Method for oxygen enriched low NOx, low CO2 and low CO combustion of pulverized solid fuel suspended in a preheated secondary fluid hydrocarbon fuel

Abstract

A method and combination of devices for oxygen enriched, low-NO.sub.x, low CO.sub.2 and low CO combustion of a pulverized solid fuel, wherein the pulverized solid fuel is suspended and substantially preheated in a secondary fluid hydrocarbon fuel which includes natural gas, LN and LP gas or fuel oil, and wherein said preheated fuel mixture may be combined with substantially precooled combustion air for ignition, which process will significantly improve the combustion efficiency and reduction of harmful emissions during the combustion process in a burner of a combustion mechanism.

1 - 8 . (canceled)  
   
   
       9 . A method for reducing harmful emissions of NO.sub.x, SO.sub.2, CO.sub.2, CO, Mercury and Particulates, and for improving combustion air oxygen volume percentage which significantly improves combustion efficiency during the process of combustion of solid hydrocarbon fuels, including lignite, bituminous- and sub-bituminous coals, petroleum coke and biomass products, comprising: 
 a) pulverizing a primary solid hydrocarbon fuel to a particle size less than 75 microns or to a micron size which allows suspension and fluidization of the powderized solid hudrocarbon fuel in a secondary transport fluid hydrocarbon fuel;    b) suspending said solid pulverized primary fuel in the secondary transport fluid comprising a hydrocarbon fuel, including natural gas, liquid natural gas, propane gas, liquid propane gas, or liquid fuel oil, in order to create a fuel mixture of primary pulverised fuel and secondary fluid transport fuel;    c) transporting said fluid fuel mixture through a fuel delivery conduit for combustion in a burner;    d) pre-heating said fluid fuel mixture, as it passes through a heat transfer assembly forming part of said fuel delivery conduit, to a temperature level ranging between ambient and the fuel mixture's auto-ignition temperature;    e) transporting a temperature controlled stream of combustion air of sufficient volume in a combustion air delivery conduit for efficient matching with the fuel volume and combustion in a burner;    f) transporting combustion products or combustion exhaust gases generated during the combustion process through a combustion product exit conduit provided for such purpose;    
   
   
       10 . A method according to  claim 9 , wherein said fuel mixture is turbulated in a fuel mixture turbulator forming part of the fuel heat transfer assembly, changing flow conditions from laminar to turbulent such as to improve the energy transfer aptitude of said fuel mixture.  
   
   
       11 . A method according to  claim 9 , wherein said fuel mixture is pre-heated through the direct conversion of waste energy or heat transferred from the combustion products or from other energy related to the combustion process.  
   
   
       12 . A method according to  claim 9 , wherein said stream of combustion air is pre-cooled as it passes through a heat transfer assembly forming part of said combustion air delivery conduit, to a temperature level ranging between ambient and minus 50 degrees Fahrenheit.  
   
   
       13 . A method according to  claim 9 , wherein said stream of combustion air is turbulated in a combustion air turbulator forming part of the combustion air delivery conduit, changing flow conditions from laminar to turbulent such as to improve the energy transfer aptitude of said combustion air stream.  
   
   
       14 . A method according to  claim 9 , wherein said stream of combustion air is pre-cooled through the direct conversion of waste energy or heat transferred from the combustion products or from other energy related to the combustion process.  
   
   
       15 . A method according to  claim 9 , wherein said combustion products of the combustion process are turbulated in a turbulator assembly forming part of the combustion product exit conduit or flue gas exit conduit, as the case may be, changing combustion product flow condition from laminar to turbulent such as to improve the transfer aptitude of the energy in said products.  
   
   
       16 . A device for reducing harmful emissions of NO.sub.x, SO.sub.2, CO.sub.2, CO, Mercury and Particulates, and for improving combustion air oxygen volume percentage which significantly improves combustion efficiency during the process of combustion of solid hydrocarbon fuels, including lignite, bituminous- and sub-bituminous coals, petroleum coke and biomass products, comprising: 
 a) providing a primary pulverized solid hydrocarbon fuel to a particle size less than 75 microns or to a micron size which allows suspension and fluidization of said primary solid fuel in a secondary transport fluid hydrocarbon fuel;    b) providing a secondary transport fluid fuel, including natural gas, liquid natural gas, propane gas, liquid propane gas, or liquid fuel oil, for suspension and transport of said solid pulverized fuel, creating a fluid hydrocarbon fuel mixture;    c) providing a fuel delivery conduit to transport said fluid hydrocarbon fuel mixture for combustion in a burner of a combustion mechanism;    d) providing means to pre-heat said fluid hydrocarbon fuel mixture, as it passes through a heat transfer assembly forming part of said fuel delivery conduit, to a temperature level ranging between ambient and the fuel mixture's auto-ignition temperature;    e) providing a specified volume of temperature controlled combustion air for transport in a combustion air delivery conduit connected to a burner for mixing with a designated volume of fuel mixture for efficient combustion in a combustion mechanism;    f) providing a combustion product exit conduit for the controlled transport and exit of combustion products or flue gases from the combustion mechanism.    
   
   
       17 . A device according to  claim 16 , wherein said fuel mixture is turbulated in a fuel mixture turbulator forming part of the fuel heat exchanger assembly, changing flow conditions from laminar to turbulent such as to improve the energy transfer aptitude of said fuel mixture.  
   
   
       18 . A device according to  claim 16 , wherein said fuel mixture is pre-heated through the direct conversion of waste energy or heat transferred from the combustion products or from other energy related to the combustion process.  
   
   
       19 . A device according to  claim 16 , which provides the means to cool said combustion air, as it passes through a heat transfer assembly forming part of the combustion air delivery conduit, to a temperature level ranging between ambient and minus 50 degrees Fahrenheit.  
   
   
       20 . A device according to  claim 16 , wherein said specified stream of combustion air is turbulated in a combustion air turbulator forming part of the combustion air delivery conduit, changing flow conditions from laminar to turbulent such as to improve the energy transfer aptitude of said combustion air stream.  
   
   
       21 . A device according to  claim 16 , wherein said stream of combustion air is pre-cooled through the direct conversion of waste energy or heat transferred from the combustion products or from other related energy of the combustion process.  
   
   
       22 . A device according to  claim 16 , wherein said combustion products of the combustion process are turbulated in a turbulator assembly forming part of the combustion product exit conduit, changing flow condition from laminar to turbulent such as to improve the transfer aptitude of the remaining energy in said combustion products or flue gases.