JPS63217112A - Solid fuel burning equipment - Google Patents

Abstract

PURPOSE:To provide complete combustion in a solid fuel combustion device using lime and the like as a fuel for indirect heating furnace by a method wherein aeration holes are provided near a grid surface of a side wall of a combustion chamber having a top net, a grid is placed over the grid surface and a suction port is provided to communicate with a thermal conducting pipe at the grid surface. CONSTITUTION:A suction blower 17 is operated to ignited a burner, resulting in that fuel on a grid 11 is ignited and decomposed gas generated by combustion is partially mixed with air and directed toward a net 3. The decomposed gas reaching the net 3 descends the inner surface of a side wall 7 and flows down into a lower part of the grid 11 from between the fuels. Gas reaching the grid 11 is heated under primary combustion at the grid 11 and at the same time dispersed with and mixed with air coming from aeration holes 9 into the upper surface of a grid 10 and then ignited. The combustion gas is sucked from the gas suction port 15 under operation of a blower 17 and then guided to a thermal radiation pipe 16. With this arrangement, it is possible to make a complete combustion.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention mainly relates to a combustion device for burning solid fuels such as wood, coal, and recent pellet fuel. The present invention relates to a solid fuel combustion system that can be used as a combustion device for wind, hot water, etc., and also as an indirect heating device for boilers, heat exchangers, etc.

When using wood as fuel, use firewood or sawn residue cut into short pieces.

<Conventional technology and problems> (1) Regarding general combustion equipment, whether it is hot air heating, incineration boiler (vertical boiler), etc., or combustion over a grate or combustion over an electric board, these In all conventional solid combustion devices, the combustion chamber goes from combustion to the smoke exhaust section, where a one-sided flow is formed, and the burned material is exhausted as is. Of course, various considerations have been made regarding the supply of air to the combustion zone to ensure complete combustion.

However, it is difficult to diffuse and supply air to the combustion center area, and air shortages inevitably occur. Therefore, incomplete combustion is also likely to occur.

('2) The conventional combustion device closest to the present invention is disclosed in Japanese Patent Application Laid-Open No. 59-22150, and has a structure as shown in Fig. 4. In other words, the combustion chamber An intake pipe 20 is provided from the upper part 19 toward the combustion chamber, and combustion gas rising through the intake pipe 20 is mixed with a descending air flow to improve combustion efficiency.

However, in this combustion device, the combustion zone is wide and rises, and the air supply from the top does not reach the necessary parts sufficiently due to resistance from the fuel. Oxygen cannot diffuse into the central region because it is swept away by the upward force of the widespread flame.

Means for Solving the Problems> Therefore, the present invention forms a ceiling over the entire upper part of the combustion chamber to create a space that encloses the inside of the combustion chamber in one to one area. A large number of ventilation holes are provided around the side walls of the combustion chamber, and a grate is installed at an appropriate height from the grate surface in the center of the combustion chamber. The gas suction port for sucking the combustion gas on the opposite side is connected to the heat transfer tube.

<Function> In such a configuration, solid fuel such as wood or coal is placed on the combustion chamber grate-F side and the fire bed surface! ``From the bottom of the grate,
When igniting with a burner, etc., due to combustion on the top surface of the grate, decomposed gases (volatile components) such as water vapor, HC, and Co are generated from the fuel in the adjacent vicinity due to the heat of combustion.
Rise. These decomposed gases that have risen are guided from the top 11 of the combustion chamber to the inner surface of its side wall, descend along this side wall, and flow from the grate surface to below the grate. At this time, the air flowing in from the ventilation holes provided around the side walls crawls over the large floor surface,
The combustion gas is mixed with the decomposed gas mentioned above under the grate and combusted, and the combustion gas is sucked through the gas suction port and reaches the heat exchanger tube, where the heat is dissipated.

<Example> Hereinafter, an example in which the present invention is applied to a combustion device for a heater in a cultivation house or the like will be described.

FIG. 1 is a vertical sectional view, FIG. 2 is a horizontal sectional view, and FIG. 3 is an explanatory diagram of the operation of the present invention.

First, in FIG. 1, reference numeral 1 denotes a cylindrical body, with a combustion chamber 2 inside. This body 1 is installed in a vertical state, has a ceiling 3 on the top, and has an enclosed cavity inside.

That is, the combustion chamber 2 is surrounded by the ceiling 3 and the body 14 (hereinafter referred to as the side wall 7) at the top and bottom and on all four sides. In addition,
The top #13 is not made of plywood at all, but is equipped with a fuel inlet 5 for injecting fuel into the combustion chamber 2.
In this case, the M6 is able to take off its neck freely.

Of course, during combustion, M6 is attached and the ceiling 3 is closed.

A lower edge 8 of a side wall 7 surrounding the combustion chamber 2 is provided with a large number of ventilation holes 9 all around the circumference.

These ventilation holes 9 are provided as close as possible to a grate surface 10, which will be described later. This is to make the airflow flowing in from the vent 9 follow the grate surface 10 as much as possible and reach under the grate in the center of the combustion chamber.

This is because the closer the flow of incoming air is to the grate surface 10, the better and necessary the effects of the present invention are.

The size of these ventilation holes 9 is usually 2.
0φ~40φI is suitable, and the hole spacing is 60-20
Approximately 01111 is good.

Next, a grate 11 is installed in the center of the combustion chamber 2 at a required height above the grate surface 10. This grate 11
Needless to say, it is provided with a gap 12 so that air can pass from the bottom surface to the top surface, but in the case of the present invention, it has a framework structure in the form of steps or spiral steps as shown in the figure, and there is a gap 12 on the inside of the bottom surface. A conical space 13 is formed.

This is because when the cracked gas is combusted below the grate 11, the combustion space is large, and this combustion is stored inside the combustion chamber as much as possible, and the radiated heat is transferred to the upper part (the primary combustion part on the grate). This is to make it work.

Note that the grate 11 is supported on the grate surface 10 by a plurality of legs 14.

Further, below the grate 11, a gas suction port 15 for sucking combustion gas into the grate surface 10 is provided facing downward.

The gas suction port 15 is guided outside the furnace under the large floor and connected to the heat exchanger tube 1G and the suction blower 17 outside the furnace. Note that this gas suction port 15 is normally 100φ.
~200φ is appropriate for accumulating gas combustion in the combustion chamber 2, and is also appropriate for removing h1 when ash remains.

The above-mentioned suction floor 17 is used to circulate the decomposed gas and incompletely combusted gas in the combustion chamber 2, to take in outside air from the side wall vent 9, and to mix this outside air and the decomposed gas under the grate 11. , furthermore, is necessary for the extraction of combustion gases from the combustion chamber 2. Of course, the combustion speed can be adjusted by adjusting the air volume of the suction blower 17.

Reference numeral 18 shown on the side wall 7 of the combustion chamber 2 is a window for taking out residual waste such as ash, which is of course closed during combustion.

<Operation in this embodiment> The lid 6 of the ceiling 3 of the combustion chamber 2 is removed, and short pieces of wood, coal, etc. are supplied through the combustion inlet 5 and deposited on the fire bed surface 11 and the upper surface of the grate.

It is preferable that the amount of fuel m to be added is enough to fill 90% of the combustion chamber 2.

In addition, when supplying these fuels, the fuel reaches appropriate places on the grate surface 10 from outside the furnace and below the grate 11, making the fuel accumulation density rough.
Make some space. This is because the ignition burner is inserted from outside the furnace. (See FIG. 5) First, the suction blower 17 is put into operation and the burner is ignited from below the grate 11.

Due to the ignition and combustion of the fuel on the upper surface of the grate 11, not only the combusted fuel but also the fuel in the vicinity receives radiant heating, and volatile matter is decomposed and generated. A portion of these decomposed gases mix with the surrounding air and move upward toward the ceiling 3 while decomposing and burning.

As shown in FIG. Inflow.

The gas that has reached the lower part of the grate 11 is heated during combustion on the upper surface of the grate 11 (primary combustion), and also creeps into the upper surface of the grate 10 through the ventilation holes 9 around the four sides of the side wall 7 and flows into the gas. It is mixed with the air that has been expanded and combusted.

C It is decombustion.

That is, the decomposed gas that has circulated from the upper part of the combustion chamber 2 through the side wall 7 is combined with the newly supplied air under the grate 11, heated and combusted.

This decomposition combustion also generates radiant heat to activate and accelerate the grate 11.

The combustion gas generated by this decomposition combustion and the complete combustion gas that has circulated to the upper part are sucked into the gas suction port 15 from below the fire bed 10 and guided to the heat radiation pipe 16. This suction is performed by the suction blower 17 in operation.

In the heat radiation pipe 16, the combustion gas radiates heat, is used for heating warm air, hot water, etc., and is discharged to the outside through the suction blower 17.

In addition, in this combustion device, combustion is weak during the short period at the start of operation, and the ambient temperature is still low, so even if it mixes with the newly introduced air under the grate 11, complete combustion will not occur. However, even though the combustion is incomplete, the heat generated by the combustion of the gas gradually forms a high-temperature region, and as a result, the combustion becomes active all at once, and the synergistic effects begin to cause complete combustion of the gas.

Furthermore, this gas combustion (referred to as secondary combustion)
By heating the combustion area of 1 and the fuel, and conversely being heated by these, combustion (decomposition gas production) becomes more active, and the secondary combustion under the grate 11 is completed, resulting in complete combustion gas. be discharged.

Of course, increasing the temperature of the In cylinder and the combustion chamber as a whole also promotes complete combustion.

By the way, as a result of experiments conducted on the combustion apparatus manufactured by the present invention, the combustion apparatus according to the present invention was found to show that after ignition and combustion, black smoke was emitted at the beginning, white smoke was emitted after about 30 minutes, and after about 40 minutes, there was no smoke at all. reached. Further, when the temperature under the grate 11 was measured after the smokeless condition, it was approximately 1000°C.

As mentioned above, when the decomposition combustion is almost completed, the inside of the combustion chamber 2 is
In other words, the remaining wood is being burnt, complete combustion continues, and this complete combustion gas number, gas suction port 15,
It is sucked into the transmission pipe 16.

<Effects of the Invention> As described above, the present invention is capable of generating and producing gas by "upward combustion" on the grate 11 (flowing air from below the grate 11 to move the combustion to the first chamber). The cracked gas is circulated to the lower part of the combustion chamber, flows under the grate 11, heats this high-temperature region during circulation, and mixes with fresh air, so complete combustion is achieved.

Particularly, this is because it is mixed with sufficient air in the high temperature range. Unlike conventional combustion equipment, oxygen starvation does not occur.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, and FIG. 1 is a longitudinal sectional view;
FIG. 2 is a partially cutaway horizontal sectional view, FIG. 3 is a sectional view during operation, and FIG. 4 is a sectional view of a conventional combustion device.

Claims (1)

[Claims] A combustion chamber surrounded by a ceiling at the top, a grate at the bottom, and side walls on all four sides, a ventilation hole arranged around the side wall at a position close to the grate, and a combustion chamber. A grate installed at the required height above the grate surface in the center, a gas suction port provided on the grate surface below the grate, and a suction blower connected to this gas suction port via a heat transfer tube, etc. During combustion, the decomposed gas generated and rising on the above-mentioned grate is circulated from the above-mentioned ceiling to the lower part of the grate along the inner surface of the side wall. It mixes with the air that flows in along the surface and burns.
A solid combustion device that distributes combustion gas from the suction port to the heat transfer tube and suction blower.