JP6150834B2 - Demister unit and EGR system - Google Patents

Description

  The present invention relates to a demister unit that removes mist from exhaust gas, and an EGR system to which the demister unit is applied.

  Since the exhaust gas discharged from the boiler via the wet exhaust gas treatment device contains mist, it is necessary to remove the mist contained in this exhaust gas. There exist a demister and a mist eliminator as what removes mist contained in exhaust gas, for example, it is indicated in the following patent documents 1. The wet exhaust gas treatment apparatus described in Patent Document 1 introduces exhaust gas from a boiler into a dust removal tower through an inlet flue, and after removing dust in the exhaust gas, the exhaust gas passes through the dust removal tower demister. It removes mist in the exhaust gas.

  Moreover, there exists exhaust gas recirculation (EGR) as what reduces NOx in exhaust gas. This EGR returns a part of the exhaust gas discharged from the combustion chamber of the internal combustion engine to the combustion chamber as a combustion gas. Therefore, the combustion gas has a reduced oxygen concentration, and the combustion temperature is lowered by delaying the combustion speed, which is a reaction between the fuel and oxygen, and the amount of NOx generated can be reduced.

Japanese Patent Laid-Open No. 08-131864

  In the conventional demister, the exhaust gas introduced from the inlet passes through the bent flow path provided in the demister main body, so that the contained mist collides with the wall surface of the bent flow path and is separated. The demister body has a drain pipe connected to the lower part thereof, and mist separated from the exhaust gas is stored in the tank in the lower part through the drain pipe. By the way, the exhaust gas is introduced from the inlet of the demister by suctioning the inside by a blower connected to the outlet. Therefore, the demister has a negative pressure on the outlet side of the demister body. Then, the water in the tank may be sucked from the lower part of the drain pipe and flow backward to the demister body.

  This invention solves the subject mentioned above, and it aims at providing the demister unit and EGR system which aim at the improvement of mist removal efficiency by suppressing the backflow of the water from a drain guide part to a demister main body.

  To achieve the above object, a demister unit of the present invention is connected to a casing provided with an inlet portion and an outlet portion of a fluid, a demister body that removes mist from the fluid in the casing, and a lower portion of the demister body. And a drain guide part that guides the mist separated by the demister body downward, and a sealing part that prevents inflow of fluid from the drain guide part to the demister body. .

Therefore, the fluid introduced into the casing from the inlet portion passes through the demister body, so that the contained mist is removed, and this mist is guided downward from the drain guide portion by its own weight. At this time, since the sealing portion is provided in the drain guiding portion, even if the outlet portion side becomes negative pressure, the fluid introduced into the casing from the inlet portion flows into the demister body through the drain guiding portion. There is no. As a result, it is possible to improve the mist removal efficiency by suppressing the back flow of water from the drain guide part to the demister body.

  In the demister unit of the present invention, the drain guide part is a drain pipe whose base end part is connected to the lower part of the demister body, and the sealing part prevents fluid from flowing in by storing water in the drain pipe. It is characterized by doing.

  Therefore, since the drain guiding part is a drain pipe and the sealing part is sealed by storing water in the drain pipe, the fluid can easily be prevented from flowing into the demister body through the drain pipe with a simple configuration. Can do.

  In the demister unit of the present invention, the sealing portion is a water storage portion provided in the drain pipe.

  Therefore, since the water storage part is provided in the drain pipe as the sealing part, the configuration of the sealing part can be simplified.

  In the demister unit of the present invention, the drain pipe includes a straight portion whose upper end portion is connected to the lower portion of the demister body, and a bent portion as the water storage portion that is connected to the lower end portion of the straight portion and bends upward. It is characterized by having.

  Therefore, by providing the bent portion as the water storage portion, it is possible to easily prevent the fluid from flowing back to the demister body with a simple configuration.

  In the demister unit of the present invention, a drain discharge pipe for discharging the drain in the casing downward and a water storage tank for storing the drain discharged from the drain discharge pipe are provided, and the drain pipe is the drain discharge pipe. It is connected to.

  Therefore, by connecting the drain pipe to the drain discharge pipe, the mist separated from the exhaust gas flows directly to the drain discharge pipe, and the piping to the water storage tank can be reduced.

  In the demister unit of the present invention, the drain pipe is characterized in that the sealing portion is disposed outside the casing.

  Therefore, when the sealing portion of the drain pipe is disposed outside the casing, the foreign matter can be easily removed when the sealing portion is blocked by the foreign matter, and the maintainability can be improved.

  In the demister unit of the present invention, a drain discharge pipe for discharging the drain in the casing downward and a water storage tank for storing the drain discharged from the drain discharge pipe are provided, and the drain pipe is disposed in the casing. It is characterized by being opened.

  Therefore, by opening the drain pipe in the casing, the drain pipe can be reduced in size, and the manufacturing cost can be reduced.

  In the demister unit of the present invention, the sealing portion is a water storage portion provided in the casing, and a tip end portion of the drain pipe is communicated with the water storage portion.

Therefore, the drain pipe can be sealed without changing the shape of the drain pipe by communicating the tip of the drain pipe with the water storage part of the casing, and the configuration can be simplified and the cost can be reduced. it can.

  In the demister unit of the present invention, a drain discharge pipe for discharging the drain in the casing downward and a water storage tank for storing the drain discharged from the drain discharge pipe are provided, and an upper end portion of the drain discharge pipe is provided in the upper part of the drain discharge pipe. The water storage part is provided by opening upward from the bottom part of the casing.

  Therefore, the water storage part is constituted by opening the upper end part of the drain discharge pipe above the bottom part of the casing, the water storage part can be easily formed in the casing, and the configuration can be simplified.

  In the demister unit of the present invention, a drain discharge pipe for discharging the drain in the casing downward and a water storage tank for storing the drain discharged from the drain discharge pipe are provided, and a partition plate is fixed to the bottom of the casing Thus, the water storage section is provided.

  Therefore, by fixing the partition plate to the bottom of the casing and providing the water storage part, the water storage part can be easily formed in the casing, and the configuration can be simplified.

  In the demister unit of the present invention, the partition plate is characterized in that a discharge hole is formed in a lower end portion.

  Therefore, the foreign matter accumulated in the water storage part can be easily discharged from the discharge hole.

  The demister unit according to the present invention is characterized in that a communication pipe that communicates the outlet portion of the casing and the upper portion of the water storage tank is provided.

  Accordingly, the outlet portion in the casing becomes negative pressure because of the suction force of the blower, and this negative pressure acts on the upper part of the water storage tank through the communication pipe, so that the mist separated from the exhaust gas in the casing is drained. It can be properly discharged from the pipe to the water storage tank.

  Further, the EGR system of the present invention includes an exhaust gas recirculation line that recirculates a part of exhaust gas discharged from the engine as a part of combustion gas to the engine, and water for the exhaust gas flowing through the exhaust gas recirculation line. A scrubber that removes harmful substances by spraying and a demister unit into which exhaust gas discharged from the scrubber is introduced.

  Therefore, when a part of the exhaust gas discharged from the engine passes through the exhaust gas recirculation line, harmful substances are removed by injecting water to the exhaust gas flowing through the exhaust gas recirculation line by the scrubber, and the demister unit After the mist contained therein is removed, it is supplied to the engine. At this time, in the demister unit, the fluid introduced into the casing from the inlet portion passes through the demister main body, so that the contained mist is removed, and the mist is guided downward from the drain guide portion by its own weight. At this time, since the sealing portion is provided in the drain guiding portion, even if the outlet portion side becomes negative pressure, the fluid introduced into the casing from the inlet portion flows into the demister body through the drain guiding portion. There is no. As a result, it is possible to improve the mist removal efficiency by suppressing the back flow of water from the drain guide part to the demister body.

  According to the demister unit and the EGR system of the present invention, it is possible to improve the mist removal efficiency by suppressing the back flow of water from the drain guiding part to the demister body.

FIG. 1 is a schematic diagram showing a diesel engine equipped with an EGR system to which the demister unit of the first embodiment is applied. FIG. 2 is a schematic configuration diagram illustrating the EGR system according to the first embodiment. FIG. 3 is a longitudinal sectional view showing the demister unit of the first embodiment. FIG. 4 is a horizontal sectional view showing the demister unit of the first embodiment. FIG. 5 is a longitudinal sectional view showing an inlet portion of the demister unit of the second embodiment. FIG. 6 is a longitudinal sectional view showing an inlet portion of the demister unit of the third embodiment. FIG. 7 is a side view illustrating a connecting portion between the drain pipe and the drain discharge pipe of the third embodiment. FIG. 8 is a longitudinal sectional view showing the demister unit of the fourth embodiment. FIG. 9 is a longitudinal sectional view showing the demister unit of the fifth embodiment. FIG. 10 is a perspective view showing the partition plate of the fifth embodiment.

  Exemplary embodiments of a demister unit and an EGR 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 diagram showing a diesel engine equipped with an EGR system to which the demister unit of the first embodiment is applied, and FIG. 2 is a schematic configuration diagram showing the EGR system of the first embodiment.

  In the first embodiment, as shown in FIG. 1, the marine diesel engine 10 includes an engine body 11, a supercharger 12, and an EGR system 13.

  As shown in FIG. 2, the engine body 11 is a propulsion engine (main engine) that drives and rotates the propeller for propulsion via a propeller shaft, although not shown. This engine body 11 is a uniflow scavenging exhaust type diesel engine, which is a two-stroke diesel engine, in which the flow of intake and exhaust in the cylinder is unidirectional from the bottom to the top so as to eliminate the residual exhaust. It is. The engine body 11 includes a plurality of cylinders (combustion chambers) 21 in which pistons move up and down, a scavenging trunk 22 that communicates with each cylinder 21, and an exhaust manifold 23 that communicates with each cylinder 21. A scavenging port 24 is provided between each cylinder 21 and the scavenging trunk 22, and an exhaust passage 25 is provided between each cylinder 21 and the exhaust manifold 23. In the engine body 11, the air supply line G <b> 1 is connected to the scavenging trunk 22, and the exhaust line G <b> 2 is connected to the exhaust manifold 23.

  The supercharger 12 is configured by connecting a compressor 31 and a turbine 32 so as to rotate integrally with a rotary shaft 33. In the supercharger 12, the turbine 32 is rotated by the exhaust gas discharged from the exhaust line G2 of the engine body 11, the rotation of the turbine 32 is transmitted by the rotary shaft 33, and the compressor 31 is rotated. / Or the recirculated gas is compressed and supplied to the engine body 11 from the supply air line G1. The compressor 31 is connected to a suction line G6 that sucks air from the outside (atmosphere).

  The supercharger 12 is connected to an exhaust line G3 that discharges exhaust gas that has rotated the turbine 32. The exhaust line G3 is connected to a chimney (funnel) (not shown). An EGR system 13 is provided between the exhaust line G3 and the air supply line G1.

  The EGR system 13 includes exhaust gas recirculation lines G4, G5, and G7, a scrubber 42, a demister unit 14, and an EGR blower (blower) 47. This EGR system 13 mixes a part of the exhaust gas discharged from the marine diesel engine 10 with air, and then compresses it by the supercharger 12 and recirculates it as a combustion gas to the marine diesel engine 10, resulting in combustion. It suppresses the generation of NOx. Here, a part of the exhaust gas is extracted from the downstream side of the turbine 32, but a part of the exhaust gas may be extracted from the upstream side of the turbine 32.

  In the following description, the exhaust gas is exhausted from the engine body 11 to the exhaust line G2, and then exhausted to the outside from the exhaust line G3. The recirculated gas is separated from the exhaust line G3. A part of the exhaust gas is returned to the engine body 11 by the exhaust gas recirculation lines G4, G5, and G7.

  One end of the exhaust gas recirculation line G4 is connected to the middle part of the exhaust line G3. The exhaust gas recirculation line G4 is provided with an EGR inlet valve (open / close valve) 41A, and the other end is connected to the scrubber 42. The EGR inlet valve 41A opens and closes the exhaust gas recirculation line G4 to turn ON / OFF the exhaust gas that is diverted from the exhaust line G3 to the exhaust gas recirculation line G4. The flow rate of exhaust gas passing through the exhaust gas recirculation line G4 may be adjusted by using the EGR inlet valve 41A as a flow rate adjustment valve.

  The scrubber 42 is a venturi-type scrubber, and includes a throat portion 43 having a hollow shape, a venturi portion 44 into which exhaust gas is introduced, and an enlarged portion 45 that gradually returns to the original flow velocity. The scrubber 42 includes a water injection unit 46 that injects water to the exhaust gas introduced into the venturi unit 44. The scrubber 42 is connected to an exhaust gas recirculation line G5 that discharges exhaust gas from which harmful substances such as particulate matter (PM) such as SOx and dust are removed and waste water containing the harmful substances. In addition, in this embodiment, although the venturi type is employ | adopted as a scrubber, it is not limited to this structure.

  The exhaust gas recirculation line G5 is provided with a demister unit 14 and an EGR blower 47.

  The demister unit 14 separates exhaust gas from which harmful substances have been removed by water jet and waste water. The demister unit 14 is provided with a drainage circulation line W <b> 1 that circulates drainage to the water injection unit 46 of the scrubber 42. The drainage circulation line W1 is provided with a hold tank 49 and a pump 50 for temporarily storing drainage.

  The EGR blower 47 guides the exhaust gas in the scrubber 42 from the exhaust gas recirculation line G5 to the demister unit 14.

The exhaust gas recirculation line G7 has one end connected to the EGR blower 47 and the other end connected to the compressor 31 via a mixer (not shown). The exhaust gas is sent to the compressor 31 by the EGR blower 47. The exhaust gas recirculation line G7 is provided with an EGR outlet valve (open / close valve or flow rate adjusting valve) 41B. Air from the suction line G6 and exhaust gas (recirculation gas) from the exhaust gas recirculation line G7 are mixed in a mixer to generate combustion gas. This mixer may be provided separately from the silencer, or the silencer may be configured to add a function of mixing exhaust gas and air without separately providing a mixer. The supercharger 12 can supply the combustion gas compressed by the compressor 31 from the supply line G1 to the engine main body 11, and an air cooler (cooler) 48 is provided in the supply line G1. The air cooler 48 cools the combustion gas by exchanging heat between the combustion gas compressed by the compressor 31 and having a high temperature and the cooling water.

  As shown in FIGS. 3 and 4, the demister unit 14 described above includes a casing 51, a demister main body 52, a drain pipe (drain guide portion) 53, a drain discharge pipe 54, and a water storage tank 55. .

  The casing 51 has a hollow rectangular shape and is configured as a container that forms an internal space. That is, the casing 51 is formed in a box shape by the upstream side wall part 51a, the downstream side wall part 51b, the left and right side wall parts 51c, the ceiling part 51d, and the bottom part 51e. The casing 51 is formed with an inlet 61 into which exhaust gas (solid arrow) and drainage (dotted arrow) are introduced above one end (right end in FIGS. 3 and 4), while the other end. On the upper side of (the left end portion in FIGS. 3 and 4), an outlet portion 62 through which exhaust gas is discharged is formed. And the inlet part 61 is formed in the upstream side wall part 51a, and the exit part 62 is formed in the downstream side wall part 51b. The casing 51 is provided on the exhaust gas recirculation line G5.

  The demister main body 52 is disposed in the casing 51 and allows the exhaust gas introduced from the inlet portion 61 to pass therethrough, thereby separating the mist contained in the exhaust gas and guiding the exhaust gas after removing the mist to the outlet portion 62. Is. The demister main body 52 is provided with a flow path (not shown) that is bent a plurality of times so that exhaust gas can pass therethrough, and is configured as a bellows plate-like body as a whole. The casing 51 is an intermediate portion in the vertical direction, and a demister support plate 63 is disposed from the intermediate portion in the exhaust gas flow direction toward the downstream side. The demister support plate 63 is a plate member disposed along the horizontal direction, and has a side portion fixed to the left and right side wall portions 51c and one end portion fixed to the downstream side wall portion 51b. The demister main body 52 is installed on the other end of the demister support plate 63, and the side is in close contact with the left and right side walls 51c and the upper end is in close contact with the ceiling 51d.

In the casing 51, an upstream flow path 64 is provided between the inlet portion 61 and the demister main body 52, and a downstream flow path 65 is provided between the demister main body 52 and the outlet portion 62. Further, the casing 51 is provided with a lower space 66 below the demister support plate 63 so as to communicate with the upstream flow path 64. The demister main body 52 is provided with a drain pipe 53 that guides the mist separated by the demister main body 52 downward. The drain pipe 53 is a straight pipe disposed along the vertical direction, and has an upper end that passes through the demister support plate 63 and is connected to the demister body 52, and a lower end that is on the lower side of the casing 51. The space 66 is opened.

  The casing 51 is provided with a drain discharge pipe 54 for discharging drain (drainage) downward to the outside. The drain discharge pipe 54 is a straight pipe disposed along the vertical direction and penetrates the bottom 51 e of the casing 51. The drain discharge pipe 54 has a lower end connected to the upper part of the water storage tank 55, and can store the drain discharged from the casing 51 in the water storage tank 55. This water storage tank 55 constitutes a part of the water treatment device, and this water treatment device processes the drain water stored in the water storage tank 55.

  The casing 51 is provided with a water reservoir 67 in the lower space 66. The water storage portion 67 is formed by opening the upper end portion of the drain discharge pipe 54 above the bottom portion 51e of the casing 51 at a position having a predetermined height H1. Therefore, in the casing 51, the mist separated from the exhaust gas becomes drain water and accumulates in the water storage section 67, and the drain water level WF is formed. When the drain water level WF reaches the upper end of the drain discharge pipe 54, the drain water flows from the opening at the upper end of the drain discharge pipe 54 to the inside and is discharged to the water storage tank 55.

By the way, since the downstream flow path 65 in the demister main body 52 is connected to the EGR blower 47 (see FIG. 2) via the exhaust gas recirculation line G5, a negative pressure is generated by the suction force of the EGR blower 47. Then, the exhaust gas introduced into the upstream flow path 64 from the inlet 61 may be sucked from the lower portion of the drain pipe 53 without flowing to the demister main body 52 side and may flow backward to the demister main body 52. Therefore, a sealing portion is provided that prevents the backflow (inflow) of exhaust gas from the drain pipe 53 to the demister body 52.

  This sealing part prevents the backflow of exhaust gas by storing water in the drain pipe 53, and the water storage part 67 provided in the casing 51 functions. That is, as described above, the drain discharge pipe 54 has an opening at the upper end provided at a position having a predetermined height H1 from the bottom 51e of the casing 51, and the drain pipe 53 has an opening at the lower end at the bottom of the casing 51. 51e is provided at a position of a predetermined height H2 lower than the predetermined height H1. Therefore, the drain pipe 53 communicates with the drain water accumulated in the water storage section 67 at the lower portion, and enters the maximum height H (H = H1-H2).

Further, the downstream side flow path 65 in the casing 51 and the upper part (space part) of the water storage tank 55 are communicated by a communication pipe 68. As described above, since the downstream flow path 65 in the demister main body 52 has a negative pressure, the internal pressure of the demister unit 14 and the water storage tank 55 is equalized by causing the communication pipe 68 to function as a pressure equalizing pipe. The communication pipe 68 may communicate the upstream channel 64 and the upper portion of the water storage tank 55. Even in this case, the inside of the demister unit 14 and the water storage tank 55 can be equalized.

  Hereinafter, the operation of the EGR system of the first embodiment will be described.

  As shown in FIG. 2, when combustion gas is supplied from the scavenging trunk 22 into the cylinder 21, the engine main body 11 compresses the combustion gas by a piston, and fuel is supplied to the high-temperature combustion gas. By firing, it ignites spontaneously and burns. The generated combustion gas is discharged as exhaust gas from the exhaust manifold 23 to the exhaust line G2. The exhaust gas discharged from the engine body 11 rotates the turbine 32 in the supercharger 12 and then is discharged to the exhaust line G3. When the EGR inlet valve 41A and the EGR outlet valve 41B are closed, the entire amount is exhausted. It is discharged from G3 to the outside.

  On the other hand, when the EGR inlet valve 41A and the EGR outlet valve 41B are open, part of the exhaust gas flows from the exhaust line G3 to the exhaust gas recirculation line G4. The scrubber 42 removes harmful substances from the exhaust gas (recirculation gas) flowing into the exhaust gas recirculation line G4. That is, when the exhaust gas passes through the venturi section 44 at a high speed, the scrubber 42 cools the exhaust gas by the water injection section 46 and removes harmful substances by dropping with the water. Then, the waste water containing the harmful substance flows into the demister unit 14 together with the EGR gas.

  The exhaust gas from which harmful substances have been removed by the scrubber 42 is discharged to the exhaust gas recirculation line G5, and after the waste water is separated by the demister unit 14, it is sent to the supercharger 12 by the exhaust gas recirculation line G7. The exhaust gas is mixed with the air sucked from the suction line G6 to become a combustion gas, compressed by the compressor 31 of the supercharger 12, and then cooled by the air cooler 48, from the air supply line G1 to the engine body 11. To be supplied.

  Here, processing by the demister unit 14 will be described.

As shown in FIGS. 3 and 4, the exhaust gas introduced from the inlet 61 into the upstream flow path 64 in the casing 51 flows into the demister body 52 on the front, and is a plate having a flow path bent a plurality of times. The mist contained therein adheres to the plate-like body. Then, the mist adhering to the plate-like body of the demister main body 52 flows down due to its own weight and flows into the upper opening of the drain pipe 53 that penetrates the demister support plate 63. The mist that has flowed into the drain pipe 53 flows down into the lower space 66 of the casing 51 through the inside.

  Since the opening of the upper end portion of the drain discharge pipe 54 is located at a predetermined height H1 from the bottom 51e of the casing 51, the mist flowing down from the drain pipe 53 to the lower space 66 of the casing 51 is stored in the casing 51. Stored in the part 67. Further, the exhaust gas introduced into the casing 51 from the inlet portion 61 is accompanied by mist, and drain water by the mist is also stored in the water storage portion 67. When the drain water level WF rises to a predetermined height H <b> 1, the water storage section 67 flows into the drain discharge pipe 54 and is discharged to the water storage tank 55 through the drain discharge pipe 54.

Moreover, when the liquid level WF of the drain water rises to a predetermined height H2, the lower part of the drain pipe 53 is submerged in the drain water accumulated in the water storage part 67, so that the sealing part is formed. Therefore, the exhaust gas introduced into the upstream flow path 64 from the inlet 61 is prevented from being sucked from the lower portion of the drain pipe 53 and flowing back to the demister main body 52. Further, since the downstream side flow path 65 and the water storage tank 55 are communicated with each other through the communication pipe 68, the pressure inside the downstream side flow path 65 and the water storage tank 55 is equalized. Backflow from the lower part of 53 to the demister body 52 is prevented.

  On the other hand, the exhaust gas from which the mist has been removed by the demister body 52 is discharged from the outlet portion 62 through the downstream channel 65.

  As described above, in the demister unit according to the first embodiment, the casing 51 having a hollow shape and provided with the inlet portion 61 and the outlet portion 62 of the exhaust gas, and the demister main body 52 that removes mist from the exhaust gas in the casing 51, A drain pipe (drain guide part) 53 that is connected to the lower part of the demister body 52 and guides the mist separated by the demister body 52 downward, and a water storage part (blocking the exhaust gas from the drain pipe 53 to the demister body 52) Sealing portion) 67 is provided.

  Therefore, the exhaust gas introduced into the casing 51 from the inlet portion 61 passes through the demister main body 52, so that the contained mist is removed, and this mist flows down from the drain pipe 53 due to its own weight. At this time, since the lower end of the drain pipe 53 penetrates into the drain water accumulated in the water storage section 67, the drain water enters here and a sealing section is provided. Therefore, the drain can be appropriately discharged by preventing the inflow of the exhaust gas existing in the upstream flow path 64 to the demister body 52 with a simple configuration.

  In the demister unit of the first embodiment, the drain guide portion is the drain pipe 53, and water is stored in the drain pipe 53 as a sealing portion, thereby preventing the inflow of exhaust gas. Specifically, a water storage part 67 is provided in the casing 51 as a sealing part, and the drain water of the water storage part 67 enters the lower end of the drain pipe 53. Accordingly, it is possible to easily prevent the exhaust gas from flowing into the demister main body 52 through the drain pipe 53 with a simple configuration, thereby simplifying the configuration and reducing the cost.

  In the demister unit of the first embodiment, a drain discharge pipe 54 that discharges the drain in the casing 51 downward, and a water storage tank 55 that stores the drain discharged from the drain discharge pipe 54 are provided, and the upper end of the drain discharge pipe 54 is provided. The water storage part 67 is provided by opening the part above the bottom part 51 e of the casing 51. Therefore, by forming the water storage part 67 in the casing 51, the sealing part can be easily formed, and the configuration can be simplified.

In the demister unit of the first embodiment, a communication pipe 68 that communicates the outlet 62 in the casing 51 and the upper part of the water storage tank 55 is provided. Accordingly, the outlet portion 62 in the casing 51 has a negative pressure because the suction force of the EGR blower 47 acts, and this negative pressure acts on the water storage tank 55 through the communication pipe 68. The tank 55 is equalized, and the mist separated from the exhaust gas in the casing 51 can be properly discharged from the drain drain pipe 54 to the water storage tank 55. Further, by providing the communication pipe 68, the inner diameter of the drain pipe 54 can be reduced, and the head difference between the demister body 52 and the water storage tank 55 can be reduced, and the apparatus can be made compact.

  In the EGR system of the first embodiment, the exhaust gas recirculation line G4 for recirculating a part of the exhaust gas discharged from the engine body 11 to the engine body 11 as a part of the combustion gas, and the exhaust gas recirculation A scrubber 42 that removes harmful substances by injecting water into the exhaust gas flowing through the line G4 and a demister unit 14 into which the exhaust gas discharged from the scrubber 42 is introduced are provided.

  Therefore, when a part of the exhaust gas discharged from the engine body 11 passes through the exhaust gas recirculation line G4, harmful substances are generated by water being injected by the scrubber 42 to the exhaust gas flowing through the exhaust gas recirculation line G4. After being removed and the mist contained by the demister unit 14 being removed, the mist is supplied to the engine body 11. At this time, in the demister unit 14, the exhaust gas passes through the demister main body 52, so that the contained mist is removed and flows down from the drain pipe 53. At this time, since the lower end of the drain pipe 53 penetrates into the drain water accumulated in the water storage section 67, the drain water enters here and a sealing section is provided. Therefore, the exhaust gas introduced into the casing 51 from the inlet 61 does not flow back to the demister body 52 through the drain pipe 53. As a result, the backflow of drain water from the drain pipe 53 to the demister main body 52 can be suppressed to improve the mist removal efficiency.

[Second Embodiment]
FIG. 5 is a longitudinal sectional view showing an inlet portion of the demister unit of the second embodiment. In addition, the same code | symbol is attached | subjected to the member provided with the function similar to embodiment mentioned above, and detailed description is abbreviate | omitted.

  In the second embodiment, as shown in FIG. 5, the demister unit 70 includes a casing 51, a demister main body 52, a drain pipe (drain guide part) 71, a drain discharge pipe 72, and a water storage tank 55. Yes.

  The casing 51 has an inlet portion 61 and an outlet portion 62, and the demister main body 52 is disposed between the inlet portion 61 and the outlet portion 62. The demister body 52 is provided with a drain pipe 71 that guides the mist separated by the demister body 52 downward. The drain pipe 71 includes a straight portion 81, a first bent portion 82, and a second bent portion 83. The straight portion 81 is a straight tube disposed along the vertical direction, and an upper end portion thereof is connected to the demister main body 52 through the demister support plate 63. The first bent portion 82 is a curved tube having a U-shape in a front view bent upward, and one end portion thereof is connected to the lower end portion of the linear portion 81. The second bent portion 83 is a curved tube having a reverse U-shape when viewed from the front, and has one end connected to the other end of the first bent portion 82 and the other end being a lower space. An opening is made upward with respect to the portion 66.

  The drain pipe 71 is not limited to the one constituted by the straight portion 81, the first bent portion 82, and the second bent portion 83. For example, the straight portion 81 and the first bent portion 82 may be configured, and in addition to the straight portion 81, the first bent portion 82, and the second bent portion 83, a straight portion, a bent portion, and the like may be added. Alternatively, the straight portion 81 may be eliminated and the first bent portion 82 alone.

  The casing 51 is provided with a drain discharge pipe 72 for discharging the drain to the outside. The drain discharge pipe 72 is a straight pipe disposed along the vertical direction, and has an upper end connected to the bottom 51 e of the casing 51 and a lower end connected to the upper part of the water storage tank 55. The drain discharged from the water can be stored in the water storage tank 55.

  In the casing 51, inclined plates 84 and 85 are fixed to the bottom 51e. The inclined plates 8 and 85 are inclined downward toward the upper end portion of the drain discharge pipe 72 that opens to the bottom 51 e of the casing 51. The inclined plates 84 and 85 guide the drain water flowing into the casing 51 to the drain discharge pipe 72.

  A sealing portion for preventing the backflow (inflow) of the exhaust gas from the drain pipe 71 to the demister main body 52 is provided. The sealing portion is a first bent portion 82 as a water storage portion provided in the drain pipe 71, and opens to the lower space portion 66 through the second bent portion 83. Here, the bent portion as the sealing portion is a first bent portion 82 having a U-shape when viewed from the front, and a first bent portion 82 and a second bent portion 83 having an S-shape when viewed from the front. is there.

  Therefore, the exhaust gas introduced from the inlet 61 into the upstream flow path 64 in the casing 51 flows into the demister main body 52 at the front and is included by colliding with the plate-like body of the flow path bent a plurality of times. Mist adheres to this plate-like body. Then, the mist adhering to the plate-like body of the demister body 52 flows down due to its own weight and flows into the upper opening of the drain pipe 71 that penetrates the demister support plate 63. Then, the mist that has flowed into the drain pipe 71 flows down into the lower space 66 of the casing 51 through the inside.

  Since the drain pipe 71 is composed of the straight portion 81, the first bent portion 82, and the second bent portion 83, the mist flowing into the drain pipe 71 reaches the first bent portion 82 from the straight portion 81, After temporarily accumulating in the first bent portion 82, it is pushed out to the second bent portion 83 and flows down to the lower space portion 66 of the casing 51. The drain water that has flowed down from the drain pipe 71 into the casing 51 flows into the drain discharge pipe 54 through the inclined plates 84 and 85, and is discharged to the water storage tank 55 through the drain discharge pipe 54.

Further, the drain pipe 71 is formed with a sealing portion by collecting drain water in the first bent portion 82. Therefore, it is possible to prevent the exhaust gas introduced from the inlet 61 into the upstream flow path 64 from being sucked from the lower part of the drain pipe 71 and flowing back to the demister main body 52. Further, since the downstream side flow path 65 and the water storage tank 55 are communicated with each other through the communication pipe 68, the pressure inside the downstream side flow path 65 and the water storage tank 55 is equalized. Backflow from the lower part of 71 to the demister body 52 is prevented.

  On the other hand, the exhaust gas from which the mist has been removed by the demister body 52 is discharged from the outlet portion 62 through the downstream channel 65.

  As described above, in the demister unit according to the second embodiment, the drain pipe (drain guide part) 71 is connected to the lower part of the demister body 52 and guides the mist separated by the demister body 52 downward, and the drain pipe 71. A first bent portion 82 is provided as a water storage portion (sealing portion) that prevents the exhaust gas from flowing into the demister body 52.

Therefore, the exhaust gas introduced into the casing 51 from the inlet portion 61 passes through the demister main body 52, whereby the contained mist is removed, and this mist flows down from the drain pipe 71 by its own weight. At this time, the drain pipe 71 is provided with a sealing portion by collecting drain water in the first bent portion 82. Therefore, the exhaust gas introduced into the casing 51 from the inlet 61 does not flow backward to the demister body 52 through the drain pipe 71. As a result, the backflow of drain water from the drain pipe 71 to the demister main body 52 can be suppressed and mist removal efficiency can be improved.

  Further, by forming the first bent portion 82 in the drain pipe 71, a sealing portion for collecting drain water is provided, and it is only necessary to change the shape of the drain pipe 71, without changing the casing 51, The overall configuration can be simplified.

  In the demister unit of the second embodiment, the drain pipe 71 includes a straight part 81 whose upper end is connected to the lower part of the demister body 52 and a first bent part 82 that is connected to the lower end of the straight part 81 and bends upward. And consists of Therefore, the first bent portion 82 can discharge drain appropriately by preventing inflow of exhaust gas existing in the upstream flow path 64 to the demister body 52 with a simple configuration.

  In the demister unit of the second embodiment, the drain pipe 71 is opened in the casing 51. Therefore, the drain pipe 71 can be reduced in size, and the manufacturing cost can be reduced.

[Third Embodiment]
FIG. 6 is a longitudinal sectional view showing an inlet portion of the demister unit of the third embodiment, and FIG. 7 is a side view showing a connecting portion between the drain pipe and the drain discharge pipe. In addition, the same code | symbol is attached | subjected to the member provided with the function similar to embodiment mentioned above, and detailed description is abbreviate | omitted.

  In the third embodiment, as shown in FIGS. 6 and 7, the demister unit 90 includes a casing 51, a demister main body 52, a drain pipe (drain guide portion) 91, a drain discharge pipe 72, and a water storage tank 55. It has.

  The casing 51 has an inlet portion 61 and an outlet portion 62, and the demister main body 52 is disposed between the inlet portion 61 and the outlet portion 62. The demister body 52 is provided with a drain pipe 91 that guides the mist separated by the demister body 52 downward. The drain pipe 91 includes a straight portion 101, a first bent portion 102, a second bent portion 103, and a third bent portion 104.

  The straight portion 101 is a straight pipe disposed along the vertical direction, and is disposed in the lower space portion 66 of the casing 51, and the upper end portion passes through the demister support plate 63 and is connected to the demister main body 52. The lower end portion is opened and connected to the bottom portion 51e of the casing 51. The first, second, and third bent portions 102, 103, and 104 are disposed on the outer side below the casing 51. The first bent portion 102 is a curved tube that is bent upward and has a U-shape when viewed from the front, and has one end connected to the lower end of the straight portion 101. The second bent portion 103 is a curved tube having a reverse U-shape when viewed from the front, and has one end connected to the other end of the first bent portion 102. The third bent portion 104 is a curved tube that bends at 90 degrees, and one end thereof is connected to the lower end of the second bent portion 103 via a flange 105.

  The casing 51 is provided with a drain discharge pipe 72 that discharges drain to the outside at the lower part, the upper end part is connected to the bottom part 51 e of the casing 51, and the lower end part is connected to the upper part of the water storage tank 55. In the drain pipe 91, the other end of the third bent portion 104 is connected to a midway portion in the vertical direction.

A sealing portion for preventing the backflow (inflow) of the exhaust gas from the drain pipe 91 to the demister body 52 is provided. This sealing portion is a first bent portion 102 as a water storage portion provided in the drain pipe 91, and communicates with the drain discharge pipe 72 through the second bent portion 103 and the third bent portion 104. Here, the bending part as a sealing part is the 1st bending part 102 which makes a front view U shape.

  Therefore, the exhaust gas introduced from the inlet 61 into the upstream flow path 64 in the casing 51 flows into the demister main body 52 at the front and is included by colliding with the plate-like body of the flow path bent a plurality of times. Mist adheres to this plate-like body. Then, the mist adhering to the plate-like body of the demister main body 52 flows down due to its own weight and flows into the upper opening of the drain pipe 91 that penetrates the demister support plate 63. Then, the mist that has flowed into the drain pipe 91 flows down into the lower space 66 of the casing 51 through the inside.

  Since the drain pipe 91 is composed of the straight portion 101, the first bent portion 102, the second bent portion 103, and the third bent portion 104, the mist that has flowed into the drain pipe 91 is The bent portion 102 is reached, temporarily accumulated in the second bent portion 102, pushed out to the second bent portion 103, and flows into the drain discharge pipe 72 through the third bent portion 104. The drain water that has flowed from the drain pipe 91 into the drain discharge pipe 72 is discharged to the water storage tank 55 through the drain discharge pipe 72.

  Further, the drain pipe 91 has a sealed portion formed by drain water collecting in the first bent portion 102. Therefore, the exhaust gas introduced from the inlet 61 into the upstream flow path 64 is prevented from being sucked from the lower portion of the drain pipe 91 and flowing back to the demister main body 52.

  On the other hand, the exhaust gas from which the mist has been removed by the demister body 52 is discharged from the outlet portion 62 through the downstream channel 65.

  As described above, in the demister unit of the third embodiment, the drain pipe (drain guide portion) 91 that is connected to the lower part of the demister body 52 and guides the mist separated by the demister body 52 downward, and the drain pipe 91 A first bent portion 102 is provided as a water storage portion (sealing portion) that prevents exhaust gas from flowing into the demister body 52.

  Therefore, the exhaust gas introduced into the casing 51 from the inlet portion 61 passes through the demister main body 52 to remove contained mist, and this mist flows down from the drain pipe 91 due to its own weight. At this time, the drain pipe 91 is provided with a sealing portion because drain water accumulates in the first bent portion 102. Therefore, the exhaust gas introduced into the casing 51 from the inlet 61 does not flow back to the demister main body 52 through the drain pipe 91. As a result, the backflow of drain water from the drain pipe 91 to the demister main body 52 can be suppressed and mist removal efficiency can be improved.

  In the demister unit of the third embodiment, the lower end of the drain pipe 91 is connected to the middle part of the drain discharge pipe 72. Therefore, the mist separated from the exhaust gas by the demister main body 52 is caused to flow directly to the drain discharge pipe 72 through the drain pipe 91, and an increase in drain water in the casing 51 can be suppressed.

  In the demister unit of the third embodiment, the drain pipe 91 includes the first bent portion constituting the sealing portion by disposing the first, second, and third bent portions 102, 103, and 104 outside the casing 51. 102 is located outside the casing 51. Therefore, when the first, second, and third bent portions 102, 103, and 104 are blocked by foreign matter, the first, second, and third bent portions 102, 103, and 104 can be removed to remove the foreign matter, Maintainability can be improved.

[Fourth Embodiment]
FIG. 8 is a longitudinal sectional view showing the demister unit of the fourth embodiment. In addition, the same code | symbol is attached | subjected to the member provided with the function similar to embodiment mentioned above, and detailed description is abbreviate | omitted.

  In the fourth embodiment, as shown in FIG. 8, the demister unit 110 includes a casing 51, a demister main body 52, a drain pipe (drain guide part) 111, a drain discharge pipe 72, and a water storage tank 55. Yes.

  The casing 51 has an inlet portion 61 and an outlet portion 62, and the demister main body 52 is disposed between the inlet portion 61 and the outlet portion 62. The demister body 52 is provided with a drain pipe 111 at the bottom for guiding the mist separated by the demister body 52 downward. The drain pipe 111 includes a straight part 121 and a bent part 122.

  The straight portion 121 is a straight pipe disposed along the vertical direction, and is disposed in the lower space portion 66 of the casing 51, and the upper end portion passes through the demister support plate 63 and is connected to the demister main body 52. The lower end portion is opened and connected to the bottom portion 51e of the casing 51. The bent portion 122 is a curved tube having a U shape when viewed from the front, and is disposed outside the casing 51. One end portion of the bent portion 122 is connected to the lower end portion of the linear portion 121, and the other end portion opens to the bottom portion 51 e and is connected to the upstream flow path 64. The casing 51 is provided with a drain discharge pipe 72 that discharges drain to the outside at the lower part, the upper end part is connected to the bottom part 51 e of the casing 51, and the lower end part is connected to the upper part of the water storage tank 55.

  A sealing portion for preventing the backflow (inflow) of the exhaust gas from the drain pipe 111 to the demister main body 52 is provided. This sealing portion is a bent portion 122 as a water storage portion provided in the drain pipe 111. Here, the bending part as a sealing part is the bending part 122 which makes a front view a U shape.

  Therefore, the exhaust gas introduced from the inlet 61 into the upstream flow path 64 in the casing 51 flows into the demister main body 52 at the front and is included by colliding with the plate-like body of the flow path bent a plurality of times. Mist adheres to this plate-like body. Then, the mist adhering to the plate-like body of the demister main body 52 flows down due to its own weight and flows into the upper opening of the drain pipe 111 that penetrates the demister support plate 63. Further, the exhaust gas introduced into the casing 51 from the inlet portion 61 is accompanied by drain water, and this drain water flows into the drain pipe 111 from the upstream channel 64.

  Since the drain pipe 111 is provided with the bent portion 122, the mist flowing into the drain pipe 111 and the drain water flowing into the drain pipe 111 from the upstream channel 64 are temporarily accumulated in the bent portion 122. A sealing part is formed. Thereafter, when the bent portion 122 is filled with drain water, the mist that has flowed into the drain pipe 111 is pushed out to the upstream flow path 64 through the inside. The drain water that has flowed into the upstream flow path 64 from the drain pipe 111 is discharged to the water storage tank 55 through the drain discharge pipe 72.

  Further, the drain tube 111 forms a sealed portion when drain water accumulates in the bent portion 122. Therefore, the exhaust gas introduced into the upstream flow path 64 from the inlet 61 is prevented from being sucked from the drain pipe 111 and flowing back to the demister body 52. Further, since the downstream side passage 65 and the water storage tank 55 are communicated with each other by the communication pipe 68, the pressure inside the downstream side passage 65 and the water storage tank 55 is equalized. Backflow from the lower part to the demister body 52 is prevented.

  On the other hand, the exhaust gas from which the mist has been removed by the demister body 52 is discharged from the outlet portion 62 through the downstream channel 65.

  As described above, in the demister unit according to the fourth embodiment, the drain pipe (drain guide portion) 111 that is connected to the lower part of the demister body 52 and guides the mist separated by the demister body 52 downward, and the drain pipe 111. A bent portion 122 is provided as a water storage portion (sealing portion) that prevents the exhaust gas from flowing into the demister body 52.

  Therefore, the exhaust gas introduced into the casing 51 from the inlet 61 passes through the demister main body 52 to remove contained mist, and this mist flows from the drain pipe 111 to the upstream flow path 64 by its own weight. At this time, the drain pipe 111 is provided with a sealing portion by collecting drain water in the bent portion 122. Therefore, the exhaust gas introduced from the inlet 61 into the upstream flow path 64 is prevented from flowing back to the demister body 52 through the drain pipe 111. As a result, the backflow of drain water from the drain pipe 111 to the demister main body 52 can be suppressed and mist removal efficiency can be improved.

  In the demister unit of the fourth embodiment, the bent portion 122 is provided in the drain pipe 111, and the lower end portion is communicated with the upstream channel 64. Therefore, waste water (dotted arrow) associated with the exhaust gas can be supplied to the bent portion 122 and sealed early.

  In the demister unit of the fourth embodiment, the bent portion 122 of the drain pipe 111 is disposed outside the casing 51. Therefore, when the bent portion 122 is blocked by foreign matter, the bent portion 122 can be removed and the foreign matter can be removed, so that maintainability can be improved.

[Fifth Embodiment]
FIG. 9 is a longitudinal sectional view showing a demister unit of the fifth embodiment, and FIG. 10 is a perspective view showing a partition plate. In addition, the same code | symbol is attached | subjected to the member provided with the function similar to embodiment mentioned above, and detailed description is abbreviate | omitted.

  In the fifth embodiment, as shown in FIGS. 9 and 10, the demister unit 130 includes a casing 51, a demister main body 52, a drain pipe (drain guide portion) 131, a drain discharge pipe 72, and a water storage tank 55. It has.

  The casing 51 has an inlet portion 61 and an outlet portion 62, and the demister main body 52 is disposed between the inlet portion 61 and the outlet portion 62. The demister body 52 is provided with a drain pipe 131 that guides the mist separated by the demister body 52 downward. The drain pipe 131 is a curved pipe bent at about 90 degrees, is disposed in the lower space 66 of the casing 51, and has an upper end that passes through the demister support plate 63 and is connected to the demister body 52. The lower end portion opens to the partition wall portion 123 and is connected to the upstream flow path 64. The casing 51 is provided with a drain discharge pipe 72 that discharges drain to the outside at the lower part, the upper end part is connected to the bottom part 51 e of the casing 51, and the lower end part is connected to the upper part of the water storage tank 55.

  A sealing portion for preventing the backflow (inflow) of the exhaust gas from the drain pipe 131 to the demister main body 52 is provided. In the casing 51, the partition plate 141 is fixed to the upper surface portion of the bottom portion 51 e in the upstream channel 64. The partition plate 141 is arranged so as to be parallel to the partition wall portion 123 at a predetermined interval, and a plurality of discharge holes 142 are formed at the lower end portion. Here, the plurality of discharge holes 142 can discharge foreign matter and drain water. The sealing portion described above is the water storage portion 143 provided by the partition wall portion 123 and the partition plate 141 in the upstream flow path 64 of the casing 51, and the other end portion of the drain pipe 131 passes through the partition wall portion 123 and communicates therewith. doing.

Therefore, the exhaust gas introduced from the inlet 61 into the upstream flow path 64 in the casing 51 flows into the demister main body 52 at the front and is included by colliding with the plate-like body of the flow path bent a plurality of times. Mist adheres to this plate-like body. Then, the mist adhering to the plate-like body of the demister main body 52 flows down due to its own weight and flows into the upper opening of the drain pipe 131 that penetrates the demister support plate 63. And the mist which flowed in in the drain pipe 131 flows into the upstream flow path 64 of the casing 51 through the inside.

  The upstream flow path 64 is provided with a water storage section 143 by a partition plate 141, and the lower end of the drain pipe 131 communicates with the water storage section 143. Therefore, the mist flowing into the drain pipe 131 It flows into 64 water storage parts 143. The drain water flowing from the drain pipe 131 to the water storage unit 143 passes through the plurality of discharge holes 142 or overflows the partition plate 141 and flows into the drain discharge pipe 72, and the water storage tank passes through the drain discharge pipe 72. 55 is discharged.

  In addition, the drain pipe 131 forms a sealed portion when drain water accumulates in the water storage portion 143. Therefore, the exhaust gas introduced into the upstream flow path 64 from the inlet 61 is prevented from being sucked from the drain pipe 131 and flowing back to the demister body 52. Moreover, unburned fuel, oil, and the like are mixed as foreign matter in the drain water of the exhaust gas, and this foreign matter may accumulate in the water storage unit 143 and reduce the storage amount of drain water. However, the foreign matter mixed in the drain water is discharged from the water storage unit 143 through the plurality of discharge holes 142, and the amount of water stored in the water storage unit 143 is not reduced.

  On the other hand, the exhaust gas from which the mist has been removed by the demister body 52 is discharged from the outlet portion 62 through the downstream channel 65.

  As described above, in the demister unit of the fifth embodiment, a drain pipe (drain guide portion) 131 that is connected to the lower portion of the demister main body 52 and guides the mist separated by the demister main body 52 downward is provided. A water storage part (sealing part) 143 is provided by fixing the partition plate 141 on the upper surface of the bottom part 51 e of the water pipe, and the lower end part of the drain pipe 131 communicates with the water storage part 143.

  Therefore, the exhaust gas introduced into the casing 51 from the inlet 61 passes through the demister main body 52 to remove contained mist, and this mist flows from the drain pipe 131 to the water storage unit 143 by its own weight. At this time, the drain pipe 131 is provided with a sealing portion by communicating with drain water having a lower end portion accumulated in the water storage portion. Therefore, the exhaust gas introduced into the casing 51 from the inlet 61 does not flow back to the demister main body 52 through the drain pipe 131. As a result, the backflow of drain water from the drain pipe 131 to the demister main body 52 can be suppressed and mist removal efficiency can be improved.

  In the demister unit of the fifth embodiment, the partition plate 141 is formed with a discharge hole 142 for discharging foreign matter and drain water from the water storage unit 143. Therefore, foreign matter and drain water collected in the water storage unit 143 can be easily discharged from the discharge hole 142.

  In the fourth and fifth embodiments described above, the upstream flow path 64 and the lower space 66 are partitioned by the partition wall 123, but the casing 51 constituting the lower space 66 by the partition wall 123. A part of the lower side of the downstream side wall 51b and a part of the downstream of the bottom 51e may be eliminated. That is, the straight part 121 and the drain pipe 131 of the drain pipe 111 may be arranged outside the casing 51.

  In the above-described embodiment, the drain pipes 53, 71, 91, 111, 131 and the drain drain pipe 54 are described as one, but a plurality of drain pipes may be provided. Further, although the communication pipe 68 that communicates the outlet portion 62 of the casing 51 and the upper part of the water storage tank 55 is provided outside the casing 51, a part of the communication pipe 68 may be disposed in the casing 51.

  Moreover, in embodiment mentioned above, although demonstrated using the main engine as a marine diesel engine, it is applicable also to the diesel engine used as a generator.

DESCRIPTION OF SYMBOLS 10 Marine diesel engine 11 Engine main body 12 Supercharger 13 EGR system 14,70,90,110,130 Demister unit 41A EGR inlet valve 41B EGR outlet valve 42 Scrubber 47 EGR blower 48 Air cooler (cooler)
51 Casing 52 Demister body 53, 71, 91, 111, 131 Drain pipe (drain guiding part)
54,72 Drain discharge pipe 55 Water storage tank 61 Inlet part 62 Outlet part 63 Demister support plate 67,143 Water storage part (sealing part)
68 Communication pipe 81, 121 Straight part 82, 122 First bent part (sealing part, water storage part)
83 Second bent portion 84, 85 Inclined plate 123 Partition wall 141 Partition plate 142 Discharge hole G4, G5, G7 Exhaust gas recirculation line G6 Suction line W1 Drainage circulation line

Claims (13)

A casing provided with a fluid inlet and outlet;
A demister body for removing mist from the fluid in the casing;
A drain guide part that is connected to a lower part of the demister body and guides the mist separated by the demister body downward;
A sealing portion that prevents inflow of fluid from the drain guide portion to the demister body;
A drain discharge pipe for discharging the drain in the casing downward;
A water storage tank for storing drain discharged from the drain discharge pipe;
A communicating pipe that communicates the upper portion of the water storage tank and the downstream-passage downstream of the pre-Symbol demister body that put in the casing,
A demister unit comprising: A casing provided with a fluid inlet and outlet;
A demister body for removing mist from the fluid in the casing;
A drain guide part that is connected to a lower part of the demister body and guides the mist separated by the demister body downward;
A sealing portion that prevents inflow of fluid from the drain guide portion to the demister body;
A drain discharge pipe for discharging the drain in the casing downward;
A water storage tank for storing drain discharged from the drain discharge pipe;
A communication pipe that communicates the upstream flow path provided separately from the drain discharge pipe on the upstream side of the demister body in the casing and the upper portion of the water storage tank;
A demister unit comprising: Wherein said drain leading portion is a drain pipe having a base end portion is connected to a lower portion of the demister body, said sealing portion, characterized in that to prevent the flow of fluid by water in the drain pipe The demister unit according to claim 1 or 2 . The demister unit according to claim 3 , wherein the sealing portion is a water storage portion provided in the drain pipe. The drain pipe includes a straight portion having an upper end portion connected to a lower portion of the demister body, and a bent portion serving as the water storage portion that is connected to the lower end portion of the straight portion and bends upward. The demister unit according to claim 4 . The demister unit according to any one of claims 3 to 5 , wherein the drain pipe is connected to the drain discharge pipe. The demister unit according to claim 6 , wherein the drain pipe has the sealing portion disposed outside the casing. Prior Symbol drain pipe, demister unit according to claims 3 to claims 5, characterized in that the opening in the casing. 4. The demister unit according to claim 3 , wherein the sealing portion is a water storage portion provided in the casing, and a distal end portion of the drain pipe communicates with the water storage portion. Demister unit according to claim 9 in which the upper end of the front Symbol drain discharge pipe, characterized in that the reservoir is provided by opening upward from the bottom of the casing. Demister unit according to claim 9, wherein the reservoir is provided in the partition plate is fixed to the bottom of the front Symbol casing. The demister unit according to claim 11 , wherein the partition plate has a discharge hole at a lower end portion. An exhaust gas recirculation line for recirculating a part of the exhaust gas discharged from the engine to the engine as a part of the combustion gas;
A scrubber that removes harmful substances by injecting water into the exhaust gas flowing through the exhaust gas recirculation line;
The demister unit according to any one of claims 1 to 12 , wherein exhaust gas discharged from the scrubber is introduced,
An EGR system comprising:

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