B21B27/027

Grinding stabilizing additive for vertical roller mills

A method for grinding a solid in a vertical roller mill (VRM), comprising grinding at least one solid in the presence of a grinding stabilizing additive, wherein the grinding stabilizing additive comprises an alkanol amino acid compound or a disodium or dipotassium salt thereof having the structural formula (I): The definitions of variables R.sup.1, R.sup.2, and R.sup.3 are provided herein. ##STR00001##

EARLY STRENGTH ENHANCEMENT OF CEMENTS

A method of making a cement composition, comprising grinding a cement clinker and a strength-enhancing agent, thereby producing a hydraulic cementitious powder, wherein the strength-enhancing agent is present in the hydraulic cementitious powder in an amount of from 0.001% to 0.09% based on dry weight of the hydraulic cementitious powder. The strength-enhancing agent is a compound represented by the following structural formula (I). The definitions of variables R.sup.1, R.sup.2, and R.sup.3 as well as R.sup.10, R.sup.20, and R.sup.30 are provided herein.

GRINDING STABILIZING ADDITIVE FOR VERTICAL ROLLER MILLS

A method for grinding a solid in a vertical roller mill (VRM), comprising grinding at least one solid in the presence of a grinding stabilizing additive, wherein the grinding stabilizing additive comprises an alkanol amino acid compound or a disodium or dipotassium salt thereof having the structural formula (I): The definitions of variables R.sup.1, R.sup.2, and R.sup.3 are provided herein.

##STR00001##

GRINDING STABILIZING ADDITIVE FOR VERTICAL ROLLER MILLS

Method for grinding a solid in a vertical roller mill (VRM) and a cement composition prepared by the disclosed methods. A method comprises grinding a solid comprising a cement clinker under a water spray in the presence of a grinding stabilizing additive, wherein the grinding stabilizing additive comprises: (i) an alkanol amino acid compound or a disodium or dipotassium salt thereof having the structural formula:

##STR00001##

(ii) a glycol; or a mixture of (i) and (ii), wherein the water spray level is reduced by at least 5% compared to a control. Cement compositions prepared by the disclosed methods have the pre-hydration level (W.sub.k) equal to or less than 1.5%. The values and preferred values of R.sup.1-3 are disclosed herein.