Prodn. of mining mortar based on natural anhydrite - by mixing anhydrite with water to form slurry, pumping through pressure stable pipe, adding auxiliary, and discharging mixt.

摘要

In the prodn. of a mining mortar based on natural anhydrite and an auxiliary (a) the anhydrite is present in an amt. of at least 30 (pref. 40-60)wt.%, has a grain size of less than 0.2mm; and (b) the residual has a max grain size of 6mm. (c) anhydrite is mixed with water to form a pumpable slurry with a spreading extend of approx. 20cm on the jolt table according to DIN 1168 (part 2); (d) slurry is pumped through a pressure stable pipe of 80mm dia.; (e) auxiliary is added close to the end of the pipe and mixed with the slurry; and (f) mixt. is discharged normally. Fluxing agent and/or binding delaying agent is pref. mixed with the pumpable slurry in step (c). Thickener is added in step (e). Mixing in step (e) is carried out in a static mixer. Auxiliary and opt. thickener are added in the form of a suspension or dry form. ADVANTAGE - Dust formation is prevented.