Pulse generator for treating exhaust gas

• US 6,344,701 B1
• Filed: 08/09/1999
• Issued: 02/05/2002
• Est. Priority Date: 04/04/1996
• Status: Expired due to Fees

• Current Assignee: Mitsubishi Heavy Industries, Ltd.
• Original Assignee: Mitsubishi Heavy Industries, Ltd.
• Inventors: Murata, Masayoshi, Yoshida, Hirohisa, Kawamura, Keisuke, Shigemizu, Tetsuro
• Primary Examiner(s): PALADINI, ALBERT WILLIAM
• Application Number:
  US09/369,842
• Time in Patent Office: 911 Days
• Field of Search: 307/105, 327/264, 327/100, 327/164, 327/172, 327/178, 327/184, 327/291, 333/20
• US Class Current: 307/105
• CPC Class Codes: B01D 2259/818 Employing electrical discharges or the generation of a plasma
• CPC Class Codes: B01D 53/32 by electrical effects other than those provided for in group B01D61/00
• CPC Class Codes: B01J 19/088 giving rise to electric discharges for heating purposes H05B7/00; for the production of ozone C01B13/11, H01T19/00
• CPC Class Codes: B01J 2219/0807 involving electrodes
• CPC Class Codes: B01J 2219/0875 Gas
• CPC Class Codes: B01J 2219/0894 Processes carried out in the presence of a plasma
• CPC Class Codes: F01N 3/0892 Electric or magnetic treatment, e.g. dissociation of noxious components electric filters F01N3/01; regeneration of exhaust filters F01N3/023; heating catalytic converters F01N3/2006

Abstract

An apparatus and method for treating exhaust gases. In this apparatus, a plurality of stages of reactor chambers (R₁, R₂, . . . R_n) are connected in series in the direction of an exhaust gas flow. Further, high-voltage power supplies (V₁, V₂, . . . and V_n) are connected to the reactor chambers (R₁, R₂, . . . and R_n), respectively. Moreover, in each of these reactor chambers, a streamer discharger plasma is generated. Furthermore, the more downstream a reactor chamber of a stage is placed, the lower energy to be cast into the reactor chamber becomes. The density of electrons generated in a gas decomposition unit is high in a portion thereof on the upstream side of the exhaust gas flow and the electron density is low in a portion thereof on the downstream side. Additionally, the present invention further provides a pulse generator in which a high voltage, which is an output voltage of a D.C. charger (V₀), is simultaneously applied to a plurality of distributed constant lines (or transmission lines) (1₋₁, 1₋₂, 2₋₁, 2₋₂, . . . , N₋₁ and N₋₂), which are connected in parallel with one another, by means of a signal shortcircuit switch (S₁).

Claims

1. A pulse generator comprising:

a plurality of stages of a same configuration provided with distributed constant lines having high-voltage-side input terminal portions which are connected in common to a high-voltage-side wiring line connected with a high-voltage-side terminal of a D.C. charger, and further having low-voltage-side input terminal portions which are connected in common to a grounding line serving as a low-voltage-side wiring line connected with a low-voltage-side terminal of said D.C. charger;

low-voltage-side output terminal portions of the adjoining distributed constant lines, which respectively correspond to adjacent upper and lower ones of the stages, being connected in series;

ground lines connecting the input terminal portions of the adjoining distributed constant lines, which respectively correspond to adjacent upper and lower ones of the stages;

a load connected between a low-voltage-side output terminal portion of a top one of said distributed constant lines of a top stage and a low-voltage-side output terminal portion of a bottom one of said distributed constant lines of a bottom stage; and

a shortcircuit switch connected between said high-voltage-side wiring line and said low-voltage-side wiring line.

2. The pulse generator according to claim 1, wherein folded-back parts of core lines of said distributed constant lines respectively serving as component units of each single stage are connected to said high-voltage side wiring line, wherein two outer conductors surrounding remaining parts of said core lines, which are other than the parts connected to said high-voltage side wiring line, through insulating materials are connected to said low-voltage-side wiring line, and wherein input terminal portions of adjacent ones of said outer conductors are shortcircuited by a shortcircuit line.

3. The pulse generator according to claim 1, wherein a first pair of flat plates, each of which has a U-shaped section, in said distributed constant lines respectively serving as component units of each single stage are connected to said low-voltage side wiring line, wherein a second pair of flat plates inserted between said first pair of flat plates, each of which has the U-shaped section, through insulating materials are connected to said low-voltage side wiring line, wherein said first pair of flat plates connected to said low-voltage side wiring line are shortcircuited by a shortcircuit line at input terminal portions thereof, and wherein said second pair of flat plates connected to the high-voltage side wiring line are shortcircuited by a shortcircuit line at output terminal portions thereof.

4. The pulse generator according to claim 1, wherein first and second flat plates, which are provided in such a way as to be parallel to each other, of said distributed constant lines respectively serving as component units of each single stage are connected to said low-voltage side wiring line, wherein a third flat plate inserted between said first and second parallel flat plates in such a way as to be parallel with said first and second parallel flat plates is connected to said high-voltage side wiring line.