JP2016099047A - Fire-tube type boiler and exhaust heat recovery system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To extend a life by suppressing generation of local heat stress with respect to an exhaust gas introduction chamber at boiler startup in a fire-tube type boiler and an exhaust heat recovery system.SOLUTION: The fire-tube type boiler includes: the exhaust gas introduction chamber 102 provided in one of water chambers 101; an exhaust gas discharge chamber 103 provided in the other water chamber 101; an exhaust gas fire-tube group 104 comprising multiple fire-tubes 141a, 142a, 143a communicating the exhaust gas introduction chamber 102 to the exhaust gas discharge chamber 103 while penetrating through the water chambers 101; and multiple split exhaust gas introduction chambers 121, 122, 123 provided as the exhaust gas introduction chamber 102 while being separated apart from one another at predetermined distance.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a smoke tube boiler that is mounted on a ship or the like and heats water by the heat of exhaust gas, and an exhaust heat recovery system to which this smoke tube boiler is applied.

  The smoke tube type composite boiler is configured such that a plurality of smoke tube groups through which exhaust gas of a diesel engine flows is provided in a water chamber, and a plurality of smoke tubes through which combustion gas of an oil-fired boiler flows. Therefore, the exhaust gas flows through the plurality of smoke pipes, so that the heat of the exhaust gas can be recovered by water. When the diesel engine is stopped, the oil-fired boiler is operated and the combustion gas flows through the plurality of smoke pipes. Thus, the heat of the combustion gas can be recovered with water.

  As such a smoke tube type boiler, there exists a thing described in the following patent document, for example.

JP 09-329301 A International Publication No. 2013/128484

  The above-described smoke tube type composite boiler is provided with an exhaust gas introduction chamber at the lower part of the water chamber, and an exhaust gas discharge chamber at the upper part, and the exhaust gas introduction chamber and the exhaust gas discharge chamber are connected by a plurality of smoke pipes penetrating the water chamber. Configured. In this case, the exhaust gas introduction chamber is divided into a plurality of partitions by partition walls because exhaust gas is introduced from a plurality of diesel engines. When the flue-tube type composite boiler configured as described above is started, when exhaust gas is introduced from the lower part of the exhaust gas introduction chamber, the temperature of the exhaust gas introduction chamber rises in order from the lower part. The exhaust gas introduction chamber is thermally expanded when the temperature of the lower part rises, so that the lower part is deformed so that the lower part spreads outward with respect to the upper part. However, since the exhaust gas introduction chamber is divided into a plurality of partitions with the partition fixed inside, it cannot be uniformly thermally deformed, and stress is applied to the upper end of the partition (the connection portion with the lower part of the water chamber). There is a risk of acting and breaking.

  This invention solves the subject mentioned above, and it aims at providing the flue-tube type boiler and exhaust heat recovery system which suppress generation | occurrence | production of a thermal stress locally with respect to an exhaust gas introduction chamber at the time of boiler starting.

  In order to achieve the above object, a smoke tube boiler according to the present invention includes an exhaust gas introduction chamber provided in one of the water chambers, an exhaust gas discharge chamber provided in the other of the water chambers, the exhaust gas introduction chamber, and the exhaust gas discharge. And an exhaust gas smoke tube group composed of a plurality of smoke tubes that communicate with each other through the water chamber, and the exhaust gas introduction chamber is composed of a plurality of divided exhaust gas introduction chambers spaced apart from each other by a predetermined distance. It is characterized by that.

  Therefore, the exhaust gas introduction chamber provided in one of the water chambers is composed of a plurality of divided exhaust gas introduction chambers separated by a predetermined distance. In this divided exhaust gas introduction chamber, the temperature rises in order from the bottom. Each divided exhaust gas introduction chamber is thermally expanded when the temperature of the lower portion rises, so that the lower portion of the divided exhaust gas introduction chamber is deformed so as to spread outward. At this time, since each divided exhaust gas introduction chamber is individually configured, the lower portion is uniformly thermally deformed, and stress is not concentrated on the upper end portion of the side wall on the connection portion side with the water chamber. . As a result, it is possible to suppress the generation of thermal stress locally with respect to the exhaust gas introduction chamber when the boiler is started.

  In the smoke pipe boiler according to the present invention, the divided exhaust gas introduction chamber has one end fixed to the water chamber, the other end provided with the exhaust gas introduction portion, and a gap between the adjacent divided exhaust gas introduction chambers. It is characterized by that.

  Accordingly, one end of the divided exhaust gas introduction chamber is fixed to the water chamber, and the other end where the exhaust gas introduction portion is provided has a gap between the adjacent divided exhaust gas introduction chamber, so that the divided exhaust gas introduction chamber Since the end portion on the side to be introduced becomes free, the divided exhaust gas introduction chamber can be deformed so as to freely spread outside without being restrained at the time of startup.

  In the smoke tube boiler according to the present invention, the divided exhaust gas introduction chamber has a hollow box shape, and one end thereof is fixed to the water chamber.

  Therefore, since the divided exhaust gas introduction chamber has a hollow box shape, the divided exhaust gas introduction chamber can be uniformly deformed so that the lower part extends outward.

  In the smoke tube boiler of the present invention, a furnace provided in one of the water chambers, a combustion gas discharge chamber provided in the other of the water chambers, and the furnace and the combustion gas discharge chamber pass through the water chamber. A flue gas flue group for combustion gas comprising a plurality of communicating flue tubes is provided.

  Therefore, by providing the furnace, the combustion gas discharge chamber, and the exhaust gas smoke tube group, it can be applied as a composite boiler, and versatility can be improved.

  In addition, the exhaust heat recovery system of the present invention includes the flue-tube boiler and a plurality of combustors that supply exhaust gas to the plurality of divided exhaust gas introduction chambers.

  Therefore, it is possible to extend the life by suppressing the generation of thermal stress locally to the exhaust gas introduction chamber when the boiler is started, and it is possible to improve the boiler operating rate.

  According to the smoke tube boiler and the exhaust heat recovery system of the present invention, it is possible to suppress the generation of thermal stress locally to the exhaust gas introduction chamber when the boiler is started.

FIG. 1 is a schematic configuration diagram illustrating an exhaust heat recovery system to which the smoke tube boiler according to the first embodiment is applied. FIG. 2 is a schematic plan view showing an exhaust gas introduction chamber of a smoke tube boiler. FIG. 3 is a schematic plan view showing a modification of the exhaust gas introduction chamber of the smoke tube boiler. FIG. 4 is a schematic plan view showing a modification of the exhaust gas introduction chamber of the smoke tube boiler. FIG. 5 is a schematic configuration diagram illustrating an exhaust heat recovery system to which the smoke pipe boiler according to the second embodiment is applied.

  Exemplary embodiments of a smoke tube boiler and an exhaust heat recovery system according to the present invention will be described below in detail with reference to the accompanying drawings. In addition, this invention is not limited by this embodiment, and when there are two or more embodiments, what comprises combining each embodiment is also included.

[First Embodiment]
FIG. 1 is a schematic configuration diagram showing an exhaust heat recovery system to which the smoke tube boiler of the first embodiment is applied, and FIG. 2 is a schematic plan view showing an exhaust gas introduction chamber of the smoke tube boiler.

  In the first embodiment, as shown in FIG. 1, the exhaust heat recovery system 10 is used by being mounted on a ship or the like, and a plurality (three in this embodiment) of diesel engines (combustors). 11, 12, 13, smoke tube boiler 21, exhaust gas introduction pipes 31, 32, 33 for supplying exhaust gas from diesel engines 11, 12, 13 to the smoke tube boiler 21, and exhaust gas introduction pipes 31, 32, 33 Denitration catalysts 41, 42, 43, exhaust gas exhaust pipes 51, 52, 53 for exhausting exhaust gas from the smoke tube boiler 21, and silencers (silencers) 61, 62, 63 provided in the exhaust gas exhaust pipes 51, 52, 53 It consists of and.

  As shown in FIGS. 1 and 2, the smoke tube boiler 21 includes a water chamber 101, an exhaust gas introduction chamber 102, an exhaust gas discharge chamber 103, and an exhaust gas smoke tube group 104.

  The water chamber 101 has a hollow box-like cylindrical shape and is filled with water. The water chamber 101 is provided with a water supply part 111 at the lower part of the outer peripheral part and a drainage part (steam discharge part) 112 at the upper part of the outer peripheral part.

  The exhaust gas introduction chamber 102 is provided in the lower part (one side) of the water chamber 101. The exhaust gas introduction chamber 102 includes a plurality (three in the present embodiment) of divided exhaust gas introduction chambers 121, 122, and 123. The divided exhaust gas introduction chambers 121, 122, and 123 are separated from each other by a predetermined distance. Is provided.

  Each of the divided exhaust gas introduction chambers 121, 122, 123 has a hollow box-like columnar shape, an upper portion (one end portion) is fixed to the lower portion of the water chamber 101, and an exhaust gas introduction portion 121a, 122a is formed at the lower portion (the other end portion). , 123a are provided. The three divided exhaust gas introduction chambers 121, 122, and 123 have substantially the same shape and are formed to have substantially the same dimensions. The divided exhaust gas introduction chambers 121, 122, 123 are arranged at substantially equal intervals so as to form an equilateral triangle in the lower part of the water chamber 101, and a gap S is formed between the adjacent divided exhaust gas introduction chambers 121, 122, 123. Is provided. In addition, arrangement | positioning of the division | segmentation waste gas introduction chamber 121,122,123 in FIG. 1 is described typically.

  The exhaust gas discharge chamber 103 is provided in the upper part (the other side) of the water chamber 101. The exhaust gas discharge chamber 103 is composed of a plurality (three in this embodiment) of divided exhaust gas introduction chambers 131, 132, and 133.

  The divided exhaust gas discharge chambers 131, 132, 133 are partitioned into a hollow box shape by the partition walls 134, 135, the lower part (one end part) is fixed to the upper part of the water chamber 101, and the upper part (the other end part) has the exhaust gas. Discharge portions 131a, 132a, and 133a are provided. In this case, for example, by arranging two partition walls 134 and 135 in parallel at a predetermined interval in the exhaust gas discharge chamber 103 having a hollow box-shaped columnar shape, the divided exhaust gas discharge chambers 131 arranged in series are arranged. , 132, 133 are formed. Further, the divided exhaust gas discharge chambers 131, 132, and 133 having a fan shape may be formed by radially arranging partition walls in the exhaust gas discharge chamber 103 having a hollow box-shaped columnar shape. Similarly to the exhaust gas introduction chamber 102, a plurality of divided exhaust gas discharge chambers 131, 132, 133 may be provided apart from each other. In this case, the gap between the divided exhaust gas discharge chambers 131, 132, 133 is formed smaller than the gap S between the divided exhaust gas introduction chambers 121, 122, 123.

  The flue gas group 104 includes three divided flue gas groups 141, 142, and 143 corresponding to the divided exhaust gas introduction chambers 121, 122, and 123 and the divided exhaust gas discharge chambers 131, 132, and 133. The divided exhaust gas flue tube groups 141, 142, and 143 pass through the water chamber 101 through the divided exhaust gas introduction chambers 121, 122, and 123 of the exhaust gas introduction chamber 102 and the divided exhaust gas discharge chambers 131, 132, and 133 of the exhaust gas discharge chamber 103. The plurality of smoke pipes 141a, 142a, 143a communicate with each other.

  Here, the operation of the exhaust heat recovery system 10 of the first embodiment will be described.

  In the exhaust heat recovery system 10 of the first embodiment, as shown in FIG. 1, the exhaust gas discharged from each diesel engine 11, 12, 13 passes through the exhaust gas introduction pipes 31, 32, 33, respectively, and the denitration catalyst 41. , 42, 43, the denitration treatment is performed, and then introduced into the smoke tube boiler 21. In the flue-tube boiler 21, exhaust gas is individually introduced into the divided exhaust gas introduction chambers 121, 122, and 123, flows through the exhaust gas smoke tube group 104 to the split exhaust gas discharge chambers 131, 132, and 133, and the exhaust gas exhaust pipes 51 and 52. , 53.

  On the other hand, water is supplied into the water chamber 101 from the water supply unit 111 and exchanges heat with the exhaust gas flowing in the plurality of smoke tubes 141a, 142a, 143a constituting the exhaust gas smoke tube group 104. That is, water is heated by the exhaust gas to generate steam. In this case, the water chamber 101 can discharge only the steam generated from the drainage part 112 when a space part is provided in the upper part of the interior. The two-phase flow is discharged, and the steam is separated by a steam / water separator (not shown).

  At this time, the divided exhaust gas introduction chambers 121, 122, 123 are thermally deformed so that the exhaust gas is introduced from the lower part, the temperature rises in order from the lower part to the upper part, and the lower part spreads outward with respect to the upper part. . However, since each divided exhaust gas introduction chamber 121, 122, 123 is configured individually, the lower portion is uniformly thermally deformed to the outside, and the upper end portion of the side wall on the connection portion side with the water chamber 101 is formed. Local stress is not concentrated and breakage is prevented. Further, since the divided exhaust gas introduction chambers 121, 122, and 123 are individually configured, each of the plurality of diesel engines 11, 12, and 13 can be used even when one diesel engine is not used. Since the divided exhaust gas introduction chambers 121, 122, and 123 are individually thermally deformed, local stress is not concentrated, and damage is prevented.

  In addition, the smoke pipe boiler 21 of this embodiment is not limited to the structure mentioned above. 3 and 4 are schematic plan views illustrating modifications of the exhaust gas introduction chamber of the smoke tube boiler.

As shown in FIG. 3, the exhaust gas introduction chamber 201 is provided below the water chamber 101. The exhaust gas introduction chamber 201 is composed of a plurality (three in this embodiment) of divided exhaust gas introduction chambers 202, 203, and 204 that are spaced apart from each other by a predetermined distance. The divided exhaust gas introduction chambers 202, 203, and 204 have a hollow box-shaped square column shape, and the upper portion is fixed to the lower portion of the water chamber 101. And the adjacent division | segmentation waste gas introduction chambers 202, 203, and 204 are provided with the clearance S between them. The three divided exhaust gas introduction chambers 202, 203, and 204 are formed in different dimensions according to the exhaust amount of the diesel engines 11, 12, and 13. Therefore, by making the divided exhaust gas introduction chambers 202, 203, and 204 into a rectangular tube shape, they can be arranged close to each other, and the divided exhaust gas introduction chambers 202, 203, and 204 can be efficiently arranged.

  As shown in FIG. 4, the exhaust gas introduction chamber 211 is provided in the lower part of the water chamber 101. The exhaust gas introduction chamber 211 is composed of a plurality (three in this embodiment) of divided exhaust gas introduction chambers 212, 213, and 214 that are provided apart from each other by a predetermined distance. Each of the divided exhaust gas introduction chambers 212, 213, and 214 has a box shape in which a hollow cylinder is divided into three in series, and the upper portion is fixed to the lower portion of the water chamber 101. The adjacent divided exhaust gas introduction chambers 212, 213, and 214 are provided with a gap S therebetween. Therefore, a plurality of divided exhaust gas introduction chambers 212, 213, and 214 can be efficiently arranged with respect to the water chamber 101 having a cylindrical shape.

  Thus, in the smoke tube boiler of the first embodiment, the water chamber 101, the exhaust gas introduction chamber 102 provided in one of the water chambers 101, the exhaust gas discharge chamber 103 provided in the other of the water chambers 101, and the exhaust gas An exhaust gas smoke tube group 104 including a plurality of smoke tubes 141a, 142a, and 143a communicating with the introduction chamber 102 and the exhaust gas discharge chamber 103 through the water chamber 101 is provided, and the exhaust gas introduction chamber 102 is separated from each other by a predetermined distance. A plurality of divided exhaust gas introduction chambers 121, 122, and 123 are provided.

  Therefore, when the exhaust gas is introduced into each of the divided exhaust gas introduction chambers 121, 122, and 123 from the lower part at the time of starting the boiler, the temperature of the divided exhaust gas introduction chambers 121, 122, and 123 increases in order from the lower part. And since each division | segmentation waste gas introduction chamber 121,122,123 thermally expands when the temperature of a lower part rises, it deform | transforms so that a lower part may spread outside with respect to an upper part. At this time, since each of the divided exhaust gas introduction chambers 121, 122, and 123 is individually configured, the lower portion is uniformly thermally deformed, and stress is not concentrated on the connection portion with the water chamber 101. As a result, it is possible to suppress the occurrence of local thermal stress on the exhaust gas introduction chamber 102 when the boiler is started.

  Moreover, when some diesel engines 11, 12, and 13 are stopped among several diesel engines 11, 12, and 13 by troubles, such as an exhaust system, the division | segmentation waste gas corresponding to the stopped diesel engines 11, 12, and 13 is stopped. No exhaust gas is introduced into the introduction chambers 121, 122, 123. At this time, since only the divided exhaust gas introduction chambers 121, 122, and 123 into which the exhaust gas is introduced are thermally deformed, local stress is not concentrated, and damage is prevented. Then, when using the exhaust system without any trouble, it is possible to carry out repair work for the exhaust system in which trouble has occurred, and to improve workability.

  In the flue-tube boiler of the first embodiment, the divided exhaust gas introduction chambers 121, 122, and 123 have one end fixed to the water chamber 101 and the other end provided with exhaust gas introduction portions 121a, 122a, and 123a. A gap S between the exhaust gas introduction chambers 121, 122, 123 is provided. Accordingly, the divided exhaust gas introduction chambers 121, 122, and 123 are free at the end on the side where the exhaust gas is introduced, so that the lower portions of the divided exhaust gas introduction chambers 121, 122, and 123 are not constrained at startup. It can be deformed to freely spread outward.

  In the smoke tube boiler according to the first embodiment, the divided exhaust gas introduction chambers 121, 122, and 123 have a hollow box shape, and one end is fixed to the water chamber 101. Therefore, the divided exhaust gas introduction chambers 121, 122, and 123 can be uniformly deformed so that the lower portion extends outward.

  Further, in the exhaust heat recovery system of the first embodiment, a smoke tube boiler 21 and a plurality of diesel engines 11, 12, 13 for supplying exhaust gas to the plurality of divided exhaust gas introduction chambers 121, 122, 123 are provided. Yes. Therefore, it is possible to suppress the occurrence of local thermal stress on the exhaust gas introduction chambers 121, 122, 123 when the boiler is started, and to improve the boiler operating rate.

[Second Embodiment]
FIG. 5 is a schematic configuration diagram illustrating an exhaust heat recovery system to which the smoke pipe boiler according to the second embodiment is applied. In addition, the same code | symbol is attached | subjected to the member which has the same function as embodiment mentioned above, and detailed description is abbreviate | omitted.

  In the second embodiment, as shown in FIG. 5, the exhaust heat recovery system 300 includes a plurality of diesel engines 11, 12, 13, a smoke pipe type composite boiler 301, exhaust gas introduction pipes 31, 32, 33, and a denitration catalyst. 41, 42, 43, exhaust gas exhaust pipes 51, 52, 53, 54, and silencers 61, 62, 63, 64.

  The smoke tube type composite boiler 301 includes a water chamber 101, an exhaust gas introduction chamber 102, an exhaust gas discharge chamber 103, an exhaust gas smoke tube group 104, a furnace 311, a combustion gas discharge chamber 312, and a combustion gas smoke tube group 313. And have. Here, since the water chamber 101, the exhaust gas introduction chamber 102, the exhaust gas discharge chamber 103, and the exhaust gas smoke tube group 104 have the same configuration as in the first embodiment, description thereof will be omitted.

  The furnace 311 is provided in the lower part of the water chamber 101 and is equipped with a burner 314. The combustion gas discharge chamber 312 is provided in the upper part of the water chamber 101, and the combustion gas discharge part 312a is provided. The combustion gas smoke tube group 313 includes a plurality of smoke tubes 313 a that communicate with the furnace 311 and the combustion gas discharge chamber 312 through the water chamber 101.

  Therefore, when the burner 314 is activated, the combustion gas is filled in the furnace 311, and this combustion gas flows through the combustion gas smoke tube group 313 to the combustion gas discharge chamber 312 and is discharged from the exhaust gas discharge pipe 54 to the outside. . On the other hand, the water is supplied into the water chamber 101 from the water supply unit 111, and the exhaust gas flowing through the plurality of smoke pipes 141a, 142a, 143a constituting the exhaust gas smoke pipe group 104 or the plurality of combustion gas smoke pipe groups 313. Heat is exchanged with the combustion gas flowing in the smoke pipe 313a. That is, water is heated by exhaust gas or combustion gas to generate steam. In this case, the burner 314 is stopped while the diesel engines 11, 12, and 13 are driven, and the burner 314 is operated while the diesel engines 11, 12, and 13 are stopped.

  As described above, in the smoke tube boiler according to the second embodiment, in addition to the water chamber 101, the exhaust gas introduction chamber 102, the exhaust gas discharge chamber 103, and the exhaust gas smoke tube group 104, it is provided in one of the water chambers 101. Combustion gas flue gas exhaust pipe comprising a furnace 311, a combustion gas discharge chamber 312 provided on the other side of the water chamber 101, and a plurality of smoke tubes 313 a communicating the furnace 311 and the combustion gas discharge chamber 312 through the water chamber 101. A group 313 is provided.

  Therefore, by providing the furnace 311, the combustion gas discharge 312 chamber, and the exhaust gas smoke tube group 313, it can be applied as a composite boiler, and versatility can be improved.

  In the above-described embodiment, the exhaust gas introduction chamber 102 is divided into the three divided exhaust gas introduction chambers 121, 122, and 123, but the number is not limited to the embodiment. Further, the shape, arrangement, and number of the divided exhaust gas introduction chambers 121, 122, and 123 may be set as appropriate.

  In the above-described embodiment, the boilers 21 and 301 are arranged upright in the vertical direction, but may be arranged in the horizontal direction.

  In the above-described embodiment, the combustor according to the present invention is the diesel engine 11, 13, 13. However, the present invention is not limited to this configuration, and may be a gas turbine combustor.

10,300 Waste heat recovery system 11, 12, 13 Diesel engine 21 Smoke tube boiler 31, 32, 33 Exhaust gas introduction pipe 41, 42, 43 Denitration catalyst 51, 52, 53 Exhaust gas exhaust pipe 61, 62, 63 Silencer (silencer) )
DESCRIPTION OF SYMBOLS 101 Water chamber 102, 201, 211 Exhaust gas introduction chamber 103 Exhaust gas discharge chamber 104 Exhaust gas flue group 121,122,123,202,203,204,212,213,214 Split exhaust gas introduction chamber 131,132,133 Split exhaust gas discharge chamber 141, 142, 143 Divided exhaust gas smoke tube group 301 Smoke tube type composite boiler 311 Furnace 312 Combustion gas discharge chamber 313 Combustion gas smoke tube group 314 Burner S Gap

Claims (5)

A water chamber,
An exhaust gas introduction chamber provided in one of the water chambers;
An exhaust gas discharge chamber provided on the other side of the water chamber;
An exhaust gas smoke tube group comprising a plurality of smoke tubes communicating with the exhaust gas introduction chamber and the exhaust gas discharge chamber through the water chamber;
With
The exhaust gas introduction chamber is composed of a plurality of divided exhaust gas introduction chambers provided apart from each other by a predetermined distance.
A smoke tube boiler characterized by that.   2. The split exhaust gas introduction chamber has one end fixed to the water chamber, the other end provided with an exhaust gas introduction portion, and a gap between adjacent split exhaust gas introduction chambers. The smoke tube boiler described in 1.   3. The flue-tube boiler according to claim 1, wherein the divided exhaust gas introduction chamber has a hollow box shape, and one end thereof is fixed to the water chamber.   Combustion comprising a furnace provided in one of the water chambers, a combustion gas discharge chamber provided in the other of the water chambers, and a plurality of smoke tubes communicating with the furnace and the combustion gas discharge chamber through the water chamber The flue gas boiler according to any one of claims 1 to 3, wherein a flue gas group for gas exhaust gas is provided. A smoke tube boiler according to any one of claims 1 to 4,
A plurality of combustors for supplying exhaust gas to the plurality of split exhaust gas introduction chambers;
An exhaust heat recovery system comprising:

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