JP5780520B2 - Waste heat recovery boiler - Google Patents

Description

  The present invention relates to an exhaust heat recovery boiler (HRSG), and more particularly to a support structure for a heat transfer tube panel of an exhaust heat recovery boiler excited by a high-temperature and high-speed exhaust gas flow from a gas turbine.

  Recently, combined power plants have attracted attention as part of high-efficiency power generation in order to meet the rapidly increasing power demand. This combined power plant first generates power by a gas turbine, recovers heat in exhaust gas discharged from the gas turbine by an exhaust heat recovery device (exhaust heat recovery boiler), and uses steam generated in the exhaust heat recovery boiler. The steam turbine is driven to generate electricity.

  Since this combined power plant can perform power generation using a gas turbine and power generation using a steam turbine at the same time, the power generation efficiency is high and the gas turbine has excellent load responsiveness. There is also an advantage of excellent load followability that can be sufficiently handled, and it is particularly effective for a plant that performs a so-called daily start / stop operation or a weekend start / stop operation.

  However, in this combined power plant, since clean fuel such as LNG and kerosene is used, the amount of SOx and the amount of dust are reduced, but in the combustion of the gas turbine, the amount of oxygen is large and high temperature combustion is performed. Since the amount of NOx in the exhaust gas increases, an exhaust heat recovery boiler with a built-in denitration device is used.

  FIG. 7 shows a schematic system diagram of a combined power plant in which a denitration device is arranged. In FIG. 7, the high-temperature and high-speed exhaust gas 11 from the gas turbine 1 includes a superheater 3, a first evaporator 4, a denitration device 5, a second evaporator 6, installed in an exhaust heat recovery boiler (HRSG) duct 12. Heat is exchanged by sequentially contacting the economizer 7. Further, water containing the steam from the first evaporator 4 and the second evaporator 6 is sent to the brackish water separation drum 8 from the pipes 28a and 28b, respectively, and the steam separated from the brackish water separation drum 8 is saturated. After being further heated by the superheater 3 via the steam pipe 37, it is used as superheated steam for driving the steam turbine 9 via the main steam pipe 31. The steam used in the steam turbine 9 is returned to the water W by the condenser 10 and circulated to the economizer 7 by the feed water pump 30 arranged in the feed water line 32, and from the gas turbine 1 by the economizer 7. Preheated from the exhaust gas 11 and supplied into the drum 8. The water in the drum 8 descends through the downpipe 33 and is introduced into the evaporators 4 and 6 through the pipes 35a and 35b, and then returns to the drum 8 through the pipes 28a and 28b. The turbine bypass pipe 38 connected to the main steam pipe 31 may bypass the steam turbine 9 and guide the steam directly to the condenser 10.

  7 shows a steam turbine control valve 39 for adjusting the flow rate of steam to the steam turbine 9, a turbine bypass valve 40 for adjusting the amount of steam bypass by supplying steam to the steam turbine 9, and a damper for the exhaust gas duct 12. 41 is provided.

  Although the above description has explained the outline of each flow of the high-temperature and high-speed exhaust gas 11, feed water W, and steam in the combined power plant, generally, in the exhaust heat recovery boiler (HRSG), the superheater 3, the evaporation Heat exchangers such as the units 4 and 6 and the economizer 7 are incorporated, and a denitration device 5 is arranged to recover exhaust heat of the exhaust gas 11 and denitrate the exhaust gas 11.

  In FIG. 8, the perspective view of the heat exchanger tube panel 13 which comprises the heat exchanger arrange | positioned in an exhaust heat recovery boiler (HRSG) is shown. The heat transfer tube panel 13 is a heat exchanger that constitutes a heat transfer surface such as the superheater 3, the first evaporator 4, the second evaporator 6, and the economizer 7 of FIG. The headers 17 and 17 and a large number of heat transfer tubes 25 are connected between them, and fins 26 that are easy to absorb heat from the exhaust gas 11 are spirally wound around the outer periphery of the heat transfer tubes 25 and are welded. It consists of a tube 24. In the example in which such a heat transfer tube panel 13 is shown in FIG. 8, three heat transfer tube panels 13 are arranged as a unit with the panel surface facing in a direction orthogonal to the gas flow, and a plurality of these units are arranged side by side. Are bundled by a horizontal support 19 in the left-right direction of the boiler and a connecting fitting 18 along the gas flow direction.

  FIG. 9 shows a cross-sectional view of the heat transfer tube panel 13 in which the three rows of heat transfer tubes 25 are arranged in a staggered manner. FIG. 10 is a side view of the heat transfer tube panel of FIG. 9 and FIG. The side view of the state before connecting a header is shown.

  The fin tubes 24 (consisting of the heat transfer tubes 25 and the fins 26) having the configurations shown in the cross-sectional views, the side views, and the side view before assembly in FIG. 9, FIG. 10, and FIG. This is an example in which the outside is bundled with a horizontal support 19 and used as one heat transfer tube panel 13. Here, each heat transfer tube panel 13 includes a heat transfer tube 25 and a fin tube 24 including fins 26 spirally welded around the heat transfer tube 25, and an example in which the fin tubes 24 are arranged in two or three rows in a staggered manner is shown. .

  When the three rows of heat transfer tube groups shown in FIG. 9 to FIG. 11 are manufactured as one heat transfer tube panel unit, a honeycomb made of corrugated plates above and below the fin tube 24 between the upper and lower headers 17, 17. The important portions of the supports 29a, 29b, and 29c that are in contact with each other are welded to form a welded portion Y.

  FIG. 12 shows a bird's-eye view of HRSG. HRSG is a steam generator in which a heat transfer tube panel 13 shown in FIG. In the conventional HRSG, the high-temperature and high-speed exhaust gas 11 of about 20 m / s from the gas turbine 1 flows into the duct 12 at a temperature of about 650 ° C. and is absorbed by the heat transfer tube panel 13 to a relatively low temperature. Is discharged from the chimney 14.

  FIG. 13 is a side view showing a heat transfer tube panel structure arranged inside the exhaust gas inlet portion of HRSG. The duct 12 is supported on the ground 15 via a frame 16. The heat transfer tube panels 13A, 13B, and 13C are suspended and supported by the headers 17A, 17B, and 17C, respectively. Exhaust gas 11 of about 20 m / s acts at about 650 ° C. on the heat transfer tube panels 13A, 13B, and 13C, and the heat transfer tube panels 13A, 13B, and 13C swing in the front-rear direction and the left-right direction with respect to the gas flow.

  In order to suppress the vibration of the heat transfer tube panels 13A, 13B, and 13C, the heat transfer tube panels 13A, 13B, and 13C shown in FIG. By increasing the frequency, the vibration of the exhaust gas passing through the heat transfer tube group has been suppressed (see Japanese Patent No. 3625948).

  However, in recent years, gas turbines have become larger in size, and the drift of exhaust gas 11 having a high temperature and high flow rate in the duct 12 has increased, and the vibration fluctuation of the heat transfer tube panel 13 due to the high temperature and high speed exhaust gas 11 has been amplified. It has become a problem that the horizontal support 19 in the left-right direction of the boiler orthogonal to the gas flow is damaged.

  In the invention described in Patent Document 1 below, a measure is taken to eliminate vibration fluctuation of the heat transfer tube panel in a configuration in which a heat transfer tube (fin tube) with fins is sandwiched and fixed by a horizontal support.

Japanese Patent No. 3625948

  As described above, in the invention described in Patent Document 1, the horizontal support is installed with an increased number of stages in order to solve the vibration fluctuation of the heat transfer tube panel, but vibration due to swirling component drift cannot be suppressed. Was a problem.

  By increasing the size of the gas turbine, the exhaust gas flowing into the exhaust heat recovery boiler (HRSG) is about 50 m / s, which is a much higher temperature and higher speed than the conventional flow rate of about 20 m / s, and about 650. It is a hot gas of ℃. Therefore, if drift occurs in the high-speed and high-temperature exhaust gas in the HRSG, a flow of high-temperature and high-speed exhaust gas of about 100 m / s may partially occur locally, and the conventional horizontal support vibrates the heat transfer tube panel. The heat transfer tube panel contacted the duct wall surface of the HRSG and damaged not only the heat transfer tube panel but also the duct.

  For this reason, even if the number of reinforcing members is simply increased to reinforce the horizontal support, the heat recovery efficiency is reduced to block the heat transfer area of the heat transfer tube, and the mass of the horizontal support reinforcing member is several times larger. There was a problem to be solved such as an increase.

  Accordingly, an object of the present invention is to solve the above-mentioned problems in the prior art, and a heat transfer tube excited by a swirling flow of a high-temperature and high-speed gas turbine exhaust gas at about 650 ° C., which is about 50 m / s, and in some cases 100 m / s An object of the present invention is to provide an exhaust heat recovery boiler that reduces stress due to panel vibration and enables stable operation.

The above object of the present invention is achieved by the following means.
According to the first aspect of the present invention, a heat transfer tube panel in which a plurality of heat transfer tubes are bundled in a duct into which the exhaust gas from the gas turbine flows is suspended and arranged to recover the heat of the exhaust gas from the gas turbine in the heat transfer tube. In a heat recovery steam generator that generates steam, a plurality of horizontal supports with a predetermined width are installed in the vertical direction to bundle the heat transfer tube panels in the horizontal direction perpendicular to the flow direction of the exhaust gas, and several heat transfer tubes on both sides of the heat transfer tube panel In the exhaust heat recovery boiler, the width of the horizontal support at each stage in the portion is wider than the predetermined width.

  The invention according to claim 2 is characterized in that the several heat transfer tube portions on both sides of each heat transfer tube panel are approximately three times as wide as the horizontal support with a predetermined width. It is.

  According to a third aspect of the present invention, the heat transfer tube comprises a finned heat transfer tube having fins wound around the outer periphery thereof, and a honeycomb support comprising a corrugated baffle plate that sandwiches and fixes the finned heat transfer tube from the left and right of the finned heat transfer tube A horizontal support is provided outside the honeycomb support, and the heat transfer tube portions on both sides of each heat transfer tube panel have both the honeycomb support and the horizontal support wider than the predetermined width of the horizontal support. The exhaust heat recovery boiler according to claim 1 or 2.

  According to a fourth aspect of the present invention, a heat transfer tube panel in which a plurality of heat transfer tubes are bundled in a duct into which the exhaust gas from the gas turbine flows is suspended and arranged to recover the heat of the exhaust gas from the gas turbine in the heat transfer tubes. In the existing exhaust heat recovery boiler that generates steam, multiple stages of horizontal support with a predetermined width that bundles the heat transfer tube panels in the horizontal direction perpendicular to the flow direction of the exhaust gas are provided in the vertical direction, and each heat transfer tube as a horizontal support for each stage Several heat transfer tube portions on both sides of the panel are arranged on the top and bottom of the horizontal support with reinforcing horizontal supports having substantially the same width as the horizontal support, and from the outside of the reinforcing horizontal support of the heat transfer tube panel to which the reinforcing horizontal support is attached. An exhaust heat recovery boiler comprising an opening prevention plate that sandwiches a reinforcing horizontal support and supports the reinforcing horizontal support.

  According to a fifth aspect of the present invention, in the exhaust heat recovery boiler according to the fourth aspect, the reinforcing horizontal support has a structure in which a rib is provided at the center of the outer side, and an opening prevention plate is supported by the rib. is there.

  According to a sixth aspect of the present invention, there is provided a honeycomb support comprising a corrugated baffle plate which is composed of a heat transfer tube with fins in which fins are wound around an outer peripheral portion, and is sandwiched and fixed from the left and right of the heat transfer tube with fins. A horizontal support is provided outside the support, and several heat transfer tube portions on both sides of each heat transfer tube panel are provided with a reinforced honeycomb support having a width substantially the same as the honeycomb support above and below the honeycomb support, and further above and below the horizontal support. The exhaust heat recovery boiler according to claim 4 or 5, wherein a reinforcing horizontal support having substantially the same width as the horizontal support is disposed.

(Function)
FIG. 1 shows a vibration isolation structure of the heat transfer tube panel 13 as a whole of the HRSG according to the present invention. A heat transfer tube in which a mass M of a plurality of heat transfer tubes 25 (or fin tubes 24 in which fins 26 are wound around the outer periphery of the heat transfer tube 25) and a horizontal support 19 (or horizontal support 19 and honeycomb support 29) may be bundled by the horizontal support 19 The panel 13 is about 20% of the total number of heat transfer tubes (32 in the example shown in FIG. 1) in the direction orthogonal to the flow direction of the exhaust gas 11 (left and right direction) (in the example shown in FIG. 1). The width H of the horizontal support 19 at the end of the panel in the range of 6) (the range of width L1 × 2 in FIG. 1) is 3H, which is three times that of the prior art. Specifically, a support 19U is additionally provided at the upper part of the horizontal support 19, and 19D is additionally provided at the lower part. Accordingly, the horizontal support 19 has a total length L in a direction (left-right direction) orthogonal to the gas flow direction, and a horizontal support structure (support 19U, horizontal support 19 having a length L1 × 2 and a width 3H at both ends of the panel. And a lower support 19D) and a horizontal support 19 having a width H and a length L2 therebetween.

  It will be described below using the vibration system of the panel 13 that the addition of the upper and lower supports 19U and 19D is effective for reducing the vibration displacement in the left-right direction of the panel 13 and reducing the stress at the time of collision of the panel 13. explain.

  First, the reduction of the vibration of the panel 13 in the left-right direction (direction orthogonal to the gas flow) will be described. The vibration system of the conventional structure shown in FIG. 2 and the panel structure according to the present invention shown in FIG. 1 are shown in FIGS. 4 and 3, respectively. In the vibration system of the conventional structure shown in FIG. 4, the mass M of the 32 heat transfer tubes 25 in the panel 13 in FIG. 2 and the rigidity K of the horizontal support 19 are as shown in the following equations (1) and (2): The mass M is proportional to the length L, and the stiffness K is proportional to the Young's modulus E and the width H of the horizontal support 19 and inversely proportional to the length L.

The natural frequency f of this vibration system is proportional to the 1/2 power of (K / M) as shown in Equation (3).
M∝L (1)
K∝E × H / L (2)
f∝ (K / M) ^1/2 (3)
2 and 4, in the conventional structure, the vibration direction of the 32 heat transfer tubes 25 bundled by the horizontal support 19 is the same direction (so-called in-phase vibration), and the vibration displacement of the entire panel 13 is large. Become.

On the other hand, the vibration system of the structure of the heat transfer tube panel 13 according to the present invention is a system in which three vibration systems shown in FIG. 3 are connected. In FIG. 3, the mass M1 and the rigidity K1 of the number of the heat transfer tubes 25 of about 20% at each end of the panel 13 (3 × 2 in the embodiment) and about 60 in the panel 13 other than the both ends of the panel 13 respectively. There is a relationship represented by the following equations (4), (5), and (6) between the mass M2 and the rigidity K1 corresponding to the number of heat transfer tubes of% (20 in this embodiment).
M1∝M / L × L1 = M / 5.3 (4)
K1∝E × 3H / L1 = 16E × H / L = 16K (5)
M2 = M / L × L2 = M / 1.6 (6)
K2 = E * H / L2 = 1.6 * E * H / L = 1.6K (7)
In addition, the natural frequencies f1 and f2 of the M1-K1 vibration system and the M2-K2 vibration system are expressed by equations (8) and (9), respectively.
f1∝ (K1 / M1) ^1/2 = 9.2 × f (8)
f2∝ (K2 / M2) ^1/2 = 1.6 × f (9)
By dividing equation (8) by equation (9), the ratio of f1 to f2 is obtained as in equation (10).
f1 / f2 = 5.73 (10)
As shown in Expression (10), the natural frequency f1 of the M1-K1 vibration system is 5.73 times the natural frequency f2 of the M2-K2 vibration system. In this way, each vibration system is formed by forming three vibration systems having different natural frequencies (the M1-K1 vibration system at the left end of the panel, the M2-K2 vibration system at the center of the panel, and the M1-K1 vibration system at the right end of the panel). By utilizing the difference in vibration direction (so-called phase difference), the vibration displacement δ of the entire panel 13 can be reduced. As a result, the collision load between the ends of adjacent panels 13 and the end of the panel 13 and the casing (duct) 12) can be reduced.

  Next, the stress reduction at the time of collision of the panel 13 will be described. In the structure according to this embodiment shown in FIG. 1 with respect to the width H of the conventional horizontal support 19 shown in FIG. 2, the horizontal support structure having a width of 3H (upper reinforcing support 19U, horizontal support 19 and lower reinforcing support). 19D) is tripled. Thus, in the support structure according to the present embodiment, the area of the panel 13 that receives the collision load is three times that of the conventional structure, and the stress during the collision of the heat transfer tube panel 13 can be reduced.

  In the above description, an example in which the width of the end portion of the heat transfer tube panel 13 is three times the width H of the conventional horizontal support 19, or the reinforcing upper support 19U, the horizontal support 19 and the reinforcing lower support 19D for reinforcement) In the present invention, the horizontal support 19 has been described as being approximately three times as wide as the width H. In the present invention, the width of the reinforcing upper support 19U and the reinforcing lower support 19D provided at the end of the heat transfer tube panel 13 is the same as that of the horizontal support 19. It is not necessarily the same as the width H, and may be a wider width if necessary.

  As described above, according to the present invention, the width of the horizontal support 19 at both ends of the heat transfer tube panel 13 is different from the width (H) of the horizontal support 19 at the center of the panel 13, thereby Left end vibration system, panel center vibration system, panel right end vibration system), and by using the phase difference of vibration in these three vibration systems to reduce the left-right vibration of the panel 13, it is adjacent The collision load between the end portions of the panels 13 or between the end portions of the panel 13 and the casing can be reduced. Moreover, the stress which generate | occur | produces at the time of the collision of the end part of the heat exchanger tube panel 13 can also be reduced by making the width | variety of the horizontal support 19 of the edge part of the panel 13 into about 3 times the conventional. By these actions, an exhaust heat recovery boiler vibration isolation structure that contributes to stable operation of the exhaust heat recovery boiler is obtained.

  According to the first aspect of the present invention, high-temperature and high-speed gas turbine exhaust gas of about 50 m / s or more, locally about 100 m / s is introduced into the duct of the exhaust heat recovery boiler, and the exhaust gas is swirled. Even so, the vibration displacement of the heat transfer tube panel can be reduced by reinforcement consisting of a simple structure of the horizontal support of the heat transfer tube panel, and the adjacent heat transfer tube panel ends or between the heat transfer tube panel ends and the exhaust heat recovery boiler casing The anti-vibration structure that contributes to the stable operation of the exhaust heat recovery boiler can be obtained.

  According to the invention described in claim 2, in addition to the effect of the invention described in claim 1, the width of the horizontal support at the end of the heat transfer tube panel is approximately three times that of the conventional one, so that it occurs when the end of the panel collides. Since the stress to be reduced can be reduced, a vibration isolation structure that contributes to stable operation of the exhaust heat recovery boiler can be obtained.

  In addition to the effect of the invention of claim 1 or 2, the invention described in claim 3 is sandwiched from the left and right of the finned heat transfer tube when the heat transfer tube is composed of a finned heat transfer tube in which fins are wound around the outer periphery. A honeycomb support made of a corrugated baffle plate to be fixed, and a horizontal support is provided outside the honeycomb support, and several heat transfer tube portions on both sides of each heat transfer tube panel have both the honeycomb support and the horizontal support having the same width. By making it wider than the predetermined width of the horizontal support, the vibration displacement of the heat transfer tube panels can be reduced, and the collision force between adjacent heat transfer tube panel ends or between the heat transfer tube panel ends and the exhaust heat recovery boiler casing can be reduced.

  According to the invention of claim 4, even when the horizontal support cannot be reinforced by welding in the existing heat recovery steam generator, the heat transfer tube is held by the opening prevention plate that supports the reinforced horizontal support from the outside of the reinforced horizontal support. The width of the horizontal support at the end of the panel can be approximately three times that of the conventional one, and even if the high-temperature high-speed gas turbine exhaust gas is introduced into the duct of the exhaust heat recovery boiler and the exhaust gas turns into a swirl flow, The vibration displacement of the heat transfer tube panels can be reduced, and the collision force between adjacent heat transfer tube panel ends or between the heat transfer tube panel ends and the exhaust heat recovery boiler casing can be reduced, contributing to stable operation of the exhaust heat recovery boiler. An anti-vibration structure is obtained.

  According to the fifth aspect of the present invention, in addition to the effect of the fourth aspect of the invention, the reinforcing horizontal support has a rib at the center of the outer side of the reinforcing horizontal support, and the opening preventing plate is supported by the rib. Can be easily retained without welding.

  In addition to the effect of the invention of claim 4 or 5, the invention of claim 6 is sandwiched from the left and right of the finned heat transfer tube when using a finned heat transfer tube with fins wound around the outer periphery of the heat transfer tube. A honeycomb support made of corrugated baffle plates to be fixed is provided, a horizontal support is provided outside the honeycomb support, and several heat transfer tube portions on both sides of each heat transfer tube panel are substantially the same as the honeycomb support above and below the honeycomb support. By providing a reinforcing honeycomb support having a width, and further providing a reinforcing horizontal support having the same width as the horizontal support above and below the horizontal support, vibration displacement of the heat transfer tube panels can be reduced. The collision force between the heat transfer tube panel end and the exhaust heat recovery boiler casing can be reduced.

It is a side view which shows the vibration isolating structure of a heat exchanger tube panel in the whole HRSG by this invention. It is a side view which shows the vibration isolating structure of a heat exchanger tube panel in the whole HRSG by a prior art. 2 shows a vibration system of the panel structure of the HRSG according to the present invention shown in FIG. 3 shows a vibration system of the HRSG panel structure according to the prior art shown in FIG. It is a partial perspective view which shows the structure at the time of reinforcing the horizontal support of the heat exchanger tube panel of one Example of this invention. It is a partial perspective view which shows the structure at the time of reinforcing the horizontal support of the heat exchanger tube panel of one Example of this invention. A schematic system diagram of a combined power plant with a denitration system is shown The perspective view of the heat exchanger tube panel which comprises the heat exchanger arrange | positioned in an exhaust heat recovery boiler (HRSG) is shown. It is sectional drawing of the heat exchanger tube panel arrange | positioned in an exhaust heat recovery boiler. It is a side view of the heat exchanger tube panel of FIG. It is a side view before the assembly of the heat exchanger tube panel of FIG. It is a bird's-eye view of HRSG of the Example of this invention. It is a side view of the inlet_port | entrance part of HRSG of FIG. It is AA sectional view taken on the line of FIG.

Embodiments of the present invention will be described with reference to the drawings.
The bird's-eye view of the exhaust heat recovery boiler (HRSG) shown in FIG. 12 and the side view of the inside of the duct in which the heat transfer tube panel on the inlet side of the HRSG in FIG. 13 is also adapted to the embodiment of the present invention. AA line sectional drawing is shown.

  The heat transfer tube panels 13A, 13B, and 13C according to the embodiment of the present invention are sequentially arranged along the flow direction of the exhaust gas 11 from the gas turbine. FIG. 14 shows an example in which, for example, the heat transfer tube panel 13A is arranged in three rows in parallel in the direction orthogonal to the gas flow of the exhaust gas 11, left, center, and right, and the heat transfer tube panel 13AL, the heat transfer tube panel 13AM, It consists of a heat transfer tube panel 13AR.

  The heat transfer tube panel 13AL, the heat transfer tube panel 13AM, and the heat transfer tube panel 13AR are provided with a connecting bracket 18 in the front-rear direction of the duct 12 and a horizontal support 19 (honeycomb support 29 in the transverse direction of the duct 12, although illustrated. Are not arranged). The connecting fitting 18 is provided at the end of the horizontal support 19.

  Each heat transfer tube panel 13AL, heat transfer tube panel 13AM, and heat transfer tube panel 13AR are connected to upper and lower headers 17A, 17B, and 17C, respectively.

  FIG. 5 is a perspective view of an anti-vibration reinforcing structure when the fin tube 24 composed of two rows of heat transfer tubes 25 and fins 26 used in this embodiment is bundled as a single heat transfer tube panel 13 with a honeycomb support 29 and a horizontal support 19. It shows with. 5 shows only a part of the fin tube 24 by a dotted line, and FIG. 5 is a partial perspective view of one end side of the honeycomb support 29 and the horizontal support 19 provided outside thereof. The ends of the horizontal support 19 are connected to each other by a horizontal support end reinforcing plate 20. Although the heat transfer tube structure not provided with the honeycomb support 29 is not shown, the vibration-proof reinforcement of the present embodiment is also applied to a structure in which the honeycomb support 29 and the fin tube 24 are not provided and the heat transfer tube 25 is bundled by the horizontal support 19. Structure can be applied.

  FIG. 5 shows an example in which about 32 × 2 rows of fin tubes 24 are bundled by one honeycomb support 29 and one horizontal support 19. Then, as shown in FIG. 5, a honeycomb support 29 made of a corrugated baffle plate having a predetermined width (H) and an upward reinforcing honeycomb support 29U made of a corrugated baffle plate having approximately the same width (H) above and below both ends of the horizontal support 19. The upper horizontal support 19U, the lower honeycomb support 29D, and the lower horizontal support 19D are provided in portions corresponding to 6 × 2 rows of the fin tubes 24, and are connected to each other by welding. Therefore, the fin tube 24 including the heat transfer tubes 25 and the fins 26 can be supported by the support structure having a width about three times at the upper and lower ends of the honeycomb support 29 and the horizontal support 19.

  A filling member 43 is embedded in the space surrounded by the horizontal support 19, the horizontal support end reinforcing plate 20, and the honeycomb support 29.

  The predetermined width (H) is 30 to 50 mm. Moreover, the mutual contact part of the horizontal support 19, the horizontal support edge part reinforcement board 20, and the honeycomb support 29 can be suitably welded at the time of manufacture in a heat exchanger manufacturing factory.

  In this case, the portion where the stress is strongly applied is the corner portion S2 of the honeycomb support 29 of FIG. 5 where the corner portion S1, the upper honeycomb support 29U, and the lower honeycomb support 29D are eliminated, and the width H of the honeycomb support 29 alone. In the analysis, the value was about 40% of that when using the conventional single-width horizontal support 19.

  Next, as a second embodiment of the present invention, FIG. 6 is a perspective view of an anti-vibration reinforcing structure when two rows of fin tubes 24 of an existing exhaust heat recovery boiler (HRSG) are bundled by a honeycomb support 29 and a horizontal support 19. Show. The ends of the horizontal support 19 are connected to each other by a horizontal support end reinforcing plate 20. In FIG. 6, only a part of the fin tube 24 is indicated by a dotted line, and a heat transfer tube structure not provided with the honeycomb support 29 is not shown, but the honeycomb support 29 and the fin tube 24 are not provided, and the horizontal structure is horizontal. The anti-vibration reinforcing structure of this embodiment can also be applied to a structure in which the heat transfer tubes 25 are bundled by the support 19.

  In the existing heat recovery steam generator (HRSG), when the honeycomb support 29 and the horizontal support 19 are reinforced, the heat transfer tube panel 13 cannot be removed, and the heat transfer tubes of the honeycomb support 29 and the horizontal support 19 as shown in FIG. Since the upper honeycomb support 29U, the upper horizontal support 19U, the lower honeycomb support 29D, and the lower horizontal support 19D cannot be welded to each other as in the case of the attachment to the panel 13, the upper honeycomb support 29U and the lower honeycomb support FIG. 6 shows an example in which 29D and an upper horizontal support 19U and a lower horizontal support 19D are attached to the top and bottom of the honeycomb support 29 and the horizontal support 19, respectively, and about 32 × 2 rows of fin tubes 24 are bundled.

  Then, as shown in FIG. 6, a honeycomb support 29 made of a corrugated baffle plate having a predetermined width (H) and an upper honeycomb support 29U for reinforcement made of a corrugated baffle plate having approximately the same width (H) above and below both ends of the horizontal support 19 are provided. The upper horizontal support 19U, the lower honeycomb support 29D, and the lower horizontal support 19D are provided in portions corresponding to 6 × 2 rows of the fin tubes 24, respectively, and the reinforcing honeycomb supports 29U and 29D and the horizontal supports 19U and 19D are provided. The structure is supported by a plurality of opening prevention plates 22.

  Reinforcing honeycomb supports 29U and 29D made of corrugated baffle plates having a predetermined width (H) are attached to the top and bottom of the existing honeycomb support 29, and reinforcing horizontal supports 19U and 19D are attached to the outside of the top and bottom of the existing horizontal support 19. Attach to. The reinforcing horizontal support 19U and horizontal support 19D have substantially the same width as that of the existing horizontal support 19, and in the heat transfer tube panel 13 using 32 fin tubes 24, six fin tubes 24 at both end portions × Attach to the outer circumference of two rows.

  After that, ribs 19a for 6 × 2 rows of fin tubes 24 are attached to the outer periphery of the existing horizontal support 19, and a pair of gates for 6 × 2 rows of fin tubes 24 at both ends from the outside of the horizontal support 19 are attached. The mold opening prevention plate 22 is inserted from above and below, and the bottom of the portal opening prevention plate 22 is supported by the rib 19a.

  As shown in FIG. 6, in the case of the heat transfer tube panel 13 composed of two rows of fin tubes 24 arranged in a staggered manner, the portal-shaped opening prevention plate 22 is inclined with respect to the longitudinal direction of the existing horizontal support 19 for reinforcement. By inserting from the outside of the support 19U and the support 19D, the support 19U and the support 19D for reinforcement that are not welded can be stably held.

  In the case of the heat transfer tube panel 13 including the fin tubes 24 arranged in parallel rather than the staggered arrangement, the support 19U and the support 19D for reinforcing the portal-shaped opening prevention plate 22 in a direction orthogonal to the longitudinal direction of the existing horizontal support 19 are provided. By inserting from the outside, the support 19U for reinforcement and the support 19D which are not welded can be stably held.

  According to the finite element method analysis when the reinforcing honeycomb support 29U and 29D and the horizontal support 19U and D are held by the gate-shaped opening prevention plate 22 while being inclined with respect to the longitudinal direction, the honeycomb supports 29U and 29D of FIG. The most stressed portion indicated by the corner portion S3 was 70% of the stress when the conventional single-width honeycomb support 29 and the horizontal support 19 were used.

  In the embodiment of the present invention, the heat transfer tube panel 13 using the fin tube 24 provided with the fins 26 around the heat transfer tubes 25 is illustrated and described. However, the heat transfer tubes in which the fins 26 are not arranged around the heat transfer tubes 25 are described. The reinforcing structure of the horizontal support 19 of the present invention can also be applied to the panel 13.

  The widths of the reinforcing upper support 19U, the reinforcing lower support 19D, and the honeycomb supports 29U and 29D provided at the ends of the heat transfer tube panel 13 described in the above embodiment are the width H of the horizontal support 19 and the width H of the honeycomb supports 29U and 29D. The width is not necessarily the same, and may be wider if necessary.

  The horizontal support reinforcement structure of the heat transfer tube panel according to the present invention tends to increase the size of the gas turbine. The availability is expected to increase further.

DESCRIPTION OF SYMBOLS 1 Gas turbine 3 Superheater 4 1st evaporator 5 Denitration apparatus 6 2nd evaporator 7 Carbon-saving device 8 Brackish water separation drum 9 Steam turbine 10 Condenser 11 Exhaust gas 12 Waste heat recovery boiler (HRSG) duct 13A Gas flow Front heat transfer tube panel 13B, gas flow center heat transfer tube panel 13C Gas flow rear heat transfer tube panel 13AL, 13BL, 13CL Left heat transfer tube panel 13AM, 13BM, 13CM Central heat transfer tube panel 13AR, 13BR, 13CR Right side heat transfer tube panel Heat transfer tube panel 14 Chimney 15 Ground 16 Frame 17A, 17B, 17C Upper, lower header 18 Connecting bracket 19 Horizontal support 19U, 19D Horizontal support 19a Rib for reinforcement
20 Horizontal support end reinforcing plate 22 Opening prevention plate 24 Fin tube 25 Heat transfer tube 26 Fin 28a, 28b Pipe line 29 Honeycomb support 29U, 29D Reinforcing honeycomb support 30 Water supply pump 31 Main steam pipe 32 Water supply line 33 Rain pipe 35a, 35b Pipeline 37 Saturated steam pipe 38 Turbine bypass pipe 39 Steam turbine control valve 40 Turbine bypass valve 41 Damper 43 Filling member W Water Y Welded part

Claims (6)

  Exhaust heat recovery in which a heat transfer tube panel that bundles a plurality of heat transfer tubes is suspended in a duct through which the exhaust gas from the gas turbine flows, and the heat of the exhaust gas from the gas turbine is recovered in the heat transfer tube to generate steam. In the boiler, a horizontal support with a predetermined width that bundles the heat transfer tube panels in the horizontal direction perpendicular to the flow direction of the exhaust gas is provided in multiple stages in the vertical direction, and the horizontal support of each stage in several heat transfer tube parts on both sides of the heat transfer tube panel is provided. An exhaust heat recovery boiler having a width wider than the predetermined width.   2. The exhaust heat recovery boiler according to claim 1, wherein several heat transfer tube portions on both sides of each heat transfer tube panel have a width approximately three times that of a horizontal support having a predetermined width.   The heat transfer tube is composed of a finned heat transfer tube with fins wound around the outer periphery, and provided with a honeycomb support made of a corrugated baffle plate that sandwiches and fixes the finned heat transfer tube from the left and right sides of the finned heat transfer tube. 3. A horizontal support is provided on each of the heat transfer tube panels, and the width of the honeycomb support and the horizontal support of both of the heat transfer tube portions on both sides of each heat transfer tube panel is made wider than a predetermined width of the horizontal support. Waste heat recovery boiler.   A heat transfer tube panel in which a plurality of heat transfer tubes are bundled in a duct through which the exhaust gas from the gas turbine flows is suspended and arranged so that the heat of the exhaust gas from the gas turbine is collected in the heat transfer tube to generate steam. In the heat recovery boiler, a plurality of horizontal supports with a predetermined width are bundled in the vertical direction to bundle the heat transfer tube panels in the horizontal direction perpendicular to the flow direction of the exhaust gas, and several heat transfer tubes on both sides of each heat transfer tube panel are provided as horizontal supports in each step. The heat pipe portion is provided with reinforcing horizontal supports having substantially the same width as the horizontal support above and below the horizontal support, and the reinforcing horizontal support is sandwiched from outside the reinforcing horizontal support of the heat transfer tube panel to which the reinforcing horizontal support is attached. An exhaust heat recovery boiler provided with an opening prevention plate for supporting a support.   The exhaust heat recovery boiler according to claim 4, wherein the reinforcing horizontal support has a configuration in which a rib is provided at a center of the outer side thereof, and an opening prevention plate is supported by the rib.   The heat transfer tube is composed of a finned heat transfer tube with fins wound around the outer periphery, provided with a honeycomb support made of corrugated baffle plates that are sandwiched and fixed from the left and right of the finned heat transfer tube, and a horizontal support is provided outside the honeycomb support The several heat transfer tube portions on both sides of each heat transfer tube panel are provided with reinforcing honeycomb supports having substantially the same width as the honeycomb support above and below the honeycomb support, and further having substantially the same width as the horizontal support above and below the horizontal support. The exhaust heat recovery boiler according to claim 4 or 5, wherein a reinforced horizontal support is arranged.

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