Systems and methods of pyrolyzing hydrocarbons
Systems and methods of pyrolyzing gaseous hydrocarbons include a reaction chamber and a plenum in fluid communication therewith. A light source directs electromagnetic radiation through a window into the reaction chamber. A first recirculation conduit connected between an offtake and an intake of the reaction chamber recirculates to the intake of the reaction chamber a portion of an aerosol product from the offtake of the reaction chamber. A filter operatively associated with the offtake of the reaction chamber receives un-recirculated amounts of the aerosol product and produces a retentate that includes particulate matter removed from the aerosol product. First and second gas separators operatively associated with the filter separate hydrogen and unreacted hydrocarbons from a filtrate of the filter. A second recirculation conduit connected between the second gas separator and the intake of the plenum recirculates unreacted hydrocarbons from the filtrate to the plenum.
1 . A method of pyrolyzing a hydrocarbon reactant material to produce hydrogen, comprising:
introducing the hydrocarbon reactant material into an intake of a plenum operatively associated with a reaction chamber, the reaction chamber defining a plurality of apertures therein that are in fluid communication with the plenum so that the hydrocarbon reactant material in the plenum is introduced into the reaction chamber at multiple locations;
introducing a particulate material into an intake of the reaction chamber, the particulate material mixing with the hydrocarbon reactant material from the plenum to form an aerosol;
exposing the aerosol to electromagnetic radiation sufficient to raise the temperature of the particulate material to a level sufficient to initiate pyrolyzation of the gaseous hydrocarbon reactant material to produce an aerosol product;
withdrawing the aerosol product via an offtake of the reaction chamber;
recirculating a portion of the withdrawn aerosol product to the intake of the reaction chamber, the recirculated portion of the aerosol product mixing with additional quantities of the gaseous hydrocarbon reactant material from the plenum, the recirculated portion of the aerosol product comprising the particulate material that is introduced into the intake of the reaction chamber;
filtering non-recirculated portions of the aerosol product to produce a filtrate substantially devoid of particulate matter;
separating a first gas constituent from the filtrate, the first gas constituent comprising hydrogen;
separating a second gas constituent from the filtrate, the second gas constituent comprising unreacted amounts of the gaseous hydrocarbon reactant material;
recirculating the separated second gas constituent to the inlet of the plenum; and
diffusing the hydrocarbon reactant material through a porous felt material positioned adjacent the plurality of apertures defined by the reaction chamber.
2 . The method of claim 1 , further comprising cooling the filtrate before performing at least one of said separating the first gas constituent and said separating the second gas constituent.
3 . The method of claim 2 , further comprising filtering the cooled filtrate to remove additional amounts of particulate matter retained in the filtrate before performing at least one of said separating the first gas constituent and said separating the second gas constituent.
4 . The method of claim 1 , wherein
said introducing the particulate material into the intake of the reaction chamber comprises introducing a particulate seed material into the intake of the reaction chamber; and
wherein said method further comprises terminating said providing the particulate seed material into the intake of the reaction chamber after said recirculating the portion of the withdrawn aerosol product to the intake of the reaction chamber.
5 . The method of claim 4 , wherein said introducing the particulate seed material into the reaction chamber comprises introducing carbon particles into the reaction chamber.
6 . The method of claim 5 , wherein said introducing carbon particles into the reaction chamber comprises introducing carbon particles having a D50 particle size less than about 100 μm.
7 . The method of claim 1 , further comprising introducing a catalyst material into the intake of the reaction chamber.
8 . The method of claim 7 , wherein said introducing a catalyst material into the intake of the reaction chamber comprises introducing a catalyst material comprising one or more selected from the group consisting of carbon black, activated carbon, Fe 3 O 4 , Fe 2 O 3 , FeO, and CoFeNi oxide into the intake of the reaction chamber.
9 . The method of claim 1 , wherein said introducing the hydrocarbon reactant material into the intake of the plenum comprises introducing natural gas into the intake of the plenum.
10 . The method of claim 1 , wherein said introducing the hydrocarbon reactant material into the intake of the plenum comprises introducing methane gas into the intake of the plenum.
11 . The method of claim 1 , wherein said exposing the aerosol to electromagnetic radiation comprises exposing the aerosol to light having wavelengths within the range of about 8 μm to about 15 μm.
12 . The method of claim 11 , wherein said exposing the aerosol to light having wavelengths within the range of about 8 μm to about 15 μm comprises exposing the aerosol to light having a wavelength of about 10.6 μm.
13 . The method of claim 1 , wherein said exposing is conducted at an absolute pressure in a range of about 0.5 bar to about 1.5 bar.
14 . The method of claim 13 , wherein said exposing is conducted at an absolute pressure of about 1 bar.
15 . The method of claim 1 , further comprising purging at least the reaction chamber and the plenum with nitrogen gas before said introducing the hydrocarbon reactant material into the plenum.
16 . Hydrogen gas produced by a method comprising:
introducing a gaseous hydrocarbon reactant material into an intake of a plenum operatively associated with a reaction chamber, the reaction chamber defining a plurality of apertures therein that are in fluid communication the plenum so that hydrocarbon reactant material in the plenum is introduced into the reaction chamber at multiple locations;
introducing a particulate material into an intake of the reaction chamber, the particulate material mixing with the gaseous hydrocarbon reactant material from the plenum to form an aerosol;
exposing the aerosol to electromagnetic radiation sufficient to raise the temperature of the particulate seed material to a range of about 400° C. to about 1200° C. to pyrolyze the gaseous hydrocarbon reactant material to produce
an aerosol product;
withdrawing the aerosol product via an offtake of the reaction chamber;
recirculating a portion of the withdrawn aerosol product to the intake of the reaction chamber, the recirculated portion of the aerosol product mixing with additional quantities of the gaseous hydrocarbon reactant material from the plenum, the recirculated portion of the aerosol product comprising the particulate material that is introduced into the intake of the reaction chamber;
filtering non-recirculated portions of the aerosol product to produce a filtrate substantially devoid of particulate matter;
separating hydrogen gas from the filtrate; and
diffusing the hydrocarbon reactant material through a porous felt material positioned adjacent the plurality of apertures defined by the reaction chamber.
17 . The method of claim 1 , wherein the plurality of apertures defined by the reaction chamber extend along a length of the reaction chamber and wherein said introducing the hydrocarbon reactant material into the reaction chamber further comprises introducing the hydrocarbon reactant material into the reaction chamber at multiple locations along a length of the reaction chamber.
18 . The method of claim 17 , wherein said introducing the particulate material into the intake of the reaction chamber further comprises introducing the particulate material into an intake located at about a first end of the reaction chamber.
19 . The method of claim 18 , wherein said withdrawing the aerosol product via the offtake of the reaction chamber further comprises withdrawing the aerosol product via an offtake located at about a second end of the reaction chamber.
20 . A method of pyrolyzing a hydrocarbon reactant material to produce hydrogen, comprising:
introducing the hydrocarbon reactant material into a reaction chamber at multiple locations, wherein said introducing comprises diffusing the hydrocarbon reactant material through a porous felt material provided within the reaction chamber;
introducing a particulate material into an intake of the reaction chamber, the particulate material mixing with the hydrocarbon reactant material introduced via the multiple locations to form an aerosol;
exposing the aerosol to electromagnetic radiation sufficient to raise the temperature of the particulate material to a level sufficient to initiate pyrolyzation of the gaseous hydrocarbon reactant material to produce an aerosol product;
withdrawing the aerosol product via an offtake of the reaction chamber;
recirculating a portion of the withdrawn aerosol product to the intake of the reaction chamber, the recirculated portion of the aerosol product mixing with additional quantities of the gaseous hydrocarbon reactant material introduced via the multiple locations, the recirculated portion of the aerosol product comprising the particulate material that is introduced into the intake of the reaction chamber;
filtering non-recirculated portions of the aerosol product to produce a filtrate substantially devoid of particulate matter;
separating a first gas constituent from the filtrate, the first gas constituent comprising hydrogen;
separating a second gas constituent from the filtrate, the second gas constituent comprising unreacted amounts of the gaseous hydrocarbon reactant material; and
recirculating the separated second gas constituent to the reaction chamber so that the separated second gas constituent is introduced into the reaction chamber via the multiple locations.
21 . The method of claim 20 , wherein said introducing the hydrocarbon reactant material into the reaction chamber further comprises introducing the hydrocarbon reactant material into the reaction chamber at multiple locations along a length of the reaction chamber.
22 . The method of claim 21 , wherein said introducing the particulate material into the intake of the reaction chamber further comprises introducing the particulate material into an intake located at about a first end of the reaction chamber.
23 . The method of claim 22 , wherein said withdrawing the aerosol product via the offtake of the reaction chamber further comprises withdrawing the aerosol product via an offtake located at about a second end of the reaction chamber.
24 . Hydrogen gas produced by a method comprising:
introducing a gaseous hydrocarbon reactant material into a reaction chamber at multiple locations, wherein said introducing comprises diffusing the hydrocarbon reactant material through a porous felt material provided within the reaction chamber;
introducing a particulate material into an intake of the reaction chamber, the particulate material mixing with the gaseous hydrocarbon reactant material introduced via the multiple locations to form an aerosol;
exposing the aerosol to electromagnetic radiation sufficient to raise the temperature of the particulate seed material to a range of about 400° C. to about 1200° C. to pyrolyze the gaseous hydrocarbon reactant material to produce an aerosol product;
withdrawing the aerosol product via an offtake of the reaction chamber;
recirculating a portion of the withdrawn aerosol product to the intake of the reaction chamber, the recirculated portion of the aerosol product mixing with additional quantities of the gaseous hydrocarbon reactant material introduced via the multiple locations, the recirculated portion of the aerosol product comprising the particulate material that is introduced into the intake of the reaction chamber;
filtering non-recirculated portions of the aerosol product to produce a filtrate substantially devoid of particulate matter; and
separating hydrogen gas from the filtrate.
25 . The method of claim 24 , wherein said introducing the gaseous hydrocarbon reactant material into the reaction chamber further comprises introducing the gaseous hydrocarbon reactant material into the reaction chamber at multiple locations along a length of the reaction chamber.
26 . The method of claim 25 , wherein said introducing the particulate material into the intake of the reaction chamber further comprises introducing the particulate material into an intake located at about a first end of the reaction chamber.
27 . The method of claim 26 , wherein said withdrawing the aerosol product via the offtake of the reaction chamber further comprises withdrawing the aerosol product via an offtake located at about a second end of the reaction chamber.