JPS609527Y2 - boiler - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a boiler (woodwind type, once-through type, etc.) in which a fluid passage is provided between a pair of ice chambers and surrounding a combustion chamber.

An example of a conventional boiler of this kind is shown in FIGS. 1 and 2. Water pipes 3 and 4 are connected between an annular upper water chamber 1 and a lower water chamber 2.
are arranged in a double cylindrical shape, forming a combustion chamber 5 in the center, and a flue 6 and a flue 7 are formed in the arrangement as shown in FIG. and reaches the flue 10.

11 is a burner.

Adjacent water pipes 3 or 4 are in close contact with each other to form a continuous spiral wall as shown in FIG.

Since the upper and lower ends of the water pipe 3 or 4 are formed to have a narrow diameter and are connected to the upper water chamber 1 or the lower water chamber 2, a gap is created between the adjacent small diameter portions.

This gap is filled with casters 12, and the above-mentioned spiral wall made of wood pipe blocks the space on both sides.

13 is a bending part to avoid thermal stress, and 14 is a caster at the bottom of the hearth.

When operating this boiler, when the central burner 11 is fired, the inside of the water pipe 3 facing the combustion chamber 5 is heated by radiation and convection of the combustion gas, and the gas passes through the flue 7 from the flue population 6. The water pipes 3 on both sides of the flue 7 due to combustion gas,
4 is heated, and the water pipe 4 is heated while passing through the outermost flue 9.

At this time, the relatively high-temperature inner water pipe 3 serves as a rising pipe, and the relatively low-temperature outer water pipe 4 serves as a downcomer pipe, through which water circulates.

In order to operate such a boiler more effectively, further improvement in efficiency is desired.

There are various methods for improving efficiency, one of which is increasing the effective heat transfer area.

This is because generally speaking, the smaller the amount of heat transferred per unit heat transfer area, the better the thermal efficiency, but increasing the transfer area increases the overall size of the boiler, which is a disadvantage in terms of installation area, price, etc. was there.

In addition, in this method, particles of fuel oil discharged from the burner 11 enter the flow path 15 (FIG. 1) near the burner 11.
It enters the flue 7 as large particles without being completely combusted.

If the gas enters the flue 6 from the flow path 16 near the bottom of the combustion chamber 5, it will be completely combusted, so there is no problem, but if the gas containing the incomplete combustion particles mentioned above enters the flue 7, it will be cooled and will not burn. If it is discharged as is, the amount of dust will increase.

To prevent this, it is necessary to improve the mixing near the burner 11 to ensure complete combustion within the combustion chamber 5.

This mixing can reduce the amount of dust.

By increasing the heat transfer area without changing the external dimensions of the boiler,
In order to improve these shortcomings, some structures have been seen in which a flue is installed inside the wood pipe to heat the wood pipe from the inside and outside. Heating promotes the overall rise of the fluid, disrupting the orderly circulation of the fluid due to upward and downward flows, and the liquid level becomes unstable.

Therefore, when there is a fluctuation in the steam consumption on the load side, the liquid level fluctuates violently and the liquid level often reaches the upper or lower limit. There were drawbacks that hindered it.

The present invention eliminates the above-mentioned drawbacks of conventional ones and provides a boiler that can operate stably even if there are fluctuations in steam consumption on the load side, with little liquid level fluctuation and avoiding useless operation shutdowns. The purpose is to

In the present invention, an annular first ice chamber and a second ice chamber are arranged in parallel, and the combustion chamber wall and flue are connected concentrically around the burner center line between the first and second water chambers. a first flue is formed between the combustion chamber wall and the flue wall, and a first flue is formed between the combustion chamber wall and the flue wall; a second flue is formed between the wall and the casing, the combustion chamber wall and the flue wall each having a fluid passage connecting the first water chamber and the second ice chamber; and each of the fluid passages in the flue wall has a smoke tube therein, and the inlet and outlet of the flue tube are provided at opposite ends, and the outlet of the flue tube in the combustion chamber wall and the flue wall are connected to each other. The inlet of the smoke pipe is provided on the opposite side, and the combustion gas flows into the smoke pipe on the wall of the combustion chamber.
configured to be led to the outside through the first flue, the smoke pipe of the flue wall, and the second flue, and a part of the flue wall,
This boiler is characterized by having a smokeless pipe area where no smoke pipes are provided.

To explain the present invention using the drawings as an embodiment, in FIGS. 3 and 4, an annular first water chamber, an upper water chamber 1, and a second annular water chamber, a lower water chamber 2, are arranged in parallel. The combustion chamber wall 17 (formed by closely arranging the water pipes 3) and the flue are arranged horizontally and concentrically surrounding the center line of the burner 11 between the upper water chamber 1 and the lower water chamber 2. The wall 18 (formed by closely arranging the water pipes 4) is arranged in a double manner to form a combustion chamber 5 with a vertical peripheral wall inside the combustion chamber wall 17, and the combustion chamber wall 17 and the flue A first flue 7 is formed between the flue wall 18 and the casing 8, a second flue 9 is formed between the flue wall 18 and the casing 8, and a second flue 9 is formed between the flue wall 18 and the casing 8.
7 and the flue wall 18 are respectively provided with a water pipe 3 and a water pipe 4 as fluid passages connecting the upper water chamber 1 and the lower water chamber 2. each has a smoke pipe 19.23 inside, the inlet 20.24 and the outlet 21.25 of the smoke pipe 19.23 are provided on the opposite side, and the outlet 21 of the smoke pipe 19 in the combustion chamber wall 17, The inlet 24 of the flue pipe 23 of the flue wall 18 is provided on the opposite side, so that the combustion gas flows through the flue pipe 19 of the combustion chamber wall 17, the first flue 7, the flue pipe 23 of the flue wall 18, and the second flue 9. It is configured to be led to the outside through the

The entire length of the water pipes 3 or 4 is welded together, or they are joined together with a partial bead.

The flue 6 shown in FIG. 2 is not provided.

The upper and lower ends of the water pipes 3 and 4 are buried and sealed with casters 12.

Some of the water pipes 4 forming the flue wall 18 are
A smokeless pipe region 30 is provided in a part of the flue wall 18 without a smoke pipe 23 inside.

During operation, when the central burner 11 is fired, the inner side of the water pipe 3 is heated by radiation and convection heat.

At this time, the flame does not come into direct contact with the water pipe 3, which is the inner circumferential wall of the combustion chamber wall 17.

The combustion gas passes through the lower inlet 20 and the smoke pipe 19, heats the water in the water pipe 3 from inside, enters the upper end of the flue 7 through the outlet 21, descends through the flue 7, and reaches the outer surface of the water pipe 3. , heats the inner surface of the water pipe 4 and enters the smoke pipe 23 from the inlet 24 at the lower end, heats the water in the water pipe 4 from the inside, enters the flue 9 from the outlet 25, and heats the water on the outside of the wood pipe 4. Flue 10 while heating the surface
and is discharged.

The present embodiment is constructed and operates as described above, and since the area of the smoke pipe 19.23 among the water pipes 3 and 4 is increased, the amount of heat transferred per unit area is small, and the thermal efficiency is improved. This does not involve an increase in the overall dimensions of the boiler.

Moreover, the outlet of the combustion gas from the combustion chamber 5 is located on the opposite side of the burner 11, and has a structure that allows only the combustion gas to flow out after complete combustion. The inner surface is vertical and is heated by radiation and convection, with little heating by direct contact with the flame, so there is no need for particularly intense mixing to ensure complete combustion, and the generation of dust can be suppressed.

Furthermore, since a part of the flue wall 18 is a smokeless pipe area 30, the temperature of the liquid in the water pipe 4 in this part is lower than that in other parts of the flue where precipitation mainly occurs. Among the water pipes 4 of the wall 18, a rain flow path is ensured in which precipitation is particularly promoted, fluid circulation becomes smooth, and fluctuations in the liquid level can be reduced even if there are fluctuations in steam consumption on the load side. can.

Therefore, it is possible to prevent the liquid level from reaching the upper and lower limits more than necessary, avoid unnecessary stoppages, and perform stable operation.

FIG. 5 shows another embodiment, in which so-called return combustion is performed.

That is, the burner 11 is of a long frame type for return combustion and is mounted slightly downward, and the combustion gas once hits the bottom, reverses itself, and rises along the periphery of the combustion chamber.

Further complete combustion and NOx reduction can be expected through return combustion.

In this case, inlets 20, 24, outlets 21, 25, flue 1
The position of 0 is upside down from that shown in FIG.

FIG. 6 shows another embodiment, showing a cross-sectional view equivalent to FIG.
6 and an outer cylinder 27, and an inner cylinder 28 and an outer cylinder 29, and the space between the inner cylinder 26 and the outer cylinder 27 and the space between the inner cylinder 28 and the outer cylinder 29 are fluid passages. This is the result.

In the above embodiments, an example of a vertical wood tube type boiler is shown, but it can also be applied to a once-through type boiler, and it can also be applied to a horizontal type boiler to achieve the same effect. can.

In the case of a horizontal type, it is preferable to tilt it slightly from horizontal.

This invention partially promotes precipitation of liquid in the boiler.
A rain flow path is secured to ensure smooth liquid circulation, and the liquid level fluctuates less even when the steam consumption on the load side changes.
It is possible to provide a boiler that operates stably and avoids useless stoppages due to large fluctuations in the liquid level, which is extremely effective in practice.

[Brief explanation of the drawing]

Figure 1 is a vertical cross-sectional view of an example of a conventional boiler, and Figure 2 is its I
-I line sectional view, FIG. 3 is a longitudinal sectional view of the embodiment of the present invention,
FIG. 4 is a cross-sectional view taken along the line ■--■, FIG. 5 is a vertical cross-sectional view of another embodiment, and FIG. 6 is a cross-sectional view of another embodiment. 1... Upper ice chamber, 2... Lower water chamber, 3
, 4... Water pipe, 5... Combustion chamber, 6...
... Flue entrance, 7 ... Flue, 8 ...
・Casing, 9.10・Curve・Flute, 11...
Burner, 12... Caster, 13...
・Flexible part, 14... Caster, 15, 16
...Flow path, 17... Combustion chamber wall, 18.
... Flue wall, 19 ... Smoke pipe, 20 ...
...Inflow port, 21...Outflow port, 23...
...Smoke pipe, 24...Inlet, 25...
Outlet, 26... Inner cylinder, 27... Outer cylinder, 28... Inner cylinder, 29... Outer cylinder, 30
...Smokeless pipe area.

Claims (1)

[Scope of utility model registration request] A ring-shaped first water chamber and a second ice chamber are arranged in parallel, and between the first ice chamber and the second ice chamber, a combustion chamber wall and a flue wall are connected concentrically around the burner center line. to form a combustion chamber with a vertical peripheral wall inside the combustion chamber wall, a first flue between the combustion chamber wall and the flue wall, and a first flue between the flue wall and the casing. a second flue is formed between the combustion chamber wall and the flue wall, each having a fluid passage connecting the first water chamber and the second water chamber, and the fluid passage of the combustion chamber wall and the smoke Each of the fluid passages in the channel wall has a smoke tube therein, and the inlet and outlet of the flue tube are provided on opposite sides, and the outlet of the flue tube in the combustion chamber wall and the flow of the flue tube in the flue wall are connected to each other. An inlet is provided on the opposite side, and is arranged such that the combustion gas is guided to the outside through the smoke pipe in the combustion chamber wall, the first flue, the smoke pipe in the flue wall, and the second flue, and A boiler characterized by having a flue-free area in which no smoke pipe is installed in a part of the flue wall.