Low NOx burner for ethylene cracking furnaces and other heating applications

Patent metadata

Field	Value
Publication number	US-10240779-B2
Application number	US-201715674454-A
Country	US
Kind code	B2
Filing date	Aug 10, 2017
Priority date	Nov 8, 2013
Publication date	Mar 26, 2019
Grant date	Mar 26, 2019

Abstract

A burner assembly for and method of producing ethylene having a mechanism to inject either primary fuel, staged fuel, or both by premix methods before combustion in a furnace. The burner assembly has at least one premix injection assembly for either exclusively primary fuel or exclusively staged fuel injection paired with a nozzle mix injection or injection means for primary and staged fuel both by premix methods. The primary fuel premix assembly associates with a burner tile that consists of multiple inlets and outlets connected by venturi channels to direct and combine combustion air and staged fuel coming from staged fuel orifice spuds. Primary fuel and combustion air are mixed in a premix assembly and directed inside the furnace, and above the burner tile to complete the reaction with the staged fuel and combustion air mixture in a combustion zone inside of the furnace.

First claim

The invention claimed is:

1. A burner assembly for a furnace, comprising:
at least one primary fuel tip associated with a burner tile;
at least one staged fuel orifice spud associated with said burner tile;
said burner tile including:
a connective opening for the at least one primary fuel tip;
a discharge opening to discharge primary fuel in a furnace;
multiple staged fuel inlets to receive staged fuel from the at least one staged fuel orifice spud;
multiple angled discharge outlets, wherein said discharge outlets are respectively connected to said staged fuel inlets by way of multiple venturi channels; and
multiple combustion air inlets to receive combustion air from outside of said furnace, wherein said multiple combustion air inlets fluidly connect to said multiple venturi channels and to said multiple discharge outlets.

2. The burner assembly of claim 1 , wherein said multiple discharge outlets release staged fuel, combustion air, and combustion products into a furnace.

3. A burner assembly for a furnace, comprising:
at least one primary premix venturi and tip assembly associated with and extending outward from a burner tile;
at least one staged fuel orifice spud associated with said burner tile;
said burner tile including:
a connective opening for communication with the at least one venturi and tip assembly;
a discharge opening for said connective opening;
multiple staged fuel inlets to receive staged fuel from the at least one staged fuel spud;
multiple angled discharge outlets, wherein said discharge outlets are respectively connected to said staged fuel inlets by way of multiple venturi channels; and
multiple combustion air inlets to receive combustion air from outside of said furnace, wherein said multiple combustion air inlets connect to said multiple venturi channels, respectively.

4. The burner assembly of claim 3 , wherein said premix venturi and tip assembly comprises:
an elongated venturi mixing chamber;
an inlet in fluid communication with said venturi mixing chamber;
a primary fuel orifice spud for introduction of primary fuel into said inlet;
a primary fuel riser in fluid communication with a primary fuel orifice spud; and
a primary mixer tip in fluid communication with said venturi mixing chamber.

5. The burner assembly of claim 4 , wherein said primary mixer tip of said premix venturi and tip assembly sits within said burner tile and is positioned such that a primary fuel and combustion air mixture may be released through said discharge opening.

6. The burner assembly of claim 4 , wherein said multiple staged fuel inlets of said burner tile receive staged fuel from the at least one staged fuel orifice spud.

7. The burner assembly of claim 4 , wherein said multiple angled discharge outlets release staged fuel, combustion air, and combustion products inside a furnace.

8. A method of ethylene production in a furnace with a burner assembly that includes at least one premix venturi and tip assembly, at least one primary fuel orifice spud, at least one staged fuel orifice spud, and a burner tile for combusting fuel in a furnace space, comprising:
injecting primary fuel through the premix venturi and tip assembly by way of a primary fuel orifice spud;
inducing approximately ninety percent ( 90 %) of stoichiometric air required for combusting the primary fuel into said premix venturi and tip assembly;
mixing the primary fuel with said stoichiometric air;
discharging a uniform mixture of said primary fuel and said stoichiometric air through a primary mixer tip and into said furnace space;
circulating combustion products from furnace through passageways of burner tile;
discharging staged fuel into the burner tile through the at least one staged fuel orifice spud wherein the staged fuel leads into multiple venturi channels;
conducting combustion air through multiple combustion air inlets cast within said burner tile;
inducing combustion products from said furnace and into said multiple venturi channels;
mixing of the combustion products and said staged fuel with combustion air within said burner tile and before exiting said burner tile; and
injecting a mixture of the combustion products, the staged fuel, and combustion air at a slight angle towards the uniform, fuel rich mixture of primary fuel and combustion air.

9. The method of claim 8 , wherein said uniform, fuel rich mixture of primary fuel and combustion air may burn under sub-stoichiometric conditions resulting in a low generation of NO x .

10. The method of claim 8 , wherein combustion of the uniform mixture occurs near to the burner tile.

11. The method of claim 8 , wherein said primary fuel and said secondary fuel are both natural gas fuel.

Assignees

• Honeywell Int Inc

Inventors

• Martin Richard Ray

Classifications

• F23C2201/20

  Burner staging · CPC title

• F23C2900/06041

  Staged supply of oxidant · CPC title

• F23D14/10

  with elongated tubular burner head · CPC title

• F23D14/04

  induction type, e.g. Bunsen burner · CPC title

• F23D14/64 Primary

  with injectors · CPC title