Modular plasma reformer treatment system

Abstract

A modular plasma treatment system has interchangeable and easily accessible inner and outer electrodes that concentrically nest within an outer housing of one or more plasma reformers. The inner and outer electrodes have self-centering features that allow for blind-fitting of the interchangeable inner and outer electrodes during electrode replacement and maintenance. A plurality of reformers that generate different types of plasmas are preferably arranged serially to allow for a mixture of separate plasmas within the same reaction area and to increase utilization of short-lived radicals.

What is claimed is: 
     
       1. A modular plasma treatment system, comprising:
 a first outer housing of a first plasma reformer having a first exhaust inlet for receiving a first input gaseous stream and a first exhaust outlet for expelling a first output gaseous stream, wherein the first outer housing comprises a first housing inner receiving chamber;   a first outer electrode sized and dimensioned to abut first housing portions of the first housing inner receiving chamber such that the first outer electrode does not substantially move when set in place within the first housing inner receiving chamber, wherein the first outer electrode comprises a first electrode inner receiving chamber;   a second outer electrode sized and dimensioned to abut the first housing portions of the first housing inner receiving chamber such that the second outer electrode does not substantially move when set in place within the first housing inner receiving chamber, wherein the second outer electrode comprises a second electrode inner receiving chamber;   a first inner electrode sized and dimensioned to abut first electrode portions of the first electrode inner receiving chamber such that the first inner electrode does not substantially move when set in place within the first electrode inner receiving chamber; and   a second inner electrode sized and dimensioned to abut second electrode portions of the second electrode inner receiving chamber such that the second inner electrode does not substantially move when set in place within the second electrode inner receiving chamber.   
     
     
       2. The modular plasma treatment system of  claim 1 , wherein the first housing inner receiving chamber and a first exterior portion of the first outer electrode comprise self-centering features that center the first outer electrode with respect to the first outer housing as the first outer electrode is set in place within the first housing inner receiving chamber. 
     
     
       3. The modular plasma treatment system of  claim 2 , wherein the self-centering features comprise a tapered wall of the first housing inner receiving chamber that centers the first and second outer electrodes when either is set in place within the first housing inner receiving chamber. 
     
     
       4. The modular plasma treatment system of  claim 2 , wherein the self-centering features comprise a tapered exterior cross-section of the first outer electrode that widens against the first housing portions of the first housing inner receiving chamber as the first outer electrode is set in place within the first housing inner receiving chamber. 
     
     
       5. The modular plasma treatment system of  claim 1 , wherein the first electrode inner receiving chamber and a first exterior portion of the first inner electrode comprise self-centering features that center the first inner electrode with respect to the first inner electrode inner receiving chamber as the first inner electrode is set in place within the first inner electrode inner receiving chamber. 
     
     
       6. The modular plasma treatment system of  claim 5 , wherein the self-centering features comprise a tapered wall of the first electrode inner receiving chamber that centers the first inner electrode when the first inner electrode is set in place within the first electrode inner receiving chamber. 
     
     
       7. The modular plasma treatment system of  claim 5 , wherein the self-centering features comprise a tapered exterior cross-section of the first inner electrode that widens against the first electrode portions of the first electrode inner receiving chamber as the first inner electrode is set in place within the first electrode inner receiving chamber. 
     
     
       8. The modular plasma treatment system of  claim 1 , wherein the first outer electrode and the first inner electrode, when set in place within the first housing inner receiving chamber, are configured to provide a first plasma gap for a first plasma and wherein the second outer electrode and the second inner electrode, when set in place within the first housing inner receiving chamber, are configured to provide a second plasma gap for a second plasma different from the first plasma. 
     
     
       9. The modular plasma treatment system of  claim 1 , wherein the first plasma reformer comprises a dielectric barrier discharge plasma reformer to generate a dielectric barrier discharge plasma. 
     
     
       10. The modular plasma treatment system of  claim 9 , wherein the first outer electrode comprises interior conductive formertions to generate electric field gradients between points of the conductive projections. 
     
     
       11. The modular plasma treatment system of  claim 10 , wherein the interior conductive projections comprise conductive screw tips screwed into holes of the first outer electrode. 
     
     
       12. The modular plasma treatment system of  claim 10 , wherein at least two of the interior conductive projections comprise different dimensions from one another to provide different electric field gradients to precipitate particulate matter having different properties. 
     
     
       13. The modular plasma treatment system of  claim 9 , wherein the first exhaust inlet comprises surface features that alter air pressure within an excitation chamber of the first plasma reformer to direct the first input gaseous stream in a cyclone motion to points of highest energy density inside the excitation chamber. 
     
     
       14. The modular plasma treatment system of  claim 13 ,
 wherein the first plasma reformer comprises a rotating glide arc reformer and the second plasma reformer comprises a DBD plasma reformer,   at least one of the first outer electrode and the first inner electrode rotate a textured surface to direct the first input gaseous stream in a cyclone motion to points of highest energy density inside an excitation chamber of the rotating glide arc reformer.   
     
     
       15. The modular plasma treatment system of  claim 14 , further comprising coaxial electrodes that discharge into each of the glide-arc plasma and the DBD plasma. 
     
     
       16. The modular plasma treatment system of  claim 1 , further comprising:
 a second outer housing of a second plasma reformer having a second exhaust inlet for receiving a second input gaseous stream and a second exhaust outlet for expelling a second output gaseous stream, wherein the second outer housing comprises a second housing inner receiving chamber;   a third outer electrode sized and dimensioned to abut second housing portions of the second housing inner receiving chamber such that the third outer electrode does not substantially move when set in place within the second housing inner receiving chamber, wherein the third outer electrode comprises a third electrode inner receiving chamber;   a fourth outer electrode sized and dimensioned to abut the second housing portions of the second housing inner receiving chamber such that the fourth outer electrode does not substantially move when set in place within the second housing inner receiving chamber, wherein the fourth outer electrode comprises a fourth electrode inner receiving chamber;   a third inner electrode sized and dimensioned to abut third electrode portions of the third electrode inner receiving chamber such that the third inner electrode does not substantially move when set in place within the third electrode inner receiving chamber; and   a fourth inner electrode sized and dimensioned to abut fourth electrode portions of the fourth electrode inner receiving chamber such that the fourth inner electrode does not substantially move when set in place within the fourth electrode inner receiving chamber,
 wherein the first output gaseous stream feeds the second input gaseous stream. 
   
     
     
       17. The modular plasma treatment system of  claim 16 , wherein the rotating glide arc reformer generates a glide-arc plasma and the DBD plasma reformer generates a DBD plasma. 
     
     
       18. The modular plasma treatment system of  claim 17 , further comprising a magnetic field generator that generates a magnetic field around the co-axial electrodes. 
     
     
       19. The modular plasma treatment system of  claim 18 , wherein the first outer housing of the first plasma reformer is disposed above a particulate filter expelling the first output gaseous stream to transfer waste heat from the first output gaseous stream to an oxidant conduit. 
     
     
       20. The modular plasma treatment system of  claim 19 , wherein the air source comprises at least one of a blower and an on-board turbocharger. 
     
     
       21. The modular plasma treatment system of  claim 1 , wherein the plasma treatment system oxidizes particulate matter in a reaction zone between the first inner electrode and the first outer electrode. 
     
     
       22. The modular plasma treatment system of  claim 21 , wherein the air dryer uses a desiccant to remove water vapor from the intake air. 
     
     
       23. The modular plasma treatment system of  claim 1 , further comprising an air drier that receives intake air from an air source and outputs dried air, wherein the first exhaust inlet receives the dried air and outputs oxidants to the first output gaseous stream. 
     
     
       24. The modular plasma treatment system of  claim 1 , further comprising a voltage transformer integrated with a feedthrough of the first plasma reformer to deliver power from the voltage power transformer to the first outer electrode and the first inner electrode. 
     
     
       25. The modular plasma treatment system of  claim 1 , further comprising a fuel injector that injects fuel into the first input gaseous stream. 
     
     
       26. The modular plasma treatment system of  claim 25 , wherein the first plasma reformer comprises at least one of a DBD reformer and a rotating glide-arc reformer. 
     
     
       27. The modular plasma treatment system of  claim 1 , further comprising a microwave generator that generates microwaves directed towards the first outer housing. 
     
     
       28. A method of treating a gas stream, the method comprising:
 directing the gas stream into a first reaction zone;   energizing the gas stream to generate a first plasma comprising a dielectric barrier discharge (DBD) plasma between a first inner electrode nested within a second electrode in the first reaction zone;   further energizing, within a second reaction zone, the gas stream energized in the first reaction zone to generate a second plasma comprising one of a rotating glide-arc plasma or a microwave plasma,   wherein the first and second reaction zones are disposed serially such that the first inner electrode is directly coupled to a common reaction zone common to the first and second reaction zones and configured to sustain therein the first plasma.    
     
     
       29. The method of  claim 28 , wherein the gas stream comprises a hydrocarbon.  
     
     
       30. The method of  claim 28 , wherein the gas stream is treated to produce hydrogen.  
     
     
       31. The method of  claim 28 , wherein the first inner electrode contacts the second plasma in the common reaction zone.  
     
     
       32. The method of  claim 28 , wherein the first reaction zone is in linear sequence to the second reaction zone.  
     
     
       33. The method of  claim 28 , wherein a dielectric layer is disposed between the first inner electrode and the second electrode.  
     
     
       34. The method of  claim 28 , wherein the rotating glide-arc plasma is generated in the second reaction zone.  
     
     
       35. The method of  claim 34 , wherein the rotating glide-arc plasma is formed between a third electrode nested within a fourth electrode, and wherein a gap between the third and fourth electrode increases along an axis of the third electrode.  
     
     
       36. The method of  claim 28 , wherein the DBD plasma is generated in linear sequence to the second plasma.  
     
     
       37. The method of  claim 28 , further comprising generating a low pressure zone within the first reaction zone.  
     
     
       38. The method of  claim 37 , wherein the low pressure zone is downstream of the gas stream energized in the first reaction zone.  
     
     
       39. The method of  claim 37 , wherein the low pressure zone is downstream of the DBD plasma.  
     
     
       40. The method of  claim 28 , further comprising an electric field gradient overlapping the first reaction zone, and wherein the second plasma is the microwave plasma.  
     
     
       41. The method of  claim 28 , further comprising directing the gas stream into a third reaction zone comprising a third plasma.  
     
     
       42. The method of  claim 28 , wherein the first inner electrode is arranged co-axially with the second electrode.  
     
     
       43. The method of  claim 42 , wherein a third plasma is formed by a third electrode arranged co-axially with a fourth electrode.  
     
     
       44. A method of generating a product from a gas stream, comprising:
 energizing the gas stream in a first reaction zone, wherein the first reaction zone comprises a dielectric barrier discharge (DBD) plasma;   directing the energized gas stream into a second reaction zone, and further energizing the energized gas stream in the second reaction zone to generate therein a glide-arc plasma;
 wherein a first inner electrode of the first reaction zone is directly coupled to a common reaction zone common to the first and second reaction zones and configured to sustain therein the glide-arc plasma; and 
   directing an exhaust comprising the product out of one of the first or the second reaction zones.    
     
     
       45. The method of  claim 44 , wherein the product is hydrogen and the gas stream comprises a hydrocarbon.  
     
     
       46. The method of  claim 44 , wherein the DBD plasma is formed between the first inner electrode coaxial with a second electrode, wherein a dielectric layer is disposed between the first inner electrode and the second electrode.  
     
     
       47. The method of  claim 44 , wherein the second reaction zone is downstream of the first reaction zone.  
     
     
       48. The method of  claim 47 , wherein the glide-arc plasma is formed between a third electrode coaxial with a fourth electrode, wherein a gap between the third electrode and the fourth electrode increases along an axis of the third electrode.  
     
     
       49. The method of  claim 44 , further comprising generating a third plasma different than the second plasma, wherein the third plasma is downstream from the second reaction zone.  
     
     
       50. A method of generating a product from a gas stream, comprising:
 energizing the gas stream in a first reaction zone;   directing the energized gas stream into a second reaction zone, and further energizing the energized gas stream to generate a second plasma;
 wherein one of the first reaction zone or the second reaction zone comprises a glide-arc plasma, 
 wherein a first inner electrode of the first reaction zone is directly coupled to a common reaction zone common to the first and second reaction zones and configured to sustain therein the glide-arc plasma, and 
   wherein the gas stream is energized in the first reaction zone by the first inner electrode nested within a second electrode; and   directing an exhaust comprising the product out of one of the first or the second reaction zones.    
     
     
       51. A plasma device, comprising:
 a first reaction zone configured to energize a gas stream using a first electrode co-axial with a second electrode;   a second reaction zone configured to generate a plasma using a third electrode co-axial with a fourth electrode, wherein a gap between the third and fourth electrodes increases along an axis of the third electrode;   wherein the first electrode is directly coupled to a common reaction zone common to the first and second reaction zones and configured to sustain therein the plasma; and   a microwave generator directed toward the second reaction zone.    
     
     
       52. The plasma device of  claim 51 , wherein the first electrode is upstream of the third electrode.  
     
     
       53. The plasma device of  claim 51 , wherein the first electrode comprises a dielectric layer on a surface facing the second electrode.  
     
     
       54. The plasma device of  claim 51 , wherein the second reaction zone is downstream of the first reaction zone.  
     
     
       55. A method of treating a gas stream, the method comprising:
 directing the gas stream into a first reaction zone;   generating, within the first reaction zone, an energized gas stream;   directing the energized gas stream toward a plasma in a second reaction zone, wherein a first electrode of the first reaction zone is directly coupled to a common reaction zone common to the first and second reaction zones and configured to sustain therein the plasma, and wherein a gap between the first electrode and a second electrode in the first reaction zone increases along an axis of the first electrode;   directing a microwave at the second reaction zone; and   reforming the gas stream in the second reaction zone to form a product.    
     
     
       56. The method of  claim 55 , wherein the microwave is directed toward an inlet of the second reaction zone.  
     
     
       57. The method of  claim 55 , wherein the microwave is directed toward an outlet of the second reaction zone.  
     
     
       58. The method of  claim 55 , wherein the microwave is directed toward the first and second reaction zones.  
     
     
       59. The method of  claim 55 , further comprising using a waveguide to direct the microwave at one of the first reaction zone, an inlet of the first reaction zone, an outlet of the first reaction zone, the energized gas stream, or the plasma.