Systems for pyrolyzing methane
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 . Apparatus for pyrolyzing a gaseous hydrocarbon reactant material to produce hydrogen gas, comprising:
a reactor, said reactor including:
a reaction chamber having an intake and an offtake, the reaction chamber also defining a plurality of apertures therein;
a porous felt material positioned within the reaction chamber at a position adjacent the plurality of apertures;
a plenum having an intake configured to receive the gaseous hydrocarbon material, the plenum being in fluid communication with the plurality of apertures so that gaseous hydrocarbon reactant material within the plenum flows into the reaction chamber via the plurality of apertures and the porous felt material;
a window, the window allowing electromagnetic radiation to enter the reaction chamber;
a light source operatively associated with the window of said reactor, said light source directing electromagnetic radiation into the reaction chamber through said window;
a first recirculation conduit operatively connected between the offtake of the reaction chamber and the intake of the reaction chamber, said first recirculation conduit recirculating 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, said filter receiving un-recirculated amounts of the aerosol product from the reaction chamber, said filter producing a filtrate and a retentate, the retentate comprising particulate matter removed from the aerosol product;
a first gas separator operatively associated with said filter, said first gas separator separating a first gas constituent from the filtrate, the first gas constituent comprising hydrogen;
a second gas separator operatively associated with said first gas separator, said second gas separator separating a second gas constituent from the filtrate, the second gas constituent comprising unreacted amounts of the gaseous hydrocarbon reactant material; and
a second recirculation conduit operatively connected between said second gas separator and the intake of the plenum of said reactor, said second recirculation conduit recirculating to the intake of the plenum the second gas constituent removed by said second gas separator.
2 . The apparatus of claim 1 , further comprising a heat exchanger operatively connected between said filter and said first gas separator, said heat exchanger cooling the filtrate from said filter before the filtrate enters said first gas separator.
3 . The apparatus of claim 2 , further comprising a second filter operatively associated with said heat exchanger, said second filter removing additional amounts of particulate matter retained in the filtrate before the filtrate is directed to said first gas separator.
4 . The apparatus of claim 3 , further comprising a second heat exchanger operatively connected between said heat exchanger and said second filter.
5 . The apparatus of claim 1 , wherein said first gas separator comprises a gas permeable membrane and wherein the first gas constituent comprises a permeate of the gas permeable membrane of said first gas separator.
6 . The apparatus of claim 1 , wherein said first gas separator comprises a gas permeable membrane and wherein the first gas constituent comprises a retentate of the gas permeable membrane of said first gas separator.
7 . The apparatus of claim 1 , wherein said second gas separator comprises a gas permeable membrane and wherein the second gas constituent comprises a permeate of the gas permeable membrane of said second gas separator.
8 . The apparatus of claim 1 , wherein said second gas separator comprises a gas permeable membrane and wherein the second gas constituent comprises a retentate of the gas permeable membrane of said second gas separator.
9 . The apparatus of claim 1 , wherein the intake of the reaction chamber is configured to receive a particulate seed material and introduce defined quantities of the particulate seed material into the reaction chamber of said reactor.
10 . The apparatus of claim 9 , wherein the intake of the reaction chamber is configured to receive a catalyst material and introduce defined quantities of the catalyst material into the reaction chamber of said reactor.
11 . The apparatus of claim 1 , further comprising a turbulence inducer operatively associated with the intake of the reaction chamber.
12 . The apparatus of claim 1 , further comprising a screen positioned between the porous felt material and an interior region of the reaction chamber.
13 . The apparatus of claim 1 , further comprising a screen positioned within the porous felt material.
14 . The apparatus of claim 1 , wherein the porous felt material comprises a refractory material.
15 . The apparatus of claim 14 , wherein the refractory porous felt material comprises carbon.
16 . The apparatus of claim 1 , wherein the plurality of apertures defined by the reaction chamber are sized and spaced to achieve a desired distribution of the hydrocarbon material along a length of the reaction chamber.
17 . The apparatus of claim 16 , wherein some of the plurality of apertures comprise circularly-shaped apertures and wherein others of the plurality of apertures comprise oval-shaped apertures.
18 . The apparatus of claim 1 , wherein said light source produces electromagnetic radiation having wavelengths in a range of about 8 μm to about 15 μm.
19 . The apparatus of claim 18 , wherein said light source comprises a laser.
20 . The apparatus of claim 19 , wherein said laser comprises a CO 2 laser.
21 . The apparatus of claim 1 , further comprising a supply of nitrogen gas operatively connected to said reactor.
22 . A reactor, comprising:
a housing comprising a first end, a second end, and a side wall connecting the first and second ends so that a reaction chamber is defined therebetween, at least a portion of the side wall of said housing defining a plurality of apertures therein, said housing also defining an intake and an offtake;
a porous felt material provided within said housing at a position adjacent the plurality of apertures;
a plenum surrounding at least the portion of the side wall defining the plurality of apertures, said plenum having an intake, said plenum being substantially closed to the side wall of said housing so that an internal region defined by said plenum and the side wall of said housing is in fluid communication with the reaction chamber via the plurality of apertures and the porous felt material; and
a window mounted within the first end of said reaction chamber, said window being substantially gas-tight and substantially transparent to electromagnetic radiation in at least an infrared wavelength range so that infrared electromagnetic radiation passing through said window enters the reaction chamber defined by said housing of said reactor.
23 . The reactor of claim 22 , wherein the porous felt material comprises carbon.
24 . The reactor of claim 22 , further comprising a screen positioned adjacent the porous felt material and the reaction chamber defined by said housing.
25 . The reactor of claim 22 further comprising a screen positioned within the porous felt material.
26 . The reactor of claim 22 , wherein said housing comprises an elongate cylindrically-shaped member and wherein the plurality of apertures defined by the side wall of said housing comprises a plurality of holes that extend substantially around the entirety of a circumference of the side wall and extend along a length of the side wall for a distance that is less than a distance separating the first and second ends of said housing, and wherein said plenum comprises a generally cylindrically-shaped member that surrounds the side wall of said housing and encloses the plurality of holes in the side wall of said housing so that the internal region defined by said plenum is in fluid communication with the reaction chamber via the plurality of holes in the side wall of said housing and the porous felt material.