JP7259704B2 - Dust remover for heat transfer tubes - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat transfer tube dust removing device for removing dust such as ash adhering to heat transfer tubes.

In general, a boiler for recovering waste heat is provided after an incinerator for burning and incinerating waste such as household waste. A boiler is provided with heat transfer tubes such as a superheater, an evaporator, and an economizer. Boilers are classified into a tail-end boiler (see FIG. 4, Patent Document 1) and a vertical boiler (see FIG. 5, Patent Document 2) according to the arrangement of heat transfer tubes and the flow of exhaust gas.

As shown in FIG. 4, in the tail-end boiler, the straight tube portion 61a of the heat transfer tube 61 is arranged substantially perpendicular to the ground. Then, the flow of the exhaust gas in the casing 62 is made substantially parallel to the ground, the inflow end 61b and the outflow end 61c of the heat transfer tube 61 are fixed to the ceiling portion 62-1 of the casing 62, and the headers 63 and 64 are attached. Connecting.

As shown in FIG. 5, in a vertical boiler, a straight tube portion 71a of a heat transfer tube 71 is arranged substantially parallel to the ground. Then, the flow of the exhaust gas in the casing 72 is made substantially perpendicular to the ground, and the inlet end 71b and the outlet end 71c of the heat transfer tube 71 are passed through the wall 72-2 of the casing 72 and connected to the headers 73 and 74. do.

By the way, regardless of the type of boiler, when dust such as ash adheres to the heat transfer tubes, the heat recovery efficiency of the heat transfer tubes decreases. Therefore, it is necessary to remove the dust in order to maintain the heat recovery efficiency of the heat transfer tubes.

For example, in a tail-end boiler, a hammering device is generally used to remove dust adhering to the heat transfer tubes. That is, as shown in FIG. 4, heat transfer tube groups 61 (heat transfer tube groups arranged in a direction perpendicular to the plane of FIG. 4) are connected by horizontal connecting members 65a and 65b extending in a direction perpendicular to the plane of FIG. Then, by hitting the horizontal connecting members 65a and 65b with a hammering device, the heat transfer tube group 61 is vibrated, and dust adhering to the heat transfer tube group 61 is removed.

On the other hand, in a vertical boiler, a soot blower that injects steam toward the heat transfer tubes is generally used to remove dust adhering to the heat transfer tubes. However, Patent Document 2 discloses a heat transfer tube dust removing device that uses a hammering device instead of a soot blower. That is, as shown in FIG. 5, heat transfer tube groups 71 (heat transfer tube groups 71 arranged in a direction perpendicular to the plane of FIG. 5) are supported by horizontal support members (not shown) extending in a direction perpendicular to the plane of FIG. Then, one end of the supporting member is fixed to the first wall 72-1 of the casing 72, and the other end of the supporting member is fixed to the second wall facing the first wall 72-1 of the casing 72 (back side of the page of FIG. 5). side wall), and the hammering device 75 is fixed to the first wall 72-1. Then, by hitting the first wall 72-1 with the hammering device 75, the support member and the heat transfer tube group 71 are vibrated, and dust adhering to the heat transfer tube group 71 is removed.

JP-A-59-142399 JP 2006-292265 A

However, in the conventional vertical boiler heat transfer tube dust removal device (the heat transfer tube dust removal device described in Patent Document 2), the heat transfer tube 71 swings unevenly, and the feed end 71b and the feed end 71b are uneven. Although the free end far from the wall 72-2 through which the end 71c penetrates easily swings, the fixed end near the wall 72-2 does not swing easily. Dust tends to adhere to the central portion between the free end and the fixed end of the heat transfer tube 71. Since the central portion of the heat transfer tube 71 cannot be shaken as much as the free end, dust was difficult to remove.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a heat transfer tube dust removing apparatus capable of effectively removing dust adhering to heat transfer tubes.

In order to solve the above problems, one aspect of the present invention provides a casing having a straight pipe portion substantially parallel to the ground and a bend portion, and in which exhaust gas flows in a direction substantially perpendicular to the ground. A first heat transfer tube group having an inflow end and a outflow end penetrating a first wall, a straight pipe portion substantially parallel to the ground, and a bend portion, and is attached to the first wall of the casing. a second heat transfer tube group having an infeed end and a delivery end penetrating the opposing second walls; and a vibration imparting means for vibrating the first heat transfer tube group and the second heat transfer tube group . A heat transfer tube dust removing device in which one wall and the second wall are non-rotatably fixed to the casing .

ADVANTAGE OF THE INVENTION According to this invention, the dust adhering to a heat exchanger tube can be removed effectively.

It is a longitudinal cross-sectional view of an incinerator and a boiler. 1 is a horizontal sectional view of a dust removing device according to one embodiment of the present invention; FIG. 1 is a vertical sectional view of a dust removing device of this embodiment; FIG. 1 is a horizontal sectional view of a conventional tail-end boiler; FIG. It is a side view of a conventional vertical boiler.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, a heat transfer tube dust removing device according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings. However, the heat transfer tube dust removal apparatus of the present invention may be embodied in various forms and is not limited to the embodiments set forth herein. Embodiments of the invention are provided with the intention that the disclosure of the specification will be sufficient to enable those skilled in the art to understand the invention.

FIG. 1 is a longitudinal sectional view of an incinerator 1 and a boiler 2 of the present invention. Incinerator 1 is, for example, a waste incinerator. A boiler 2 is connected to the rear stage of the incinerator 1 . The boiler 2 is provided with two direction changers 21 and 22 that bend the flow of the exhaust gas. A first radiant chamber 11, a second radiant chamber 12, and a convective heat transfer chamber 13 are formed in the boiler 2 by the deflecting portions 21 and 22 from the upstream side of the exhaust gas. The exhaust gas discharged after burning the waste in the incinerator 1 is directed upward through the first radiant chamber 11, downward through the second radiant chamber 12, and upward through the convection heat transfer chamber 13. to (substantially perpendicular to the ground).

The casings of the first radiant chamber 11 and the second radiant chamber 12 consist of water-cooled walls. The water-cooled wall receives radiant heat from the exhaust gas and generates steam. The convective heat transfer chamber 13 is provided with a screen tube 32, superheaters 34, 36, 38, and an economizer 42 from the upstream side of the exhaust gas. The superheaters 34, 36, 38 are a secondary superheater 34, a tertiary superheater 36, and a primary superheater 38 from the upstream side of the exhaust gas. The steam generated by the water-cooled walls of the first radiant chamber 11 and the second radiant chamber 12 is supplied to the primary superheater 38, secondary superheater 34 and tertiary superheater 36 in this order. The economizer 42 heats the water by heat exchange with the exhaust gas. The heated water heated by the economizer 42 is supplied to the water-cooled walls of the first radiant chamber 11 and the second radiant chamber 12 .

A separate economizer 3 is connected downstream of the boiler 2 . Exhaust gas flows downward (substantially perpendicular to the ground) through the separate economizer 3 . The separate economizer 3 is provided with an economizer 51 . The heated water heated by the economizer 51 is supplied to the economizer 42 .

2 and 3 show the heat transfer tubes of the superheaters 34, 36, 38 arranged in the convection heat transfer chamber 13 shown in FIG. 2 shows a horizontal sectional view of the casing 4 of the convection heat transfer chamber 13, and FIG. 3 shows a vertical sectional view of the casing 4. As shown in FIG. As shown in FIG. 2, the casing 4 is formed in a substantially square shape when viewed in cross section. The first wall 4-1 and the second wall 4-2 of the casing 4 face each other, and the third wall 4-3 and the fourth wall 4-4 of the casing 4 face each other.

As shown in FIG. 3, the exhaust gas flows through the casing 4 from bottom to top (substantially perpendicular to the ground). A first heat transfer tube group 5 and a second heat transfer tube group 6 are provided on the left and right sides of the casing 4 . The first heat transfer tube group 5 has a straight tube portion 5a, bend portions 5b and 5c, an inlet end portion 5d, and an outlet end portion 5e. The straight pipe portion 5a is substantially parallel to the ground. The infeed end 5d and the outfeed end 5e pass through the first wall 4-1 of the casing 4 and are connected to the headers 7,8. As shown in FIG. 2, the first heat transfer tube group 5 is composed of a plurality of first heat transfer tubes 5-1 arranged in parallel in the horizontal direction.

As shown in FIG. 3 , the second heat transfer tube group 6 is bilaterally symmetrical with the first heat transfer tube group 5 . The second heat transfer tube group 6 has a straight tube portion 6a, bend portions 6b and 6c, an inlet end portion 6d, and an outlet end portion 6e. The straight pipe portion 6a is substantially parallel to the ground. The infeed end 6d and the outfeed end 6e pass through the second wall 4-2 of the casing 4 and are connected to the headers 9,10. As shown in FIG. 2, the second heat transfer tube group 6 is composed of a plurality of second heat transfer tubes 6-1 arranged in parallel in the horizontal direction.

As shown in FIG. 2, the plurality of first heat transfer tubes 5-1 are connected by first horizontal connecting members 23a and 23b extending in the horizontal direction. As shown in FIG. 3 , the first horizontal connecting members 23 a and 23 b are arranged at the top and bottom of the first heat transfer tube group 5 . The first horizontal connecting members 23a and 23b are arranged at the free ends of the first heat transfer tube group 5 (near the bend portion 5b). The bend portion 5c protrudes outside the first wall 4-1 of the casing 4. As shown in FIG.

As shown in FIG. 2, like the first heat transfer tube group 5, the second heat transfer tube group 6 is connected by horizontally extending second horizontal connecting members 24a and 24b. As shown in FIG. 3 , the second horizontal connecting members 24 a and 24 b are arranged at the top and bottom of the second heat transfer tube group 6 . The second horizontal connecting members 24a and 24b are arranged at the free ends of the second heat transfer tube group 6 (near the bend portion 6b). The bend portion 6c protrudes outside the second wall 4-2 of the casing 4. As shown in FIG.

As shown in FIG. 3, the bend portions 5b of the first heat transfer tube groups 5 or their vicinity are connected by a first vertical connecting member 25 extending in the vertical direction. In other words, the bend portions 5b are bundled by the first vertical connecting member 25. As shown in FIG.

As with the first heat transfer tube group 5, the bend portions 6b of the second heat transfer tube groups 6 or their vicinity are connected by a second vertical connecting member 26 extending in the vertical direction. In other words, the bend portions 6b are bundled by the second vertical connecting member 26. As shown in FIG.

As shown in FIG. 2, one ends of the first horizontal connecting members 23a and 23b protrude outside the third wall 4-3 of the casing 4. As shown in FIG. Upper and lower first hammering devices 27a and 27b are attached to one ends of the first horizontal connecting members 23a and 23b. The first hammering devices 27a, 27b strike the first horizontal connecting members 23a, 23b. The first hammering devices 27a and 27b are, for example, air knockers. The air knocker has a piston inside, and is configured such that the piston hits the base plate by air pressure. In addition to the air knocker, a hammer-type hammering device that strikes with a hammer may be used. The first hammering devices 27a and 27b and the first horizontal connecting members 23a and 23b constitute first vibration imparting means for vibrating the first heat transfer tube group 5. As shown in FIG.

Similar to the first horizontal connecting members 23a, 23b, one end of the second horizontal connecting members 24a, 24b protrudes outside the third wall 4-3 of the casing 4. As shown in FIG. Upper and lower second hammering devices 28a and 28b are attached to one ends of the second horizontal connecting members 24a and 24b. The second hammering devices 28a, 28b strike the second horizontal connecting members 24a, 24b. The second hammering devices 28a, 28b are, for example, air knockers. The second hammering devices 28a, 28b and the second horizontal connecting members 24a, 24b constitute second vibration imparting means for vibrating the second heat transfer tube group 6. As shown in FIG.

The configuration of the dust removing device of this embodiment has been described above. According to the dust removing device of this embodiment, the following effects are obtained.

When the first hammering devices 27a and 27b hit the first horizontal connecting members 23a and 23b, the first heat transfer tube group 5 vibrates. The magnitude of the shaking is greatest at the free end of the first heat transfer tube group 5 . Since dust tends to adhere to the free end of the first heat transfer tube group 5 in the central portion of the casing 4, the dust adhering to the first heat transfer tube group 5 can be effectively removed. The same applies to the second heat transfer tube group 6 .

Since the vibration applying means is divided into the first vibration applying means and the second vibration applying means, each of the first heat transfer tube group 5 and the second heat transfer tube group 6 can be vibrated effectively.

Since the bend portions 5b of the first heat transfer tube groups 5 or their vicinity are connected by the first vertical connection member 25, the number of the first hammering devices 27a and 27b can be reduced. The second vertical connecting member 26 is also the same.

Since the bend portion 5c of the first heat transfer tube group 5 protrudes outside the first wall 4-1 of the casing 4, the first heat transfer tube group 5 can be supported by the first wall 4-1. The same applies to the second heat transfer tube group 6 .

Note that the present invention is not limited to being embodied in the above-described embodiments, and can be modified to other embodiments without changing the gist of the present invention.

In the above embodiment, the first heat transfer tube group is vibrated by the first vibration imparting means, and the second heat transfer tube group is vibrated by the second vibration imparting means. It may be vibrated by one vibration imparting means.

In the above embodiment, two first horizontal connecting members and first hammering devices are provided above and below the first heat transfer tube group, but one first horizontal connecting member and first hammering device may be provided. . The same applies to the second horizontal connecting member and the second hammering device.

In the above embodiment, an example in which the heat transfer tube is a superheater has been described, but the heat transfer tube may be an economizer or an evaporator. The walls of the casing may be water cooled walls.

4 Casing 4-1 First wall 4-2 Second wall 5 First heat transfer tube group 5-1 First heat transfer tube 5a Straight tube portion 5b Bend portion 5c Bend portion 5d Inlet end Portion 5e Sending end 6 Second heat transfer tube group 6-1 Second heat transfer tube 6a Straight tube portion 6b Bend 6c Bend 6d Sending end 6e Sending ends 23a, 23b 1 horizontal connecting members 24a, 24b... second horizontal connecting member 25... first vertical connecting member 26... second vertical connecting members 27a, 27b... first hammering devices 28a, 28b... second hammering devices

Claims (5)

The inlet and outlet ends extend through a first wall of the casing having a straight pipe portion substantially parallel to the ground and a bend portion such that exhaust gas flow is substantially perpendicular to the ground. a first heat transfer tube group;
A second heat transfer tube group having a straight pipe portion substantially parallel to the ground and a bend portion, and having an inflow end and a outflow end penetrating a second wall opposite the first wall of the casing. and,
Vibration applying means for vibrating the first heat transfer tube group and the second heat transfer tube group ,
A dust removing device for heat transfer tubes , wherein the first wall and the second wall are non-rotatably fixed to the casing . The vibration imparting means is
a first vibration imparting means provided on the first heat transfer tube group side for imparting vibration to the first heat transfer tube group;
2. The heat transfer tube dust removing device according to claim 1, further comprising a second vibration imparting means provided on the second heat transfer tube group side and imparting vibration to the second heat transfer tube group. The first vibration imparting means is
a first horizontal connecting member that extends horizontally and connects the first heat transfer tube group;
a first hammering device that strikes the first horizontal connecting member;
The second vibration imparting means is
a second horizontal connecting member that extends horizontally and connects the second heat transfer tube group;
3. The heat transfer tube dust removing device according to claim 2, further comprising a second hammering device for striking the second horizontal connecting member. The first vibration imparting means is
a first vertical connecting member that extends in the vertical direction and connects the straight pipe portions and/or bent portions of the first heat transfer tube groups;
The second vibration imparting means is
4. The heat transfer tube dust removing apparatus according to claim 3, further comprising: a second vertical connecting member extending in a vertical direction and connecting the straight pipe portions and/or the bent portions of the second heat transfer tube groups. one of the bend portions on the left and right sides of the first heat transfer tube group protrudes outside the first wall of the casing,
5. The heat transfer tube according to any one of claims 1 to 4, wherein one of the left and right bend portions of the second heat transfer tube group protrudes outside the second wall of the casing. Dust remover.

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