Burner with a perforated flame holder support structure

Abstract

A furnace has a fuel and oxidant source to create a flow of combustible fuel and oxidant mixture, a perforated flame holder on which the flow impinges, and a support structure to support the perforated flame holder in a position where it at least partially contains combustion of the fuel and oxidant mixture. The support structure mechanically engages with the interior of the furnace to support the perforated flame holder, which may be movable within the furnace via a mechanism to optimize combustion or reduce NOx. The support may contain fluid coolant. The perforated flame holder may be moved into and out of a combustion region.

What is claimed is: 
     
         1 . A furnace, comprising:
 a fuel and oxidant source configured to output fuel and oxidant,   a perforated flame holder configured to hold a combustion reaction supported by the fuel and oxidant source; and   a support structure configured to hold the perforated flame holder in alignment with the fuel and oxidant output by the fuel and oxidant source;   wherein the support structure comprises a mechanical coupling between the perforated flame holder and an attachment point of the furnace.   
     
     
         2 . The furnace of  claim 1 , wherein the mechanical coupling comprises a cooling fluid channel configured to convey cooling fluid to at least a portion of the support structure, an actuator configured to cause a position change of at least a portion of the support structure, or a cooled actuator configured to cause a position change of at least a portion of the support structure. 
     
     
         3 . The furnace of  claim 1 , wherein the perforated flame holder is configured by thermal and structural reaction parameters thereof to contain a flame therein at the location, when the fuel and oxidant has a predetermined mix ratio and a predetermined velocity, and the fuel has a predetermined heat value. 
     
     
         4 . The furnace of  claim 1 , wherein the perforated flame holder has a substantially uniform thickness between a first flame holder surface and a second flame holder surface. 
     
     
         5 . The furnace of  claim 1 , wherein the support structure further comprises a strut extending from an interior surface of the furnace to the perforated flame holder through an intervening space. 
     
     
         6 . The furnace of  claim 5 , wherein the strut is canted in a direction opposite to a velocity of the fuel and oxidant from the fuel and oxidant source. 
     
     
         7 . The furnace of  claim 1 , wherein the support structure further comprises a fastener attached to a wall of the furnace. 
     
     
         8 . The furnace of  claim 7 , wherein the fastener further comprises a weld. 
     
     
         9 . The furnace of  claim 7 , wherein the fastener further comprises a bolt or stud. 
     
     
         10 . The furnace of  claim 2 , wherein the support structure further comprises a tension member. 
     
     
         11 . The furnace of  claim 2 , wherein the support structure further comprises a compression member. 
     
     
         12 . The furnace of  claim 1 , wherein the support structure further comprises a rail. 
     
     
         13 . The furnace of  claim 2 , wherein the attachment point of the furnace further comprises at least one furnace tube with which the support structure is mechanically coupled. 
     
     
         14 . The furnace of  claim 13 , wherein the furnace further comprises a fire-tube boiler and the furnace tube further comprises the attachment point. 
     
     
         15 . The furnace of  claim 2 , wherein the support structure is attachable to and detachable from the furnace at the attachment point. 
     
     
         16 . The furnace of  claim 1 , wherein the furnace further comprises a burner tile, and the support structure is configured to couple to the burner tile. 
     
     
         17 . The furnace of  claim 1 , wherein an interior surface of the furnace further comprises an area that faces into, or is adjacent to an opening into or out of, an interior space of the furnace, and wherein the support structure engages with a plate to which the fuel and oxidant source is mounted, and the plate is configured to the opening. 
     
     
         18 . The furnace of  claim 1 , wherein the support structure further comprises a coolant space therein, the coolant space being bounded by a fluid-containment barrier;
 the coolant space being separated from combustion by the fluid-containment barrier.   
     
     
         19 . The furnace of  claim 18 , further comprising coolant disposed in the coolant space. 
     
     
         20 . The furnace of  claim 18 , wherein the support structure is metallic and the perforated flame holder is non-metallic. 
     
     
         21 . The furnace of  claim 18 , wherein the fluid-containment barrier further comprises a fluid connection between the coolant space and a space outside of the perforated flame holder. 
     
     
         22 . The furnace of  claim 21 , wherein the fluid connection further comprises a coolant conduit passing through a wall of the furnace. 
     
     
         23 . The furnace of  claim 22 , wherein the support structure further comprises the coolant conduit. 
     
     
         24 . The furnace of  claim 22 , wherein an attachment point of the furnace comprises the coolant conduit. 
     
     
         25 . The furnace of  claim 24 , wherein the coolant conduit further comprises a hollow bolt passing through the wall of the furnace. 
     
     
         26 . The furnace of  claim 21 , further comprising a heat radiator located in the space outside of the perforated flame holder and a space outside of the furnace, and wherein the radiator is fluid-coupled to the coolant space by the fluid connection. 
     
     
         27 . A method of removing heat from a furnace, the furnace comprising:
 a fuel and oxidant source configured to output fuel and oxidant,   a perforated flame holder configured to hold a combustion reaction supported by the fuel and oxidant source; and   a support structure configured to hold the perforated flame holder in alignment with the fuel and oxidant output by the fuel and oxidant source, the support structure further comprising a coolant space therein, the coolant space being bounded by a fluid-containment barrier and separated from combustion by the fluid-containment barrier;   the method comprising:   supporting the perforated flame holder to receive a flow of fuel and oxidant with a flame holder support structure;   holding a combustion reaction supported by the fuel and oxidant with the perforated flame holder; and   cooling the perforated flame holder support structure by placing the flame holder support structure in contact with a fluid coolant having a coolant temperature lower than a combustion temperature.   
     
     
         28 . The method of removing heat from the perforated flame holder of  claim 27 , further comprising moving the fluid coolant relative to the perforated flame holder support structure. 
     
     
         29 . The method of removing heat from the perforated flame holder of  claim 27 , wherein the fluid coolant includes air. 
     
     
         30 . The method of removing heat from the perforated flame holder of  claim 27 , wherein the fluid coolant includes a liquid. 
     
     
         31 . The method of removing heat from the perforated flame holder of  claim 30 , further comprising boiling the liquid within the coolant space. 
     
     
         32 . The method of removing heat from the perforated flame holder of  claim 27 , wherein the fluid coolant includes sodium. 
     
     
         33 . The method of removing heat from the perforated flame holder of  claim 27 , further comprising moving the coolant to a heat radiator outside of the furnace. 
     
     
         34 . The furnace of  claim 1 , wherein the support structure further comprises a mechanism configured to move the perforated flame holder relative to the furnace and/or the fuel and oxidant source. 
     
     
         35 . The furnace of  claim 34 , wherein the mechanism is configured to move the perforated flame holder into and/or out of a cooling region wherein the perforated flame holder and/or the support structure is cooled. 
     
     
         36 . The furnace of  claim 35 , wherein the mechanism moves the perforated flame holder continually or continuously over a path that passes through a fuel and oxidant-impingement region and the cooling region. 
     
     
         37 . The furnace of  claim 34 , wherein the support structure further comprises a rail, and the perforated flame holder is mounted on the rail by a slider mechanism. 
     
     
         38 . The furnace of  claim 34 , wherein the perforated flame holder revolves or rotates. 
     
     
         39 . The furnace of  claim 38 , wherein the perforated flame holder further comprises a belt of hinged links. 
     
     
         40 . The furnace of  claim 34 , wherein the mechanism is configured to vary a distance between the perforated flame holder and the fuel and oxidant source by moving the perforated flame holder, relative to the furnace, in a direction that is parallel to a flow of fuel and oxidant and/or transverse to a first flame holder surface. 
     
     
         41 . The furnace of  claim 40 , wherein the fuel and oxidant source is non-movable relative to the furnace. 
     
     
         42 . The furnace of  claim 34 , wherein the mechanism moves the perforated flame holder, and further comprising an additional mechanism that moves the fuel and oxidant source relative to the furnace. 
     
     
         43 . The furnace of  claim 34 , wherein the support structure is mounted on a burner tile, and the mechanism moves the perforated flame holder relative to the burner tile. 
     
     
         44 . The furnace of  claim 34 , wherein the mechanism puts the support structure into sliding or rolling contact with an interior surface of the furnace. 
     
     
         45 . The furnace of  claim 44 , wherein the contact is made at least partially by a wheel comprised in the mechanism. 
     
     
         46 . The furnace of  claim 44 , wherein the mechanism further comprises a rail mounted on the interior surface of the furnace and the support structure slides or rolls on the rail. 
     
     
         47 . The furnace of  claim 46 , wherein the rail is substantially parallel to an axis of a cylindrical or prismatic portion of the interior surface. 
     
     
         48 . The furnace of  claim 34 , wherein at least one of the support structure or the mechanism further comprises a compression member in contact with an attachment point of the furnace. 
     
     
         49 . The furnace of  claim 34 , wherein at least one of the support structure or the mechanism further comprises a tension member in contact with an attachment point of the furnace. 
     
     
         50 . The furnace of  claim 34 , wherein the mechanism rotates the perforated flame holder within the furnace. 
     
     
         51 . The furnace of  claim 50 , wherein the perforated flame holder is rotated about an axis that that is not parallel to a direction of flow of fuel and oxidant. 
     
     
         52 . The furnace of  claim 34 , wherein the support structure engages with a mounting plate to which the fuel and oxidant source is mounted, and the support structure further comprises the mechanism. 
     
     
         53 . The furnace of  claim 52 , wherein the support structure further comprises a flange disposed between the plate and the interior surface. 
     
     
         54 . The furnace of  claim 34 , wherein the mechanism further comprises an actuator. 
     
     
         55 . The furnace of  claim 54 , wherein the actuator further comprises a motor. 
     
     
         56 . The furnace of  claim 34 , wherein the mechanism further comprises a screw and/or a gear. 
     
     
         57 . The furnace of  claim 34 , wherein the mechanism further comprises a feedback loop further comprising a processor and a sensor;
 wherein the perforated flame holder is configured by thermal and structural reaction parameters thereof to contain a flame therein when located at a distance from the fuel and oxidant source at which the flow has a predetermined velocity and a predetermined mix ratio, and the fuel has a predetermined heat value; and   wherein the feedback loop varies the distance under control of the processor to maintain the flame within the perforated flame holder.   
     
     
         58 . A method of reducing combustion emissions emitted by a furnace, the furnace comprising:
 configuring a perforated flame holder by thermal and structural reaction parameters thereof to contain a flame therein at a position, when a fuel-oxidant mixture from the fuel and oxidant source has a predetermined mix ratio and a predetermined velocity, and the fuel has a predetermined heat value;   providing an electronic feedback device operatively coupled to a flame sensor and the mechanism; and   moving the perforated flame holder, under control of the feedback device reacting to signals from the flame sensor, to contain the flame inside the perforated flame holder and/or to reduce emissions.   
     
     
         59 . The method of reducing combustion emissions of  claim 58 , wherein the electronic feedback device further comprises a processor running software embodied in a non-transitory medium. 
     
     
         60 . The method of removing heat from the perforated flame holder of  claim 58 , comprising:
 using the mechanism to move at least a portion of the perforated flame holder between a flame and a cooling region.