JP2002181301A - Exhaust gas boiler preventing overheat - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent overheat, when an exhaust gas boiler stops. SOLUTION: In the exhaust gas boiler, an inlet chamber 13 is provided on the upstream side of the part of installation of a heat exchanger 3 of a gas passage and the inlet chamber and the heat exchanger are partitioned from each other by a heat exchange inlet wall 9, having a heat exchanger inlet 7. A bypass opening 6 for sending introduced exhaust gas, by bypassing, to the gas passage on the downstream side of the part of installation of the heat exchanger is provided in the surface of a wall of the inlet chamber different from the heat exchange inlet wall, and a bypass damper 8 closing up the heat exchanger inlet 7 and the bypass opening 6 alternatively is provided. A double plate composed of an inside plate 11 and an outside plate 12 and surrounding the heat exchanger inlet 7 is provided upright on the wall surface on the inlet chamber 13 side of the heat exchange inlet wall 9 and at the position of contact of the bypass damper 8 on the occasion of closure thereof, and a packing 10 is fitted in the gap of the double plate. Penetration of the exhaust gas into a heat exchange part is thereby prevented, and overheating is prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an exhaust gas boiler capable of preventing overheating.

[0002]

2. Description of the Related Art There is an exhaust gas boiler that recovers heat from exhaust gas generated in a gas turbine or the like and obtains hot water or steam to effectively use the heat. An exhaust gas boiler uses surplus exhaust gas, and an exhaust gas generating side such as a gas turbine operates regardless of the convenience of the boiler. If the exhaust gas is supplied to the exhaust gas boiler while the operation of the exhaust gas boiler is stopped, the exhaust gas boiler is overheated because it only absorbs heat and does not take out heat. for that reason,
It is necessary to stop the introduction of exhaust gas into the exhaust gas boiler when the operation of the exhaust gas boiler is stopped. Is preventing.

However, as described in JP-B-63-24202, a gap remains even when the damper is closed.
The exhaust gas may enter the heat exchanger installation part, and the exhaust gas may overheat the exhaust gas boiler. Tokunosho 6
In the case of 3-24202, when the operation of the exhaust gas boiler is stopped, the air intake valve is opened and the air is introduced into the heat exchanger installation part, so that the pressure in the heat exchanger installation part is higher than the pressure in the bypass flue, Exhaust gas is prevented from entering the exchanger installation section to prevent overheating. However, in order to prevent overheating in the above configuration, it is necessary that the exhaust gas is induced by an induction ventilator. If the exhaust gas is not induced, overheating cannot be prevented. Even if the exhaust gas is completely prevented from entering, overheating may occur.

[0004]

An object of the present invention is to prevent overheating when the exhaust gas boiler is stopped.

[0005]

SUMMARY OF THE INVENTION The present invention relates to an exhaust gas boiler in which a heat exchanger is installed in the middle of a gas passage through which high-temperature exhaust gas passes, and heat of the exhaust gas is recovered by the heat exchanger. An inlet chamber is provided upstream of the heat exchanger installation section, and a partition is formed between the inlet chamber and the heat exchanger by a heat exchange inlet wall having a heat exchanger inlet opening at the center of the gas passage. On a wall separate from the exchange inlet wall, there is a bypass port that sends the introduced exhaust gas to the gas passage downstream of the heat exchanger installation section and sends it to the heat exchanger. The present invention relates to an exhaust gas boiler provided with a bypass damper to be closed. In the case of the first aspect, the inner and outer double plates comprising the inner plate and the outer plate surrounding the heat exchanger inlet at a position on the side wall surface of the heat exchange inlet wall where the bypass damper comes into contact when the bypass damper is closed. Set up a board, 2
By inserting the packing into the gap between the heavy plates, it is possible to prevent exhaust gas from entering the heat exchange section and prevent overheating.

According to a second aspect of the present invention, in the exhaust gas boiler, a heat insulating material is attached to the blade of the bypass damper. In the case of the third aspect, the blade of the bypass damper is formed of a plate-shaped heat insulating material and the heat insulating material. It has a three-layer structure composed of metal plates sandwiched from the front and back. By attaching a damper heat insulating material to the bypass damper, heating of the bypass damper is prevented, and heat in the inlet chamber is prevented from reaching the heat exchanger, thereby preventing overheating.

According to a fourth aspect, in the exhaust gas boiler, a heat insulating material is attached to a wall surface of the inlet chamber facing the gas passage. By attaching a heat insulating material to the inlet chamber, heating of the boiler wall is prevented, and heat of the inlet chamber is prevented from reaching the heat exchanger, thereby preventing overheating.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a perspective view of an exhaust gas hot water boiler embodying the present invention with an inlet chamber open, FIG. 2 is a longitudinal sectional view of a boiler embodying the present invention, FIG. 3 is a partially enlarged view of FIG. FIG. 4 is an explanatory diagram of a heat transfer situation in a conventional boiler.
The exhaust gas boiler has a substantially rectangular parallelepiped shape.
, And the periphery of the boiler wall 1 is surrounded by an outer heat insulating material 2. A gas inlet 4 is provided at an upper portion of a side surface of the exhaust gas boiler, and a gas outlet 5 is provided at an upper surface of the exhaust gas boiler, and a substantially U-shaped gas passage is provided therein. A gas passage at a portion entering from the gas inlet 4 is defined as an inlet chamber 13, and a heat exchanger 3 including a water pipe for heat absorption is provided downstream of the inlet chamber 13.

Between the inlet chamber 13 and the heat exchanger 3, there is provided a heat exchange inlet wall 9 which is a horizontal wall for blocking a gas passage, and a circular hole is made in the center of the wall. Exhaust gas entering from 4 is sent to heat exchanger 3 as heat exchanger inlet 7. A circular hole is also formed in the side wall of the inlet chamber 13, and the hole serves as a bypass port 6 for sending the exhaust gas entering from the gas inlet 4 to the gas passage downstream of the heat exchanger 3 installation portion. An intermediate portion between the bypass port 6 and the heat exchanger inlet 7 in the inlet chamber 13 is composed of a rotating shaft and a blade connected to the rotating shaft. By moving the blade, the bypass port 6 and the heat exchanger inlet 7 are respectively connected. Alternatively, a bypass damper 8 for blocking is provided.

On the side wall surface of the inlet chamber 13 of the heat exchange inlet wall 9,
A double annular plate composed of the inner plate 11 and the outer plate 12 and surrounding the heat exchanger inlet 7 is provided upright so as to be perpendicular to the heat exchange inlet wall 9, and is provided in a gap between the inner plate 11 and the outer plate 12. The packing 10 is sandwiched. The upper end of the packing 10 is higher than the upper ends of the inner plate 11 and the outer plate 12 so that the packing 10 contacts the bypass damper 8 when the bypass damper 8 is closed. The packing 10 is connected to the heat exchange inlet wall 9 in accordance with the height of the rotating shaft of the bypass damper 8.
, The gap can be prevented from occurring when the heat exchanger inlet 7 is blocked by the bypass damper 8. A damper heat insulating material 14, which is a plate-shaped heat insulating material, is attached to the blade portion of the bypass damper 8. Although the bypass damper 8 can have a heat insulating effect even if it has a two-layer structure of the damper heat insulating material 14 and the metal plate 15, the damper heat insulating material 14
It is preferable to form a three-layer structure in which the front and rear are sandwiched by a metal plate 15 because the heat insulating material can be prevented from peeling off.

An outer heat insulating material 2 is wound around the outside of the boiler wall 1 in the same manner as a normal boiler. 16 so that heat from the inlet chamber 13 is not transmitted to the boiler wall 1.

When the supply of hot water is required, the bypass damper 8 closes the bypass port 6, opens the heat exchanger inlet 7, and sends the exhaust gas introduced into the inlet chamber 13 to the heat exchanger 3. When water is supplied from one end of the heat exchanger 3, the water flows in the heat exchanger 3, absorbs heat contained in the exhaust gas, becomes hot water, and emerges from the other end. The exhaust gas passing through the heat exchanger 3 turns at the lower part of the boiler and exits through the gas outlet 5 at the upper part of the boiler. When the supply of hot water is unnecessary, the heat exchanger inlet 7 is closed by the bypass damper 8, the bypass port 6 is opened, and the exhaust gas introduced into the inlet chamber 13 passes through the heat exchanger 3 without passing through the heat exchanger 3. Also sent downstream. Since the supply of water to the heat exchanger 3 is stopped, the flow of water in the heat exchanger 3 is stopped. The exhaust gas passing through the bypass port 6 exits through the gas outlet 5 at the top of the boiler.

In the conventional boiler, even if the heat exchanger inlet 7 is closed by the bypass damper 8, the heat exchanger 3 may be heated by the exhaust gas that enters the heat exchanger 3 through the gap generated in the bypass damper portion. there were. Further, the exhaust gas flowing on the surface of the bypass damper 8 heats the bypass damper 8, and the heat generated from the bypass damper 8 to the heat exchanger 3 may overheat the heat exchanger 3.
Further, since the heat exchanger 3 and the boiler wall 1 are fixed by welding, or when the exhaust gas heats the boiler wall 1 in the inlet chamber 13, heat reaches the heat exchanger 3 via the boiler wall 1,
The heat exchanger 3 was sometimes heated.

In the case of the present invention, by installing the packing 10 between the bypass damper 8 and the heat exchange inlet wall 9, it is possible to prevent a gap from being formed when the heat exchanger inlet 7 is closed by the bypass damper 8. Exhaust gas can be prevented from entering the vessel 3. Further, since the damper heat insulating material 14 is attached to the bypass damper 8, the heat in the inlet chamber 13 heats the bypass damper 8, so that heat can be prevented from reaching the heat exchanger 3 through the bypass damper 8. . Furthermore, since the boiler wall heat insulating material 16 is provided on the boiler wall 1 of the inlet room 13, heat in the inlet room 13 is reduced.
Can be prevented from reaching the heat exchanger 3 through the boiler wall 1.

[0015]

According to the present invention, it is possible to prevent the exhaust gas boiler from being overheated when the exhaust gas boiler is stopped.

[Brief description of the drawings]

FIG. 1 is a perspective view of an exhaust gas boiler embodying the present invention with an inlet chamber portion opened.

FIG. 2 is a longitudinal sectional view of a boiler embodying the present invention.

FIG. 3 is a partially enlarged view of FIG. 2;

FIG. 4 is an explanatory diagram of a heat transfer situation in a conventional boiler.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Boiler wall 2 Outer heat insulator 3 Heat exchanger 4 Gas inlet 5 Gas outlet 6 Bypass port 7 Heat exchanger inlet 8 Bypass damper 9 Heat exchange inlet wall 10 Packing 11 Inner plate 12 Outer plate 13 Inlet room 14 Damper heat insulator 15 Metal Plate 16 Boiler wall insulation

Claims (4)

[Claims] 1. An exhaust gas boiler in which a heat exchanger is installed in the middle of a gas passage through which high-temperature exhaust gas passes, and heat of the exhaust gas is recovered by the heat exchanger. An inlet chamber is provided on the upstream side, and a partition between the inlet chamber and the heat exchanger is created by a heat exchange inlet wall that has a heat exchanger inlet with the center of the gas passage open. Has a bypass port for bypassing the introduced exhaust gas to a gas passage downstream of the heat exchanger installation section, and a bypass damper for selectively closing the heat exchanger inlet and the bypass port. In the exhaust gas boiler, an inner / outer double plate composed of an inner plate and an outer plate surrounding the heat exchanger inlet is set up on the inlet chamber side wall surface of the heat exchange inlet wall, where the bypass damper is in contact when the bypass damper is closed. Set up, 2
Exhaust gas boiler to prevent overheating, characterized by packing fitted in the gap between heavy plates. 2. An exhaust gas boiler in which a heat exchanger is installed in the middle of a gas passage through which high-temperature exhaust gas passes and heat of the exhaust gas is recovered by the heat exchanger. An inlet chamber is provided on the upstream side, and a partition between the inlet chamber and the heat exchanger is created by a heat exchange inlet wall that has a heat exchanger inlet with the center of the gas passage open. Has a bypass port for bypassing the introduced exhaust gas to a gas passage downstream of the heat exchanger installation section, and a bypass damper for selectively closing the heat exchanger inlet and the bypass port. An exhaust gas boiler for preventing overheating, wherein a heat insulating material is attached to a blade portion of a bypass damper. 3. The exhaust gas boiler according to claim 2, wherein the blade portion of the bypass damper has a three-layer structure including a plate-shaped heat insulating material and a metal plate sandwiching the heat insulating material from front and rear. Exhaust gas boiler that prevents overheating. 4. An exhaust gas boiler in which a heat exchanger is installed in the middle of a gas passage through which high-temperature exhaust gas passes, and heat of the exhaust gas is recovered by the heat exchanger. An inlet chamber is provided on the upstream side, and a partition between the inlet chamber and the heat exchanger is created by a heat exchange inlet wall that has a heat exchanger inlet with the center of the gas passage open. Has a bypass port for bypassing the introduced exhaust gas to a gas passage downstream of the heat exchanger installation section, and a bypass damper for selectively closing the heat exchanger inlet and the bypass port. An exhaust gas boiler for preventing overheating, wherein a heat insulating material is attached to a wall surface facing a gas passage of an inlet chamber.