MINI-TUBE AIR COOLED INDUSTRIAL STEAM CONDENSER

Abstract

Large scale field erected air cooled industrial steam condenser having 10 heat exchanger bundles per cell arranged in five pairs in a V-shape, each heat exchanger bundle having four primary heat exchangers and four secondary heat exchangers in which each secondary heat exchanger is paired with a single primary heat exchanger. Four primary condensers are arranged such that the tubes are horizontal, while the inlet steam manifolds at one end of the tubes are perpendicular to the primary condenser tubes, i.e., parallel to the transverse axis of the bundle. Steam enters the small inlet steam manifolds from below. Cross-sectional dimensions of the tubes are 200 mm wide with a cross-section height of less than 10 mm with fins that are 10 mm in height, arranged at 9 to 12 fins per inch.

Claims

1. A large scale field erected air cooled industrial steam condenser connected to an industrial steam producing facility, comprising: a plurality of pairs of heat exchanger bundles, each pair of heat exchanger bundles arranged in a V-shape configuration, and each heat exchanger bundle having a longitudinal axis and a transverse axis perpendicular to its longitudinal axis, each heat exchanger bundle comprising a plurality of steam inlet manifolds, a plurality of primary condenser sections, a plurality of outlet condensate headers, and at least one secondary condenser section; each primary condenser comprising a plurality finned tubes each having a longitudinal axis parallel to a corresponding heat exchanger bundle longitudinal axis; each secondary condenser comprising a plurality of finned tubes each having a longitudinal axis parallel to a corresponding heat exchanger transverse axis; each of said steam inlet manifolds having a longitudinal axis parallel to a corresponding heat exchanger transverse axis, each steam inlet manifold configured to receive steam from a steam distribution manifold located below said heat exchange bundles and to distribute steam to a first end of said plurality of finned tubes in a corresponding primary condenser; each of said outlet condensate headers having a longitudinal axis parallel to a corresponding heat exchanger transverse axis and connected on a first side to a second end of said plurality of finned tubes in a corresponding primary condenser to collect condensate, uncondensed steam, and non-condensable gases therefrom, each said outlet condensate header connected on a bottom end to a bottom end of said at least one secondary condenser section, each of said outlet condensate headers also connected at a bottom end to a condensate collection tube, and each said secondary condenser section connected at a top end to a non-condensable collection tube.

2. A large scale field erected air cooled industrial steam condenser according to claim 1, comprising equal numbers of primary and secondary condensers, each second condenser paired with a single primary condenser.

3. A large scale field erected air cooled industrial steam condenser according to claim 2, wherein each heat exchanger bundle comprises four primary condensers and four secondary condensers, wherein the left-to-right orientation of each said primary condenser/secondary condenser pair is reversed relative to an adjacent primary condenser/secondary condenser pair, so that a first two of said steam inlet manifolds in a heat exchanger bundle are directly adjacent to one-another and a second two of said steam inlet manifolds in the same heat exchanger bundle are directly adjacent to one-another.

4. A large scale field erected air cooled industrial steam condenser according to claim 3, wherein bottom ends of said steam inlet manifolds of a first heat exchange bundle are adjacent to bottom ends of steam inlet manifolds in a second heat exchanger bundle in a pair of heat exchange bundles.

5. A large scale field erected air cooled industrial steam condenser according to claim 4, wherein bottom ends of said two adjacent steam inlet manifolds from a first heat exchange bundle and bottom ends of two adjacent steam inlet manifolds from a second heat exchange bundle in a pair of heat exchange bundles are connected to a first end of a one-to-four steam manifold adapter, and wherein a second end of said one-to-four steam manifold adapter is connected to a steam supply manifold.

6. A large scale field erected air cooled industrial steam condenser according to claim 1, wherein said plurality of finned tubes in said primary condensers have a length of 2.0 m to 2.8 m, a cross-sectional width of 200 mm and a cross-sectional height of 4-10 mm.

7. A large scale field erected air cooled industrial steam condenser according to claim 6, wherein said tubes have a cross-sectional height of 5.2-7 mm.

8. A large scale field erected air cooled industrial steam condenser according to claim 7, wherein said tubes have a cross-sectional height of 6.0 mm.

9. A large scale field erected air cooled industrial steam condenser according to claim 1, wherein said plurality of finned tubes in said primary condensers have fins attached to flat sides of said tubes, said fins having a height of 10 mm, and spaced at 9 to 12 fins per inch.

10. A large scale field erected air cooled industrial steam condenser according to claim 1, wherein said plurality of finned tubes in said primary condensers have fins attached to flat sides of said tubes, said fins having a height of 18 mm to 20 mm spanning a space between adjacent tubes and contacting adjacent tubes, said fins spaced at 9 to 12 fins per inch.

11. A large scale field erected air cooled industrial steam condenser according to claim 1, wherein a face area of all secondary condensers in a heat exchange bundle comprises 10-20% of a face area of all primary condensers in a same heat exchange bundle.

12. A large scale field erected air cooled industrial steam condenser according to claim 4, wherein two primary condenser/secondary condenser pairs are adjacent to one-another with the secondary condensers of both pairs adjacent to one-another, said two secondary condensers combined into a single secondary condenser.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0039] FIG. 1A is a perspective view representation of the heat exchange portion of a prior art large scale field erected air cooled industrial steam condenser.

[0040] FIG. 1B is a partially exploded close up view of the heat exchange portion of a prior art large scale field erected air cooled industrial steam condenser, showing the orientation of the tubes relative to the steam distribution manifold.

[0041] FIG. 2A a perspective view representation of the heat exchange portion of a large scale field erected air cooled industrial steam condenser (“ACC”) according to a first embodiment of the invention.

[0042] FIG. 2B is partially exposed close up view of the device shown in FIG. 2A, showing the orientation of the tubes in the primary condenser.

[0043] FIG. 3 a side view representation of the heat exchange portion of an ACC according to a preferred embodiment of the invention.

[0044] FIG. 4 is a close-up side view of the connection between a steam riser and corresponding steam headers at the bottom of the heat exchange portion of an ACC according to an embodiment of the invention.

[0045] FIG. 5 is an end view of the steam riser/transition element/steam manifold assembly for an ACC according to an embodiment of the invention.

[0046] FIG. 6 is a perspective view of cross-section of a prior art ACC tube and fins.

[0047] FIG. 7 is a perspective view of a first embodiment of a mini-tube and fins according to the present invention.

[0048] FIG. 8 is a side view of a large scale field erected air cooled industrial steam condenser according to an embodiment of the invention with V-shaped heat exchange bundle pairs having the primary and secondary condenser arrangement shown in FIG. 2A.

[0049] FIG. 9 is an end view of the large scale field erected air cooled industrial steam condenser shown in FIG. 8.

[0050] FIG. 10 is a top view the large scale field erected air cooled industrial steam condenser shown in FIG. 8.

[0051] FIG. 11 is a perspective view drawing of a primary condenser finned tube bundle according to an embodiment of the invention.

[0052] FIG. 12 is a perspective view photograph of the primary condenser finned tube bundle rendered in the drawing of FIG. 11.

DETAILED DESCRIPTION

[0053] V-Shaped ACC with Horizontal Primary Condensers and Perpendicular Secondary Condensers

[0054] Referring FIGS. 2A, 2B, and 3, bundle pair 2 may be constructed by joining two bundles 4 in a V configuration. Each bundle 4 is constructed of four primary condensers 6 and four secondary condensers 8, each secondary condenser 8 paired with a single primary condenser 6. Tubes 10 in the primary condensers 6 are arranged such that the tubes 10 are horizontal, while the inlet steam manifolds 12 at one end of the tubes are aligned parallel to the transverse axis of the bundle. This arrangement allows the steam to enter the small inlet steam manifolds 12 from below. The tubes 14 in the secondary condenser 8 are likewise aligned parallel to the transverse axis of the bundle. The preferred vertical height of each bundle is 91 inches (2.3 m) to 101 inches (2.57 m) and the preferred bundle length is 38 ft to 45 ft.

[0055] According to a preferred embodiment, measuring along the length of the bundle, each primary condenser 6 accounts for 2.6 m of the length; each steam manifold 12 and condensate outlet header 16 account for 0.3 m of the length, and each secondary bundle 8 accounts for 0.4 m of the length. In any event, each secondary bundle 8 accounts for 10% to 20% of the finned tube face area of the entire heat exchanger bundle.

[0056] Continuing to refer to FIGS. 2A and 3, the preferred heat exchanger bundle according to the invention consists, from one end to the other of the following: secondary condenser 8 with tubes 14 whose longitudinal axes are oriented parallel to the transverse axis of the bundle, followed by an outlet condensate header 16 (approx. 3 inches in size) adjacent to the secondary condenser 8 and communicating steam from a primary condenser 6 directly into the secondary condenser 8, followed by a full size primary condenser 6 with horizontal tubes 10. According to a preferred embodiment, each condensate header 16 has a foot 28 at its bottom that extends beneath and opens into its corresponding secondary condenser 8. The steam inlet manifold 12 (about 0.20 to 0.25 m per side) is at the far end of the first primary condenser 6. The second set of primary and second secondary condensers are mirrored from the first, completing the first half of the heat exchanger. The second half of the heat exchanger mirrors the first half. Adjacent secondary condensers as shown in FIG. 2A and at the center of FIG. 3 may be combined into a single secondary condenser. Condensate collected at the bottom of the condensate headers 16 flows into condensate collection tube 30. Non-condensable gases are drawn from the top of the secondary condensers 8 into non-condensable collection tube 32.

[0057] Bundles are then paired together, preferably in V-frames. This arrangement, as is shown in FIGS. 2A and 3, brings two sets of four steam inlets 18 to two single small areas. These four inlets can be joined to a single steam riser 20 emanating from a large steam duct 22, and connected together via a one to four adapter 24, see FIGS. 4 and 5. No welding of steam manifold across the length of the bundles is required. A-frames may be used, but are less cost effective.

[0058] FIGS. 8-10 show a representative large scale field erected air cooled industrial steam condenser according to an embodiment of the invention with V-shaped heat exchange bundle pairs having the primary and secondary condenser arrangement shown in FIG. 2A. The device shown in FIGS. 8-10 is a 36 cell (6 cell×6 cell) ACC, with the most preferred embodiment of five bundle pairs or “streets” per cell, but the invention may be used with any size ACC, and with any number of bundle pairs or streets per cell.

[0059] Compared to the designs disclosed in U.S. Published Patent Application No. US 2013/0312932, U.S. Published Patent Application No. 2015/0204611, and U.S. Published Patent Application No. 2015/0330709, the above-described embodiment of the present invention increases thermal capacity by 13%.

[0060] Compared to the current standard A-frame technology, the above-described embodiment of the present invention using primary tubes having standard cross-sectional shape and area (200 mm×18.7 mm), see, e.g., FIG. 6 (except for the tube length), increases thermal capacity by 5%, and substantially reduces installed cost by a similar degree.

[0061] According to a most preferred embodiment, the new ACC design described above may be used in conjunction with primary condenser tubes having cross-sectional dimensions of 200 mm wide (air travel length) with a cross-section height (perpendicular to the air travel length) of less than 10 mm, preferably 4-10 mm, more preferably 5.0-9 mm, even more preferably 5.2-7 mm, and most preferably 6.0 mm in height (with 0.8 mm tube thickness and 4.4 mm tube inner diameter), with fins that are 8-12 mm in height, preferably 10 mm in height, arranged at 8-12 fins per inch, preferably 11 fins per inch (FIG. 7). FIGS. 11 and 12 show plurality of primary condenser tubes and fins assembled into a primary condenser bundle according to an embodiment of the invention. According to this preferred embodiment, an additional increase in capacity of 17% is provided, resulting in a combined increase over the prior art A-frame design with standard tubes of 30%, for a single cell at constant fan power.

[0062] According to a further preferred embodiment, actual fins may be 16-22 mm in height, preferably 18.5 mm in height, and span the space between two adjacent tubes, effectively making 8-11 mm of fin available to each tube on each side.

[0063] The description of fin type and dimension above is not intended to limit the invention. The tubes of the invention described herein may be used with fins of any type without departing from the scope of the invention.