US4881476A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Cyclone reactor with internal separation and axial recirculation
Assignee: United States Department of Energy
•
Filing: 1988-07-26
•
Granted: 1989-11-21
•
Expires: 2008-07-26
Abstract
Abstract A cyclone combustor apparatus contains a circular partition plate containing a central circular aperture. The partition plate divides the apparatus into a cylindrical precombustor chamber and a combustor chamber. A coal-water slurry is passed axially into the inlet end of the precombustor chamber, and primary air is passed tangentially into said chamber to establish a cyclonic air flow. Combustion products pass through the partition plate aperture and into the combustor chamber. Secondary air may also be passed tangentially into the combustor chamber adjacent the partition plate to maintain the cyclonic flow. Flue gas is passed axially out of the combustor chamber at the outlet end and ash is withdrawn tangentially from the combuston chamber at the outlet end. A first mixture of flue gas and ash may be tangentially withdrawn from the combustor chamber at the outlet end and recirculated to the axial inlet of the precombustor chamber with the coal-water slurry. A second mixture of flue gas and ash may be tangentially withdrawn from the outlet end of the combustor chamber and passed to a heat exchanger for cooling. Cooled second mixture is then recirculated to the axial inlet of the precombustor chamber. In another embodiment a single cyclone combustor chamber is provided with both the recirculation streams of the first mixture and the second mixture.
Inventors
- 👤 Frederick E. Becker
- 👤 Leo A. Smolensky
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 08:09
CPC Classifications
F; F23; F23C; F23C3/00; F23C3/006; F23C3/008
Claims Analysis
Total Claims: 57
Claim 1
Independent Claim
122 words
A chemical reaction vessel, suitable for use as a combustor for burning fine coal particles, which comprises in combination, a reaction chamber having a circular inlet end wall containing a central circular first fluid inlet opening; a circular discharge end wall containing a central circular first fluid outlet opening; a cylindrical reaction chamber wall therebetween containing a tangential second fluid inlet opening proximate said circular inlet end wall and a tangential second fluid outlet opening proximate said circular discharge end wall; and, a cylindrical inlet chamber contiguous with and attached to said reaction chamber, said inlet chamber having a cylindrical inlet chamber wall attached to said reaction chamber circular inlet end wall coincident with and encompassing said central first fluid inlet opening.
Claim 2
Dependent Claim
122 words
A chemical reaction vessel, suitable for use as a combustor for burning fine coal particles, which comprises in combination, a reaction chamber having a circular inlet end wall containing a central circular first fluid inlet opening; a circular discharge end wall containing a central circular first fluid outlet opening; a cylindrical reaction chamber wall therebetween containing a tangential second fluid inlet opening proximate said circular inlet end wall and a tangential second fluid outlet opening proximate said circular discharge end wall; and, a cylindrical inlet chamber contiguous with and attached to said reaction chamber, said inlet chamber having a cylindrical inlet chamber wall attached to said reaction chamber circular inlet end wall coincident with and encompassing said central first fluid inlet opening.
Claim 3
Dependent Claim
134 words
A chemical reaction vessel suitable for use as a combustor for burning fine coal particles, which comprises in combination, a reaction chamber having a circular inlet end wall containing a central circular first fluid inlet opening; a circular discharge end wall containing a central circular first fluid outlet opening; a cylindrical wall therebetween containing a tangential second fluid inlet opening proximate said circular inlet end wall; and a tangential second fluid outlet opening proximate said circular discharge end wall; and, a tangential third fluid outlet opening in said cylindrical wall proximate said circular discharge end wall, first conduit means providing communications between said third fluid outlet opening and said first fluid inlet opening, and fluid inlet means forming a third fluid inlet opening in said first conduit means proximate said third fluid outlet opening.
Claim 4
Dependent Claim
134 words
A chemical reaction vessel suitable for use as a combustor for burning fine coal particles, which comprises in combination, a reaction chamber having a circular inlet end wall containing a central circular first fluid inlet opening; a circular discharge end wall containing a central circular first fluid outlet opening; a cylindrical wall therebetween containing a tangential second fluid inlet opening proximate said circular inlet end wall; and a tangential second fluid outlet opening proximate said circular discharge end wall; and, a tangential third fluid outlet opening in said cylindrical wall proximate said circular discharge end wall, first conduit means providing communications between said third fluid outlet opening and said first fluid inlet opening, and fluid inlet means forming a third fluid inlet opening in said first conduit means proximate said third fluid outlet opening.
Claim 5
Dependent Claim
68 words
A chemical reaction vessel according to claim 2 including a cylindrical inlet chamber contiguous with and attached to said reaction chamber, said inlet chamber having a cylindrical inlet chamber wall attached to said reaction chamber circular inlet end wall coincident with and encompassing said central first fluid inlet opening, and said inlet chamber cylindrical wall having a tangential fourth fluid inlet opening communicating with said first conduit means.
Claim 6
Dependent Claim
62 words
A chemical reaction vessel according to claim 2 wherein the reaction chamber includes a tangential fourth fluid outlet opening in the reaction chamber cylindrical wall proximate to said reaction chamber discharge end wall, a second conduit means provides means of communication between said fourth fluid outlet opening and said first fluid inlet opening, and said second conduit means includes heat exchanger means.
Claim 7
Dependent Claim
78 words
A chemical reaction vessel according to claim 4 including a cylindrical inlet chamber contiguous with and attached to said reaction chamber, said inlet chamber having a cylindrical inlet chamber wall attached to said reaction chamber inlet end wall coincident with and encompassing said central first fluid inlet, and said inlet chamber wall having a tangential fourth fluid inlet opening communicating with said first conduit means and a tangential fifth fluid inlet opening communicating with said second conduit means.
Claim 8
Dependent Claim
131 words
A chemical reaction vessel suitable for use as a combustor for burning fine coal particles, which comprises in combination, a reaction chamber having a circular inlet end wall containing a central circular first fluid inlet opening; a circular discharge end wall containing a central circular first fluid outlet opening; and a cylindrical wall therebetween containing a tangential second fluid inlet opening proximate said circular inlet end wall, and a tangential second fluid outlet opening proximate said circular discharge end wall; wherein the reaction chamber includes a tangential third fluid outlet opening in the reaction chamber cylindrical wall proximate to said reaction chamber discharge wall, a conduit means provides means of communication between said third fluid outlet opening and said first fluid inlet opening, and said conduit means includes heat exchanger means.
Claim 9
Dependent Claim
131 words
A chemical reaction vessel suitable for use as a combustor for burning fine coal particles, which comprises in combination, a reaction chamber having a circular inlet end wall containing a central circular first fluid inlet opening; a circular discharge end wall containing a central circular first fluid outlet opening; and a cylindrical wall therebetween containing a tangential second fluid inlet opening proximate said circular inlet end wall, and a tangential second fluid outlet opening proximate said circular discharge end wall; wherein the reaction chamber includes a tangential third fluid outlet opening in the reaction chamber cylindrical wall proximate to said reaction chamber discharge wall, a conduit means provides means of communication between said third fluid outlet opening and said first fluid inlet opening, and said conduit means includes heat exchanger means.
Claim 10
Dependent Claim
64 words
A chemical reaction vessel according to claim 6 including a cylindrical inlet chamber contiguous with and attached to said reaction chamber, said inlet chamber having a cylindrical inlet chamber wall attached to said reaction chamber inlet end wall coincident with and encompassing said central first fluid inlet, and said inlet chamber wall having a tangential third fluid inlet opening communicating with said conduit means.
Claim 11
Dependent Claim
141 words
A chemical reaction vessel suitable for use as a combustor for burning fine coal particles, which comprises in combination, a reaction chamber having a circular inlet end wall containing a central circular first fluid inlet opening; a circular discharge end wall containing a central circular first fluid outlet opening; a cylindrical reaction chamber wall therebetween containing a tangential second fluid inlet opening proximate said circular inlet end wall, and a tangential second fluid outlet opening proximate said circular discharge end wall; and, a cylindrical outer shell encompassing said reaction chamber, attached to said reaction chamber inlet end wall and spaced apart from said reaction chamber cylindrical wall to define an annular space, said cylindrical reaction chamber wall having a third fluid inlet opening proximate to said reaction chamber inlet end wall providing communication between said annular space and said reaction chamber.
Claim 12
Dependent Claim
141 words
A chemical reaction vessel suitable for use as a combustor for burning fine coal particles, which comprises in combination, a reaction chamber having a circular inlet end wall containing a central circular first fluid inlet opening; a circular discharge end wall containing a central circular first fluid outlet opening; a cylindrical reaction chamber wall therebetween containing a tangential second fluid inlet opening proximate said circular inlet end wall, and a tangential second fluid outlet opening proximate said circular discharge end wall; and, a cylindrical outer shell encompassing said reaction chamber, attached to said reaction chamber inlet end wall and spaced apart from said reaction chamber cylindrical wall to define an annular space, said cylindrical reaction chamber wall having a third fluid inlet opening proximate to said reaction chamber inlet end wall providing communication between said annular space and said reaction chamber.
Claim 13
Dependent Claim
33 words
A chemical reaction vessel according to claim 8 wherein a plurality of longitudinal vanes are attached to the outer surface of said reaction chamber cylindrical wall and are projected into said annular space.
Claim 14
Dependent Claim
123 words
A chemical reaction vessel, suitable for use as a combustor for burning fine coal particles, which comprises in combination, a reaction chamber having a circular inlet end wall containing a central circular first fluid inlet opening; a circular discharge end wall containing a central circular first fluid outlet opening; a cylindrical reaction chamber wall therebetween containing a tangential second fluid inlet opening proximate said circular inlet end wall, and a tangential second fluid outlet opening proximate said circular discharge end wall; and, a plenum chamber contiguous with and attached to said reaction chamber, having a cylindrical plenum chamber wall encompassing said reaction chamber discharge wall, having a fluid outlet opening in the plenum chamber circular wall, and having a plenum chamber end wall.
Claim 15
Dependent Claim
123 words
A chemical reaction vessel, suitable for use as a combustor for burning fine coal particles, which comprises in combination, a reaction chamber having a circular inlet end wall containing a central circular first fluid inlet opening; a circular discharge end wall containing a central circular first fluid outlet opening; a cylindrical reaction chamber wall therebetween containing a tangential second fluid inlet opening proximate said circular inlet end wall, and a tangential second fluid outlet opening proximate said circular discharge end wall; and, a plenum chamber contiguous with and attached to said reaction chamber, having a cylindrical plenum chamber wall encompassing said reaction chamber discharge wall, having a fluid outlet opening in the plenum chamber circular wall, and having a plenum chamber end wall.
Claim 16
Dependent Claim
151 words
A chemical reaction vessel, suitable for use as a combustor for burning fine coal particles, which comprises in combination: a. A first reaction chamber having an inlet end wall containing a central first fluid inlet opening, a first circular discharge end wall containing a central circular first fluid outlet opening, and a first cylindrical wall therebetween containing a tangential second fluid inlet opening proximate the inlet end wall; b. a second reaction chamber contiguous with said first reaction chamber, having a second cylindrical wall encompassing said first circular discharge end wall, having a tangential third fluid inlet opening in the portion of said second cylindrical wall proximate said first circular discharge end wall, having a circular second discharge end wall containing a central circular second fluid outlet opening, and having a tangential third fluid outlet opening in the portion of said second cylindrical wall proximate to said second discharge end wall.
Claim 17
Dependent Claim
151 words
A chemical reaction vessel, suitable for use as a combustor for burning fine coal particles, which comprises in combination: a. A first reaction chamber having an inlet end wall containing a central first fluid inlet opening, a first circular discharge end wall containing a central circular first fluid outlet opening, and a first cylindrical wall therebetween containing a tangential second fluid inlet opening proximate the inlet end wall; b. a second reaction chamber contiguous with said first reaction chamber, having a second cylindrical wall encompassing said first circular discharge end wall, having a tangential third fluid inlet opening in the portion of said second cylindrical wall proximate said first circular discharge end wall, having a circular second discharge end wall containing a central circular second fluid outlet opening, and having a tangential third fluid outlet opening in the portion of said second cylindrical wall proximate to said second discharge end wall.
Claim 18
Dependent Claim
65 words
A chemical reaction vessel according to claim 11 including a tangential fourth fluid outlet opening in said second cylindrical wall proximate the second circular discharge end wall, first conduit means providing communication between said fourth fluid outlet opening and said first fluid inlet opening, and fluid inlet means forming a fourth fluid inlet opening in said first conduit means proximate said fourth fluid outlet opening.
Claim 19
Dependent Claim
66 words
A chemical reaction vessel according to claim 12 including a cylindrical inlet chamber contiguous with said first reaction chamber, said inlet chamber having a cylindrical inlet chamber wall attached to said first reaction chamber circular inlet end wall coincident with and encompassing said central first fluid inlet opening, and said inlet chamber cylindrical wall having a tangential fifth inlet opening communicating with said first conduit means.
Claim 20
Dependent Claim
67 words
A chemical reaction vessel according to claim 12 wherein the second reaction chamber includes a tangential fifth fluid outlet opening in the portion of the second reaction chamber cylindrical wall proximate said second reaction chamber discharge end wall, a second conduit means provides means of communication between said fifth fluid outlet opening and said first fluid inlet opening, and said second conduit means includes heat exchanger means.
Claim 21
Dependent Claim
77 words
A chemical reaction vessel according to claim 14 including a cylindrical inlet chamber contiguous with said first reaction chamber, said inlet chamber having a cylindrical inlet chamber wall attached to said first reaction chamber inlet end wall coincident with and encompassing said central first fluid inlet, and said inlet chamber wall having a tangential fifth fluid inlet opening communicating with said first conduit means and a tangential sixth fluid inlet opening communicating with said second conduit means.
Claim 22
Dependent Claim
62 words
A chemical reaction vessel according to claim 11 wherein the second reaction chamber includes a tangential fourth fluid outlet opening in the second reaction chamber cylindrical wall proximate said second reaction chamber discharge end wall, a conduit means provides means of communication between said fourth fluid outlet opening and said first fluid inlet opening, and said conduit means includes heat exchanger means.
Claim 23
Dependent Claim
66 words
A chemical reaction vessel according to claim 16 including a cylindrical inlet chamber contiguous with and attached to said first reaction chamber, said inlet chamber having a cylindrical inlet chamber wall attached to said first reaction chamber inlet end wall coincident with and encompassing said central first fluid inlet, and said inlet chamber cylindrical wall having a tangential fourth inlet opening communicating with said conduit means.
Claim 24
Dependent Claim
46 words
A chemical reaction vessel according to claim 11 including a cylindrical outer shell encompassing said first and second reaction chambers attached to said first reaction chamber inlet end wall and spaced apart from said first and second reaction chamber cylindrical walls to define an annular space.
Claim 25
Dependent Claim
36 words
A chemical reaction vessel according to claim 18 wherein a plurality of longitudinal vanes are attached to the outer surface of said first and second reaction chamber cylindrical walls and are projected into said annular space.
Claim 26
Dependent Claim
25 words
A chemical reaction vessel according to claim 18 including an inlet opening in said outer shell proximate to said second reaction chamber circular discharge wall.
Claim 27
Dependent Claim
54 words
A chemical reaction vessel according to claim 11 including a plenum chamber contiguous with and attached to said second reaction chamber, having a cylindrical plenum chamber wall encompassing said second reaction chamber discharge end wall, having a fluid outlet opening in the plenum chamber circular wall, and having a circular plenum chamber end wall.
Claim 28
Dependent Claim
16 words
A chemical reaction vessel according to claim 11 wherein said reaction chambers are in horizontal orientation.
Claim 29
Dependent Claim
16 words
A chemical reaction vessel according to claim 11 wherein said reaction chambers are in vertical orientation.
Claim 30
Dependent Claim
24 words
A chemical reaction vessel according to claim 23 wherein said second reaction chamber is below said first reaction chamber in a downflow process orientation.
Claim 31
Dependent Claim
24 words
A chemical reaction vessel according to claim 25 wherein said second reaction chamber is above said first reaction chamber in an upflow process orientation.
Claim 32
Dependent Claim
228 words
Method of burning a coal-water slurry which comprises the steps of: (a) passing a feed stream containing a coal-water slurry into the inlet end of a cylindrical first combustion chamber having an inlet end wall, a first circular discharge end wall, and a first cylindrical side wall; (b) passing a first combustion air stream tangentially into the inlet end of said cylindrical first combustion chamber under conditions sufficient to maintain a helical flow within said first combustion chamber and propel suspended coal particles centrifically toward the cylindrical side wall of the chamber; (c) withdrawing a combustion product stream comprising steam, combustion gas components, unconsumed air components, uncombusted coal particles, and ash particles axially from the discharge end wall of said first combustion chamber; (d) passing said combustion product stream into the inlet end of a cylindrical second combustion chamber having a second circular discharge end wall and a second cylindrical side wall; (e) passing a second combustion air stream tangentially into the inlet end of said second combustion chamber under conditions sufficient to maintain a helical flow within said second combustion chamber and propel suspended coal and ash particles centrifically toward the second cylindrical side wall of the chamber; (f) withdrawing ash particles tangentially from the discharge end of said second combustion chamber; and, (g) withdrawing flue gas axially from the discharge end of said second combustion chamber.
Claim 33
Dependent Claim
228 words
Method of burning a coal-water slurry which comprises the steps of: (a) passing a feed stream containing a coal-water slurry into the inlet end of a cylindrical first combustion chamber having an inlet end wall, a first circular discharge end wall, and a first cylindrical side wall; (b) passing a first combustion air stream tangentially into the inlet end of said cylindrical first combustion chamber under conditions sufficient to maintain a helical flow within said first combustion chamber and propel suspended coal particles centrifically toward the cylindrical side wall of the chamber; (c) withdrawing a combustion product stream comprising steam, combustion gas components, unconsumed air components, uncombusted coal particles, and ash particles axially from the discharge end wall of said first combustion chamber; (d) passing said combustion product stream into the inlet end of a cylindrical second combustion chamber having a second circular discharge end wall and a second cylindrical side wall; (e) passing a second combustion air stream tangentially into the inlet end of said second combustion chamber under conditions sufficient to maintain a helical flow within said second combustion chamber and propel suspended coal and ash particles centrifically toward the second cylindrical side wall of the chamber; (f) withdrawing ash particles tangentially from the discharge end of said second combustion chamber; and, (g) withdrawing flue gas axially from the discharge end of said second combustion chamber.
Claim 34
Dependent Claim
71 words
Method of claim 26 including the steps of: (h) withdrawing a first mixture stream containing flue gas and ash particles tangentially from the discharge end of said second combustion chamber; (i) passing coal-water slurry into said first mixture stream and thereby producing a second mixture stream; and, (j) passing said second mixture stream into said first cylindrical combustion chamber as at least a portion of the feed stream of step (a).
Claim 35
Dependent Claim
60 words
Method of claim 27 including the steps of withdrawing a third mixture stream containing flue gas and ash particles tangentially from the discharge end of said second combustion chamber, passing said third mixture stream through heat exchanger means, and returning cooled third mixture stream to said first cylindrical combustion chamber as a portion of the feed stream of step (a).
Claim 36
Dependent Claim
19 words
Method of claim 26 wherein said feed stream of step (a) is passed axially into said first combustion chamber.
Claim 37
Dependent Claim
23 words
Method of claim 29 wherein said feed stream of step (a) is passed into said first combustion chamber in a helical flow pattern.
Claim 38
Dependent Claim
23 words
Method of claim 26 wherein said feed stream of step (a) is passed into said first combustion chamber in a helical flow pattern.
Claim 39
Dependent Claim
21 words
Method of claim 26 wherein said combustion product stream is passed axially into the inlet end of said second combustion chamber.
Claim 40
Dependent Claim
21 words
Method of claim 32 wherein said combustion product stream is passed into said second combustion chamber in a helical flow pattern.
Claim 41
Dependent Claim
21 words
Method of claim 26 wherein said combustion product stream is passed into said second combustion chamber in a helical flow pattern.
Claim 42
Dependent Claim
31 words
Method of claim 26 wherein said first combustion air stream is at least partially preheated by passing over at least a portion of the outer surface of said first combustion chamber.
Claim 43
Dependent Claim
33 words
Method of claim 35 wherein said first combustion air stream is at least partially preheated by passing over at least a portion of the outer surface of the first and second combustion chambers.
Claim 44
Dependent Claim
31 words
Method of claim 26 wherein said second combustion air stream is at least partially preheated by passing over at least a portion of the outer surface of said second combustion chamber.
Claim 45
Dependent Claim
47 words
Method of claim 26 wherein said first and second combustion chambers are in a horizontal orientation, said first combustion air stream maintains a horizontal helical flow within the first combustion chamber, and said second combustion air stream maintains a horizontal helical flow within the second combustion chamber.
Claim 46
Dependent Claim
47 words
Method of claim 26 wherein said first and second combustion chambers are in a vertical orientation, said first combustion air stream maintains a downward helical flow within the first combustion chamber, and said second combustion air stream maintains a downward helical flow within the second combustion chamber.
Claim 47
Dependent Claim
47 words
Method of claim 26 wherein said first and second combustion chambers are in a vertical orientation, said first combustion air stream maintains an upward helical flow within the first combustion chamber, and said second combustion air stream maintains an upward helical flow within the second combustion chamber.
Claim 48
Dependent Claim
175 words
Method of burning a coal-water slurry which comprises the steps of: (a) passing a feed stream containing a coal-water slurry into the inlet end of a cylindrical combustion chamber having a circular inlet end wall, a circular discharge end wall, and a cylindrical side wall; (b) passing a combustion air stream tangentially into the inlet end of said cylindrical combustion chamber under conditions sufficient to maintain a helical flow within said combustion chamber and propel suspended coal particles centrifically toward the cylindrical side wall of the chamber; (c) withdrawing ash particles tangentially from the discharge end of said combustion chamber; (d) withdrawing flue gas axially from the discharge end of said combustion chamber; (e) withdrawing a first mixture stream containing flue gas and ash particles tangentially from the discharge end of said second combustion chamber; (f) passing coal-water slurry into said first mixture stream and thereby producing a second mixture stream; and, (g) passing said second mixture stream into said cylindrical combustion chamber as at least a portion of the feed stream of step (a).
Claim 49
Dependent Claim
175 words
Method of burning a coal-water slurry which comprises the steps of: (a) passing a feed stream containing a coal-water slurry into the inlet end of a cylindrical combustion chamber having a circular inlet end wall, a circular discharge end wall, and a cylindrical side wall; (b) passing a combustion air stream tangentially into the inlet end of said cylindrical combustion chamber under conditions sufficient to maintain a helical flow within said combustion chamber and propel suspended coal particles centrifically toward the cylindrical side wall of the chamber; (c) withdrawing ash particles tangentially from the discharge end of said combustion chamber; (d) withdrawing flue gas axially from the discharge end of said combustion chamber; (e) withdrawing a first mixture stream containing flue gas and ash particles tangentially from the discharge end of said second combustion chamber; (f) passing coal-water slurry into said first mixture stream and thereby producing a second mixture stream; and, (g) passing said second mixture stream into said cylindrical combustion chamber as at least a portion of the feed stream of step (a).
Claim 50
Dependent Claim
58 words
Method of claim 41 including the steps of withdrawing a third mixture stream containing flue gas and ash particles tangentially from the discharge end of said combustion chamber, passing said third mixture stream through heat exchanger means, and returning cooled third mixture stream to said cylindrical combustion chamber as a portion of the feed stream of step (a).
Claim 51
Dependent Claim
18 words
Method of claim 41 wherein said feed stream of step (a) is passed axially into said combustion chamber.
Claim 52
Dependent Claim
22 words
Method of claim 43 wherein said feed stream of step (a) is passed into said combustion chamber in a helical flow pattern.
Claim 53
Dependent Claim
22 words
Method of claim 41 wherein said feed stream of step (a) is passed into said combustion chamber in a helical flow pattern.
Claim 54
Dependent Claim
29 words
Method of claim 41 wherein said combustion air stream is at least partially preheated by passing over at least a portion of the outer surface of said combustion chamber.
Claim 55
Dependent Claim
27 words
Method of claim 41 wherein said combustion chamber is in a horizontal orientation, and said combustion air stream maintains a horizontal helical flow within the combustion chamber.
Claim 56
Dependent Claim
27 words
Method of claim 41 wherein said combustion chamber is in a vertical orientation and said combustion air stream maintains a downward helical flow within the combustion chamber.
Claim 57
Dependent Claim
27 words
Method of claim 41 wherein said combustion chamber is in a vertical orientation, and said combustion air stream maintains an upward helical flow within the combustion chamber.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-11-20 | 1993-05-22 | 1993-11-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-11-20 | 1997-05-22 | 1997-11-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-11-20 | 2001-05-22 | 2001-11-21 | $7700.00 | Window Closed / Lapsed |