JP7019612B2 - All secondary air-cooled industrial steam condenser - Google Patents

Description

The present invention relates to a large-scale on-site assembly type air-cooled industrial steam condenser.

Current finned tubes used in most large on-site assembly air-cooled industrial steam condensers (“ACC”) are approximately 11 meters long x 200 mm wide (also known as “air transfer length”). Use a flat tube with semi-circular front and trailing edges and an internal height of 18.8 mm (perpendicular to the air transfer length). The thickness of the tube wall is 1.35 mm. The fins are brazed to the flat sides on either side of each tube. The fins are typically 18.5 mm high with 11 fins per inch (25.4 mm) apart. The fin surface has a wavy pattern to promote heat transfer and support fin stiffness. The standard spacing between the centers of the tubes is 57.2 mm. The tube itself constitutes about one-third of the cross-section face area (perpendicular to the air flow direction), while the fins make up approximately two-thirds of the cross-section face area. Occupy. There is a small space of 1.5 mm between the tips of adjacent fins. Under summer ambient conditions, the maximum steam velocity through the tube can be typically as high as 28 mps and more typically 23-25 mps. A single A-shaped frame design combining these tubes and fins has been optimized based on tube length, fin spacing, fin height and shape, and air transfer length. Finned tubes are typically assembled into a heat exchanger tube bundle of 39 tubes per heat exchanger tube bundle, with 10-14 tube bundles per fan arranged together in a single A-shaped frame. It is placed in two heat exchangers. The fan is typically located at the bottom of the A-shaped frame and forcibly ventilates air upwards through the bundle of tubes. The overall design of the tube and fins, as well as the air pressure drop due to the tube and fin combination, also fits into the air movement capacity of large caliber (36 feet (10.9 meters)) fans operating at 200-250 horsepower. It has been optimized. This optimized placement has not changed much across many different manufacturers since the concept of single-row elliptic tubes was introduced more than 20 years ago.

The typical A-shaped frame ACC described above includes both a first stage or "primary" condenser tube bundle and a second stage or "secondary" tube bundle. About 80% to 90% of the heat exchanger tube bundles are first stage or primary condenser tube bundles. Steam enters the top of the primary condenser tube bundle, and the condenser and some steam are ejected from the bottom. The first stage configuration has good thermal efficiency, but does not provide a means to remove the non-condensable gas. To clear the non-condensable gas passing through the first stage tube bundle, 10% to 20% of the heat exchanger tube bundle is configured as a second stage or secondary tube bundle, typically interspersed between the primary tube bundles. , Suction the vapor from the lower condensate manifold. In this arrangement, vapors and non-condensable gases travel through the first stage tube bundle as they are drawn into the bottom of the secondary tube bundle. As the gas mixture rises through the secondary tube bundle, the remaining vapor condenses, concentrating the non-condensable gas. The top of the secondary tube bundle is attached to a vacuum manifold that removes non-condensable gas from the system.

Modifications of the standard prior art to the ACC arrangement are disclosed, for example, in US Patent Application Publication Nos. 2015/0204611 and 2015/0330709. These specifications show the same finned tube, but with a significantly shorter tube length, placed in a series of smaller A-shaped frames, typically 5 A-shaped frames per fan. Has been done. Part of this logic is to reduce the vapor pressure drop, which has a small effect on total capacity in summer but a greater effect in winter conditions. Another part of this logic is to weld the top steam manifold ducts to each of the tube bundles in the factory and ship them together, eliminating the expensive field welding work. The net effect of this arrangement with steam manifolds installed factory-installed and shipped with tube bundles is to reduce the length of the tubes to fit the manifolds in standard high cube shipping containers. In summer conditions, the comparative capacity for a standard single A-frame design with similar overall dimensions is reduced by about 3% because the tubes are shorter and therefore the total surface area is reduced.

The inventions presented herein are 1) novel tube designs for use in heat exchanger systems, including but not limited to large on-site assembly industrial steam condensers, and 2) power plants. Including new designs for large on-site assembly industrial steam condensers for, etc., both significantly increase the heat capacity of the ACC, while reducing materials in some configurations. Various aspects and / or embodiments of the present invention are shown below.

According to various embodiments of the pipe design invention, the pipe is 2.044 m in length, the cross-sectional dimensions of the pipe are 100-200 mm wide, preferably 125 mm wide (air transfer length), and the cross-sectional height (air movement length). The height (perpendicular to the air movement length) is less than 10 mm, preferably 4 to 10 mm, more preferably 5.0 to 9 mm, even more preferably 5.2 to 7 mm, most preferably 6.0 mm (“outer tube width”). The number of fins per inch (25.4 mm) is 9 to 12, preferably 9.8. According to a more preferred embodiment, the actual fins are 17-20 mm in height, preferably 18.5 mm in height, straddling the space between two adjacent tubes and effectively 9.25 mm. Make the fins available on each side for each tube.

Manufacturing pipes with smaller cross sections (same air movement length, but significantly smaller in height) is as much as possible to accommodate the enormous amount of steam output by large power plants. It is directly contrary to the current predominant view in the art that pipes need to be manufactured in large cross sections and the larger the size of the pipe, the lower the cost. The cost of this arrangement is much higher than the prior art tube arrangement, but we unexpectedly find that the increased efficiency of using lower height tubes (in the most preferred embodiment, of the prior art). It is more than 30% more efficient than pipes), and we have found that it does more than offset the cost increase. This novel pipe design may be used in prior art large-scale on-site assembly industrial steam condensers (eg, as described in the Background Techniques section), or as described herein below. It may be used in conjunction with the ACC design.

Next, a new design of a large-scale on-site assembly type industrial steam condenser will be examined. The main feature of the present invention is that all the ACC tube bundles according to the present invention are constructed as secondary tube bundles. Inside, steam is fed from the bottom to upwardly oriented tubes (aligned parallel to the transverse axis of the tube bundle, with each tube generally oriented 25 ° to 35 °, preferably vertical to 30 °). Condensate is recovered from the bottom of the tube bundle, preferably using an integrated / hybrid manifold that both delivers steam to the tube and recovers the condensate from the tube. According to one embodiment, the integrated / hybrid manifold prevents the condensate from descending the steam delivery riser (s) and is instead delivered to the condensate recovery pipe connected to the integrated / hybrid manifold. It may be constructed as follows. According to an alternative embodiment, the condensate may be constructed so that the condensate can descend the steam delivery riser and is removed from the steam delivery duct closer to the ground. The top of the tube is connected to a separate manifold for recovering non-condensable gas. This new "all secondary" ACC configuration is an A-shaped frame with two secondary tube bundles joined at the top with a single manifold that collects non-condensable gas from the tube, or It may be configured with two non-condensable manifolds, one at the top of each tube bundle.

As used herein, the terms "all secondary" and "no primary" mean that all tube bundles receive steam from the bottom, condensate at the bottom, and non-condensable gas from the top. Refers to a large-scale on-site assembly type air-cooled industrial steam condenser to be delivered. By comparison, the primary tube bundle in a large on-site assembly air-cooled industrial steam condenser receives steam at the top, delivers condenser at the bottom, and delivers non-condensable gas to a separate secondary condenser at the bottom. do.

However, preferably, the ACC of the present invention may be arranged in a V-shape, in which two bundles of secondary dedicated capacitors are connected at the bottom to a single integrated steam distribution manifold / condensate recovery manifold and are separate. It has a non-condensate condensate recovery manifold at the top of each tube bundle.

According to a preferred V-shaped configuration embodiment, the steam manifold resides at the bottom of the tube bundle, so entering the manifold in more than one position reduces the size of the manifold and allows the finned tube to be slightly longer. .. Tubes of smaller cross section described herein (200 mm x height less than 10 mm, preferably 4-10 mm, more preferably 5.0-9 mm, even more preferably 5.2-7 mm, most preferably 6.0 mm. ), The system shows at least 25% to 30% improved performance over the standard ACC placement and configuration described above, and the unit can be reduced by a similar amount in terms of floor space. There is.

According to a further alternative embodiment, the novel ACC design of the present invention has dimensions of 100 mm ×, preferably 4-10 mm, more preferably 5.0-9 mm, even more preferably 5.2-7 mm. Most preferably, it may be used with an offset fin, along with a pipe having a height of 6.0 mm.

According to a further embodiment, the novel ACC design of the invention has 120 mm or up to 200 mm x 5 mm-7 mm with "arrowhead" type fins with 9.8 fins per inch (25.4 mm). May be used in the tube.

According to yet another embodiment, the novel ACC design of the invention may be used with a tube having "louver" fins that behave much like offset fins, making it more readily available and easier to manufacture. Become.

According to preferred and most preferred embodiments of the invention combining the most preferred ACC configuration with the most preferred tube dimensions, the ACC of the invention has the following features and dimensions:
No primary tube bundle, all secondary tube bundles (all tubes receive steam from the bottom, condensate through the bottom, and non-condensable gas from the top to the outside),
Outer diameter 4-10 mm (preferably 5-7 mm, most preferably 6.0 mm) x 100-200 mm (most preferably) of a tube of 4, 5 (most preferred) or 6 V-shaped tube bundles per cell / fan A cross section of preferably 125 mm),
The distance between the centers of the tubes is 20-29 mm (most preferably 24.5 mm),
Tube wall thickness 0.7-0.9 mm (most preferably 0.8 mm),
Number of tubes per tube bundle = 40-60 (most preferably 50),
Tube length 1,700-2,400 mm (most preferably 2,044 mm),
Arrowhead fins (preferably, not a requirement) that straddle between adjacent tubes and are thermally connected to both tubes,
Fin height 17-19 (most preferably 18.5 mm (effective height is 9.25 mm per side of the tube)),
Air transfer length fins 95 mm to 195 mm, most preferably 120 mm.

According to this most preferred embodiment, the total area of the tube bundle surface relative to the prior art ACC with the same total fan output, steam volume, and thermal conditions is 79%, as well as the total floor of this most preferred embodiment. The area is 79% of the area of the prior art ACC with the same total fan output, steam volume, and thermal conditions.

In addition, the ACC design of the present invention can be installed more easily and the overall space required within the power plant can be made smaller.

It is a perspective view of the heat exchange part of the large-scale on-site assembly type air-cooled industrial steam condenser of the prior art. It is an enlarged view of the heat exchange part of the large-scale on-site assembly type air-cooled industrial steam condenser of the prior art showing the orientation of the pipe with respect to the steam distribution manifold. FIG. 3 is a perspective view of a heat exchange portion of a large-scale on-site assembly type air-cooled industrial steam condenser (“ACC”) according to the first embodiment of the present invention. It is a perspective view of the heat exchange part of the large-scale on-site assembly type air-cooled industrial steam condenser (“ACC”) according to the 2nd Embodiment of this invention. FIG. 3 is a perspective view of a heat exchange portion of a large-scale on-site assembly type air-cooled industrial steam condenser (“ACC”) according to a third embodiment of the present invention. It is a perspective view of the heat exchange part of the large-scale on-site assembly type air-cooled industrial steam condenser (“ACC”) according to the 4th Embodiment of this invention. It is a perspective view of the cross section of the ACC tube and fin of the prior art. It is a perspective view of the mini tube and fin by one Embodiment of this invention. FIG. 3 is a perspective view of a mini tube and fins according to another embodiment of the present invention. One street of a large on-site assembly air-cooled industrial steam condenser according to an embodiment of the invention, having a paired arrangement of only V-shaped secondary heat exchange tube bundles shown in FIG. 4A. It is a side view of. FIG. 8 is an end view of a large-scale on-site assembly type air-cooled industrial steam condenser shown in FIG. FIG. 8 is a top view of the large on-site assembly air-cooled industrial steam condenser shown in FIG. 8, showing one turbine exhaust duct divided into six vertical steam headers (six streets) of six cells each. .. It is a perspective view of the tube bundle with a secondary condenser fin by one Embodiment of this invention. It is a perspective photograph of a tube bundle with a secondary condenser fin drawn in FIG.

(A-frame ACC, all with secondary tube bundles)

Referring to FIG. 2, the tube 2 is arranged in the secondary tube bundle 4. The longitudinal axis of the tube 2 is aligned parallel to the transverse axis of the tube bundle, and each tube is generally oriented 25 ° to 35 °, preferably 30 ° from the vertical. The integrated steam distribution / condensation recovery manifold 6 is attached to the bottom of each of the two secondary tube bundles 4 coupled at the top of the A-frame configuration. The steam is distributed to the pipe 2 via the integrated steam distribution / condensate recovery manifold 6, and when the steam condenses, condensate is formed in the pipe 2 and descends the pipe 2 to the integrated steam distribution / condensate recovery manifold 6. Inflow to. A single non-condensable recovery manifold 8 is attached to the tops of both tube bundles 6 to collect the non-condensable gas that travels to the tops of the tubes 2. The steam is supplied from the steam duct 10 to the integrated steam distribution / condensate recovery manifold 6 via the riser 12. The condensed water collected in the integrated steam distribution / condensate recovery manifold 6 is carried away from the ACC in the condensate recovery pipe 14.

FIG. 3 shows an embodiment very similar to the embodiment of FIG. 2, where each tube bundle 4 is attached at its top to a dedicated non-condensate recovery manifold.

(V-shaped ACC, all with secondary tube bundles)

With reference to FIGS. 4A and 4B, the tube 2 is arranged in the secondary tube bundle 4. The longitudinal axis of the tube 2 is parallel to the transverse axis of the tube bundle, and each tube is generally oriented 25 ° to 35 °, preferably 30 ° from the vertical. At the bottom of the two secondary tube bundles 4, an integrated steam distribution / condensate recovery manifold 6 coupled at an angle of 55 ° to 65 °, preferably 60 ° in a V-shape is attached. The steam is distributed to the pipe 2 via the integrated steam distribution / condensate recovery manifold 6, and the steam condenses to form condensate in the pipe 2 and descends the pipe 2 to the integrated steam distribution / condensate collective manifold. Enter into 6. A non-condensable recovery manifold 8 is attached to the tops of both tube bundles 6 to recover the non-condensable gas moving to the top of the tube 2. The steam is supplied from the steam duct 10 to the integrated steam distribution / condensate recovery manifold 6 via the riser 12. The condensed water recovered in the integrated steam distribution / condensate recovery manifold 6 is carried away from the ACC in the condensate recovery pipe 14.

The novel ACC design described above is approximately 11 meters long, 200 mm wide (or "air transfer length"), has a semi-circular tip and rear end, and has an internal height (perpendicular to the air transfer length). 18.8 mm, tube wall thickness 1.35 mm, fins brazed to both flat sides of each tube, typically 18.5 mm high, 1 inch (25.4 mm). ) May be used in any prior art tube, including the tube shown in FIG. 5 having fins with 11 spaced fins per. However, according to a more preferred embodiment, the novel ACC design of the present invention has the following features and dimensions:
No primary tube bundle, all secondary tube bundles (all tubes receive steam from the bottom, condensate from the bottom, non-condensable gas from the top),
A pair of 4, 5 (most preferred) or 6 V-shaped tube bundles per cell / fan,
A cross section of a tube with an outer diameter of 4 to 10 mm (preferably 5 to 7 mm, most preferably 6.0 mm) x 100 to 200 mm (most preferably 125 mm).
Tube center spacing 20-29 mm (most preferably 24.5 mm),
Tube wall thickness 0.7-0.9 mm (most preferably 0.8 mm)
Number of tubes per tube bundle = 40-60 (most preferably 50)
Tube length 1,700-2,400 mm (most preferably 2,044 mm)
Arrowhead fins that straddle adjacent tubes and are thermally connected to both tubes (preferably, not a requirement)
Fin height 18.5 mm (effective height is 9.25 mm per side of tube),
Air transfer length fins 95 mm to 195 mm, most preferably 120 mm.
According to this preferred embodiment, a 25-30% increase in capacity is provided for a single cell with a constant fan output, surpassing the prior art A-shaped frame design with standard tubes. ..

8 to 10 show a typical large-scale on-site assembly air-cooled industrial steam condenser according to an embodiment of the present invention, which has only a pair of V-shaped secondary heat exchange tubes shown in FIG. 4A. Is shown. The apparatus shown in FIGS. 8-10 is a 36-cell (6 streets x 6 cells) ACC, which is the most preferred embodiment of 5 tube bundle pairs per cell, but the present invention is used in any size ACC. Or any number of tube bundle pairs per cell may be used.

Claims (11)

All connected to the industrial steam production facility are large-scale on-site assembly air-cooled industrial steam condensers with secondary tube bundles.
A rectangular array of air-cooled condensate cells arranged in a plurality of rows is provided, and each of the plurality of rows includes a plurality of the air-cooled condensate cells.
Each air-cooled condenser cell contains a single fan and multiple condenser tube bundle pairs arranged in an A-shaped or V-shaped configuration, with each condenser tube bundle mounted adjacent to each other. Each of the condenser tube bundles comprises a single row of finned single channel flat tubes, each of which is oriented such that the longitudinal axis of the finned flat tube is positioned at an angle of 55 ° to 65 ° from the horizontal.
The single channel flat tube has a cross-sectional width perpendicular to the transverse and longitudinal axes of the bundle of 100 mm to 200 mm and a constant cross-sectional height parallel to the longitudinal axis of the bundle of 4-10 mm. Have
Each condenser tube bundle is attached to the bottom, distributes steam to the bottom of the finned single channel flat tube, and recovers the condensate formed from the steam during cooling within the finned single channel flat tube. It has an integrated steam distribution-condensation recovery manifold that is configured to extend along the length of the condenser tube bundle.
Each condenser tube bundle is attached to its top and extends along the length of the tube bundle parallel to each one of the integrated steam distribution-condensation recovery manifolds and is a non-condensable gas from the steam. Has a non-condensate recovery manifold, configured to recover
Each row of air-cooled condenser cells comprises a steam duct extending below the midpoint of the condenser tube bundle in the row, where the steam duct is the longitudinal axis of the condenser tube bundle in the row. It has a longitudinal axis perpendicular to, and is connected by a riser duct to the back of each integrated steam distribution-condenser recovery manifold of the condenser tube bundle in said row, with each said steam duct having each steam at one end. Connected to a turbine exhaust duct with a longitudinal axis perpendicular to the duct,
A large-scale on-site assembly air-cooled industrial steam condenser with all secondary steam bundles, in which all of the steam distributed to the condenser tube bundle is distributed from the integrated steam distribution-condensation recovery manifold . The large-scale on-site assembly type of all secondary tube bundles according to claim 1, wherein all of the condensate recovered from the finned single channel condensate is recovered in the integrated steam distribution-condensation recovery manifold. Air-cooled industrial steam condenser. The longitudinal axis of the finned single channel flat tube is positioned at an angle of 60 ° from the horizontal, all of which is claimed in claim 1 for large on-site assembly air-cooled industrial steam condensate. vessel. The single-channel flat tube with fins has a cross-sectional width of 125 mm and a cross-sectional height of 5.2 to 7 mm, all of which is described in claim 1 as a large-scale on-site assembly air-cooled industrial steam of a secondary tube bundle. Condenser. The single-channel flat tube with fins has a cross-sectional width of 125 mm and a cross-sectional height of 6.0 mm, all of which according to claim 1 is a large-scale on-site assembly air-cooled industrial steam condensate of a secondary tube bundle. vessel. The finned single channel flat tube has fins attached to the flat side of the tube, the fins having a height of 10 mm and 9-12 fins per inch (25.4 mm). A large-scale on-site assembly type air-cooled industrial steam condenser in which all of the claims 1 are secondary tube bundles. The single channel flat tube with fins has a cross-sectional width of 200 mm and a fin height of 17 to 20 mm, all of which according to claim 1 is a large-scale on-site assembly air-cooled industrial steam condensate of a secondary tube bundle. vessel. The single-channel flat tube with fins has a cross-sectional width of 200 mm and a fin height of 18.8 mm, all of which according to claim 1 is a large-scale on-site assembly air-cooled industrial steam condensate of a secondary tube bundle. vessel. The single channel flat tube with fins has a cross-sectional width of 125 mm and a cross-sectional height of 4 to 10 mm, all of which according to claim 1 is a large-scale on-site assembly type air-cooled industrial steam condensate of a secondary tube bundle. vessel. The single-channel flat tube with fins is a large-scale on-site assembly air-cooled industrial steam condenser, all of which is a secondary tube bundle, having a length of 1700 mm to 2400 mm. The large-scale on-site assembly air-cooled industrial steam condenser, all of which are secondary tube bundles, comprising 40 to 60 of the finned single channel flat tubes.

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