Title: Fuel-fired burner with skewed electrode arrangement
Abstract: A fuel-fired burner for use with an emission abatement device comprises a pair of electrodes. Each electrode comprises an arc-contact rod to generate an electrical arc therebetween.
Patent Number: 6,918,755 Issued on 07/19/2005 to Johnson, et al.
| Inventors:
|
Johnson; Randall J. (Greenwood, IN);
Crawley; Wilbur H. (Columbus, IN);
Goldschmidt; Stephen P. (Westport, IN)
|
| Assignee:
|
Arvin Technologies, Inc. (Troy, MI)
|
| Appl. No.:
|
894548 |
| Filed:
|
July 20, 2004 |
| Current U.S. Class: |
431/7; 431/264; 431/285 |
| Intern'l Class: |
F23D 003/40 |
| Field of Search: |
431/7,10,264,284,285,326
123/241
60/275,288
110/165.R
96/69,98
|
References Cited [Referenced By]
U.S. Patent Documents
| 3503348 | Mar., 1970 | Dvirka.
| |
| 3765153 | Oct., 1973 | Grey.
| |
| 3924547 | Dec., 1975 | Werner.
| |
| 3985524 | Oct., 1976 | Masuda.
| |
| 4018577 | Apr., 1977 | Shibuya et al.
| |
| 4084164 | Apr., 1978 | Alt et al.
| |
| 4111636 | Sep., 1978 | Goldberg.
| |
| 4541847 | Sep., 1985 | Oie et al.
| |
| 4549887 | Oct., 1985 | Joannou.
| |
| 4581046 | Apr., 1986 | Bergman.
| |
| 4623365 | Nov., 1986 | Bergman.
| |
| 4652281 | Mar., 1987 | Masuda et al.
| |
| 4654054 | Mar., 1987 | Snaddon et al.
| |
| 4662903 | May., 1987 | Yanagawa.
| |
| 4759778 | Jul., 1988 | Conrad.
| |
| 4828586 | May., 1989 | Joannou.
| |
| 4871495 | Oct., 1989 | Helferich et al.
| |
| 4898105 | Feb., 1990 | Rappoldt et al.
| |
| 4954320 | Sep., 1990 | Birmingham et al.
| |
| 4969328 | Nov., 1990 | Kammel.
| |
| 4976760 | Dec., 1990 | Helferich et al.
| |
| 5009683 | Apr., 1991 | Sun.
| |
| 5022975 | Jun., 1991 | Gordon.
| |
| 5055030 | Oct., 1991 | Schirmer.
| |
| 5059218 | Oct., 1991 | Pick.
| |
| 5097665 | Mar., 1992 | Kammel.
| |
| 5108470 | Apr., 1992 | Pick.
| |
| 5170188 | Dec., 1992 | Bowers et al.
| |
| 5276490 | Jan., 1994 | Bartholmae et al.
| |
| RE34549 | Feb., 1994 | Sun.
| |
| 5322537 | Jun., 1994 | Nakamura et al.
| |
| 5368635 | Nov., 1994 | Yamamoto.
| |
| 5551869 | Sep., 1996 | Brais et al.
| |
| 5555862 | Sep., 1996 | Tozzi.
| |
| 5557923 | Sep., 1996 | Bolt et al.
| |
| 5573577 | Nov., 1996 | Joannou.
| |
| 5582632 | Dec., 1996 | Nohr et al.
| |
| 5593476 | Jan., 1997 | Coppom.
| |
| 5619959 | Apr., 1997 | Tozzi.
| |
| 5647890 | Jul., 1997 | Yamamoto.
| |
| 5702244 | Dec., 1997 | Goodson et al.
| |
| 5758495 | Jun., 1998 | Serra.
| |
| 5807425 | Sep., 1998 | Gibbs.
| |
| 5855653 | Jan., 1999 | Yamamoto.
| |
| 5906677 | May., 1999 | Dudley.
| |
| 6058698 | May., 2000 | Coral et al.
| |
| 6077334 | Jun., 2000 | Joannou.
| |
| 6112519 | Sep., 2000 | Shimasaki et al.
| |
| 6119455 | Sep., 2000 | Hammer et al.
| |
| 6231643 | May., 2001 | Pasic et al.
| |
| 6235090 | May., 2001 | Bernstein et al.
| |
| 6290757 | Sep., 2001 | Lawless.
| |
| 6294004 | Sep., 2001 | Summers et al.
| |
| 6391267 | May., 2002 | Martin et al.
| |
| 6553981 | Apr., 2003 | Suckewer et al.
| |
| 6568362 | May., 2003 | Whealton et al.
| |
| 6572685 | Jun., 2003 | Dunshee.
| |
| 6646377 | Nov., 2003 | Hashimoto.
| |
| 6680037 | Jan., 2004 | Allansson et al.
| |
| 2002/0152890 | Oct., 2002 | Leiser.
| |
| 2002/0185096 | Dec., 2002 | Whealton et al.
| |
| 2003/0037676 | Feb., 2003 | Dunshee.
| |
| 2003/0079609 | May., 2003 | Lobiondo, Jr.
| |
| 2003/0110944 | Jun., 2003 | Wu et al.
| |
| 2003/0164095 | Sep., 2003 | Joannou.
| |
| 2003/0182930 | Oct., 2003 | Goulette et al.
| |
| 2003/0196428 | Oct., 2003 | Iida et al.
| |
| 2003/0233824 | Dec., 2003 | Chun et al.
| |
Primary Examiner: Gravini; Stephen
Attorney, Agent or Firm: Barnes & Thornburg
Claims
1. A fuel-fired burner for use with an emission abatement device, the fuel-fired
burner comprising:
first and second electrodes, each electrode comprising an arc-contact rod, the
arc-contact rods being spaced apart to generate an electrical arc therebetween
and cooperating to define an X-shaped arrangement when viewed in side elevation.
2. The fuel-fired burner of claim 1, wherein the X-shaped arrangement has a crossover
point at which the arc-contact rods cross over one another, and the crossover point
is off center from the center points of the arc-contact rods.
3. The fuel-fired burner of claim 2, comprising an electrode casing surrounding
a portion of each electrode, wherein the crossover point is located farther from
the electrode casings than the center points of the arc-contact rods.
4. The fuel-fired burner of claim 1, wherein the X-shaped arrangement has a crossover
point at which the arc-contact rods cross over one another, and the crossover point
is located at the center points of the arc-contact rods.
5. The fuel-fired burner of claim 1, comprising a fuel nozzle positioned between
the arc-contact rods and a mount plate to which the fuel nozzle and the electrodes
are secured, wherein the X-shaped arrangement has a crossover point at which the
arc-contact rods cross over one another, and, when viewed in side elevation, the
fuel nozzle is positioned between the crossover point and the mount plate.
6. The fuel-fired burner of claim 1, wherein the arc-contact rods define an acute
angle therebetween when viewed in side elevation.
7. The fuel-fired burner of claim 6, comprising an electrode casing surrounding
a portion of each electrode, wherein the X-shaped arrangement has a crossover point
at which the arc-contact rods cross over one another, each arc-contact rod comprises
a proximal portion extending from a respective one of the electrode casings to
the crossover point and a distal portion extending from the crossover point to
a free end of the arc-contact rod, and the acute angle is defined between the distal portions.
8. The fuel-fired burner of claim 1, wherein the arc-contact rods define a right
angle therebetween when viewed in side elevation.
9. A soot abatement device comprising:
a soot trap, and
a fuel-fired burner fluidly coupled to an inlet face of the soot trap, the fuel-fired
burner comprising first and second electrodes, each electrode comprising an arc-contact
rod, the arc-contact rods being spaced apart to generate an electrical arc therebetween
and cooperating to define an X-shaped arrangement when viewed in side elevation.
10. The soot abatement device of claim 9, comprising an electrode casing surrounding
a portion of each electrode, wherein each arc-contact rod comprises a free end
and extends from a respective one of the electrode casings to its free end, the
X-shaped arrangement has a crossover point at which the arc-contact rods cross
over one another, and the crossover point is either located at the center points
of the arc-contact rods or located between the center points of the arc-contact
rods and the free ends of the arc-contact rods in spaced-apart relation to the
center points of the arc-contact rods.
11. The soot abatement device of claim 9, wherein the arc-contact rods define
one of an acute angle and a right angle therebetween when viewed in side elevation.
12. A fuel-fired burner for use with an emission abatement device, the fuel-fired
burner comprising:
first and second electrodes, each electrode comprising a straight arc-contact
rod having a longitudinal axis, the arc-contact rods being spaced apart to generate
an electrical arc therebetween and being non-parallel, the longitudinal axes of
the arc-contact rods being non-intersecting.
13. The fuel-fired burner of claim 12, wherein the arc-contact rods cooperate
to define an electrode gap therebetween, and the size of the electrode gap decreases
and increases as the arc-contact rods extend along their longitudinal axes.
14. The fuel-fired burner of claim 13, comprising an electrode casing surrounding
a portion of each electrode, wherein each arc-contact rod comprises a free end,
and the size of the electrode gap first decreases and then increases as the arc-contact
rods extend from the electrode casings to the free ends.
15. The fuel-fired burner of claim 12, wherein the arc-contact rods cooperate
to define an X-shaped arrangement when viewed in side elevation.
16. The fuel-fired burner of claim 15, wherein the arc-contact rods define an
acute angle therebetween when viewed in side elevation.
17. The fuel-fired burner of claim 15, wherein the arc-contact rods define a
right angle therebetween when viewed in side elevation.
18. The fuel-fired burner of claim 12, wherein the longitudinal axes do not lie
on a common plane.
19. The fuel-fired burner of claim 12, wherein each arc-contact rod is cylindrical.
20. The fuel-fired burner of claim 12, wherein each arc-contact rod is shaped
as a circular cylinder.
Description
FIELD OF THE DISCLOSURE
The present disclosure relates generally to fuel-fired burners for use with emission
abatement devices.
BACKGROUND OF THE DISCLOSURE
Untreated internal combustion engine emissions (e.g., diesel emissions)
include various effluents such as NO
X, hydrocarbons, and carbon monoxide,
for example. Moreover, the untreated emissions from certain types of internal combustion
engines, such as diesel engines, also include particulate carbon-based matter or
"soot". Federal regulations relating to soot emission standards are becoming more
and more rigid thereby furthering the need for devices and/or methods which remove
soot from engine emissions.
The amount of soot released by an engine system can be reduced by the use of
an emission abatement device such as a filter or trap. Such a filter or trap is
periodically regenerated in order to remove the soot therefrom. The filter or trap
may be regenerated by use of a burner to burn the soot trapped in the filter.
SUMMARY
According to an aspect of the present disclosure, there is a fuel-fired
burner for use with an emission abatement device (e.g., a soot abatement device).
The fuel-fired burner comprises first and second electrodes. Each electrode comprises
a straight arc-contact rod having a longitudinal axis. The arc-contact rods are
spaced apart to generate an electrical arc therebetween and are non-parallel. The
longitudinal axes of the arc-contact rods are non-intersecting. As such, the arc-contact
rods are "skewed" relative to one another. In an exemplary embodiment, the arc-contact
rods cooperate to define an X-shaped arrangement when viewed in side elevation.
The above and other features of the present disclosure will become apparent from
the following description and the attached drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
The detailed description particularly refers to the following figures in which:
FIG. 1 is a perspective view of an emission abatement device for reducing emissions
such as soot from exhaust gas discharged from a diesel engine;
FIG. 2 is a bottom view of the emission abatement device;
FIG. 3 is a sectional view taken along lines 3-3 of FIG. 2 showing
a burner fluidly coupled to an inlet face of a soot trap for burning off soot particles
trapped by the soot trap;
FIG. 4 is a side elevation view of an enlarged detail of the burner of FIG.
3 showing a pair of electrodes comprising a pair of arc-contact rods that define
an X-shaped arrangement when viewed in side elevation and that form an acute angle
between one another;
FIG. 5 is a rear elevation view showing an electrode gap between the arc-contact rods;
FIG. 6 is a sectional view taken along lines 6-6 of FIG. 5; and
FIG. 7 is a side elevation view showing the arc-contact rods at right angles
to one another.
DETAILED DESCRIPTION OF THE DRAWINGS
While the concepts of the present disclosure are susceptible to various modifications
and alternative forms, specific exemplary embodiments thereof have been shown by
way of example in the drawings and will herein be described in detail. It should
be understood, however, that there is no intent to limit the disclosure to the
particular forms disclosed, but on the contrary, the intention is to cover all
modifications, equivalents, and alternatives following within the spirit and scope
of the invention as defined by the appended claims.
An emission abatement device
10 for use with an internal combustion engine
12 (i.e., a diesel engine) is provided for treatment of emissions in exhaust
gas discharged from the engine
12, as shown, for example, in FIGS. 1-3.
The emission abatement device
10 is configured, for example, as a soot abatement
device for removing soot from the exhaust gas. The device
10 comprises a
fuel-fired burner
14 and a soot trap
16. The fuel-fired burner
14
is positioned upstream (relative to exhaust gas flow from the engine
12)
from the soot trap
16 so as to be fluidly coupled to an inlet face
18
of the soot trap
16. During operation of the engine
12, exhaust gas
flows through the soot trap
16 thereby trapping soot in the soot trap
16.
Treated exhaust gas may subsequently be released into the atmosphere. From time
to time during operation of the engine
12, the fuel-fired burner
14
is operated to regenerate the soot trap
16 so as to burn off soot trapped
therein. As discussed in more detail herein, an electrode assembly
19 of
the burner
14 is configured to promote efficient combustion of an air-fuel
mixture in the device
10.
Referring to FIG. 3, the burner
14 comprises a burner housing
20.
Exhaust gas discharged from the engine
12 enters the burner housing
20
through an exhaust gas inlet port
22. The exhaust gas that has entered the
burner housing
20 is permitted to flow into a combustion chamber
24
of the burner housing
20 through gas inlet openings
26 defined in
the combustion chamber
24. In such a way, an ignition flame present inside
the combustion chamber
24 is protected from the full engine exhaust gas
flow, while controlled amounts of engine exhaust gas are permitted to enter the
combustion chamber
24 to provide oxygen to facilitate combustion of the
fuel supplied to the burner
14. Exhaust gas not entering the combustion
chamber
24 is directed through a number of openings
28 defined in
a shroud
30 and out an outlet
32 of the burner housing
20.
A flame holder
34 located in the shroud
30 holds the ignition flame
adjacent to the inlet face
18 of the soot trap
16.
The electrode assembly
19 comprises a pair of electrodes
36 and
a pair of electrode casings
38. Each electrode casing
38 surrounds
a portion of a respective one of the electrodes
36 to electrically insulate
that electrode
36 and mount that electrode
36 to a mount plate
40.
When electric power is applied to the electrodes
36, an arc is generated
in an electrode gap
42 between straight arc-contact rods
44 of the
electrodes
36. Fuel supplied by a fuel line
45 enters the fuel-fired
burner
14 through a fuel nozzle
46 and is advanced through the gap
42 between the arc-contact rods
44 thereby causing the fuel to be
ignited by the arc generated by the arc-contact rods
44. It should be appreciated
that the fuel entering the nozzle
46 is generally in the form of a controlled
air/fuel mixture. The arrangement of the arc-contact rods
44 is discussed
in more detail herein.
The fuel-fired burner
14 also comprises a combustion air inlet
48.
During regeneration of the soot trap
16, a flow of pressurized air is introduced
into the burner
14 through the combustion air inlet
48 to provide
oxygen (in addition to oxygen present in the exhaust gas) to sustain combustion
of the fuel.
The soot trap
16 is positioned downstream (relative to exhaust gas flow)
from the burner housing outlet
32. The soot trap
16 includes a filter
substrate
50. The substrate
50 is positioned in a trap housing
52.
The trap housing
52 is secured to the burner housing
20. As such,
gas exiting the burner housing
20 is directed into the trap housing
52
and through the substrate
50. The soot trap
16 may be any type of
commercially available soot trap. For example, the soot trap
16 may be embodied
as any known exhaust soot trap such as a "deep bed" or "wall flow" filter. Deep
bed filters may be embodied as metallic mesh filters, metallic or ceramic foam
filters, ceramic fiber mesh filters, and the like. Wall flow filters, on the other
hand, may be embodied as a cordierite or silicon carbide ceramic filter with alternating
channels plugged at the front and rear of the filter thereby forcing the gas advancing
therethrough into one channel, through the walls, and out another channel. Moreover,
the substrate
50 may be impregnated with a catalytic material such as, for
example, a precious metal catalytic material. The catalytic material may be, for
example, embodied as platinum, rhodium, palladium, including combinations thereof,
along with any other similar catalytic materials. Use of a catalytic material lowers
the temperature needed to ignite trapped soot particles.
The trap housing
52 is secured to a housing
54 of a collector
56.
Specifically, an outlet
58 of the trap housing
52 is secured to an
inlet
60 of the collector housing
54. As such, processed (i.e., filtered)
exhaust gas exiting the substrate
50 (and hence the trap housing
52)
is advanced into the collector
56. The processed exhaust gas is then discharged
from the collector
56 through gas outlet port
60 for eventual release
to atmosphere. It should be appreciated that the gas outlet port
60 may
be coupled to the inlet (or a pipe coupled to the inlet) of a subsequent emission
abatement device (not shown).
The device
10 comprises a number of sensors for use in controlling operation
of the burner
14. For example, the device
10 comprises a flame temperature
sensor
62, a control temperature sensor
64, and an outlet temperature
sensor
66. The temperature sensors
62,
64,
66 are electrically
coupled to an electronic controller (not shown) and, as shown in FIGS. 1 and 2,
may be embodied as thermocouples which extend through the housings of the device
10 although other types of sensors may also be used.
As mentioned in the discussion above, the electrode assembly
19 is arranged
to promote efficient combustion of an air-fuel mixture in the combustion chamber
24. In particular, the arc-contact rods
44 are "skewed" so that the
size of the electrode gap
42 varies along the lengths of the arc-contact
rods
44 to promote stretching or lengthening of the arc generated in the
electrode gap
42 thereby increasing the chances that the arc will encounter
an air-fuel mixture region having an air-to-fuel ratio suitable for ignition. Such
stretching or lengthening of the arc can occur when the arc travels along the arc-contact
rods
44 due to turbulence in the combustion chamber
24.
The arc-contact rods
44 are skewed in the sense that they are spaced apart,
non-parallel, and have non-intersecting longitudinal axes
68. The longitudinal
axes
68 are non-intersecting in the sense that, although they are infinitely
extending imaginary lines, they never intersect (i.e., pass through) one another,
as shown, for example, in FIGS. 5 and 6. As such, the longitudinal axes
68
do not lie on a common plane.
A first example of such a skewed arrangement is shown in FIGS. 3-6 and a second
example of such a skewed arrangement is shown in FIG. 7. In both examples, the
arc-contact rods
44 cooperate to define an X-shaped arrangement when viewed
in side elevation, as shown in FIGS. 3 and 4 with respect to the first example
and as shown in FIG. 7 with respect to the second example. Both X-shaped arrangements
have a crossover point
70 at which the arc-contact rods
44 cross
over one another. In the X-shaped arrangements, the electrode gap
42 decreases
as the arc-contact rods
44 extend from the casings
38 to the crossover
point
70 and increases as the arc-contact rods
44 extend from the
crossover point
70 to free ends
72 of the arc-contact rods.
The crossover point
70 may be located at a variety of locations along
the lengths of the arc-contact rods
44. For example, the crossover point
70 may be located farther from the casings
38 than the center points
of the arc-contact rods
44 (i.e., between the center points of the rods
44 and the free ends
72 thereof) as in the first example of the skewed
arrangement or may be located at the center points of the arc-contact rods
44
as in the second example of the skewed arrangement. Such positioning of the crossover
point
70 promotes generation of the arc between the arc-contact rods
44
rather than between one of the arc-contact rods
44 and structures located
near the casings
38. With respect to the first example of the skewed arrangement,
arc-contact rod distal portions
74 (which extend from the crossover point
70 to the free ends
72) are half the length of arc-contact rod proximal
portions
76 (which extend from the casings
38 to the crossover point
70).
The distal portions
74 of the arc-contact rods
44 form an angle
θ therebetween when viewed in side elevation. The distal portions
74
define an acute angle therebetween in the first example of the skewed arrangement
and define a right angle therebetween in the second example of the skewed arrangement.
The first example allows for more travel of the arc along the arc-contact rods
44 whereas the second example allows for more arc-stretching per unit length
of travel along arc-contact rods
44.
The fuel nozzle
46 is positioned between the arc-contact rods
44.
In particular, when viewed in side elevation as in FIGS. 4 and 7, the fuel nozzle
46 is positioned between the crossover point
70 and the mount plate
40 for flow of fuel through the electrode gap
42 on both sides of
the crossover point
70.
The arc-contact rods
44 are cylindrical to promote generation of the arc
therebetween. In the two illustrated examples, the arc-contact rods
44 are
shaped as a circular cylinder. It is within the scope of this disclosure for the
arc-contact rods
44 to be shaped as a square cylinder, a triangle cylinder,
an elliptical cylinder, and the like.
While the disclosure has been illustrated and described in detail in the drawings
and foregoing description, such an illustration and description is to be considered
as exemplary and not restrictive in character, it being understood that only illustrative
embodiments have been shown and described and that all changes and modifications
that come within the spirit of the disclosure are desired to be protected.
There are a plurality of advantages of the present disclosure arising from
the various features of the apparatus, method, and system described herein. It
will be noted that alternative embodiments of the present disclosure may not include
all of the features described yet still benefit from at least some of the advantages
of such features. Those of ordinary skill in the art may readily devise their own
implementations of an apparatus, method, and system that incorporate one or more
of the features of the present disclosure and fall within the spirit and scope
of the present invention as defined by the appended claims.
*
