System and method for retrofitting a burner front and injecting a second fuel into a utility furnace

Abstract

This disclosure may relate generally to systems, devices, and methods for a injecting a compound through a sootblower, burner or other utility furnace hardware, such that the compound can be delivered to targeted areas on the inside of a utility furnace. In one embodiment, the compound is a chemical for improving environmental controls. In another embodiment, the compound is a fuel. In that embodiment, compound can facilitate retrofitting a burner to a dual fired utility furnace. In another embodiment, the compound is a chemical for removing slag from the furnace.

I claim: 
     
         1 . A utility furnace comprising:
 a burner;   a delivery mechanism, wherein the delivery mechanism is configured to deliver combustion air into the utility furnace, wherein the delivery mechanism is configured to deliver combustion air into the utility furnace in the vicinity of the burner, wherein the combustion air comprises one of primary air, secondary air and tertiary air;   a fuel source provided to the burner, wherein the fuel source is a first fuel type and is the primary source of fuel to the utility furnace; and   a compound source, connected to the delivery mechanism, wherein the compound source is configured to supply a compound into the combustion air in the delivery mechanism.   
     
     
         2 . The utility furnace of  claim 1 , wherein the compound is a second fuel type different from the first fuel type. 
     
     
         3 . The utility furnace of  claim 2 , wherein the second fuel type is one of: a liquid and a gas. 
     
     
         4 . The utility furnace of  claim 2 , wherein the second fuel type is natural gas liquid (NGL). 
     
     
         5 . The utility furnace of  claim 2 , wherein the second fuel type is liquefied natural gas (LNG). 
     
     
         6 . The utility furnace of  claim 2 , wherein the first fuel type is supplied to the utility furnace in a coal burner tube and wherein the second fuel type is supplied to the utility furnace through a second tube located outside of and proximate to the coal burner tube, wherein both the coal burner tube and the second tube are located in a windbox of the burner front. 
     
     
         7 . A method of retrofitting a utility furnace, wherein the utility furnace has a burner front, wherein the burner front fires the utility furnace with a first fuel type, and wherein the burner front supplies combustion air associated with the combustion of the first fuel type, wherein the combustion air comprises at least one of: primary air, secondary air, and tertiary air, the method comprising:
 connecting a source of a second fuel type to the burner front, wherein the connection is configured to introduce the second fuel type into the combustion air; and   wherein the first fuel type is a different type of fuel from the second fuel type.   
     
     
         8 . The method of  claim 7 , wherein the utility furnace is a coal fired furnace and the first fuel type is coal. 
     
     
         9 . The method of  claim 8 , wherein the second fuel type is one of: a liquid and a gas. 
     
     
         10 . The method of  claim 9 , wherein the second fuel type is natural gas liquid (NGL). 
     
     
         11 . The method of  claim 9 , wherein the second fuel type is liquefied natural gas (LNG). 
     
     
         12 . The method of  claim 8 , wherein the second fuel type is introduced directly into the combustion air. 
     
     
         13 . The method of  claim 8 , wherein the second fuel type is introduced indirectly into the combustion air. 
     
     
         14 . The method of  claim 8 , wherein the combustion air is primary air. 
     
     
         15 . A method of injecting a compound into a utility furnace comprising:
 delivering a compound into the utility furnace by injecting the compound into a delivery mechanism conveying a combustion air, wherein the combustion air is one of primary air, secondary air, and tertiary air, wherein the compound comprises a fuel that is not a primary fuel for firing the utility furnace.   
     
     
         16 . The method of  claim 15 , wherein the delivery mechanism is a burner front for the utility furnace, wherein the burner front comprises the burner and wherein the burner front is configured to mix the compound with the combustion air. 
     
     
         17 . The method of  claim 15 , wherein the fuel is natural gas liquid (NGL) and the primary fuel is coal. 
     
     
         18 . The method of  claim 15 , wherein the fuel is liquefied natural gas liquid (LNG) and the primary fuel is coal. 
     
     
         19 . The method of  claim 15 , wherein the fuel is one of a liquid and a gas, and wherein the primary fuel is coal.