Gypsum and lime dry mixes

The main feature of dry gypsum-lime mixtures is that they can be prepared not by simply mixing construction gypsum and lime-fluff, but by firing two-water gypsum due to the heat of quenching ground quicklime.

Gypsum-lime dry mix according to this method is made as follows. Gypsum stone and lump lime are crushed in a jaw or hammer crusher to pieces of 5-10 mm in size, and then ground in a ball mill at the same time or mixed after separate grinding in a mixer in the ratio gypsum : lime = 1 : 0.6 - 1 : 1 (depending on the quality of the starting materials). Materials are crushed to a residue on the No. 02 sieve of no more than 10%. The resulting mixture is sent to a heat-insulated silo, where the reaction between lime and two-water gypsum is carried out at 140-160°.

Gypsum-lime mixtures when closed with water set in 10-20 minutes. They are used for the manufacture of solutions with a compressive strength of up to 2-3 MPa or more.