Basalt fibers produced from high temperature melt

Abstract

Methods, systems and apparatus for producing continuous basalt fibers, microfibers, and microspheres from high temperature melts are disclosed. A cold crucible induction furnace is used to super heat crushed basalt rock to form a melt. The melt is cooled prior to forming a fiber. The fiber produced from the superheated melt possesses superior properties not found with conventional basalt fibers produced in gas furnaces. In some implementations, the superheated melt is spun into continuous basalt fibers. In some implementations, the superheated melt is blown into microfibers and microspheres.

1 .- 88 . (canceled) 
     
     
         89 . A method of producing basalt microspheres, comprising:
 charging a quantity of basalt into an induction furnace, the induction furnace having an interior comprising copper plates and containing substantially no refractory lining;   inductively superheating at least about 100 kilograms of basalt in the induction furnace to form a superheated melt;   cooling the superheated melt by passing the melt through a water cooled tray to form a cooled melt; and   forming the basalt microspheres from the cooled melt, wherein 1 kilogram of microspheres is produced using less than 2.2 kilowatts of electrical power.   
     
     
         90 . The method of  claim 89 , wherein the basalt microspheres have an average diameter from about 0.5 microns to about 215 microns. 
     
     
         91 . The method of  claim 90 , wherein the basalt microspheres have an average diameter from about 0.5 microns to about 3 microns. 
     
     
         92 . The method of  claim 89 , the basalt microspheres are in the shapes of rods or dumbbells. 
     
     
         93 . The method of  claim 89 , the basalt microspheres are solid balls without any entrapped air. 
     
     
         94 . The method of  claim 89 , wherein the induction furnace is a cold crucible induction furnace. 
     
     
         95 . The method of  claim 89 , wherein the superheated melt is substantially homogeneous at a temperature of at least about 2500° C., and the cooled melt is at a temperature below 1500° C. 
     
     
         96 . The method of  claim 89 , wherein forming the basalt microspheres from the cooled melt includes passing the cooled melt through a blowing device. 
     
     
         97 . The method of  claim 96 , wherein the blowing device produces a high speed jet of air and creates an ultrasonic vibration. 
     
     
         98 . The method of  claim 89 , further comprising:
 classifying the basalt microspheres by size.   
     
     
         99 . A method of producing microspheres, comprising:
 charging a quantity of a rock into an induction furnace, the induction furnace having an interior comprising copper plates and containing substantially no refractory lining, the rock comprising plagioclase having a plagioclase melting point and a component having a component melting point, wherein the plagioclase melting point is less than the component melting point;   inductively heating the quantity of the rock in the induction furnace to a furnace temperature above the component melting point to form a superheated melt, cooling the superheated melt to a temperature between the plagioclase melting point and the component melting point by passing the superheated melt though a water cooled tray to form a cooled melt; and   forming microspheres from the cooled melt.   
     
     
         100 . The method of  claim 99 , wherein the rock is basalt. 
     
     
         101 . The method of  claim 100 , wherein the plagioclase melting point is from about 950° C. to about 1200° C. 
     
     
         102 . The method of  claim 101 , wherein the component melting point is from about 1400° C. to about 1600° C. 
     
     
         103 . The method of  claim 102 , wherein the superheated melt is at least about 98% amorphous at the furnace temperature of at least about 2500° C. 
     
     
         104 . The method of  claim 99 , wherein the component is quartz or iron oxide. 
     
     
         105 . The method of  claim 99 , wherein forming microspheres from the cooled melt includes passing the cooled melt through a blowing device. 
     
     
         106 . A method of producing a microspheres, comprising:
 charging a quantity of basalt into a cold crucible induction furnace wherein the induction furnace has an interior comprising copper plates and containing substantially no refractory lining;   inductively heating the quantity of the basalt in the cold crucible induction furnace to a temperature of at least about 2500° C. to form a homogenous melt, wherein the cold crucible induction furnace heats about 1 kilogram of basalt per less than 2.2 kilowatts of electrical power;   cooling the homogenous melt to a temperature less than about 1500° C. by passing the melt through a water cooled tray to form a cooled homogenous melt; and   forming the microspheres by passing the cooled homogenous melt through a blowing device.   
     
     
         107 . The method of  claim 106 , wherein the cold crucible induction furnace heats about 1 kilogram of basalt per less than 2.0 kilowatts of electrical power. 
     
     
         108 . The method of  claim 106 , wherein the cold crucible induction furnace operates at a frequency of about 0.22 megahertz, 0.32 megahertz, 0.44 megahertz, or 1.76 megahertz. 
     
     
         109 . A method of producing microspheres from a homogeneous melt, comprising:
 charging a quantity of basalt rock into a cold crucible induction furnace; inductively heating the quantity of the basalt in the cold crucible induction furnace to a temperature of at least about 2500° C. to form a homogenous melt having a viscosity of less than about 500 cP, wherein the cold crucible induction furnace includes an interior comprising copper plates and containing substantially no refractory lining;   wherein the cold crucible induction furnace heats about 1 kilogram of basalt per less than 2.2 kilowatts of electrical power;   cooling the homogenous melt to a temperature less than about 1500° C. by passing the homogenous melt through a water cooled tray; and   forming the microspheres by passing the cooled homogenous melt through a blowing device.   
     
     
         110 . The method of  claim 109 , wherein the cold crucible induction furnace operates at a frequency of about 0.22 megahertz, 0.32 megahertz, 0.44 megahertz, or 1.76 megahertz.