JPH09177546A - Denitrification reactor for vessel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To protect a catalyst from various external forces applied thereto by providing a plurality of catalysts whose inner part is partitioned into a number of independent passages and whose outer shape is formed to be rectangular, bringing a catalyst fixing part into contact with its one end surface and bringing a movable type catalyst fixing part into the other end surface of the catalyst. SOLUTION: A dentirification reactor causes exhaust gas introduced from an exhaust gas inlet 1a to pass through the catalysts 2b and 2a of the upstream and downstream sides arranged in horizontal directions, be discharged from an exhaust gas outlet 1b and returns and eliminate NOx contained in exhaust gas. For each of the catalysts 2a and 2b, its inner part is partitioned into a number of independent passages by a thin partition wall and its outer shape is formed to be rectangular. In order to insert this into a reactor 1, one formed to be a block shape in multi stages and multi-row is used, a catalyst fixing structure is composed of a fixing grid 7 as a catalyst fixing part, a movable grid 8 as a movable type catalyst fixing part and a grid pressing device and the catalysts 2a and 2b are held between both sides.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a denitration reactor for ships, which is installed in a ship equipped with a diesel engine and reduces and removes NO _x in exhaust gas.

[0002]

2. Description of the Related Art Today, regulation of NO _x emitted from diesel engines is being promoted for the purpose of preventing environmental pollution, and this regulation is being applied not only to land vehicles but also to ships. As a NO _x removal device in a ship, a denitration device using a catalyst is considered. A catalyst body packed in this type of denitration reactor has, for example, 15 sides.
A prismatic ceramic catalyst body having a length of 0 mm and a length of 500 mm is used, and the end surface of the ceramic catalyst body is divided into a lattice shape (for example, 30 × 30 cells) or a honeycomb shape by a thin partition wall. It is common that the minute openings are formed.

Such catalyst bodies are usually arranged in a denitration reactor, and a plurality of such catalyst bodies are arranged in the vertical and horizontal directions along the exhaust gas flow of the denitration reactor to form an aggregate. Further, Japanese Patent Application Laid-Open No. 7-139341 discloses a horizontal reactor in which the catalyst bodies are arranged so that the longitudinal positions of the catalyst bodies are sequentially displaced in the same direction, and the reactor is made compact.

[0004]

Since the above-mentioned ceramic catalyst body is brittle and easily chipped, it is necessary to consider the fixing method when filling it in the reactor.
That is, while the ship is traveling, the load applied to the catalyst body by rolling, the load applied to the catalyst body by pitching, and the catalyst body against various external forces such as shocking vibration applied to the catalyst body by waves. A structure that can do is needed.

However, the conventional denitration reactor has been improved in that the reactor can be made compact, but when it is used for a ship, it protects the catalytic body from the external force during navigation and allows it to function stably. The structure of the denitration reactor for ships that can do this has not been established.

The present invention has been made in consideration of the problems for ships in the above-mentioned conventional denitration reactor, and protects the catalytic body from various external forces applied to the catalytic body during navigation, The present invention provides a denitration reactor for a ship, which enables stable operation of the above.

[0007]

DISCLOSURE OF THE INVENTION The present invention provides a ship denitration reactor installed in an exhaust gas passage, the interior of which is partitioned into a large number of independent passages, and the outer shape of which is formed into a rectangular shape. The catalyst body, a catalyst body fixing portion that is fixed in the denitration reactor and is in contact with one end face in the longitudinal direction of a large number of catalyst bodies, and the lattice member is the other end face in the longitudinal direction of the catalyst body. A denitration reactor for a ship, comprising: a movable catalyst body fixing portion that abuts so as to be able to move forward and backward.

In the present invention, it is preferable to dispose two or more denitration reactors laterally along the exhaust gas passage. Further, it is preferable to coat the outer peripheral surface of the catalyst body with a buffer member.

As the arrangement of a large number of catalyst bodies in the present invention, those arranged in a plane orthogonal to the flow of exhaust gas are shown, and one frame of each lattice member corresponds to the end face shape of each catalyst body. Preferably. In addition, it is preferable that a crossing portion of the lattice of the grid-like member is provided with a locking piece that can come into contact with a corner of an end face of each catalyst body, and a buffering member is provided on the catalytic body contacting side of the locking piece. It is preferable.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail based on embodiments shown in the drawings. FIG. 1 is a plan view showing a configuration of a denitration reactor for a ship (hereinafter abbreviated as a reactor) according to an embodiment of the present invention, and FIG. 2 is a front view having a partial cutout. In both figures, the reactor 1 is arranged in a lateral position and is provided with a cylindrical duct that constitutes an exhaust gas flow path. Exhaust gas introduced from an exhaust gas inlet 1a passes through an upstream side catalyst body 2a and then on a downstream side. It passes through the catalyst body 2b and is led out from the exhaust gas outlet 1b.

The catalyst bodies 2a and 2b in the cylindrical duct have the same structure, are arranged coaxially along the flow of the exhaust gas, and are arranged in a large number in a plane orthogonal to the flow of the exhaust gas. As the catalyst bodies 2a and 2b, the ceramic catalyst body shown in FIG. 3 can be used, and the inside thereof is partitioned into a large number of independent passages by thin partition walls.
The outer shape is a rectangular shape. When filling the inside of the reactor 1, a block is used in which 6 rows are closely arranged in the horizontal direction and 7 columns are stacked in the vertical direction. To fill the catalyst body 2a in the reactor 1, the side cover plate 1c and the upper cover plate 1d are removed, and the catalyst bodies are stacked in order from the bottom.

In addition, between the block-shaped catalyst bodies,
As a cushioning material, 3.0 mm thick kaool paper (made by Isolite Industrial Co., Ltd.) is sandwiched. Since this cushioning material has excellent heat insulating performance at high temperatures and is highly flexible, it is also suitable for the work of closely stacking the catalyst bodies 2a. A 25 mm thick kaool wool blanket (manufactured by Isolite Industrial Co., Ltd.), which functions as a cushioning material and can prevent gas leakage, is wrapped around the outer peripheral surface of the block-shaped catalyst body. This blanket-shaped cushioning material is suitable as a high-temperature sealing material and can maintain elasticity in a high temperature range.
The physical properties of the catalyst bodies 2a and 2b are as shown in the table below.

[0013]

[Table 1]

In FIG. 4, three nozzles 3a of the suit blow 3 for preventing blockage due to particulates are arranged in parallel on the upstream side of each catalyst body 2a, 2b. In addition, in the reactor 1, when trouble occurs in the catalyst bodies 2a, 2b, the bypass pipes 4 that can bypass the catalyst bodies 2a, 2b and directly pass the exhaust gas from the exhaust gas inlet 1a to the exhaust gas outlet 1b. Is attached. Further, a partition wall 5 (see FIG. 2) having a through hole is provided between the exhaust gas inlet 1a and the upstream catalyst body 2a.
The outer wall of the reactor 1 is covered with a heat insulating material (not shown) for heat insulation.

Next, the fixing structure of the catalyst body will be described. As shown in FIG. 5, the fixing structure of the upstream catalyst body 2a and the downstream catalyst body 2b are both fixed grid 7 as a catalyst body fixing portion, movable grid 8 as a movable catalyst body fixing portion, and It is mainly composed of a grid retainer (described later), and sandwiches the catalyst body 2a or 2b from both sides thereof. With reference to FIGS. 5 to 7, the downstream catalyst fixing structure will be described as a representative example. As shown in FIG.
It is fixed by welding, and one lattice 8a corresponds to the end face shape of each catalyst body 2b.

As shown in FIG. 7, a square thin plate piece 9 serving as a locking piece is attached to the side of the catalyst 2b at the intersection of the movable grid 8, and the thin plate piece 9 has a surface on the surface thereof. Further, the cushioning material 10 is fixed with an adhesive. As the buffer material 10, an interram mat (manufactured by Sumitomo 3M Co., Ltd.) which is used as a gas sealing material for an automobile exhaust gas purifying catalyst case and has excellent dimensional stability in a heat expansion cycle can be used.

The thin plate piece 9 can come into contact with the corner of each catalyst body 2b, whereby the catalyst body 2b can be fixed with almost no obstruction to the flow of exhaust gas. Since the corners of the catalyst body 2b have particularly high strength, there is no risk of damage to the catalyst body 2b. In addition to the thin plate pieces 9 at the intersections 8b (four positions on the movable grid 8), a contact plate 11 having a slightly larger area than the thin plate pieces 9 is fixed as shown in FIG. 7B. . The contact plates 11 are each pressed by a grid pressing device. Further, fixed metal fittings 8d each having a slit 8c are attached in parallel at a total of four places to the upper outer frame and the lower outer frame of the movable grid 8. As shown in FIG.
It is fixed to the inner wall of the top plate and the inner wall of the bottom plate of the reactor 1 via the nut 13 and the nut 13. Therefore, if the bolt 12 is loosened, the movable grid 8 can be moved by the depth of the slit 8c.

As shown in the plan view of FIG. 9, the grid pressing device includes a plate-like support fitting 14 horizontally projected from the side wall 1e of the reactor 1 and a bolt 15 screwed to the support fitting 14. It is configured, more specifically, the support fitting 1
Nuts 1 fixed coaxially on both sides of the through hole drilled in 4
By rotating the bolt 15 clockwise or counterclockwise with respect to 4a, the movable grid 8 can be moved in the arrow A direction or the arrow B direction.

On the other hand, the fixed grid 7 has a structure in which the backing plate 11 and the fixing metal fitting 8d are removed from the movable grid 8 and is fixed to the inner wall of the top plate and the inner wall of the bottom plate of the reactor 1 by welding.

A pedestal 22 is attached to the leg portion 20 (see FIG. 2) of the reactor 1 via a shock absorbing material 21 such as butyl rubber, so that vibrations and the like generated from the diesel engine can be absorbed. It is like this.

According to this embodiment having such a structure, one end surface of the catalyst bodies 2a, 2b is supported by the fixed grid 7 via the cushioning material 10, and the other end surface is
The catalyst body 2 is supported by the movable grid 8 which can move forward and backward with respect to the catalyst bodies 2a and 2b via the cushioning material 10.
It is possible to fix a and 2b with an optimum pressing force, and as a result, it is possible to reliably protect the catalyst bodies 2a and 2b even against gravitational acceleration during pitching, which is also 2G.
Further, the side wall of the reactor 1 has sufficient proof strength against the external force applied by the rolling, and the catalyst bodies 2a, 2
Since the outer peripheral surface of b is covered with the cushioning member, an external force is not directly applied to the catalyst bodies 2a and 2b.
Since the packing is also sandwiched between the two bodies, the catalyst bodies 2a and 2b can be reliably protected.

The denitration reactor of the present invention basically comprises a catalyst body filled in the exhaust gas passage, one end surface of which is fixed by a fixed grid, and the other end surface of which is fixed by a movable grid. However, regarding the constitution of the above catalyst body, NO _{x at} the outlet of the reactor at 100% load
The number of arrays and the number of processing stages are determined so as to satisfy the regulation value. In this embodiment, the upstream catalyst body 2a is arranged for the primary reaction, and the downstream catalyst body 2a for the secondary reaction.
Is arranged.

Further, in the movable catalyst fixing portion of the present invention, the grid pressing device is composed of bolts in the above-mentioned embodiment, but the invention is not limited to the use of screws, and it is possible to extend and contract without locking the flow of exhaust gas. As the mechanism, any mechanical element such as a mechanism for feeding a rack by using a gear such as a pinion rack mechanism, a mechanism for stretching and fixing an insertion tube in a double tube, and the like can be used.

[0024]

As is apparent from the above description,
According to the denitration reactor for ships of the present invention, the catalyst body can be protected from various external forces applied to the catalyst body during navigation, so that the catalyst body can function stably even in a harsh environment at sea navigation. In addition, it has an advantage that the catalyst body can have a long life.

[Brief description of the drawings]

FIG. 1 is a plan view of a reactor according to an embodiment of the present invention.

FIG. 2 is a front view having a partial cutout of FIG.

FIG. 3 is a perspective view showing a shape of a catalyst body according to an example.

FIG. 4 is a left side view of FIG. 1;

FIG. 5 is a front view showing a catalyst body fixing structure according to an example.

FIG. 6 is an explanatory diagram showing a configuration of a movable grid according to an example.

FIG. 7 is an enlarged view of a main part of a movable grid.

FIG. 8 is an enlarged view of a main part showing a fixing member of a movable grid.

FIG. 9 is an enlarged plan view showing the configuration of a grid pressing device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Reactor 1a Exhaust gas inlet 1b Exhaust gas outlet 2 Catalyst body 3 Suit blow 4 Bypass pipe 5 Partition wall 7 Fixed grid 8 Movable grid 9 Thin plate piece 10 Buffer material 11 Patch plate 12 Bolt 13 Nut 14 Support metal fitting 15 Bolt

Claims (6)

[Claims] 1. A denitration reactor for a ship installed in an exhaust gas flow passage, wherein a plurality of catalyst bodies each having an interior partitioned into a number of independent passages and having a rectangular outer shape, and the denitration reactor. A catalyst member fixing portion that is fixed inside the catalyst member and is in contact with one end face in the longitudinal direction of the plurality of catalyst members; and a lattice member that can move forward and backward with respect to the other end face in the longitudinal direction of the catalyst member. A denitrification reactor for a ship, comprising: a movable catalyst body fixing portion that abuts against the vessel. 2. The denitration reactor for ships according to claim 1, wherein two or more denitration reactors are arranged laterally along the exhaust gas passage. 3. The denitration reactor for ships according to claim 1, wherein the outer peripheral surface of the catalyst body is covered with a buffer member. 4. The plurality of catalyst bodies are arranged in a plane orthogonal to the flow of exhaust gas, and one frame of each of the lattice members corresponds to an end face shape of each of the catalyst bodies. The denitration reactor for ships according to any one of claims 1 to 3. 5. The denitration reactor for a ship according to claim 4, wherein a locking piece capable of contacting a corner of the end face of each catalyst body is provided at the intersection of the grids of the grid-shaped member. 6. The denitration reactor for a ship according to claim 5, wherein a buffer member is provided on a side of the locking piece that abuts the catalyst body.