Powdered fuels and powdered fuel dispersions

Abstract

A powdered fuel includes a powder including a material consisting of particles having a particle size distribution median and other statistical characteristics such that less than about 5% of the particles by weight have a size larger than an explosibility size limit for the material. The particle size distribution median and other statistical characteristics are selected based on the use of the powder as a substantially explosible fuel. In one embodiment the material is biomass. In other embodiments, the material is a metal material, a metal alloy, a metal oxide, a plastic material, or a hydrocarbon-bearing solid. A powdered fuel dispersion includes an oxidizing gas and a powdered fuel dispersed in the oxidizing gas at a ratio such that the powdered fuel dispersion is explosible. Proper control of the moving dispersion produces a stationary deflagrating wave that substantially consumes the fuel to produce energy.

1 . A powdered fuel comprising a powder comprising at least one biomass material, the powder consisting of particles having a particle size distribution median and other statistical characteristics such that:
 less than about 5% of the particles by weight have a size larger than an explosibility size limit for the biomass material;   wherein the particle size distribution median and other statistical characteristics are selected based on the use of the powder as a substantially explosible fuel.   
   
   
       2 . The powdered fuel of  claim 1 , wherein the powder comprises a first plurality of particles having a first particle size distribution median and other statistical characteristics and a second plurality of particles having a second particle size distribution median and other statistical characteristics different from the first particle size distribution median and other statistical characteristics, and wherein the first particle size distribution median and other statistical characteristics and the second particle size distribution median and other statistical characteristics are selected based on the use of the powder as the substantially explosible fuel. 
   
   
       3 . The powdered fuel of  claim 2 , wherein the second plurality of particles are a powdered coal material. 
   
   
       4 . The powdered fuel of  claim 1 , wherein the powder is a blended powdered fuel of two or more materials. 
   
   
       5 . The powdered fuel of  claim 4 , wherein the blended powder has 10% to 90% coal. 
   
   
       6 . The powdered fuel of  claim 1 , wherein the biomass material is selected from the group consisting of crops, wastes and residues, starch crops, grains, rice, barley, rye, oats, soybean, maize and wheat, sugar cane, sugar, cocoa bean, sugar crops, corn, grasses, switchgrass, Miscanthus grass, elephant grass, tall fescue, prairie grass, Reed canarygrass, Giant reed, cotton, seeds and husks, seaweed, water hyacinth, algae, microalgae, herbaceous and woody energy crops, wood chips, bamboo, wood, stem wood, cellulose, and lignin, hardwoods, American sycamore, black locust, eucalyptus, hybrid poplar, hybrid willow, silver maple, softwoods, cedar, pine, Monterey pine, fishmeal, fat, whey, agricultural wastes, rice straw, chaff, wheat straw, sugar cane bagasse, corn stover, corn stalks, and forestal wastes, sawdust, shavings, lumber wastes, pulp and pulp waste, mill wastes, thinned woods, brush, municipal and industrial solid wastes, construction wastes, demolition wood wastes, urban wood wastes, yard wastes, agricultural residues, livestock wastes, dry manure solids, poultry wastes, intermediate enzymatic and acid hydrolysis bio-solid byproducts, waste solids from biological processes of ethanol fermentation, methane production and anaerobic digestion. 
   
   
       7 . The powdered fuel of  claim 1 , wherein the powder comprises at least one material selected from the group consisting of boron, calcium, phosphorus, magnesium, silicon, sulfur, aluminum, iron, titanium, tantalum, zirconium, zinc, and compounds and alloys thereof, bronze, titanium dioxide, coal, ultra clean coal, metal, plastic, sulfur dust, phosphorus dust, polyester dust, a hydrocarbon-bearing solid, polypropylene, polystyrene, acrylonitrile butadiene styrene, polyethylene terephthalate, polyester, polyamides, polyurethanes, polycarbonate, polyvinylidene chloride, polyethylene, polymethyl methacrylate, polytetrafluoroethylene, polyetheretherketone, polyetherimide, phenolics, urea-formaldehyde, melamine formaldehyde, and polylactic acid. 
   
   
       8 . The powdered fuel of  claim 1 , wherein:
 less than about 5% of the particles by weight have a size larger than or equal to 80 mesh;   at least about 15% of the particles by weight have a size smaller than 200 mesh; and   the particle size distribution median and other statistical characteristics are selected based on the use of the powder as a substantially explosible fuel.   
   
   
       9 . The powdered fuel of  claim 8 , wherein less than about 5% of the particles by weight have a size larger than or equal to 200 mesh. 
   
   
       10 . The powdered fuel of  claim 9 , wherein less than about 1% of the particles by weight have size larger than or equal to 200 mesh. 
   
   
       11 . The powdered fuel of  claim 9 , wherein:
 at least 50% of the particles by weight have a size smaller than 325 mesh;   at least 15% of the particles by weight have a size smaller than 400 mesh; and   the particle size distribution median and other statistical characteristics are selected based on the use of the powder as a substantially explosible fuel.   
   
   
       12 . The powdered fuel of  claim 11 , wherein at least 70% of the particles by weight have a size smaller than 325 mesh. 
   
   
       13 . The powdered fuel of  claim 11 , wherein at least 30% of the particles by weight have a size smaller than 400 mesh. 
   
   
       14 . The powdered fuel of  claim 8 , wherein at least 30% of the particles by weight have a size smaller than 200 mesh. 
   
   
       15 . The powdered fuel of  claim 14 , wherein at least 30% of the particles by weight have a size smaller than 325 mesh. 
   
   
       16 . The powdered fuel of  claim 15 , wherein at least 40% of the particles by weight have a size smaller than 200 mesh. 
   
   
       17 . The powdered fuel of  claim 8 , wherein less than 1% of the particles by weight have a size larger than or equal to 80 mesh. 
   
   
       18 . The powdered fuel of  claim 17 , wherein substantially all of the particles have a size smaller than or equal to 80 mesh. 
   
   
       19 . The powdered fuel of  claim 8 , wherein the powder is dispersed in an oxidizing gas at an explosible ratio of four to fifty grams of powder to one cubic foot of oxidizing gas. 
   
   
       20 . A powdered fuel comprising at least one powdered material, the powdered material consisting of particles having a particle size distribution median and other statistical characteristics such that:
 less than about 5% of the particles by weight have a size larger than an explosibility size limit for the powdered material;   wherein the particle size distribution median and other statistical characteristics are selected based on the use of the powder as a substantially explosible fuel; and   wherein the powdered material is selected from the group consisting of a metal material, a metal alloy, a metal compound, a plastic material, and a hydrocarbon-bearing solid.   
   
   
       21 . The powdered fuel of  claim 20 , wherein:
 less than about 5% of the particles by weight have a size larger than or equal to 200 mesh;   at least about 25% of the particles by weight have a size smaller than 325 mesh; and   the particle size distribution median and other statistical characteristics are selected based on the use of the powder as a substantially explosible fuel.   
   
   
       22 . The powdered fuel of  claim 21 , wherein the powdered material comprises at least one material selected from the group consisting of boron, calcium, phosphorus, magnesium, silicon, sulfur, aluminum, iron, titanium, tantalum, zirconium, zinc, and compounds and alloys thereof, bronze, titanium dioxide, metal, plastic, sulfur dust, phosphorus dust, polyester dust, a hydrocarbon-bearing solid, polypropylene, polystyrene, acrylonitrile butadiene styrene, polyethylene terephthalate, polyester, polyamides, polyurethanes, polycarbonate, polyvinylidene chloride, polyethylene, polymethyl methacrylate, polytetrafluoroethylene, polyetheretherketone, polyetherimide, phenolics, urea-formaldehyde, melamine formaldehyde, and polylactic acid. 
   
   
       23 . A travelling powdered fuel dispersion comprising:
 an oxidizing gas; and   a powdered fuel dispersed in the oxidizing gas at an explosible ratio such that the powdered fuel dispersion is explosible, the powdered fuel comprising at least one material comprising a powder consisting of particles having a particle size distribution median and other statistical characteristics such that:
 less than about 5% of the particles by weight have a size larger than an explosibility size limit for the material; 
 wherein the particle size distribution median and other statistical characteristics are selected based on the use of the powder as a substantially explosible fuel. 
   
   
   
       24 . The powdered fuel dispersion of  claim 23 , wherein the explosible ratio is between four and fifty grams of powder to one cubic foot of oxidizing gas. 
   
   
       25 . The powdered fuel dispersion of  claim 24 , wherein the oxidizing gas is air. 
   
   
       26 . The powdered fuel dispersion of  claim 24 , wherein:
 less than about 5% of the particles by weight have a size larger than or equal to 80 mesh;   at least about 15% of the particles by weight have a size smaller than 200 mesh; and   the particle size distribution median and other statistical characteristics are selected based on the use of the powder as a substantially explosible fuel.   
   
   
       27 . The powdered fuel dispersion of  claim 26 , wherein less than about 1% of the particles by weight have size larger than or equal to 200 mesh. 
   
   
       28 . The powdered fuel dispersion of  claim 26 , wherein at least about 30% of the particles by weight have a size smaller than 325 mesh. 
   
   
       29 . The powdered fuel dispersion of  claim 26 , wherein at least 30% of the particles by weight have a size smaller than 200 mesh and the particle size distribution is selected based on the use of the powder as the substantially explosible fuel. 
   
   
       30 . The powdered fuel dispersion of  claim 26 , wherein the powdered fuel has a particle size distribution wherein:
 less than 5% of the particles by weight have a size larger than or equal to 200 mesh;   at least 50% of the particles by weight have a size smaller than 325 mesh;   at least 15% of the particles by weight have a size smaller than 400 mesh; and   the particle size distribution median and other statistical characteristics are selected based on the use of the powder as a substantially explosible fuel.