Nepheline syenite powder with controlled particle size and novel method of making same
AssigneeUnimin Corporation
InventorsScott VanRemortel, Robert Ratcliff, Ibezim Anazia, Louis M. Schlesinger
Life of this patent
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Abstract
An ultra-fine nepheline syenite powder produced from a pre-processed nepheline syenite powder feedstock. The powder having a “controlled” maximum grain size D95 or D99 of less than about 20 microns and a “controlled” minimum grain size D5 in the range of 2-8 microns with a particle size spread D5-D95 of less than about 12 microns.
Claims45
An ultra-fine nepheline syenite powder produced from a feedstock constituting pre-processed nepheline syenite powder with a maximum grain size D99 in the range of 20-100 microns, said ultra-fine nepheline syenite powder produced from said feedstock has a moisture content of less than 0.8% by weight, a narrow particle size distribution of D5 to D99 of less than about 12 microns, a D50 grain size which is 35-55% of the D99 grain size and a controlled minimum grain size at a target value greater than about 2 microns.
A method of producing an ultra-fine nepheline syenite powder, said method comprising:
- (a) providing a pre-processed commercial nepheline syenite powder as a feedstock with a controlled maximum grain size D99 in the range of about 20-100 microns;
- (b) milling said feedstock to reduce the maximum grain size D95 to a controlled value of about 7-15 microns.
- (c) passing said milled feedstock through an air classifier to remove particles of less than a minimum grain size D5, said minimum grain size being in the range of about 2-8 microns.
A method of producing an ultra-fine nepheline syenite powder, said method comprising:
- (a) providing a pre-processed commercial nepheline syenite powder as a feedstock with a controlled maximum grain size D99 in the range of about 20-100 microns;
- and,
- (b) removing particles with a small grain size of less than a value in the ranges of about 2-8 microns.
A method of producing an ultra-fine nepheline syenite powder, comprising:
- (a) providing a commercial grade nepheline syenite feedstock with a controlled maximum grain size of less than about 20-100 microns;
- (b) grinding said feedstock in a fluidized bed opposed jet mill;
- (c) classifying said ground feedstock in said mill with a classifier to pass an intermediate powder from said mill, said intermediate powder having only particles of nepheline syenite with particle sizes less than a given first value of less than 20 microns;
- and,
- (d) classifying said intermediate powder through an air classifier to remove particles having a grain size less than a given second value.
A method of producing an ultra-fine nepheline syenite powder from a preprocessed nepheline syenite feedstock with a controlled maximum grain size of less than about 20-100 microns, said method comprising:
- (a) passing said feedstock through a first air classifier to remove particles having a size greater than a given first value less than 20 microns;
- and,
- (b) passing said feedstock through a second air classifier to remove particles less than a second given value in the range of 2-8 microns.
A coating including an ultra-fine nepheline syenite powder with a controlled maximum grain size D99 in the range of about 10-20 microns and a controlled minimum grain size D5 in the range of about 2-8 microns.
An ultra-fine powder formed of a given syenitic material produced from a feedstock constituting pre-processed commercial grade powder formed from said given material with a maximum grain size D99 of less than 100 microns, said ultra-fine powder produced from said feedstock has moisture content of less than 0.8% by weight, a narrow particle size distribution of less than 12 microns, a controlled minimum grain size D5 at a target value greater than 2 microns and a controlled maximum grain size D95 in the range of about 15-20 microns.
A method of producing an ultra-fine nepheline syenite powder, said method comprising:
- (a) providing a pre-processed nepheline syenite powder feedstock having a controlled maximum grain size D99 in the range of about 15-20 microns;
- and,
- (b) passing said feedstock through an air classifier to remove particles having a size less than a value in the range of about 2-8 microns.
An ultra-fine nepheline syenite powder produced from a feedstock constituting pre-processed nepheline syenite powder with a maximum grain size D99 in the range of 20-100 microns, said ultra-fine nepheline syenite powder produced from said feedstock has a moisture content of less than 0.8% by weight, a narrow particle size distribution of D5 to D99 of less than about 12 microns, a controlled minimum grain size D5 in the range of about 4-6 microns and a controlled maximum grain size D99 of about 15 microns.
An ultra-fine nepheline syenite powder with a controlled minimum particle size D5 of 2-8 microns to provide a narrow particle size range of less than about 12 microns.
Dependencies are inferred from the claim text.