JP2009090182A - Exhaust gas treating device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a compact exhaust gas treating device, which reduces the load on an internal combustion, and can suppress costs of usage also. <P>SOLUTION: The exhaust gas treating device 5 has a storage part 10 provided so as to extend downward from a horizontal part 4. Water is stored in the storage part 10, and a water surface 6 is provided with a filter member 16. Further, the exhaust gas treating device 5 has a shower member 11. The shower member 11 has an intake part 12 with one end immersed in water inside the storage part 10 and at the same time, with the other end extending upward, and a discharge channel 13 with one end connected to the upper end of the intake part 12 and at the same time, with the other end provided so as to extend horizontally upstream above the water surface 6. Three fountain heads 14 are provided at even intervals along an axial direction of the discharge channel 13 on the lower part surface 13b of the discharge channel 13. Further, the exhaust gas treating device 5 has three skew plates 15 provided beneath each fountain head 14, in total, nine. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an exhaust gas treatment apparatus, and more particularly to a wet exhaust gas treatment apparatus.

As a technique for purifying exhaust gas from an internal combustion engine such as an automobile, a method of reducing NO _x (nitrogen oxide) by a NO _x purification catalyst using a noble metal is generally used. However, the NO _x purification catalyst has a low NO _x purification ability at low temperatures, and therefore it is necessary to increase the amount of noble metal used for the NO _x purification catalyst in order to improve the exhaust purification ability at low temperatures. Thus, increasing the amount of noble metal used does not necessarily provide satisfactory performance, and is not preferable in terms of cost.

To solve this problem, Patent Document 1, the exhaust gas treatment apparatus is disclosed for removing particulate matter (PM) and NO _x in the exhaust gas with water. In this exhaust gas treatment device, water accumulated at the bottom of the exhaust gas treatment device is pumped up by using a swash plate and a weir to cause water to flow down in a waterfall shape from above to below, and by flowing exhaust gas from below to above , contacting the exhaust gas with water, PM and NO _x are removed. Patent Document 2 discloses an exhaust gas treatment device that releases exhaust gas into an alkaline solution to remove NO _x in the exhaust gas. Furthermore, Patent Document 3 discloses an exhaust gas treatment apparatus that dissolves carbon dioxide (CO ₂ ) and NO _x in exhaust gas by bringing the exhaust gas into contact with an acidic liquid and then with an alkaline liquid. Yes.

JP 2003-176713 A Japanese Utility Model Publication No. 5-92410 JP 2006-77603 A

  However, the exhaust gas treatment device of Patent Document 1 has a problem that it becomes a large device due to a structure in which a vertically long main body is provided in a pipe through which exhaust gas flows. The exhaust gas treatment device of Patent Document 2 has a problem in that exhaust gas is directly discharged into an alkaline solution, so that a back pressure is applied and a load is applied to the internal combustion engine. The exhaust gas treatment device of Patent Document 3 requires both an acidic liquid and an alkaline liquid, and has a problem of high usage costs.

  The present invention has been made to solve such a problem, and an object of the present invention is to provide an exhaust gas treatment apparatus that is compact, does not apply a load to an internal combustion engine, and can reduce the use cost.

An exhaust gas treatment apparatus according to the present invention has a horizontal portion extending in the horizontal direction, an exhaust pipe through which exhaust gas flows, a storage portion that extends downward from the horizontal portion and stores water, and one end of the exhaust pipe A water intake part immersed in water and having the other end extending upward, a water discharge part provided with one end connected to the other end of the water intake part and the other end extending above the water, and a lower part of the water discharge part A shower member having at least one fountain port provided on the surface, and a swash plate provided below the fountain port, and the water in the storage unit sequentially flows through the water intake unit and the water discharge unit. The swash plate is ejected from the fountain port toward the swash plate, and the swash plate is provided so as to be inclined downward in the flow direction of the exhaust gas. A storage portion is provided so as to extend downward from the horizontal portion of the exhaust pipe, and since the shower member and the swash plate are accommodated in the horizontal portion and the storage portion, the storage portion has a shape protruding only downward from the horizontal portion. Moreover, since exhaust gas distribute | circulates above the water in a storage part, a back pressure is not applied. Moreover, PM and NO _x in the exhaust gas are removed by water alone.
The horizontal portion may have a shape that becomes narrower in a flow direction of the exhaust gas.
A pump may be further provided, and the pump may send water in the reservoir to the water intake unit and the water discharge unit.
An alkaline substance may be dissolved in the water. Here, the alkaline substance means a substance whose solution exhibits alkalinity when dissolved in water.
An oxidation catalyst may be provided on the swash plate.
The exhaust pipe may be provided with an oxidation catalyst upstream of the horizontal portion.
A filter member may be provided below the swash plate.
The bottom part of the storage part may have a downward slope toward the flow direction of the exhaust gas.
The exhaust pipe may be provided with a cooling device.

A storage portion is provided so as to extend downward from the horizontal portion of the exhaust pipe, and the shower member and the swash plate are accommodated in the horizontal portion and the storage portion, thereby having a shape projecting only downward from the horizontal portion from the outside. Therefore, the exhaust gas treatment device can be made compact. Further, since exhaust gas flows above the water in the reservoir, no back pressure is applied, so that it is possible to prevent the internal combustion engine from being loaded. Further, since the PM and NO _x in the exhaust gas is removed by water alone, it is possible to suppress the use cost.

Embodiments of the present invention will be described below with reference to the accompanying drawings.
Embodiment 1 FIG.
An exhaust gas treatment apparatus according to Embodiment 1 is shown in FIG. The diesel engine 1 that is an internal combustion engine is provided with an exhaust manifold 2 that communicates with a combustion chamber (not shown), and an exhaust pipe 3 is connected to the exhaust manifold 2. The exhaust pipe 3 has a horizontal portion 4 extending in the horizontal direction at least partially. The horizontal portion 4 has a shape that narrows from upstream to downstream, that is, toward the flow direction of exhaust gas in the exhaust pipe 3. An exhaust gas treatment device 5 is provided in the horizontal portion 4.

  The exhaust gas treatment device 5 has a reservoir 10 provided so as to extend downward from the horizontal portion 4. Water is stored in the reservoir 10, and the water surface 6 is lower than the horizontal portion 4. A filter member 16 is provided in the reservoir 10 so as to float on the water surface 6. Further, the exhaust gas treatment device 5 has a shower member 11. The shower member 11 has one end (lower end) immersed in water in the reservoir 10 and the other end (upper end) extending upward, and one end connected to the upper end of the water intake unit 12 and the other end The water discharger 13 is provided so as to extend horizontally above the water surface 6 toward the upstream. In addition, the lower end of the water intake unit 12 is immersed in the water in the reservoir 10 on the downstream side of the horizontal portion 4. The end portion 13a of the water discharge portion 13 on the opposite side to the end portion connected to the upper end of the water intake portion 12 has a closed shape. Three fountain ports 14 are provided on the lower surface 13 b of the water discharge unit 13 at equal intervals along the axial direction of the water discharge unit 13. Further, the exhaust gas treatment device 5 has a total of nine swash plates 15 provided below the respective fountain ports 14. With such a configuration, the exhaust gas treatment device 5 has a shape protruding only downward from the horizontal portion 4 when viewed from the outside.

  As shown in FIG. 2A, the swash plate 15 has a rectangular plate-shaped main body 15a and two connecting rods 15b. Each of the two connecting rods 15 b has one end connected to both side edges 15 a 1 of the main body 15 a and the other end connected to the inner peripheral surface 4 a of the horizontal portion 4. Accordingly, the swash plate 15 is fixed below the fountain port 14 inside the horizontal portion 4. Further, as shown in FIG. 2B, the swash plate 15 is fixed so that an angle θ formed by the swash plate 15 with respect to a virtual line A extending vertically downward from the fountain port 14 is 45 °. That is, the swash plate 15 is fixed so as to be inclined downward with respect to the flow direction of the exhaust gas. An oxidation catalyst 17 is provided on the surface of the main body 15a.

Next, the operation of the exhaust gas treatment apparatus according to Embodiment 1 will be described.
As shown in FIG. 1, exhaust gas generated in each combustion chamber of the diesel engine 1 is exhausted and collected in the exhaust manifold 2 and then circulates in the exhaust pipe 3. When the exhaust gas flows into the horizontal portion 4, the horizontal portion 4 has a shape that becomes narrower in the flow direction of the exhaust gas. Therefore, as the exhaust gas flows through the horizontal portion 4, the volume of the exhaust gas decreases, and accordingly The exhaust gas pressure rises. Then, a pressure difference is generated between the upstream side and the downstream side in the horizontal portion 4. Since the lower end of the water intake portion 12 is immersed in the water in the reservoir portion 10 on the downstream side of the horizontal portion 4, the water surface 6 is pushed by this pressure difference, and the water in the reservoir portion 10 is moved into the water intake portion 12. And then flows into the water discharge unit 13. The water that has flowed into the water discharge unit 13 is ejected downward from each of the three fountain ports 14. The water ejected from the fountain port 14 returns to the reservoir 10 again while wetting each of the swash plates 15. The water ejected from the fountain port 14 absorbs PM and nitrogen dioxide (NO ₂ ) in the exhaust gas by coming into contact with the exhaust gas flowing through the horizontal portion 4, so that the PM in the exhaust gas that has passed through the horizontal portion 4 And the NO ₂ concentration decreases. When water ejected from the fountain port 14 returns into the reservoir 10, the water passes through the filter member 16, so that the PM absorbed by the water is captured by the filter member 16. This facilitates PM recovery during maintenance of the exhaust gas treatment device 5.

Next, based on FIG. 3, the water ejected from the fountain outlet 14 will be described in detail the operation of absorbing PM and NO ₂ in the exhaust gas.
Since the swash plate 15 is provided so as to incline downward in the flow direction of the exhaust gas, when the exhaust gas collides with the main body 15a of the swash plate 15, the swash plate flows diagonally downward along the main body 15a. Since the surface of the main body 15a is wet with water ejected from the fountain port 14 (see FIGS. 1 and 2), the exhaust gas comes into contact with water while flowing along the main body 15a. Since the swash plate 15 is inclined downward in the flow direction of the exhaust gas, the contact time with the water increases as compared with the case where the exhaust gas flows only in the horizontal direction. Thereby, more PM and NO ₂ in the exhaust gas are absorbed by water. The reason why PM and NO ₂ are absorbed by water is that PM is fine particles and NO ₂ is relatively easily dissolved in water. On the other hand, since nitric oxide (NO) hardly dissolves in water in the same NO _x , it passes through the horizontal portion 4 (see FIGS. 1 and 2) as it is and is released into the atmosphere. However, since the oxidation catalyst 17 is provided on the surface of the main body 15a, NO in the exhaust gas is oxidized and becomes NO ₂ while the exhaust gas flows along the main body 15a. As a result, NO oxidized to NO ₂ is absorbed by water and removed from the exhaust gas, so PM and NO _x in the exhaust gas are removed by the exhaust gas treatment device 5 (see FIG. 1).

As described above, the storage portion 10 is provided so as to extend downward from the horizontal portion 4 of the exhaust pipe 3, and the shower member 11 and the swash plate 15 are accommodated in the horizontal portion 4 and the storage portion 10. Has a shape protruding only downward from the horizontal portion 4, so that the exhaust gas treatment device 5 can be made compact. Moreover, since exhaust gas flows through the water in the reservoir 10 and no back pressure is applied, it is possible to prevent the diesel engine 1 from being loaded. Further, since the PM and NO _x in the exhaust gas is removed by water alone, it is possible to suppress the use cost.

  In the first embodiment, the oxidation catalyst 17 is provided on the surface of the main body 15a of the swash plate 15. However, the present invention is not limited to this embodiment. As shown in FIG. 4, an oxidation catalyst 27 may be provided on the upstream side of the horizontal portion 4. In this case, since the oxidation catalyst 27 does not come into contact with water, such a form is preferable when a catalyst component that is deactivated by water is included.

  In the first embodiment, the bottom of the reservoir 10 is horizontal, but is not limited to this form. As shown in FIG. 4, the bottom 10 a of the reservoir 10 may have a downward slope toward the exhaust gas flow direction. With such a shape, the volume of the reservoir 10 is reduced, so that the amount of water used can be reduced, the exhaust gas treatment device 5 can be made more compact, and the usage cost can be reduced. Moreover, since the depth of the storage part 10 can be ensured in the downstream of the horizontal part 4, the lower end of the water intake part 12 can be reliably immersed in the water in the storage part 10 while reducing the amount of water used. The water can be surely pumped into the shower member 11.

  In the first embodiment, the exhaust pipe 3 may be provided with a cooling device 20 for cooling the exhaust gas. The cooling device 20 is a member that communicates with a radiator (not shown) of the diesel engine 1 and through which cooling water flows. For example, as shown in FIG. 5 (a), the inside of the exhaust pipe may be provided so as to be semicircular, or as shown in FIG. 5 (b), the inside of the exhaust pipe is formed in an annular shape. You may make it cover. The cooling device 20 can control the exhaust gas temperature released into the atmosphere.

Embodiment 2. FIG.
Next, an exhaust gas treatment apparatus according to Embodiment 2 of the present invention will be described. In the following embodiments, the same reference numerals as those in FIG. 1 are the same or similar components, and detailed description thereof will be omitted.
The exhaust gas treatment apparatus according to Embodiment 2 of the present invention is a pump for pumping water into the shower member 11 with respect to Embodiment 1 and an oxidation catalyst for oxidizing NO to NO _2. It is not used.

As shown in FIG. 6, the horizontal portion 34 extending in the horizontal direction, which is a part of the exhaust pipe 3, has the same inner diameter in the exhaust gas flow direction. In the reservoir 10, a pump 30 for pumping water in the reservoir 10 into the shower member 11 is provided at the lower end of the water intake 12. Sodium sulfite (Na ₂ SO ₃ ), which is an alkaline substance, is dissolved in the water in the reservoir 10. Further, the swash plate 15 has no oxidation catalyst on its surface. Other configurations are the same as those in the first embodiment.

When the exhaust gas generated in each combustion chamber of the diesel engine 1 starts to circulate in the exhaust pipe 3, the pump 30 is activated to supply the Na ₂ SO ₃ solution in the storage unit 10 to the water unit 12. The Na ₂ SO ₃ solution ascends in the water intake unit 12, flows into the water discharge unit 13, and is ejected from each of the three fountain ports 14 toward the swash plate 15. At this time, as in the first embodiment, the contact time between the exhaust gas and the Na ₂ SO ₃ solution is increased by the action of the swash plate 15, so that PM and NO _x in the exhaust gas are absorbed by the Na ₂ SO ₃ solution. The Here, since NO is also dissolved in the Na ₂ SO ₃ solution, not only PM and NO ₂ but also NO is absorbed in the Na ₂ SO ₃ solution without an oxidation catalyst that oxidizes NO to NO ₂ .

Thus, the exhaust gas treatment apparatus according to Embodiment 2 also has a shape that protrudes only downward from the horizontal portion 34 from the outside, and the exhaust gas circulates above the Na ₂ SO ₃ solution in the reservoir 10. by never take back pressure, since PM and NO _x in the exhaust gas is removed only by the solution of Na ₂ sO _3, it is possible to obtain the same effect as in the first embodiment. Further, by using the Na ₂ SO ₃ solution, not only NO ₂ but also NO is absorbed by the Na ₂ SO ₃ solution without using an oxidation catalyst for oxidizing NO to NO ₂ , so that exhaust gas PM and NO _x can be removed from the reactor.

In Embodiment 2, Na ₂ SO ₃ is used as the alkaline substance, but it is not limited to Na ₂ SO ₃ . Any substance such as sodium hydroxide (NaOH) or sodium carbonate (Na ₂ CO ₃ ) may be used as long as it dissolves in water and produces an alkaline solution.

In the first and second embodiments, the swash plate 15 has an angle θ formed by the swash plate 15 with respect to a virtual line A extending vertically downward from the fountain port 14 to 45 °. However, the present invention is not limited to this configuration. . Since it is sufficient that the swash plate 15 is inclined downward in the exhaust gas flow direction, any angle may be used as long as 0 ° <θ <90 °. Further, it is not necessary for all the swash plates 15 to have the same angle, and each swash plate 15 may have a different angle within the above range. Furthermore, operating conditions, and may adjust the angle of each swash plate 15 in accordance with the amount of PM and NO _x.

  In the first and second embodiments, the number of the fountain ports 14 and the swash plate 15 is limited. However, the number is not limited to the number. Can do.

1 is a schematic configuration diagram of an exhaust gas treatment apparatus according to Embodiment 1 of the present invention. 1 is a partially enlarged view of an exhaust gas treatment apparatus according to Embodiment 1. FIG. In the exhaust gas treatment apparatus according to Embodiment 1, water is a diagram for explaining an operation of absorbing PM and NO ₂ in the exhaust gas. FIG. 6 is a schematic configuration diagram of a modified example of the exhaust gas treatment apparatus according to Embodiment 1. It is an enlarged view of the cooling device provided in the modification of the exhaust gas processing apparatus which concerns on Embodiment 1. FIG. 3 is a schematic configuration diagram of an exhaust gas treatment apparatus according to Embodiment 2. FIG.

Explanation of symbols

  3 Exhaust pipes, 4, 34 Horizontal part, 5 Exhaust gas treatment device, 10 Reservoir part, 10a Bottom of (reservoir part), 11 Shower member, 12 Water intake part, 13 Water discharge part, 14 Fountain port, 15 Swash plate, 16 Filter member , 17, 27 Oxidation catalyst, 20 cooling device, 30 pump.

Claims (9)

An exhaust pipe having a horizontal portion extending in the horizontal direction and through which exhaust gas flows;
A storage portion that is provided to extend downward from the horizontal portion and stores water;
A water intake portion having one end immersed in the water and the other end extending upward, a water discharge portion provided with one end connected to the other end of the water intake portion and the other end extending above the water, and the water discharge A shower member having at least one fountain opening provided on the lower surface of the unit;
A swash plate provided below the fountain port,
The water in the reservoir is sequentially circulated through the water intake and the water discharger, and is ejected from the fountain port toward the swash plate.
The swash plate is an exhaust gas treatment device provided so as to be inclined downward toward the flow direction of the exhaust gas.   The exhaust gas treatment apparatus according to claim 1, wherein the horizontal portion has a shape that becomes narrower in a flow direction of the exhaust gas. A pump,
The exhaust gas treatment apparatus according to claim 1, wherein the pump sends water in the reservoir to the water intake unit and the water discharge unit.   The exhaust gas treatment apparatus according to any one of claims 1 to 3, wherein an alkaline substance is dissolved in the water.   The exhaust gas treatment apparatus according to any one of claims 1 to 3, wherein an oxidation catalyst is provided on the swash plate.   The exhaust gas treatment apparatus according to any one of claims 1 to 3, wherein an oxidation catalyst is provided in the exhaust pipe upstream of the horizontal portion.   The exhaust gas treatment apparatus according to any one of claims 1 to 6, wherein a filter member is provided below the swash plate.   The exhaust gas treatment apparatus according to any one of claims 1 to 7, wherein a bottom portion of the storage portion has a downward slope toward a flow direction of the exhaust gas.   The exhaust gas treatment apparatus according to claim 1, wherein the exhaust pipe is provided with a cooling device.

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