Burners for conversion of methane to olefins, aromatics, and nanoparticles

Abstract

Embodiments of the present disclosure describe burner configurations used in an industrial process to convert methane to olefins, aromatics, and nanoparticles/nanomaterials. Both a vitiated coflow burner and piloted turbulent burner with inhomogeneous inlets are disclosed.

What is claimed is: 
     
         1 . A burner for converting injected methane to olefins, aromatics and nanoparticles/nanomaterials, comprising:
 a plate through which a coflow gas passes including a porous plate or catalytic monolith, with a coflow flame established above the plate;   a central tube passing through the plate and having a tip through which methane exits; two concentric tubes with an annulus that supplies premixed methane and oxygen via the porous plate or catalytic monolith;   a tube positioner for varying an offset height of the tube tip relative to the plate; and a controller for adjusting the offset height of the tube tip based on material inputs or desired output yield.   
     
     
         2 . The burner of  claim 1  further comprising an exit collar surrounding the plate, with said exit collar establishing a shear boundary of combustion products. 
     
     
         3 . The burner of  claim 1 , wherein the plate includes a catalytic monolith. 
     
     
         4 . The burner of  claim 3 , wherein the catalytic monolith is a ceramic monolith coated by catalytic materials. 
     
     
         5 . The burner of  claim 3 , wherein the catalytic monolith is a straight-channel monolith. 
     
     
         6 . The burner of  claim 1 , wherein the plate includes the porous plate. 
     
     
         7 . The burner of  claim 6 , wherein the porous plate is a perforated plate, a porous metal, or a metal screen. 
     
     
         8 . A method of controlling secondary reactions of a burner of combustion products using injected methane, the method comprising:
 passing a premixed vitiated coflow of gas through a porous plate or catalytic monolith to establish a premixed flame, wherein the porous plate or catalytic monolith is supplied with the premixed vitiated coflow of gas by an annulus of a coflow burner comprising two concentric tubes, wherein the central tube has a tip;   establishing a jet flame in coaxial flow of hot combustion products from the premixed flame, said jet flame established by gas exiting from the central tube of the two concentric tubes;   providing a tube positioner to translate the tip of the central tube to an offset height relative to the porous plate or catalytic monolith; and   controlling the tube positioner to vary the offset height of the tip of the central tube in a dynamic manner based on chemical inputs, with the controlling step resulting in different secondary reactions of the hot combustion products from the premixed flame, with the gas exiting from the central tube.   
     
     
         9 . The method of  claim 8 , wherein the central tube is a blunt-tipped tube and the gas exiting the central tube is methane. 
     
     
         10 . The method of  claim 8 , wherein the coflow gas is a combination of methane and oxygen. 
     
     
         11 . The method of  claim 8 , wherein offset height of the central tube tip is controlled to provide both a methane/oxygen combustion process and subsequent pyrolysis of methane to form olefins, aromatics or nanoparticles. 
     
     
         12 . The method of  claim 11 , wherein the pyrolysis of methane forms nanoparticles selected from carbon black and carbon nanotubes. 
     
     
         13 . The method of  claim 11 , wherein the pyrolysis of methane forms ethylene or acetylene. 
     
     
         14 . The method of  claim 11 , wherein the pyrolysis of methane forms benzene or naphthalene. 
     
     
         15 . The method of  claim 8 , wherein the plate includes a catalytic monolith. 
     
     
         16 . The method of  claim 15 , wherein the catalytic monolith is a ceramic monolith coated by catalytic materials. 
     
     
         17 . The method of  claim 8 , wherein the plate includes the porous plate. 
     
     
         18 . The method of  claim 17 , wherein the porous plate is a perforated plate, a porous metal, or a metal screen.