Heating structure of exhaust gas treatment unit

Abstract

To provide heating structure of an exhaust gas treatment unit which can properly heat the exhaust gas treatment unit, and can be easily constructed and maintained.SOLUTION: Heating structure 50 heats an exhaust gas treatment unit 30 by using a heated fluid F which is generated by a heated fluid generation unit 80. Therefore, the heating structure 50 can heat the exhaust gas treatment unit 30 without using a member which is difficult in construction and maintenance like an electric heater 101. That is, trouble due to the electric heater 101 which has been explained in a comparison example does not occur since the heating structure 50 uses the heated fluid without using the electric heater 101 for heating. Also, the heated fluid generation unit 80 is equipment generating the heated fluid in a ship 100 at timing at which at least a main engine 16 is operated. Therefore, as far as the timing is one at which an exhaust gas G is discharged from the main engine 16, the heating structure 50 can heat the exhaust gas treatment unit by using the heated fluid at any time.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a heating structure for an exhaust gas treatment unit. [Background technology]

[0002] Conventionally, a heating structure for heating an exhaust gas treatment unit of a ship is known, as described in Patent Document 1. The exhaust gas treatment unit treats exhaust gas from the engine with a reducing agent, etc. In contrast, the heating structure heats the engine exhaust gas at a predetermined timing using exhaust gas from a boiler. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Special Publication No. 2018-508704 Summary of the Invention [Problem to be solved by the invention]

[0004] Here, the heating structure described in the above-mentioned Patent Document 1 uses exhaust gas from a boiler as a heating fluid. However, the timing at which the boiler described in Patent Document 1 generates the heating fluid does not necessarily coincide with the timing at which the exhaust gas treatment unit heats up, and there are cases in which appropriate heating cannot be performed. On the other hand, as a heating structure for heating the exhaust gas treatment unit at the appropriate timing, a structure in which a heater is wrapped around the exhaust gas treatment unit can be given. However, a heating structure using a heater has a problem in that construction and maintenance are difficult.

[0005] The present invention has been made to solve such problems, and aims to provide a heating structure for an exhaust gas treatment device that can properly heat the exhaust gas treatment device and can be easily installed and maintained. [Means for solving the problem]

[0006] The heating structure for an exhaust gas treatment device according to the present invention is a heating structure for heating an exhaust gas treatment device that treats exhaust gas from an engine of a ship, and the heating structure heats the exhaust gas treatment device with a heating fluid generated in a heating fluid generating unit, and the heating fluid generating unit is an apparatus that generates heating fluid within the ship at least when the engine is operating.

[0007] The heating structure for the exhaust gas treatment unit heats the exhaust gas treatment unit with a heating fluid generated in a heating fluid generating unit. Therefore, the heating structure can heat the exhaust gas treatment unit without using a component such as a heater that is difficult to install and maintain. The heating fluid generating unit is a device that generates a heating fluid in the ship at least when the engine is operating. Therefore, the heating structure can heat the exhaust gas treatment unit with a heating fluid at any time when exhaust gas is being discharged from the engine. As described above, a heating structure for an exhaust gas treatment unit is provided that can appropriately heat the exhaust gas treatment unit and can be easily installed and maintained.

[0008] The heating structure may have an outer shell member that is spaced apart from the outer peripheral surface of the exhaust gas treatment device to form an internal space between the outer shell member and the exhaust gas treatment device, and the exhaust gas treatment device may be heated by circulating a heating fluid through the internal space. In this case, a flow path for the heating fluid can be easily formed by simply providing the outer shell member around the exhaust gas treatment device.

[0009] The heated fluid generating unit may be a generator on the ship. The generator generates electricity and discharges exhaust gas at least when the engine is operating. Therefore, the exhaust gas from the generator can be used as the heated fluid. Also, the generator burns the generator engine almost all the time as an auxiliary machine to generate electricity for air conditioning and the like on the ship. Therefore, unlike the ship's engine (main engine), the generator always runs the generator engine, so that high-temperature exhaust gas can always be supplied to the catalyst.

[0010] The exhaust gas treatment device may have an exhaust gas inlet at one end and an exhaust gas outlet at the other end, and the heating structure may supply a heated fluid from the other end and discharge the heated fluid from the one end. In this case, the temperature of the exhaust gas treatment device is likely to be lower at the other end having the outlet than at the one end having the inlet. Meanwhile, the temperature of the heated fluid is higher at the other end, which is the supply side, than at the one end, which is the discharge side. Therefore, the heating structure can heat the other end, which needs more heating, with the heated fluid at a higher temperature. Effect of the Invention

[0011] According to the present invention, it is possible to provide a heating structure for an exhaust gas treatment unit that can appropriately heat the exhaust gas treatment unit and can easily be installed and maintained. [Brief description of the drawings]

[0012] [Figure 1] 1 is a schematic side view showing a ship equipped with a heating structure for an exhaust gas treatment device according to an embodiment of the present invention. [Diagram 2] FIG. 2 is a side view of the exhaust gas treatment unit and the heating structure. [Diagram 3] FIG. 4 is a top view of the exhaust gas treatment unit and the heating structure. [Figure 4] FIG. 11 is a side view showing a heating structure according to a comparative example. [Diagram 5] 4A to 4C are cross-sectional views of heating structures according to an embodiment and a comparative example. [Figure 6] FIG. 4 is a conceptual diagram showing an example of a flow path in an internal space. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Hereinafter, preferred embodiments of a ship according to the present invention will be described with reference to the drawings. Fig. 1 is a schematic side view showing a ship equipped with a heating structure for an exhaust gas treatment device according to an embodiment of the present invention. The ship 100 here is a tanker.

[0014] As shown in FIG. 1, in this ship 100, an engine room 1 is provided on the stern side (left side in FIG. 1) in a hull 19, a pump room 2 is provided on the bow side of the engine room 1 (right side in FIG. 1) separated by a bulkhead 4, and a plurality of cargo spaces 3 are provided on the bow side of the pump room 2 separated by a bulkhead 5. A bow section 13 is provided on the bow side of the hull 19, and a cargo space 3 is provided on the stern side of the bow section 13 separated by a bow bulkhead 14. In addition, a plurality of ballast tanks 6 for storing ballast water are provided on the cargo space 3 side of the ship 100. In addition, a stern section 15 is provided on the stern side of the engine room 1. A tank 7 different from the ballast tank 6 is provided below the stern section 15. A deck 10 is provided on the upper side of the hull 19. The ceiling surface of the engine room 1, pump room 2, cargo space 3, and bow section 13 is formed by the deck 10, and the floor side has a double-bottom structure made up of a bottom shell plating 11 that forms the outer hull of a hull 19 and an inner bottom plating 12 provided on the inside of the hull 19 of the bottom shell plating 11, as shown in Fig. 1. The bulkhead 4 extends in the ship's width direction and is provided so as to extend from the bottom shell plating 11 to the deck 10. The bulkhead 5 extends in the ship's width direction and is provided so as to extend from the inner bottom plating 12 to the deck 10.

[0015] A main engine 16 is provided in the engine room 1. The main engine 16 emits exhaust gas during operation. The ship 100 has an SCR (Selective Catalytic Reduction) system 20 to reduce NOx in the exhaust gas. The SCR system 20 processes NOx in the exhaust gas by using ammonia generated from urea as a reducing agent. The SCR system 20 has an exhaust gas treatment unit 30 connected to the main engine 16 via piping. The exhaust gas treatment unit 30 has multiple catalysts therein, and when the exhaust gas passes through these catalysts, NOx is decomposed into nitrogen and water, and the NOx in the exhaust gas is removed. The exhaust gas from which NOx has been removed is then discharged into the atmosphere from a chimney.

[0016] A generator 70 is provided in the engine room 1. The generator 70 is a device that generates electricity inside the ship 100. The generator 70 generates exhaust gas when generating electricity. The exhaust gas from the generator 70 is used as a heating fluid, which will be described later. The generator 70 generates exhaust gas by generating electricity at least when the main engine 16 is operating.

[0017] Next, the exhaust gas treatment unit 30 and the heating structure 50 of the exhaust gas treatment unit 30 will be described with reference to Fig. 2 and Fig. 3. Fig. 2 is a side view of the exhaust gas treatment unit 30 and the heating structure 50. Note that Fig. 2 shows a cross section of the heating structure 50. Fig. 3 is a view of the exhaust gas treatment unit 30 and the heating structure 50 as viewed from above.

[0018] As shown in FIG. 2, the exhaust gas treatment device 30 includes a main body 31, an upper portion 32, an upper pipe portion 33 (inlet portion), a lower portion 34, and a lower pipe portion 36 (outlet portion). The main body 31 is, for example, cylindrical and extending in the vertical direction along a center line CL. The upper portion 32 is, for example, conical and has a smaller diameter from the upper end of the main body 31 upward along the center line CL. The upper pipe portion 33 is a tubular portion that extends from the upper end of the upper portion 32 along the center line CL and opens upward. The lower portion 34, for example, protrudes downward from the lower end of the main body 31 in a dome shape. The lower pipe portion 36 is a tubular member that extends from the lower end of the lower portion 34 along the center line CL and opens downward. The upper pipe portion 33 is connected to a pipe from the main engine 16. The lower pipe portion 36 is connected to the main engine 16. That is, the exhaust gas treatment unit 30 has an upper pipe section 33 at its upper end (one end) as an inlet for the exhaust gas G, and a lower pipe section 36 at its lower end (the other end) as an outlet for the exhaust gas G. With the above-mentioned configuration, the exhaust gas treatment unit 30 has a cylindrical shape extending in the vertical direction as a whole. Note that the exhaust gas treatment unit 30 cannot have a square shape, and has a cylindrical shape, from the viewpoint of ensuring strength against pressure.

[0019] As shown in FIG. 3, various members protrude from the outer peripheral surface 30a of the main body 31 of the exhaust gas treatment device 30. Specifically, a plurality of foot portions 42 are provided at equal intervals in the circumferential direction on the outer peripheral surface 30a of the main body 31. The foot portions 42 are provided at approximately the center position in the up-down direction of the main body 31. As a result, the exhaust gas treatment device 30 is fixed to a surrounding structure via the foot portions 42. Here, the foot portions 42 extend radially in six directions. In addition, a plurality of pipes 43 extend from the outer peripheral surface 30a of the main body 31. Note that, in order to make the configuration easier to understand, the foot portions 42 and the pipes 43 are omitted in FIG. 2. Also, the above-mentioned members protruding from the outer peripheral surface 30a are merely examples.

[0020] Next, a description will be given of the heating structure 50 of the exhaust gas treatment unit 30. As shown in Fig. 2 and Fig. 3, the heating structure 50 includes an outer shell member 51 and a heat insulating member 52.

[0021] The outer shell member 51 is a member that covers the exhaust gas treatment device 30. The outer shell member 51 surrounds the exhaust gas treatment device 30 from all sides. As a material for the outer shell member 51, for example, steel or the like may be adopted.

[0022] Specifically, the outer shell member 51 includes an upper wall portion 61, a lower wall portion 62, and a peripheral wall portion 63. The upper wall portion 61 is a wall portion that covers the exhaust gas treatment device 30 from above. The upper wall portion 61 extends from the upper pipe portion 33 along the upper portion 32. An opening of the upper pipe portion 33 is exposed from a portion of the upper wall portion 61. The lower wall portion 62 extends from the lower pipe portion 36 along the lower portion 34. An opening of the lower pipe portion 36 is exposed from a portion of the lower wall portion 62.

[0023] The peripheral wall portion 63 has a cylindrical shape extending in the up-down direction along the center line CL (see FIG. 3). In addition, in this figure, the peripheral wall portion 63 may have through-holes formed at locations corresponding to the foot portion 42 and the pipe 43, through which the foot portion 42 and the pipe 43 are inserted.

[0024] The inner peripheral surface 63a of the outer shell member 51 is radially spaced away from the outer peripheral surface 30a of the exhaust gas treatment device 30 to form an internal space SP between the outer shell member 51 and the exhaust gas treatment device 30. The internal space SP is also formed between the upper part 32 and the lower part 34 of the exhaust gas treatment device 30 and the outer shell member 51. The size of the internal space SP is not particularly limited, but may be set to a size that allows at least the heating fluid to flow therethrough. This internal space SP is preferably sealed by the outer shell member 51.

[0025] The heating structure 50 heats the exhaust gas treatment unit 30 with the heating fluid F generated in the heating fluid generating unit 80. The heating structure 50 heats the exhaust gas treatment unit 30 by circulating the heating fluid F in the internal space SP. The heating structure 50 supplies the heating fluid F to the internal space SP from the lower end side and discharges the heating fluid F from the upper end side. Specifically, the heating structure 50 includes a supply pipe 81 provided on the lower end side of the peripheral wall portion 63 and a discharge pipe 82 provided on the upper end side of the peripheral wall portion 63. The supply pipe 81 and the discharge pipe 82 penetrate the outer shell member 51 and communicate with the internal space SP (see FIG. 2). As a result, the heating fluid F supplied from the supply pipe 81 flows through the internal space SP to heat the exhaust gas treatment unit 30 and is discharged from the discharge pipe 82.

[0026] The supply pipe 81 is connected to the heated fluid generating unit 80. As a result, the supply pipe 81 supplies the heated fluid F generated in the heated fluid generating unit 80 to the internal space SP. The discharge pipe 82 is connected to an exhaust gas treatment unit (not shown). As a result, the discharge pipe 82 supplies the heated fluid F from the internal space SP to the exhaust gas treatment unit (not shown) and discharges it to the outside.

[0027] There is no particular limitation on the manner in which the heating fluid F is circulated in the internal space SP. The heating structure 50 may have a partition plate provided in the internal space SP, and the partition plate may form a flow path. For example, as shown in FIG. 6(a), the heating structure 50 may have a partition plate 91 arranged so that the heating fluid F spirals in the internal space SP. Alternatively, as shown in FIG. 6(b), the heating structure 50 may have a partition plate 92 arranged so that the heating fluid F meanders in the internal space SP. The partition plate may be omitted. In FIG. 6, each component is shown roughly, and the outer shell member 51 is shown by a virtual line.

[0028] The heated fluid generating unit 80 is a device that generates the heated fluid F in the ship 100 at least when the main engine 16 is operating. The heated fluid generating unit 80 always generates the heated fluid F when the main engine 16 is operating, and also generates the heated fluid F at other times. Specifically, the heated fluid generating unit 80 is the generator 70 (see also FIG. 1) in the ship 100. It should be noted that it is the generator engine of the generator 70 that generates the exhaust gas, which is the heated fluid F. In the following description, when it is described that the generator 70 generates the exhaust gas (heated fluid F), this means that the generator engine generates the exhaust gas. The generator 70 needs to generate electricity to be supplied to the ship 100. Therefore, when the main engine 16 is operating, the generator 70 generates electricity and generates exhaust gas accordingly. The supply pipe 81 takes out the exhaust gas of the generator 70 as the heated fluid F.

[0029] The heat-insulating member 52 is a member that prevents heat from escaping in order to keep the exhaust gas treatment unit 30 at a high temperature. The heat-insulating member 52 is formed by attaching a heat-insulating sheet or the like to the outer surface of the outer shell member 51. The heat-insulating member 52 is attached in all directions to the outer shell member 51. In this way, the heat-insulating member 52 covers the outer shell member 51 and the exhaust gas treatment unit 30 all around and in all directions. As a material for the heat-insulating member 52, for example, rock wool or the like may be used.

[0030] Next, the workability and maintainability of the heating structure 50 according to this embodiment will be described. For comparison, a heating structure 200 according to a comparative example will be described with reference to Figs. 4 and 5(b). As shown in Fig. 4, the heating structure 200 according to the comparative example is configured by directly attaching an electric heater 1010 and a heat-insulating member 52 to the outer circumferential surface 30a of the exhaust gas treatment unit 30. In this configuration, it is necessary to wrap the electric heater 101 directly around the outer circumferential surface 30a of the exhaust gas treatment unit 30 before attaching the heat-insulating member 52. Furthermore, a metal plate 102 may be provided on the outside of the heat-insulating member 52.

[0031] When constructing the heating structure 200 according to the comparative example, the worker needs to install the electric heater 101 so as to be evenly arranged along the cylindrical shape of the outer peripheral surface of the exhaust gas treatment unit 30. In particular, since the exhaust gas treatment unit 30 has structures such as the foot 42 and the piping 43, the worker needs to install the electric heater 101 while taking these structures into consideration. As described above, the installation of the electric heater 101 is difficult, and there are cases where the heater manufacturer has to install the electric heater 101 instead of at the ship 100 site. In addition, when replacing the electric heater 101, it is necessary to replace several meters of the electric heater 101, which is very time-consuming. Then, the worker installs the heat-insulating member 52 after installing the electric heater 101. Furthermore, after installing the heat-insulating member 52, the worker needs to perform the time-consuming task of installing the metal plate 102 on top of it. In this way, the electric heater 101 is covered with the metal plate 102 and the heat-insulating member 52 (see FIG. 5(b)). Therefore, if a problem such as poor insulation occurs in the electric heater 101, it is very difficult to find where the poor insulation occurred. Furthermore, when performing maintenance such as replacement or inspection, the worker must remove the metal plate 102 and the heat-insulating member 52, and when the work is completed, the worker must take the same amount of time to reattach the heat-insulating member 52 and the metal plate 102. Furthermore, increasing the number of systems of the electric heater 101 causes a problem that the control panel becomes correspondingly larger. There is also the problem that there are no suitable insulators for high-temperature specifications.

[0032] In contrast, the heating structure 50 of the exhaust gas treatment unit 30 according to this embodiment heats the exhaust gas treatment unit 30 with the heating fluid F generated in the heating fluid generating unit 80. Therefore, the heating structure 50 can heat the exhaust gas treatment unit 30 without using a member that is difficult to install and maintain, such as the electric heater 101. That is, since the heating structure 50 uses a heating fluid instead of the electric heater 101 for heating, the problems of the electric heater 101 described in the comparative example do not occur.

[0033] Furthermore, the heated fluid generating section 80 is a device that generates heated fluid F inside the ship 100 at least when the main engine 16 is operating. Therefore, the heating structure 50 is capable of heating the exhaust gas treatment section with heated fluid at any time as long as exhaust gas G is being discharged from the main engine 16. As described above, a heating structure for an exhaust gas treatment section is provided that can appropriately heat the exhaust gas treatment section and can be easily installed and maintained.

[0034] The heating structure 50 has an outer shell member 51 that is spaced apart from the outer peripheral surface 30a of the exhaust gas treatment device 30 to form an internal space SP between the exhaust gas treatment device 30 and the outer shell member 51, and heats the exhaust gas treatment device 30 by circulating a heating fluid F through the internal space SP. In this case, a flow path for the heating fluid F can be easily formed by simply providing the outer shell member 51 around the exhaust gas treatment device 30.

[0035] The exhaust gas treatment device 30 is covered with the outer shell member 51. Then, even if the exhaust gas treatment device 30 is hit during transportation, the outer shell member 51 protects the exhaust gas treatment device 30 from impact. For this reason, in the heating structure 50 according to this embodiment, there is no need to provide the metal plate 102 as in the comparative example, and therefore attachment of the metal plate 102 can be omitted. Therefore, the effort of attaching the metal plate 102 can be omitted, improving workability.

[0036] The heated fluid generating section 80 is the generator 70 in the ship 100. The generator 70 generates power and discharges exhaust gas at least when the main engine 16 is operating. Therefore, the exhaust gas from the generator 70 can be used as the heated fluid F. In addition, the generator 70 is constantly burning its generator engine as an auxiliary machine to generate electricity for air conditioning and the like inside the ship. Therefore, unlike the main engine 16 of the ship 100, the generator 70 is always running its generator engine, and therefore can always supply high-temperature exhaust gas to the catalyst.

[0037] The exhaust gas treatment unit 30 has an upper pipe section 33 which is an inlet section of the exhaust gas G at the upper end side, and a lower pipe section 36 which is an outlet section of the exhaust gas G at the lower end side, and the heating structure 50 supplies the heating fluid F from the lower end side and discharges the heating fluid F from the upper end side. In this case, the exhaust gas treatment unit 30 is likely to have a lower temperature at the lower end side having the lower pipe section 36 which is an outlet section, compared to the upper end side having the upper pipe section 33 which is an inlet section. On the other hand, the heating fluid F has a higher temperature at the lower end side which is the supply side, compared to the upper end side which is the discharge side. Therefore, the heating structure 50 can heat the lower end side which is more necessary to be heated with the heating fluid F in a high temperature state. In addition, the generator 70 is located below the exhaust gas treatment unit 30. Therefore, by providing the supply pipe 81 at the lower end side of the exhaust gas treatment unit 30, the supply pipe 81 can be shortened and a simple piping configuration can be achieved.

[0038] The present invention is not limited to the above-described embodiments.

[0039] For example, the detailed shape of the exhaust gas treatment unit 30 is not particularly limited and may be changed as appropriate. Similarly, the detailed shape of the outer shell member 51 is not particularly limited and may be changed as appropriate.

[0040] In the above embodiment, the exhaust gas treatment unit 30 is configured in a vertically-installed arrangement with a central axis extending in the vertical direction. However, the installation posture of the exhaust gas treatment unit 30 is not particularly limited, and the exhaust gas treatment unit 30 may be configured in a horizontally-installed arrangement with a central axis extending in the horizontal direction. In addition, there is no particular limit as to whether the exhaust gas G is supplied from the upper end side or the lower end side of the exhaust gas treatment unit 30.

[0041] In the above-described embodiment, the heating structure 50 uses the internal space SP formed by disposing the outer shell member 51 as the flow path of the heating fluid F. However, the configuration of the flow path of the heating fluid F is not particularly limited. For example, the heating structure may have a pipe wound around the outer peripheral surface of the exhaust gas treatment device 30, and the heating fluid may be caused to flow through the pipe. However, it is easier to construct the internal space SP by forming the outer shell member 51 than by using this configuration.

[0042] In the above-described embodiment, a generator is used as the heated fluid generating unit. However, the heated fluid generating unit is not particularly limited as long as it is a device that generates heated fluid in the ship at least when the engine is operating.

[0043] In one embodiment, the heating structure heats the exhaust gas treatment device 30 by flowing exhaust gas from a boiler in the ship into the internal space SP. In this case, the boiler may be set to operate when the main engine 16 is operating, in addition to when the ship's normal boiler operates. [Explanation of symbols]

[0044] 16... main engine (engine), 30... exhaust gas treatment unit, 50... heating structure, 51... outer shell member, 70... generator, 80... heated fluid generating unit, 100... ship.

Claims

1. A heating structure for heating an exhaust gas treatment device that treats exhaust gas from an engine of a ship, The heating structure heats the exhaust gas treatment device with a heating fluid generated in a heating fluid generating unit, The heated fluid generating unit is a device that generates the heated fluid in the ship at least when the engine is operating, an outer shell member that is spaced apart from an outer peripheral surface of the exhaust gas treatment unit to form an internal space between the outer shell member and the exhaust gas treatment unit, and the exhaust gas treatment unit is heated by circulating the heating fluid through the internal space; The heating structure of the exhaust gas treatment unit, wherein the heating fluid generating unit is a generator in the ship.

2. the exhaust gas treatment unit has an inlet for the exhaust gas at one end and an outlet for the exhaust gas at the other end, The heating structure for an exhaust gas treatment unit according to claim 1 , wherein the heating structure supplies the heated fluid from the other end side and discharges the heated fluid from the one end side.

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