U.S. patent application number 17/064929 was filed with the patent office on 2021-12-02 for diesel particulate filtration (dpf) system.
The applicant listed for this patent is South Bank University Enterprises Ltd.. Invention is credited to Arjang Aminishahsavarani, Ali Salimian, Hari Upadhyaya.
Application Number | 20210370275 17/064929 |
Document ID | / |
Family ID | 1000005968599 |
Filed Date | 2021-12-02 |
United States Patent
Application |
20210370275 |
Kind Code |
A9 |
Upadhyaya; Hari ; et
al. |
December 2, 2021 |
Diesel Particulate Filtration (DPF) System
Abstract
A Diesel Particulate Filter (DPF) assembly configured to be
incorporated in the exhaust gas stream, the DPF assembly
comprising: Quartz/Composite ceramic mixture disposed as filter
elements, mechanical support components and optional electrical
soot removal solutions including electrical, di-electrical and
microwave solutions.
Inventors: |
Upadhyaya; Hari; (London,
GB) ; Salimian; Ali; (London, GB) ;
Aminishahsavarani; Arjang; (London, GB) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
South Bank University Enterprises Ltd. |
London |
|
GB |
|
|
Prior
Publication: |
|
Document Identifier |
Publication Date |
|
US 20210106981 A1 |
April 15, 2021 |
|
|
Family ID: |
1000005968599 |
Appl. No.: |
17/064929 |
Filed: |
October 7, 2020 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
62912477 |
Oct 8, 2019 |
|
|
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B01J 23/83 20130101;
B01J 37/08 20130101; B01J 23/10 20130101; B01D 46/0021 20130101;
B01D 2273/22 20130101; B01J 35/04 20130101; F01N 2330/06 20130101;
B01D 2279/30 20130101; B01J 37/0036 20130101; B01D 46/4245
20130101; F01N 3/022 20130101; B01D 39/2068 20130101; B01D 46/16
20130101; B01D 46/0001 20130101; B01D 46/0061 20130101; B01J
37/0215 20130101; B01D 46/0063 20130101; B01D 2239/10 20130101 |
International
Class: |
B01J 23/83 20060101
B01J023/83; B01D 46/00 20060101 B01D046/00; B01D 46/16 20060101
B01D046/16; B01D 39/20 20060101 B01D039/20; B01D 46/42 20060101
B01D046/42; B01J 37/00 20060101 B01J037/00; B01J 37/08 20060101
B01J037/08; B01J 37/02 20060101 B01J037/02; B01J 23/10 20060101
B01J023/10; B01J 35/04 20060101 B01J035/04; F01N 3/022 20060101
F01N003/022 |
Claims
1. A Diesel Particulate Filter (DPF) assembly configured to be
incorporated into the exhaust gas stream of a diesel engine, said
DPF assembly comprising: one or more pneumatically porous ceramic
filter panels; support mechanical components attached to said one
or more panels so as to form a filter core; and a DPF assembly
comprised of one or more housing mechanical components that create
one or more upstream cavities and a downstream cavity pneumatically
connected by said one or more porous ceramic filter panels.
2. the DPF assembly of claim 1 wherein: one or more of said filter
panels has a mechanical support component capable of establishing a
voltage differential across said filter panel, said voltage
differential being large enough to burn off a portion of the soot
capture within said panel.
3. the DPF assembly of claim 2 wherein: one or more of said filter
panels are formed from a filter mix; wherein said filter mix is
comprised of the following percentage (by weight) ranges, with the
total being 100%: 55% to 65% mineral fibers and 35% to 45%
composite powder; with said mineral fibers comprised or one or more
of: Quartz, Alumina; wherein said composite powder is comprised of
the following percentage (by weight) ranges, with the total being
100%: 70% to 80% Silicon Oxide (SiO.sub.2), 4% to 6% Aluminum Oxide
(Al.sub.2O.sub.3), 14% to 18% Diboron Trioxide (B.sub.2O.sub.3) and
2% to 4% Sodium Super Oxide (NaO.sub.2); and said filter mix is
comprised of the following percentage (by weight) ranges, with the
total being 100%: 55% to 65% mineral fibers and 35% to 45%
composite powder.
4. the DPF assembly of claim 3 wherein: one or more said filter
panels has had an electrically conducive electrode applied to all
or part of the upstream and downstream filter fascia surface.
5. the DPF assembly of claim 4 wherein: said electrically
conductive electrode is comprised of one or more of: wires laid
across or metal film deposited across said filter fascia surface;
said composite powder is comprised of the following percentage (by
weight); 75% Silicon Oxide (SiO.sub.2), 5% Aluminum Oxide
(Al.sub.2O.sub.3), 16% Diboron Trioxide (B.sub.2O.sub.3) and 3%
Sodium Super Oxide (NaO.sub.2); and said filter mix is comprised of
the following percentage (by weight): 60% mineral fibers and 40%
composite powder.
6. the DPF assembly of claim 5 wherein: one or more of said panels
have been treated with Ceria (Cerium Dioxide CeO.sub.2).
7. the DPF assembly of claim 1 wherein: one or more of said filter
panels has a mechanical support component capable of establishing a
voltage differential across said filter panel upstream fascia, said
voltage differential being large enough to burn off a portion of
the soot capture within said panel.
8. the DPF assembly of claim 7 wherein: one or more of said filter
panels are formed from a filter mix; wherein said filter mix is
comprised of the following percentage (by weight) ranges, with the
total being 100%: 55% to 65% mineral fibers and 35% to 45%
composite powder; with said mineral fibers comprised or one or more
of: Quartz, Alumina; wherein said composite powder is comprised of
the following percentage (by weight) ranges, with the total being
100%: 70% to 80% Silicon Oxide (SiO.sub.2), 4% to 6% Aluminum Oxide
(Al.sub.2O.sub.3), 14% to 18% Diboron Trioxide (B.sub.2O.sub.3) and
2% to 4% Sodium Super Oxide (NaO.sub.2); and said filter mix is
comprised of the following percentage (by weight) ranges, with the
total being 100%: 55% to 65% mineral fibers and 35% to 45%
composite powder.
9. the DPF assembly of claim 8 wherein: one or more said filter
panels has had an electrically conducive electrode applied to all
or part of the upstream and downstream filter fascia surface.
10. the DPF assembly of claim 9 wherein: said electrically
conductive electrode is comprised of one or more of: wires laid
across or metal film deposited across said filter fascia surface;
said composite powder is comprised of the following percentage (by
weight); 75% Silicon Oxide (SiO.sub.2), 5% Aluminum Oxide
(Al.sub.2O.sub.3), 16% Diboron Trioxide (B.sub.2O.sub.3) and 3%
Sodium Super Oxide (NaO.sub.2); and said filter mix is comprised of
the following percentage (by weight): 60% mineral fibers and 40%
composite powder.
11. the DPF assembly of claim 10 wherein: one or more of said
panels have been treated with Ceria (Cerium Dioxide CeO.sub.2).
12. the DPF assembly of claim 1 wherein: said filter panels are
enclosed within a chamber capable of accepting microwave energy,
said energy being significantly large enough to burn off a portion
of the soot capture within one or more of said panels.
13. the DPF assembly of claim 12 wherein: one or more of said
filter panels are formed from a filter mix; wherein said filter mix
is comprised of the following percentage (by weight) ranges, with
the total being 100%: 55% to 65% mineral fibers and 35% to 45%
composite powder; with said mineral fibers comprised or one or more
of: Quartz, Alumina; wherein said composite powder is comprised of
the following percentage (by weight) ranges, with the total being
100%: 70% to 80% Silicon Oxide (SiO.sub.2), 4% to 6% Aluminum Oxide
(Al.sub.2O.sub.3), 14% to 18% Diboron Trioxide (B.sub.2O.sub.3) and
2% to 4% Sodium Super Oxide (NaO.sub.2); and said filter mix is
comprised of the following percentage (by weight) ranges, with the
total being 100%: 55% to 65% mineral fibers and 35% to 45%
composite powder.
14. the DPF assembly of claim 13 wherein: said composite powder is
comprised of the following percentage (by weight); 75% Silicon
Oxide (SiO.sub.2), 5% Aluminum Oxide (Al.sub.2O.sub.3), 16% Diboron
Trioxide (B.sub.2O.sub.3) and 3% Sodium Super Oxide (NaO.sub.2);
and said filter mix is comprised of the following percentage (by
weight): 60% mineral fibers and 40% composite powder.
15. the DPF assembly of claim 14 wherein: one or more of said
panels have been treated with Ceria (Cerium Dioxide CeO.sub.2).
16. A method for creating filter panels for a Diesel Particulate
Filter (DPF) assembly, said method comprising: crushing mineral
fibers; creating a composite powder comprised of Silicon Oxide
(SiO.sub.2), Aluminum Oxide (Al.sub.2O.sub.3), Diboron Trioxide
(B.sub.2O.sub.3) and Sodium Super Oxide (NaO.sub.2); creating a
filter mix by mixing said mineral fibers with a said composite
powder; placing said mixture in a mold and sintering said mixture
for at least 30 minutes at a temperature of at least 1200.degree.
C.; gradually lowering the mixture temperature to 700.degree. C.
during at least 10 minutes; and allowing the molded product to cool
to ambient temperature.
17. the method claim 16 wherein: said mineral fibers are comprised
or one or more of: Quartz, Alumina.
18. the method of claim 17 wherein: said composite powder is
comprised of the following percentage (by weight) ranges, with the
total being 100%: 70% to 80% Silicon Oxide (SiO.sub.2), 4% to 6%
Aluminum Oxide (Al.sub.2O.sub.3), 14% to 18% Diboron Trioxide
(B.sub.2O.sub.3) and 2% to 4% Sodium Super Oxide (NaO.sub.2); and
said filter mix is comprised of the following percentage (by
weight) ranges, with the total being 100%: 55% to 65% mineral
fibers and 35% to 45% composite powder.
19. the method of claim 18 wherein: said composite powder is
comprised of the following percentage (by weight); 75% Silicon
Oxide (SiO.sub.2), 5% Aluminum Oxide (Al.sub.2O.sub.3), 16% Diboron
Trioxide (B.sub.2O.sub.3) and 3% Sodium Super Oxide (NaO.sub.2);
and said filter mix is comprised of the following percentage (by
weight): 60% mineral fibers and 40% composite powder.
20. the method of claim 19 wherein: said filter panel is removed
from said mold and immersed in a Ceria (Cerium Dioxide CeO.sub.2)
solution for at least 10 minutes; and said ceria treated panel is
sintered at a low temperature for at least 10 minutes.
21. the method of claim 20 wherein: one or more fascia of said
filter panel have a nickel film deposited on their entire
surface.
22. the method of claim 21 wherein: said filter panel is removed
from said mold and immersed in a Ceria (Cerium Dioxide CeO.sub.2)
solution for at least 10 minutes; and said ceria treated panel is
sintered at a low temperature for at least 10 minutes.
23. the method of claim 22 wherein: one or more fascia of said
filter panel have a nickel film deposited on their entire
surface.
24. the method of claim 23 wherein: said composite powder is
comprised of the following percentage (by weight); 75% Silicon
Oxide (SiO.sub.2), 5% Aluminum Oxide (Al.sub.2O.sub.3), 16% Diboron
Trioxide (B.sub.2O.sub.3) and 3% Sodium Super Oxide (NaO.sub.2);
and said filter mix is comprised of the following percentage (by
weight): 60% mineral fibers and 40% composite powder.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to co-pending U.S.
Provisional patent application Ser. No. 62/912,477 titled "Diesel
Particulate filtration (DPF) system", filed on Oct. 8, 2019 the
disclosure of which is herein incorporated by reference in its
entirety.
PATENTS CITED
[0002] The following documents and references are incorporated by
reference in their entirety, Fritz et al (U.S. Pat. Pub. No.
2015/0240681), Sugano (JP2000000339079), Martyniuk (U.S. Pat. No.
4,283,207), Kawamura et al (EP 0682174), Chen et al (U.S. Pat. No.
8,298,311), Fischer et al (U.S. Pat. No. 8,236,084) and Verkiel et
al (U.S. Pat. No. 7,271,801).
FIELD OF THE INVENTION
[0003] The present invention relates to systems and methods for
filtering exhaust gas particulates, and more particularly to
filtering particles upwards from 5 nanometers structures comprised
of composite mixtures including silicon dioxide, aluminum oxide,
boron trioxide and/or sodium oxide forming porous walls that when
exposed to exhaust gases trap harmful elements and then are
optionally disposed of via electrical or electromagnetic means.
DESCRIPTION OF THE RELATED ART
[0004] Driven by the needs of environmental emission reduction
regulations imposed by Euro-VI, and other jurisdictions, Diesel
Particulate Filtration (DPF) devices, systems and methods are
currently essential for all Diesel vehicles in Europe and other
advanced nations. Particulate emissions in exhaust gases from
engines, and particularly from diesel internal combustion engines,
are handled by wall flow honeycombs with low thermal expansion
materials.
[0005] However, the above suffer from the disadvantages of high
cost of production and maintenance, as well as occasional plugs on
the filter material caused by continued operation at low
temperatures. With the transition to hybrids (and designed somewhat
lower operating temperatures). Previous attempts, like US
4,283,207, disclose a diesel engine exhaust particle
filter-incinerator in which conical filter elements are arranged
between an inlet and an outlet. Particulates accumulating on the
filter surfaces are periodically incinerated by a high voltage
applied to electrodes at the edges of the filter surfaces. As is
quickly evident, such an attempt can be particularly
complicated.
[0006] There is a need for improved DPF devices, systems and
methods in order to make diesel engines market competitive over the
coming years.
SUMMARY OF THE INVENTION
[0007] This section is for the purpose of summarizing some aspects
of the present invention and to briefly introduce some embodiments.
Simplifications or omissions may be made to avoid obscuring the
purpose of the section. Such simplifications or omissions are not
intended to limit the scope of the present invention.
[0008] All references, including any patents or patent applications
cited in this specification are hereby incorporated by reference.
No admission is made that any reference constitutes prior art. The
discussion of the references states what their authors assert, and
the applicants reserve the right to challenge the accuracy and
pertinence of the cited documents. It will be clearly understood
that, although a number of prior art publications are referred to
herein, this reference does not constitute an admission that any of
these documents form part of the common general knowledge in the
art.
[0009] It is acknowledged that the term `comprise` may, under
varying jurisdictions, be attributed with either an exclusive or an
inclusive meaning. For the purpose of this specification, and
unless otherwise noted, the term `comprise` shall have an inclusive
meaning--i.e., that it will be taken to mean an inclusion of not
only the listed components it directly references, but also other
non-specified components or elements. This rationale will also be
used when the term `comprised` or `comprising` is used in relation
to one or more steps in a method or process.
[0010] In one aspect, the invention is about a Diesel Particulate
Filter (DPF) assembly configured to be incorporated into the
exhaust gas stream of a diesel engine, said DPF assembly comprising
one or more pneumatically porous ceramic filter panels, support
mechanical components attached to said one or more panels so as to
form a filter core; and a DPF assembly comprised of one or more
housing mechanical components that create one or more upstream
cavities and a downstream cavity pneumatically connected by said
one or more porous ceramic filter panels. In another aspect, one or
more of said filter panels has a mechanical support component
capable of establishing a voltage differential across said filter
panel, said voltage differential being large enough to burn off a
portion of the soot capture within said panel. In yet another
aspect, one or more of said filter panels are formed from a filter
mix, wherein said filter mix is comprised of the following
percentage (by weight) ranges, with the total being 100%, 55% to
65% mineral fibers and 35% to 45% composite powder with said
mineral fibers comprised or one or more of, Quartz, Alumina,
wherein said composite powder is comprised of the following
percentage (by weight) ranges, with the total being 100%, 70% to
80% Silicon Oxide (SiO.sub.2), 4% to 6% Aluminum Oxide
(Al.sub.2O.sub.3), 14% to 18% Diboron Trioxide (B.sub.2O.sub.3) and
2% to 4% Sodium Super Oxide (NaO.sub.2) and said filter mix is
comprised of the following percentage (by weight) ranges, with the
total being 100%: 55% to 65% mineral fibers and 35% to 45%
composite powder.
[0011] In another aspect, one or more said filter panels has had an
electrically conducive electrode applied to all or part of the
upstream and downstream filter fascia surface. In yet another
aspect, said electrically conductive electrode is comprised of one
or more of: wires laid across or metal film deposited across said
filter fascia surface, said composite powder is comprised of the
following percentage (by weight), 75% Silicon Oxide (SiO.sub.2), 5%
Aluminum Oxide (Al.sub.2O.sub.3), 16% Diboron Trioxide
(B.sub.2O.sub.3) and 3% Sodium Super Oxide (NaO.sub.2) and said
filter mix is comprised of the following percentage (by weight):
60% mineral fibers and 40% composite powder. In another aspect, one
or more of said panels have been treated with Ceria (Cerium Dioxide
CeO.sub.2). In yet another aspect, one or more of said filter
panels has a mechanical support component capable of establishing a
voltage differential across said filter panel upstream fascia, said
voltage differential being large enough to burn off a portion of
the soot capture within said panel.
[0012] In another aspect, one or more of said filter panels are
formed from a filter mix, wherein said filter mix is comprised of
the following percentage (by weight) ranges, with the total being
100%, 55% to 65% mineral fibers and 35% to 45% composite powder,
with said mineral fibers comprised or one or more of: Quartz,
Alumina, wherein said composite powder is comprised of the
following percentage (by weight) ranges, with the total being 100%,
70% to 80% Silicon Oxide (SiO.sub.2), 4% to 6% Aluminum Oxide
(Al.sub.2O.sub.3), 14% to 18% Diboron Trioxide (B.sub.2O.sub.3) and
2% to 4% Sodium Super Oxide (NaO.sub.2) and said filter mix is
comprised of the following percentage (by weight) ranges, with the
total being 100%, 55% to 65% mineral fibers and 35% to 45%
composite powder. In yet another aspect, one or more said filter
panels has had an electrically conducive electrode applied to all
or part of the upstream and downstream filter fascia surface. In
yet another aspect, said electrically conductive electrode is
comprised of one or more of: wires laid across or metal film
deposited across said filter fascia surface, said composite powder
is comprised of the following percentage (by weight), 75% Silicon
Oxide (SiO.sub.2), 5% Aluminum Oxide (Al.sub.2O.sub.3), 16% Diboron
Trioxide (B.sub.2O.sub.3) and 3% Sodium Super Oxide (NaO.sub.2) and
said filter mix is comprised of the following percentage (by
weight): 60% mineral fibers and 40% composite powder.
[0013] In another aspect one or more of said panels have been
treated with Ceria (Cerium Dioxide CeO.sub.2). In yet another
aspect, said filter panels are enclosed within a chamber capable of
accepting microwave energy, said energy being significantly large
enough to burn off a portion of the soot capture within one or more
of said panels. In yet another aspect, one or more of said filter
panels are formed from a filter mix, wherein said filter mix is
comprised of the following percentage (by weight) ranges, with the
total being 100%, 55% to 65% mineral fibers and 35% to 45%
composite powder, with said mineral fibers comprised or one or more
of: Quartz, Alumina, wherein said composite powder is comprised of
the following percentage (by weight) ranges, with the total being
100%, 70% to 80% Silicon Oxide (SiO.sub.2), 4% to 6% Aluminum Oxide
(Al.sub.2O.sub.3), 14% to 18% Diboron Trioxide (B.sub.2O.sub.3) and
2% to 4% Sodium Super Oxide (NaO.sub.2) and said filter mix is
comprised of the following percentage (by weight) ranges, with the
total being 100%, 55% to 65% mineral fibers and 35% to 45%
composite powder.
[0014] In another aspect, said composite powder is comprised of the
following percentage (by weight), 75% Silicon Oxide (SiO.sub.2), 5%
Aluminum Oxide (Al.sub.2O.sub.3), 16% Diboron Trioxide
(B.sub.2O.sub.3) and 3% Sodium Super Oxide (NaO.sub.2) and said
filter mix is comprised of the following percentage (by weight):
60% mineral fibers and 40% composite powder. In yet another aspect,
one or more of said panels have been treated with Ceria (Cerium
Dioxide CeO.sub.2). In one aspect, the invention is about a method
for creating filter panels for a Diesel Particulate Filter (DPF)
assembly, said method comprising: crushing mineral fibers, creating
a composite powder comprised of Silicon Oxide (SiO.sub.2), Aluminum
Oxide (Al.sub.2O.sub.3), Diboron Trioxide (B.sub.2O.sub.3) and
Sodium Super Oxide (NaO.sub.2), creating a filter mix by mixing
said mineral fibers with a said composite powder, placing said
mixture in a mold and sintering said mixture for at least 30
minutes at a temperature of at least 1200.degree. C., gradually
lowering the mixture temperature to 700.degree. C. during at least
10 minutes, and allowing the molded product to cool to ambient
temperature. In another aspect, said mineral fibers are comprised
or one or more of: Quartz, Alumina.
[0015] In another aspect, said composite powder is comprised of the
following percentage (by weight) ranges, with the total being 100%:
70% to 80% Silicon Oxide (SiO.sub.2), 4% to 6% Aluminum Oxide
(Al.sub.2O.sub.3), 14% to 18% Diboron Trioxide (B.sub.2O.sub.3) and
2% to 4% Sodium Super Oxide (NaO.sub.2), and said filter mix is
comprised of the following percentage (by weight) ranges, with the
total being 100%: 55% to 65% mineral fibers and 35% to 45%
composite powder. In yet another aspect, said composite powder is
comprised of the following percentage (by weight), 75% Silicon
Oxide (SiO.sub.2), 5% Aluminum Oxide (Al.sub.2O.sub.3), 16% Diboron
Trioxide (B.sub.2O.sub.3) and 3% Sodium Super Oxide (NaO.sub.2),
and said filter mix is comprised of the following percentage (by
weight): 60% mineral fibers and 40% composite powder. In yet
another aspect, said filter panel is removed from said mold and
immersed in a Ceria (Cerium Dioxide CeO.sub.2) solution for at
least 10 minutes and said ceria treated panel is sintered at a low
temperature for at least 10 minutes.
[0016] In another aspect, one or more fascia of said filter panel
have a nickel film deposited on their entire surface. In yet
another aspect, said filter panel is removed from said mold and
immersed in a Ceria (Cerium Dioxide CeO.sub.2) solution for at
least 10 minutes; and said ceria treated panel is sintered at a low
temperature for at least 10 minutes. In another aspect, one or more
fascia of said filter panel have a nickel film deposited on their
entire surface. In yet another aspect, said composite powder is
comprised of the following percentage (by weight), 75% Silicon
Oxide (SiO.sub.2), 5% Aluminum Oxide (Al.sub.2O.sub.3), 16% Diboron
Trioxide (B.sub.2O.sub.3) and 3% Sodium Super Oxide (NaO.sub.2) and
said filter mix is comprised of the following percentage (by
weight): 60% mineral fibers and 40% composite powder.
[0017] Other features and advantages of the present invention will
become apparent upon examining the following detailed description
of an embodiment thereof, taken in conjunction with the attached
drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] FIG. 1 is a perspective view of a cutaway showing the
proposed configuration of a Diesel Particulate Filter (DPF),
according to an exemplary embodiment of the invention.
[0019] FIG. 2 is another perspective view of a cutaway showing the
proposed configuration of a Diesel Particulate Filter (DPF),
according to an exemplary embodiment of the invention.
[0020] FIGS. 3-4 show scanning electron microscope images of the
proposed mineral based filtering material, according to an
exemplary embodiment of the invention.
[0021] FIG. 5 is a perspective view of a DPF assembled from filter
wafers within the metallic support, according to an exemplary
embodiment of the invention.
[0022] FIG. 6 is a front perspective view of the shroud with
internal channel showing the proposed configuration of a DPF,
according to an exemplary embodiment of the invention.
[0023] FIG. 7 is a back-perspective view of the shroud with
internal channel showing the proposed configuration of a DPF,
according to an exemplary embodiment of the invention.
[0024] FIG. 8 shows a perspective view of the various components of
the DPF before final assembly, according to an exemplary embodiment
of the invention.
[0025] FIG. 9 is a perspective view of the DPF housing the filter
components, according to an exemplary embodiment of the
invention.
[0026] FIG. 10 is a perspective view of the complete DPF, according
to an exemplary embodiment of the invention.
[0027] FIG. 11 is a perspective view of a DPF assembled from filter
wafers with the metallic inserts over the filter fascia, according
to an exemplary embodiment of the invention.
[0028] The above-described and other features will be appreciated
and understood by those skilled in the art from the following
detailed description, drawings, and appended claims.
DETAILED DESCRIPTION OF THE INVENTION
[0029] This section is for the purpose of summarizing some aspects
of the present invention and to briefly introduce some embodiments.
Simplifications or omissions may be made to avoid obscuring the
purpose of the section. Such simplifications or omissions are not
intended to limit the scope of the present invention.
[0030] To provide an overall understanding of the invention,
certain illustrative embodiments and examples will now be
described. However, it will be understood by one of ordinary skill
in the art that the same or equivalent functions and sequences may
be accomplished by different embodiments that are also intended to
be encompassed within the spirit and scope of the disclosure. The
compositions, apparatuses, systems and/or methods described herein
may be adapted and modified as is appropriate for the application
being addressed and that those described herein may be employed in
other suitable applications, and that such other additions and
modifications will not depart from the scope hereof.
[0031] Simplifications or omissions may be made to avoid obscuring
the purpose of the section. Such simplifications or omissions are
not intended to limit the scope of the present invention. All
references, including any patents or patent applications cited in
this specification are hereby incorporated by reference. No
admission is made that any reference constitutes prior art. The
discussion of the references states what their authors assert, and
the applicants reserve the right to challenge the accuracy and
pertinence of the cited documents. It will be clearly understood
that, although a number of prior art publications are referred to
herein, this reference does not constitute an admission that any of
these documents form part of the common general knowledge in the
art.
[0032] As used in the specification and claims, the singular forms
"a", "an" and "the" include plural references unless the context
clearly dictates otherwise. For example, the term "a transaction"
may include a plurality of transaction unless the context clearly
dictates otherwise. As used in the specification and claims,
singular names or types referenced include variations within the
family of said name unless the context clearly dictates
otherwise.
[0033] Certain terminology is used in the following description for
convenience only and is not limiting. The words "lower," "upper,"
"bottom," "top," "front," "back," "left," "right" and "sides"
designate directions in the drawings to which reference is made,
but are not limiting with respect to the orientation in which the
modules or any assembly of them may be used.
[0034] It is acknowledged that the term `comprise` may, under
varying jurisdictions, be attributed with either an exclusive or an
inclusive meaning. For the purpose of this specification, and
unless otherwise noted, the term `comprise` shall have an inclusive
meaning--i.e. that it will be taken to mean an inclusion of not
only the listed components it directly references, but also other
non-specified components or elements. This rationale will also be
used when the term `comprised` or `comprising` is used in relation
to one or more steps in a method or process.
[0035] A Diesel Particulate Filter (DPF) is normally placed within
the exhaust stream coming out of the internal combustion diesel
engine, in a position which maximizes the amount of filter material
surface to which the exhaust stream is exposed, so as to
efficiently capture the particulates.
[0036] In one embodiment (FIGS. 1-2), the particle filter 100 is
comprised an inlet cap 102 with an inlet aperture 104 for receiving
exhaust gases from an engine, in particular a diesel engine. A
cylindrical outside shell or casing 108 mechanically supports an
inlet filter unit 106 of annular or cone shape. The cap 102 support
116 comprises one or more structural frame members interconnecting
the casing 108 and the filter 106, in one embodiment, the curved
surface of the filter 106 cone 110 extends and connects into the
cap 102.
[0037] The filter 106 plates are made of a pneumatically porous
composite material (discussed further below), which capture the
soot and other such particulates along the conical surface of the
filter 106. At the end of the filter unit 106 opposite cap 102
there is provided an outlet filter unit support 112. Said outlet
support 112 has one or more outlet apertures 114 for connection to
an exhaust passage to the atmosphere, possibly via other
pollution-removing components. The bottom of the filter 106 is
pneumatically sealed to the casing 108 forcing the air to go
through the filter 106 material on its way to the exhaust.
[0038] The entire filter unit is located in a generally cylindrical
casing 108 which extends between cap 102 and support 112. Note the
shape need not be `just` cylindrical, as long as the clearance
between In one embodiment, the casing is sealed to cap and support
so that a gas-tight passage is provided there between Cap 102, cone
106, casing 108 and support 116 are of materials that may be a
combination of metal and ceramic or other electronically
non-conductive materials. The supports 116 hold cone 106 plates
spaced from the casing 108.
[0039] In one embodiment, during use, exhaust gases passing through
the filter 100 enter at the aperture 104 are pneumatically directed
around the cone shaped filtering component 106. The gases then pass
radially inwardly through the filter material, with the filtered
gases then going into the central passageway and thence exit
outwards through the back-support plate aperture. As exhaust gases
pass through the unit, carbon in the form of soot particles
accumulate on the upstream fascia of the cone 106.
[0040] In one embodiment, the filter plates 502 or other suitable
shaped (e.g. cone 106) filtering material is formed from a filter
mix comprised of a mixture of mineral fibers and a composite powder
mix. The mineral fiber mix is comprised of all or parts of quartz,
alumina or other suitable similar structural materials. When using
quartz, the quartz is comprised of crushed quartz fibers that are
crushed by spinning at 30,000 rpm.
[0041] The composite powder mix is comprised of a mixture Silicon
Oxide (SiO.sub.2), Aluminum Oxide (Al.sub.2O.sub.3), Diboron
Trioxide (B.sub.2O.sub.3) and Sodium Super Oxide (NaO.sub.2) plus
other suitable similar materials. While variation of up to 20% per
material per weight appear to be suitable, in one embodiment, the
composite powder mix is comprised of a mixture (by weight) of about
seventy-five percent (75%) of Silicon Oxide (SiO.sub.2), Six
percent (6%) of Aluminum Oxide (Al.sub.2O.sub.3), Sixteen percent
(16%) of Diboron Trioxide (B.sub.2O.sub.3) and three percent (3%)
of Sodium Super Oxide (NaO.sub.2).
[0042] The overall filter is then shaped from a filter mix material
mix comprised of (by weight) 60% mineral fiber mix and 40% of a
composite powder, with a 20% variation possible with similar
results.
[0043] The resultant pneumatically porous material may be
shaped/formed into plates, squares or other suitable shapes. The
shown cone shape 106, is but one possible shape, including other
embodiments (plates, portions of a circle, etc., which will be
shown below) all using the same filtering material.
[0044] The mixture is then placed inside a crucible or a high
temperature mold defining the desired filter shape. The assembly is
then placed inside a furnace and sintered at a temperature of
1200-1250.degree. C. for about forty minutes. The temperature of
the furnace is then gradually lowered over a period of about twenty
minutes to a temperature of 700.degree. C. and the assembly is then
taken out of the furnace and the plate is demolded.
[0045] The resulting material is pneumatically porous, and its
porosity value is determined by controlling the mass per volume
ratio of the quartz/powder mixture when it is molded. An electron
microscope image of the filter material (FIGS. 3-4) shows pores 302
extending through the structure 304. These are due to the
advantageous use of the crushed quartz fiber pieces in the original
mixture which form an internal scaffold or framework for the
composite material.
[0046] In one embodiment, the surface of the one or more filter
plates 502 or cones 106 is further treated by immersion in a
solution of Ceria (Cerium Dioxide CeO.sub.2) and a solvent, so that
the Ceria may be absorbed and lines the pores 302 within the plate
502 material. Ceria serves as a catalyst for the combustion of the
soot particles. In one embodiment, the solution with the Ceria is a
50:50 mixture of Ethanol and Water. While ethanol was used, any
other suitable organic solvents (e.g. Methanol, Hexane, etc.) may
be used. Immersion for 10 or more minutes is enough, with an hour
preferred, to attach the Ceria to the pores of the filter.
[0047] The immersion is followed by low-temperature sintering at
between 400-700 deg. C, which stabilizes the Ceria. By stabilizing
the Ceria within the network of internal surfaces of the pores 302
of the plate material, the Ceria is well-adapted to efficiently
interact with the soot particles.
[0048] The incorporation of Ceria as a catalyst material for the
combustion process has the advantage of allowing operation of the
filter unit at a lower temperature than a unit with the composite
material alone. By stabilizing the Ceria on the internal pore
surfaces of the composite material, it can efficiently interact
with the soot particles without suffering any degradation by the
flow of exhaust gases. The Ceria material produces an improved
discharge path through the plates and hence, facilitates the
discharge assisted regeneration within the filter. Ceria has the
advantages of performance efficiency, ease of application, thermal
stability and being unaffected by the sulfur content of the exhaust
gases. In an alternate embodiment, platinum may be used instead of
Ceria.
[0049] The above described material (whether treated with Ceria or
not) in operation will capture the soot particles within the pores
302 and burn the soot when a sufficient temperature is reached by
the filter plate/cone 106. It is relatively simple to modify the
above filter for use with a wide range of engines. As one example,
for a typical 320cc diesel engine, the filter of FIGS. 1-2 has a
length of 10 cm and a diameter of 4 cm. These dimensions can be
changed for engines of different sizes. The porosity of the filter
and in particular of the plates can be controlled by adjusting the
mass per volume ratio of the mixture which is molded to form the
plates/cone of the filter.
[0050] The above-described arrangement has numerous advantages. It
permits the continuous filtration and combustion of soot particles
independently of the engine's operating conduction. It minimizes
the fuel consumption associated with the active regeneration
process. It is simple and cheap to manufacture. It permits the
elimination of platinum catalyst loading and has a good
adaptability to diesel fuel with a high sulfur content.
[0051] The porous material used for the plates permits a good flow
through of exhaust gases together with providing an effective
substrate for the capture of soot. It has the advantage that its
porosity is adjustable. Parameters which can be controlled to
affect this are composition of the ceramic, fiber size
distribution, ceramic to fiber ratio, heating profile (temperature,
time, heat up and cool down rates), and the fibers mass per volume
in the mixture. Furthermore, the material can withstand the
corrosive environment and is stable up to 1250.degree. C. It can be
molded into various shapes.
[0052] In one embodiment, in operation, the unit core 500 (FIGS.
5-7) may be configured as a series of filter plates 502 formed into
thin slats that are held by one or more columns 504. The columns
504 may be metal (both ferrous and non-ferrous), carbon composite
or any other suitable structural material mounted on a support base
508.
[0053] The filter core is then 500 is housed within an assembly 600
comprised of a cylindrical housing 602 and a front nosecone 604.
Unlike FIGS. 1-2, the nosecone 604 and housing 602 are not
pneumatically porous, for the intent is for the exhaust gases to
enter the assembly 600 through one or more scoops, duct or inlets
608. Note that the nosecone and housing may be made of ferrous or
non-ferrous metals, as well as of other materials such as carbon
composites, ceramics, etc., with the limitation that they are best
when comprised of pneumatically non-porous materials, so that the
majority (preferably totality) of the exhaust gases flow through
the core 500.
[0054] The above, force the exhaust gases into the interior of the
assembly 600, where since the support plate 508 spans the diameter
of the housing 602, they can only get through by passing from the
upstream cavity 702 to the downstream 704 cavity. FIGS. 8-10 shows
the assembly 600 mounted on the plate 508 (minus the cylindrical
housing 602), with the downstream cavity 704 connected to the
exhaust duct 802. FIG. 10 shows the complete assembly 1000,
including the intake duct 1002.
[0055] In one embodiment, the unit operates with the assembly 1000
downstream from the engine exhaust. As the engine operates, the
exhaust gases go through the filter material, and the soot
accumulates on the upstream cavity 702 fascia of the filter plates
502, creating a pressure differential between the upstream cavity
702 and the downstream cavity 704. In a first embodiment, similar
to that of disposable oil filters, the soot simply accumulates, and
the complete filter assembly 500 or module 600 is replaced and
disposed of either at a number of miles, or when the pressure
differential exceeds a threshold over time.
[0056] In another embodiment, the heat brought by the exhaust gases
raises the temperature of the filter plates 502, and the soot is
burned off. Similarly, either at a regular interval and/or when the
pressure differential is sensed to be above a threshold, the
columns 504 may be artificially heated (either via built in
resistors and/or convective transmission within metal to the
columns from outside the module 600, say by heating the exhaust
pipe or duct 802), which will result in the plates 502 heating
enough to burn off the soot on the upstream cavity 702 fascia,
clearing the pores 302 and resulting in improved gas flow.
[0057] In one embodiment, the carbon nature of the soot is used as
a cleaning agent and electrical conductor across the plates 502.
The columns 504 are made of non-conductive material such as ceramic
where a high DC or AC potential may be applied across the plate 502
by means of porous electrodes such as a metallic net. When clean,
no current would flow across the quartz/composite powder plate 502,
however, the effective dielectric of the quartz/composite powder
plate 502 varies as soot accumulates on the composite And
eventually it reaches a point that triggers the discharge. The
discharge stops once the soot is illuminated and filter is
clean.
[0058] When sufficient soot particles have collected to form a soot
cake within the fascia and body of a plate 502, the electrical
transmissivity of the soot will reach a point where the soot
`completes the circuit`, and a spark discharge occurs. The
discharge passes through the soot cake and creates a localized
temperature rise within the collected soot cake which burns it off.
The discharge then stops until enough soot particles have again
collected.
[0059] The above may be constantly charged (no sensing required),
or be charged every so many starts of the engine, or miles driven,
or refueling, or hours of operation, allowing for the regular
cleaning of the filter plates 502 without additional
pressure/condition sensors. The above collection of soot particles
in the form of soot cake, and hence the sparks discharges to remove
the soot, both occur throughout the entire thickness of the plates.
Since the electrodes extend over the entire major surfaces of the
plates, soot particles are effectively removed from the entire
volume of the plates.
[0060] In one embodiment, the plates are provided on their upstream
cavity 702 radially outer faces 506 with electrodes 1102/1104 (FIG.
11) of a first polarity and on the downstream cavity 704 inner
faces 510 with electrodes of a second polarity. In one embodiment
these electrodes are comprised of one or more electrically
transmissive wires applied to the surface of the filter faces
506/510 or may be placed on the same faces 506/510 but formed of
thin metal films deposited on the entire respective surfaces
506/510 of the filter plate 502 faces. The metal films may be
Nickel or any other suitable ferrous or non-ferrous metal
deposited.
[0061] In one embodiment, the voltage is applied across the plate
(from the front fascia 506 to the back 510), so that if the
electrodes are connected to corresponding electrical terminals, and
an AC or DC voltage applied, when there is enough soot material
(carbon based) to complete the electrical path, the electrical
discharge will burn off the soot. Depending on the orientation of
the unit 1000, any soot ashes will collect either at the bottom of
the unit or at the bottom of the case 602. When AC voltages are
used, it may be possible to vary the frequency of the voltage
depending on the material composition of the soot, so as to clean
the plate 502 more efficiently.
[0062] The AC or DC potential may be applied continuously so that
the occurrences of spark discharges are determined solely by the
buildup of soot cake. Alternatively, the voltage may be pulsed, so
that it is applied simultaneously to all plates 502 or sequentially
to each individual plate 502. In another embodiment, the, the
voltage may be applied intermittently at predetermined intervals.
If the difference in pressure between the upstream 702 and
downstream 704 portions is measure, the voltage may be applied once
a certain threshold of pressure is reached.
CONCLUSION
[0063] In concluding the detailed description, it should be noted
that it would be obvious to those skilled in the art that many
variations and modifications can be made to the shown embodiments
without substantially departing from the principles of the present
invention. Also, such variations and modifications are intended to
be included herein within the scope of the present invention as set
forth in the appended claims. Further, in the claims hereafter, the
structures, materials, acts and equivalents of all means or
step-plus function elements are intended to include any structure,
materials or acts for performing their cited functions.
[0064] It should be emphasized that the above-described embodiments
of the present invention, particularly any "exemplary embodiments"
are merely possible examples of the implementations, merely set
forth for a clear understanding of the principles of the invention.
Any variations and modifications may be made to the above-described
embodiments of the invention without departing substantially from
the spirit of the principles of the invention. All such
modifications and variations are intended to be included herein
within the scope of the disclosure and present invention and
protected by the following claims.
[0065] The present invention has been described in sufficient
detail with a certain degree of particularity. The utilities
thereof are appreciated by those skilled in the art. It is
understood to those skilled in the art that the present disclosure
of embodiments has been made by way of examples only and that
numerous changes in the arrangement and combination of parts may be
resorted without departing from the spirit and scope of the
invention as claimed. Accordingly, the scope of the present
invention is defined by the appended claims rather than the
foregoing description of embodiments.
* * * * *