Continuous real time heating value (BTU)/Coal flow balancing meter

Abstract

A method and an apparatus for continuous real time heating value/coal flow balancing of coal from a coal feeder to a burner. The apparatus includes a dual-energy Gamma Attenuation (DGA)/multi-energy Gamma Attenuation (MGA) device for measuring coal quality at a specific location between the coal silo and the mill in a coal fired plant in order to control the individual burner stoichiometries according to the measured coal quality. By strategically placing the DGA/MGA device, continuous accurate real-time coal quality information is accomplished for making individual adjustments in order to improve stoichiometry to optimize performance of the system.

1 . A device for continuous real time heating value/coal flow balancing of coal from a coal feeder to a burner, said device being used in association with a coal burning system including at least a coal feeder, a mill for pulverizing the coal, at least one damper for controlling oxygen (O 2 ) introduced in the coal, and at least one burner for burning coal processed through the at least one damper, said device comprising: 
 a dual-energy Gamma Attenuation (DGA)/multi-energy Gamma Attenuation (MGA) device for measuring the quality of coal, said DGA/MGA device being disposed between the coal feeder and the mill, said DGA/MGA device measuring coal as the coal passes between the coal feeder and the mill, said DGA/MGA device including: 
 at least one DGA/MGA source positioned proximate to the coal at a location between the coal feeder and the mill;  
 at least one DGA/MGA detector positioned to detect high energy gamma rays emitted from the coal; and  
 a DGA/MGA data acquisition unit for reading output from said at least one DGA/MGA detector; and  
   a processor in communication with said DGA/MGA data acquisition unit for processing, said processor further in communication with the at least one damper, said processor being adapted to control at least one damper in response to the coal quality information.    
   
   
       2 . The device of  claim 1  wherein said at least one DGA/MGA source and said at least one DGA/MGA detector are each placed in proximity to the coal feeder for analyzing coal before the coal is delivered to the mill.  
   
   
       3 . The device of  claim 1  wherein a delay is determined for a distance between said DGA/MGA device and the at least one damper, and wherein said processor signals the at least one damper in response to the coal quality information, said processor signaling the at least one damper after said delay whereby the at least one damper is adjusted according to the coal quality information for a selected volume of coal as the selected volume of coal is processed through the at least one damper.  
   
   
       4 . A coal fire burning system providing continuous real time heating value/coal flow balancing of coal, said system comprising: 
 a coal feeder for receiving coal and supplying coal to said system;    a mill for pulverizing coal received from said coal feeder;    at least one damper for controlling oxygen (O 2 ) introduced in the pulverized coal;    at least one burner for burning coal processed through the at least one damper, each of said at least one burner being adapted to receive a mixture of at least coal and O 2  from one of said at least one damper;    a dual-energy Gamma Attenuation (DGA)/multi-energy Gamma Attenuation (MGA) device for measuring the quality of coal, said DGA/MGA device being disposed between said coal feeder and said mill, said DGA/MGA device measuring coal as the coal passes between said coal feeder and said mill, said DGA/MGA device including: 
 at least one DGA/MGA source positioned proximate to the coal at a location between said coal feeder and said mill;  
 at least one DGA/MGA detector positioned to detect high energy gamma rays emitted from the coal; and  
 a DGA/MGA data acquisition unit for reading output from said at least one DGA/MGA detector; and  
   a processor in communication with said DGA/MGA data acquisition unit for processing, said processor further in communication with said at least one damper, said processor being adapted to control said at least one damper in response to the coal quality information, whereby a stoichiometry of each of said at least one burner is individually controlled and optimized.    
   
   
       5 . The device of  claim 4  wherein said at least one DGA/MGA source and said at least one DGA/MGA detector are each placed in proximity to said coal feeder for analyzing coal before the coal is delivered to said mill.  
   
   
       6 . The device of  claim 4  wherein a delay is determined for a distance between said DGA/MGA device and said at least one damper, and wherein said processor signals said at least one damper in response to the coal quality information, said processor signaling said at least one damper after said delay whereby said at least one damper is adjusted according to the coal quality information for a selected volume of coal as the selected volume of coal is processed through said at least one damper.  
   
   
       7 . A method for operating a coal fire burning system providing continuous real time heating value/coal flow balancing of coal, said system comprising a coal feeder; a mill for pulverizing coal; at least one damper for controlling oxygen (O 2 ) introduced in the pulverized coal; at least one burner for burning coal processed through the at least one damper; a dual-energy Gamma Attenuation (DGA)/multi-energy Gamma Attenuation (MGA) device for measuring the quality of coal including at least one DGA/MGA source positioned proximate to the coal at a location between said coal feeder and said mill, at least one DGA/MGA detector positioned to detect high energy gamma rays emitted from the coal, and a DGA/MGA data acquisition unit for reading output from said at least one DGA/MGA detector; and a processor in communication with the DGA/MGA data acquisition unit for processing, said processor further in communication with said at least one damper, said processor being adapted to control said at least one damper in response to the coal quality information, said method comprising the steps of: 
 (a) acquiring coal information; and    (b) determining whether the quality of coal presented to the individual burner requires a decrease in O 2  level;    (c) signaling said at least one damper to close according to the desired decrease in said O 2  level;    (d) determining whether the quality of coal presented to the individual burner requires an increase in O 2  level;    (e) signaling said at least one damper to open according to the desired increase in said O 2  level;    (f) repeating said steps of (b) acquiring coal information through (h) signaling said at least one damper.    
   
   
       8 . The method of  claim 7 , before said step of (a) acquiring coal information, further comprising the step of: 
 (a) determining a delay approximately equal to a time required for the coal to travel from said coal feeder to said at least one damper;    before said step of (c) signaling said at least one damper to close according to the desired decrease in said O 2  level, further comprising the step of:    (b) delaying for a time equal to said delay; and    before said step of (e) signaling said at least one damper to open according to the desired increase in said O 2  level, further comprising the step of:    (c) delaying for a time equal to said delay.