JP3222032U - Economizer - Google Patents

Abstract

To provide an economizer having a structure that can efficiently heat water and that is easy to inspect and clean. SOLUTION: In an economizer which heats water by flue gas generated in a boiler, the flue gas is circulated to a cylindrical water pipe 11 which has an inlet and an outlet formed on the side and through which the water passes. A plurality of gas pipes erected for the purpose are disposed in the fan-shaped portion of the water pipe, and the combustion gas introduced from the bottom surface side of the water pipe is folded back at the top of the water pipe and flows downward. The water in the water pipe is efficiently heated by being folded back at the lower portion of the water pipe and flowing upward and flowing out from the upper surface side of the water pipe. [Selected figure] Figure 5

Description

  The present invention relates to an economizer that preheats water supplied to a boiler with flue gas from the boiler.

BACKGROUND ART Economizers that preheat water supplied to a boiler with heat of flue gas discarded from the boiler are widely and generally used because heat can be effectively used.
For example, the economizer (FIG. 10) described in Patent Document 1 arranges a large number of water pipes in the flue 2 through which the flue gas generated in the boiler flows, and the water flowing in each water pipe exchanges heat. It is configured to be heated by Further, by providing the end plate 5 outside the flue with the U-shaped pipe 4 outside the flue, the path of the water pipe is turned back, and the passage is lengthened by repeating penetrating the flue 2 in the opposite direction again The water pipe in the flue 2 is provided with a large number of fin pipes 3 in order to improve heat absorption.

  According to the economizer described in Patent Document 1, in the flue 2 connected to the boiler 1, the water supply path is folded back at the upper and lower portions of the flue to arrange a large number of vertical water pipes in the flue, A turnaround (U-tube 4) is provided inside the flue. And, by arranging the spray nozzle 7 for spraying the blow water from the boiler 1 through the blow pipe 6 toward the water pipe in the flue, the blow water is sprayed toward the water pipe so that the folded portion is immersed in the water Blow water is stored in a water tank (water part 9) at the lower part of the flue, and water overflowed from the water tank is drained from the drainage pipe 8.

Patent No. 3587895

According to the conventional economizer structure, since the water in the water pipe is heated by the water supply path (water pipe) disposed in the flue 2, the heat absorption efficiency to water flowing in the water pipe is poor, There was a problem that heating could not be performed as expected. In addition, since the volume of the water pipe is small, there is a limit to the amount of retained water (for example, 10 to 20 liters) of the heated water, and structural problems such that sufficient heating can not be maintained if the amount of water supplied per hour increases. was there.
In addition, since the combustion exhaust gas comes in contact with the fin tube 3 which is a protrusion provided on the outer side of the water tube, there is a problem that dirt is easily attached and it is difficult to remove the dirt.

Therefore, the present inventor has proposed an economizer (Japanese Patent Application No. 2019-054551) shown in FIGS. 7 to 9 as a structure capable of heating water efficiently.
This economizer has a combustion exhaust gas introduction chamber 20 facing the combustion exhaust gas introduction port 15 at the lower end position in the cylindrical water pipe 11 forming the inlet 12 and the outlet 13 on the side and passing water, and the combustion exhaust gas introduction chamber A lower connecting chamber 30 partitioned with respect to 20 is provided, and a combustion exhaust gas discharge chamber 40 facing the combustion exhaust gas outlet 19 at an upper end position in the water pipe and a combustion exhaust gas discharge chamber 40 are divided to a combustion exhaust gas discharge chamber 40 An upper annular connecting chamber 50 is provided surrounding the

  The lower partition wall 14 and the upper partition wall 17 extend along the inner wall periphery of the water pipe 11 so as to connect the combustion exhaust gas introduction chamber 20 and the upper annular connection chamber 50 in order to circulate the combustion exhaust gas in the water pipe 11 Lower partition wall 14 and upper partition wall 17 at an inner position of the first gas pipe so as to connect the plurality of first gas pipes 61 erected and connecting the upper annular connection chamber 50 and the lower connection chamber 30 Lower partition wall 14 and upper partition wall at an inner position of the second gas pipe so as to connect the plurality of second gas pipes 62 erected penetrating, the lower connection chamber 30 and the combustion exhaust gas discharge chamber 40 By providing a plurality of third gas pipes 63 erected through 17, water is heated using the combustion exhaust gas generated in the boiler.

A disk-shaped lower partition wall 14 is mounted at a lower position in the cylindrical water pipe 11 through which water passes, and a combustion exhaust gas introducing chamber 20 facing the gas inlet 15 formed at the lower end position of the water pipe 11 is formed. ing.
Further, the lower connecting chamber 30 partitioned with respect to the combustion exhaust gas introducing chamber 20 is formed by closing the lower surface side of the lower partition wall 14 with the conical lid portion 16. The lower connection chamber 30 is closed by the conical lid portion 16 and is thus configured as a conical space that is convex toward the combustion exhaust gas introduction chamber.

  A disk-shaped upper partition wall 17 is mounted at an upper position in the water pipe 11, and an annular partition wall 18 is mounted between the upper partition wall 17 and the top surface of the water pipe 11. A combustion exhaust gas discharge chamber 40 facing the gas exhaust port 19 formed at a position and an upper annular connection chamber 50 surrounding the combustion exhaust gas discharge chamber 40 are formed.

According to the above structure, in the plurality of gas pipes 61, 62, 63, the combustion exhaust gas introduced from the bottom side of the water pipe 11 is folded back at the upper portion of the water pipe 11 and flows downward, and is further folded back at the lower portion of the water pipe 22 and flows upward 11. Heat the water in the water pipe 11 by heat exchange when flowing out from the upper surface side.
Since the plurality of first gas pipes 61 and the plurality of second gas pipes 62 are arranged in an annular row in the water pipe 11 with the total number and cross-sectional areas equalized, the number of gas pipes that can be arranged is It may be limited. For example, in the above-described example, the number of the second gas pipes 62 that can be arranged in a line outside the annular partition wall 18 is limited, and accordingly the number of the first gas pipes 61 and the third gas pipes 63 Is decided. Since the first gas pipes 61 are also arranged in a line, the arrangement density is lower than that of the second gas pipes 62. For this reason, there has been a problem in that the number of arrangement is maximized to interfere with effective heating.

  The present invention has been proposed in view of the above-described circumstances, and provides an economizer with a structure capable of efficiently heating water by installing the maximum number of gas pipes and efficiently performing inspection and cleaning. The purpose is to

In order to achieve the above object, the present invention (claim 1) relates to an economizer which heats water by combustion exhaust gas generated in a boiler,
A cylindrical water pipe (11) having an inlet (12) and an outlet (13) formed on the side, through which the water passes;
A flue gas introducing pipe (20) connected to the lower end position of the water pipe (11) via a dividing wall (lower dividing wall 14);
And a flue gas exhaust pipe (40) connected to the upper end position of the water pipe (11) via a partition wall (upper partition wall 17),
The combustion exhaust gas introduction pipe is divided into a combustion exhaust gas introduction chamber (A) facing the gas introduction port (combustion gas introduction port 15) and a lower combustion exhaust gas passage chamber (B), and the combustion exhaust gas discharge pipe has a gas exhaust port Divided into a combustion exhaust gas chamber (C) facing the (combustion gas exhaust port 19) and an upper combustion exhaust gas passage chamber (D),
And a plurality of first gas pipes (61) erected in the water pipe through the partition wall so as to connect the combustion exhaust gas introduction chamber (A) and the upper combustion exhaust gas passage chamber (D) ,
A plurality of second gas pipes (62) erected in the water pipe penetrating the partition wall so as to connect the upper combustion exhaust gas passage (D) and the lower combustion exhaust gas passage (B) And a plurality of third gas pipes (63) erected in the water pipe through the partition wall so as to connect the lower combustion exhaust gas passage chamber (B) and the combustion exhaust gas discharge chamber (C). Together with
The connection between the water pipe (11) and the combustion exhaust gas introduction pipe (20) and the combustion exhaust gas discharge pipe (40) is achieved by the flange portions (11a, 11b) of the water pipe (11) and the combustion exhaust gas introduction pipe (20) And each flange part (20a, 40a) of the said combustion exhaust gas discharge pipe (40) is made to oppose, and it is comprised so that attachment or detachment is possible, The said combustion exhaust gas introduction pipe (20) and the said combustion exhaust gas discharge with respect to the said water pipe (11). It is characterized in that both ends of the first gas pipe (61), the second gas pipe (62) and the third gas pipe (63) can be exposed when the pipe (40) is removed.

The claim 2 is the economizer according to claim 1
The combustion exhaust gas introduction chamber (A) is an area dividing the combustion exhaust gas introduction pipe (20) into three in a horizontal plane, and the combustion exhaust gas discharge chamber (C) is an area dividing the combustion exhaust gas discharge pipe (40) into three in a horizontal surface And are each characterized by being formed.

A third aspect of the invention is the economizer of the second aspect, wherein
The combustion exhaust gas introduction chamber (A) and the combustion exhaust gas discharge chamber (C) are characterized by being fan-shaped in the horizontal plane.

A fourth aspect of the present invention is the economizer according to the first aspect, wherein
The sum of the cross-sectional areas of the first gas pipe (61), the sum of the cross-sectional areas of the second gas pipe (62), and the sum of the cross-sectional areas of the third gas pipe (63) are equal. It is characterized by

A fifth aspect of the invention is the economizer of the fourth aspect, wherein
The number of the first gas pipes (61), the number of the second gas pipes (62), and the number of the third gas pipes (63) are equal to each other.

A sixth aspect of the invention is the economizer of the first aspect, wherein
The inlet (12) is formed at a lower position on the side surface of the water pipe, and the outlet (13) is formed at an upper position on the side surface of the water pipe.

A seventh aspect of the invention relates to the economizer according to any one of the first to sixth aspects, wherein
The water pipe is characterized by comprising a pressure water container.

According to the economizer of claim 1, by arranging the plurality of gas pipes (61, 62, 63) erected for circulating the combustion exhaust gas in the water pipe (11), the gas can be supplied into the water pipe. Water is heated efficiently around the gas pipe.
Further, the combustion exhaust gas introduction pipe (20) and the combustion exhaust gas discharge pipe (40) are removed from the water pipe (11), and the first gas pipe (61), the second gas pipe (62) and the third gas pipe ( By making each opening at both ends of the above 63) face, inspection and cleaning of the inside of each gas pipe can be easily performed.

  According to the economizer of the second and third aspects, the first gas pipe (61), the second gas pipe (62), and the second gas pipe (62) are arranged in a region (fan-shaped portion) where the water pipe (11) is divided into three in the horizontal plane. Since the gas pipe (63) of No. 3 can be arranged without considering the arrangement position of the other gas pipes, it is possible to install many gas pipes in the fan-shaped portion.

  According to the fourth aspect, by equalizing the total number of the cross sectional areas of the first gas pipe (61), the second gas pipe (62), and the third gas pipe (63), When the combustion exhaust gas flows into the gas pipe, the generation of resistance can be suppressed to facilitate the flow.

  According to the fifth aspect, by equalizing the numbers of the first gas pipe (61), the second gas pipe (62), and the third gas pipe (63), the first gas pipe, The second gas pipe and the third gas pipe can have the same size.

  According to the sixth aspect, by forming the inlet (12) at the lower position and the outlet (13) at the upper position, the heated water can be easily discharged.

  According to the seventh aspect, the heated water can be brought to a temperature of 100 ° C. or more by constructing the water pipe (11) with a pressure water container.

It is a front explanatory view of the economizer of the present invention. It is side explanatory drawing of the economizer of this invention. It is a plane explanatory view of the economizer of the present invention. It is a bottom explanatory view of the economizer of the present invention. It is a model figure for demonstrating the flow direction of the combustion exhaust gas which flows through the some gas pipe installed in the water pipe. The cross section of an economizer is shown, (a) is a cross-sectional explanatory view of a combustion exhaust gas discharge pipe, (b) is a cross-sectional explanatory view of a water pipe, and (c) is a cross-sectional explanatory view of a combustion exhaust gas introduction pipe. It is a longitudinal cross-section explanatory drawing of the economizer which the present inventor proposed. FIG. 7 is a cross-sectional explanatory view taken along line II-II of FIG. 7; It is III-III line | wire cross-section explanatory drawing of FIG. It is structure explanatory drawing which shows the structure of the conventional economizer.

An example of an embodiment of the economizer according to the present invention will be described with reference to FIGS. 1 to 6. In FIG. 1 to FIG. 6, parts having the same configuration as in FIG. 7 and FIG.
The economizer heats the water by the combustion exhaust gas generated in the boiler, and as shown in FIG. 1, with respect to the cylindrical water pipe (water container) 11, the inlet 12 and the outlet 13 are sided. Three are formed at a time. The inlets 12 are formed at 120 degree intervals at lower positions on the side of the water pipe, and the outlets 13 are formed at 120 degree intervals at upper positions on the side of the water pipe, and the water (water supply) supplied from the three inlets 12 is It is configured to be warmed and risen inside the water pipe and to flow out (drain) from the three outlets 13.

A disk-shaped lower partition wall 14 is mounted at a lower end position in the cylindrical water pipe 11 through which water passes, and a combustion exhaust gas introduction pipe 20 having the same diameter as the water pipe 11 is a flange so as to cover the lower partition wall 14 The parts (flange part 11a and flange part 20a) are oppositely connected and fixed. The combustion exhaust gas introduction pipe 20 is closed by a bottom cover 21, and a combustion gas introduction port 15 is connected to the bottom cover 21 (FIG. 1, FIG. 2, FIG. 4).
The connection between the water pipe 11 and the combustion exhaust gas introduction pipe 20 makes the flange portion 11a formed on the water pipe 11 face the flange portion 20a formed on the combustion exhaust gas introduction pipe 20, and the plurality of bolts 71 and nuts 72 desorb them. It is linked and fixed possible.

  The inside of the combustion exhaust gas introduction pipe 20 is divided into a combustion exhaust gas introduction chamber A facing the combustion gas introduction port 15 by the vertical lower partition wall 22 and a lower combustion exhaust gas passage chamber B (FIG. 5). By forming the vertical lower partition wall 22 with a bent piece bent at an angle of 120 degrees at the center, the combustion exhaust gas introduction chamber A is divided into 1/3 area in the horizontal plane with respect to the combustion exhaust gas introduction pipe 20 ing.

A disk-shaped upper partition wall 17 is mounted at the upper end position in the water pipe 11, and the combustion exhaust gas discharge pipe 40 having the same diameter as the water pipe 11 is flanged to each other (flange part 11b and The flanges 40a) are oppositely connected and fixed. The combustion exhaust gas discharge pipe 40 is closed by an upper surface cover 41, and a combustion gas discharge port 19 is connected to the upper surface cover 41 (FIGS. 1 to 3).
Connection between the water pipe 11 and the combustion exhaust gas discharge pipe 40 makes the flange portion 11 b formed in the water pipe 11 and the flange portion 40 a formed in the combustion exhaust gas discharge pipe 40 face each other, and is desorbed by a plurality of bolts 71 and nuts 72. It is linked and fixed possible.

  The combustion exhaust gas discharge pipe 40 is divided into a combustion exhaust gas discharge chamber C facing the combustion gas discharge port 19 by the vertical upper partition wall 42 and an upper combustion exhaust gas passage chamber D (FIG. 5). By forming the vertical upper partition wall 42 with a bent piece bent at an angle of 120 degrees at the center, the combustion exhaust gas discharge chamber C is divided into 1/3 area in the horizontal plane with respect to the combustion exhaust gas discharge pipe 40 ing.

In the water pipe 11, a plurality of gas pipes are disposed in order to circulate the combustion exhaust gas.
As shown in FIG. 6, the gas pipe penetrates the lower partition wall 14 and the upper partition wall 17 and connects the combustion exhaust gas introduction chamber A and the upper combustion exhaust gas passage chamber D to one-third of the horizontal plane in the water pipe 11 The upper combustion exhaust gas passage chamber D and the lower combustion exhaust gas passage chamber B are connected through the plurality of first gas pipes 61 erected in the area portion (fan shape), the lower partition wall 14 and the upper partition wall 17 Lower combustion exhaust gas passage chamber through the plurality of second gas pipes 62 erected on a 1/3 area portion (fan shape) of the horizontal surface of the water pipe 11 and the lower partition wall 14 and the upper partition wall 17 to In order to connect B and the combustion exhaust gas discharge chamber C, a plurality of third gas pipes 63 are provided standing on a 1/3 area portion (sector shape) of a horizontal surface of the water pipe 11. That is, in the example of FIG. 6, 31 gas pipes are arranged in each fan-shaped part (each area divided by the dotted line in FIG. 6B) in which the water pipe 11 is sectioned in a horizontal plane.

That is, 31 first gas pipes 61 are disposed in the fan-shaped column portion of water pipe 11 and are configured to connect combustion exhaust gas introduction chamber A and upper combustion exhaust gas passage chamber D, and from gas introduction port 15 The flue gas led to the flue gas introduction chamber A moves upward through the plurality of first gas pipes 61 ([1] to [2] in FIG. 5), and is once led to the upper flue gas passage chamber D. .
The second gas pipe 62 is arranged at 31 fan-shaped column portions of the water pipe 11 and configured to connect the upper combustion exhaust gas passage chamber D and the lower combustion exhaust gas passage chamber B, thereby making the upper combustion exhaust gas The flue gas from the passage chamber D moves downward through the plurality of second gas pipes 62 ([3] to [4] in FIG. 5), and is once led to the lower flue gas passage chamber B.
The third gas pipe 63 is arranged at 31 fan-shaped column parts of the water pipe 11 and configured to connect the lower combustion exhaust gas passage chamber B and the combustion exhaust gas discharge chamber C, thereby passing the lower combustion exhaust gas passage. The combustion exhaust gas from the chamber B moves upward through the plurality of third gas pipes 63 ([5] to [6] in FIG. 5), and is exhausted from the gas exhaust port 19 via the combustion exhaust gas chamber C. Ru.

According to the above-described configuration, each gas pipe group arranged in the fan-shaped portion in the horizontal plane can be freely arranged without being restricted by the arrangement position of the other gas pipes. It becomes possible to install the number of gas pipes.
As a result, by arranging many gas pipes, the gas flow path is narrowed to increase the gas velocity, and by increasing the number, indirect heating of the flue gas and water in the water pipe is performed without reducing the heat transfer area. It is possible to efficiently heat the water in the water tank.

  The first gas pipe 61, the second gas pipe 62, and the third gas pipe 63 are provided in the same number (31), respectively, and the diameters of the respective gas pipes are the same, and the total number of the flow paths is the same. The areas are formed to be the same. This is to reduce the resistance generated when the combustion exhaust gas moves from the first gas pipe 61 to the second gas pipe 62 and from the second gas pipe 62 to the third gas pipe 63.

Further, the upper end and the lower end of the water pipe are configured to be connected with each other by the flange portions, and the first gas pipe 61, the second gas pipe 62, and the third gas pipe 63 are easily removable by the flange portion. The respective openings at both ends of the can be viewed from above and below.
By making each opening at both ends of the first gas pipe 61, the second gas pipe 62, and the third gas pipe 63 face, inspection in the gas pipe is facilitated, and high-pressure cleaning water is used from this part Thus, the interior of the gas pipe can be easily cleaned.

According to the above-described structure of the economizer, the high temperature combustion exhaust gas introduced from the gas introduction port 15 flows upward from the combustion exhaust gas introduction chamber A through the gas pipe 61 and flows to the upper combustion exhaust gas passage chamber D.
Subsequently, the combustion exhaust gas bounces back in the upper combustion exhaust gas passage chamber D, moves downward through the second gas pipe 62, and flows to the lower combustion exhaust gas passage chamber B.
The combustion exhaust gas bounces back in a collision, moves upward through the third gas pipe 63, flows to the combustion exhaust gas discharge chamber C, and is discharged from the combustion exhaust gas outlet 19.
Further, the water supplied from the inlet 12 of the water pipe 11 moves up from the bottom of the water pipe 11 while coming into contact with the surroundings of the gas pipes 61, 62, 63 and flows out from the outlet 13.

According to the above-mentioned economizer, a plurality of gas pipes (the first gas pipe 61, the second gas pipe 62, the third gas pipe 63) erected for circulating the combustion exhaust gas are disposed in the water pipe 11. By arranging, the water supplied into the water pipe 11 is efficiently heated around the gas pipe.
That is, since the gas pipe is disposed in the water pipe 11, the volume of the water pipe 11 can be made sufficiently large, so the amount of retained water (for example, 200 to 400 liters, preferably 300 liters or more) can be increased. Even if the amount of supplied water increases, the temperature drop of the water due to the increase can be suppressed, and there is an effect that sufficient heating (possible to about 100 ° C.) can be maintained.

Further, since the combustion exhaust gas is not directly led into the water pipe 11 and flows only in each gas pipe, the contamination by the combustion exhaust gas does not adhere to the water pipe 11.
Further, since the combustion exhaust gas introduction pipe 20 and the combustion exhaust gas discharge pipe 40 are respectively connected to the upper end and the lower end of the water pipe 11 via the flange portion, both can be easily detached at the flange portion by removing the bolt 71 and the nut 72 It is possible to easily clean the inside of the gas pipe so that each end of the first gas pipe 61, the second gas pipe 62 and the third gas pipe 63 can be faced.

  The water pipe 11 of the above-mentioned economizer consists of a water container in which atmospheric pressure is applied to the water surface of the holding water and the water warmed inside the water pipe flows out (drains) from the outlet 13. By holding the water level by valve control, it may be configured by a pressure water container in which water is stored at a constant pressure different from the atmospheric pressure. When the water pipe 11 is used as a pressure water container, the heated water can be raised to about 150 ° C., which is 100 ° C. or more.

11 ... water pipe (pressure water container)
11a, 11b: Flange portion 12: Inlet 13: Outlet 14: Lower partition wall 15: Combustion exhaust gas inlet 17: Upper partition wall 19: Combustion exhaust gas outlet 20: Combustion exhaust gas introduction pipe (combustion exhaust gas introduction chamber)
20a ... flange portion 40 ... combustion exhaust gas discharge pipe (combustion exhaust gas discharge chamber)
DESCRIPTION OF SYMBOLS 40a ... Flange part 61 ... 1st gas pipe 62 ... 2nd gas pipe 63 ... 3rd gas pipe A ... Combustion exhaust gas introduction chamber B ... Lower combustion exhaust gas passage chamber C ... Combustion exhaust gas discharge chamber D ... Upper combustion exhaust gas passage Room

Claims (7)

In the economizer, which heats water by the flue gas generated in the boiler,
A cylindrical water pipe having an inlet and an outlet formed on the side, through which the water passes;
A flue gas inlet pipe connected to the lower end position of the water pipe via a partition wall;
And a flue gas exhaust pipe connected to the upper end position of the water pipe via a partition wall,
The flue gas introduction pipe is divided into a flue gas introduction chamber facing the gas inlet and a lower flue gas passage chamber, and the flue gas discharge pipe is divided into a flue gas discharge chamber facing the gas outlet and an upper flue gas passage chamber. Sectioned,
A plurality of first gas pipes which are provided in the water pipe so as to penetrate the partition wall so as to connect the combustion exhaust gas introduction chamber and the upper combustion exhaust gas passage chamber;
A plurality of second gas pipes, which are provided upright in the water pipe so as to communicate the upper combustion exhaust gas passage chamber and the lower combustion exhaust gas passage chamber, are disposed in the water pipe, the lower combustion exhaust gas passage chamber, and A plurality of third gas pipes which are installed in the water pipe so as to penetrate the partition wall so as to connect with the combustion exhaust gas discharge chamber;
Together with
The connection between the water pipe and the combustion exhaust gas introduction pipe and the combustion exhaust gas discharge pipe is configured to be detachable with the flanges of the water pipe facing the flanges of the combustion exhaust gas introduction pipe and the combustion exhaust gas discharge pipe. In a state where the combustion exhaust gas introduction pipe and the combustion exhaust gas discharge pipe are removed from the water pipe, both ends of the first gas pipe, the second gas pipe and the third gas pipe can be exposed Features economizers.   The combustion exhaust gas introduction chamber according to claim 1, wherein the combustion exhaust gas introduction chamber has an area dividing the combustion exhaust gas introduction pipe into three in the horizontal plane, and the combustion exhaust gas discharge chamber divides the combustion exhaust gas discharge pipe into three areas in the horizontal surface. Economizer.   The economizer according to claim 2, wherein the combustion exhaust gas introduction chamber and the combustion exhaust gas discharge chamber are fan-shaped in a horizontal plane.   The economizer according to claim 1, wherein the sum of the cross-sectional areas of the first gas pipe, the sum of the cross-sectional areas of the second gas pipe, and the sum of the cross-sectional areas of the third gas pipe are equal.   5. The economizer according to claim 4, wherein the number of first gas pipes, the number of second gas pipes, and the number of third gas pipes are equal.   The economizer according to claim 1, wherein the inflow port is formed at a water pipe side surface lower position, and the outflow port is formed at a water pipe side surface upper position.   The economizer according to any one of claims 1 to 6, wherein the water pipe is constituted by a pressure water container.

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