2.5 hours;

6) then dried -.the material enters the grinding powder, 90% of which must pass through a sieve of 900 holes / cm.

Subject invention

The method of obtaining high-strength gypsum by treating gypsum gravel {without preliminary drying) in an autoclave with saturated steam at a temperature of about 124 ° for 5-7 hours, which means that the steamed gypsum is discharged into the environment of a normal atmosphere pressure and cooled to a temperature of about

40 °

then dried in a stalk for about two hours at a temperature of about 120 °.