JPH0231292B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a combustion device that easily and efficiently burns a low-ash solid fuel.

(Prior art) In recent years, various types of fuel have been used for various purposes such as heating, bathing, and boiling water, such as coal, other solid fuels, oil, and natural gas. Lignite, petroleum coke, calciner coke, coal pitch coke, etc. are known as solid fuels with low ash, and are inexpensive and high in calories.Currently, however, the use of petroleum, which is easy to ignite and has a low flash point, is significant, but in the future The supply amount and import costs are not necessarily stable, and storage is dangerous and management costs are incurred. Therefore, low-calorie and inexpensive solid fuels such as briquettes and coal are used, which are easy and safe to handle during transportation and storage, quickly ignite, and have no risk of fire or explosion.

One type of device for burning coal or other solid fuel is to horizontally install a rostol having a plurality of ventilation slits in the combustion chamber, deposit the solid fuel at a predetermined height on the rostrum, and ignite it as appropriate. After that, the solid fuel is ignited by a means of ignition, and then the solid fuel is continuously combusted. (Jikko No. 39-36175, No. 40-
(See No. 23003). However, due to the purpose of its use, the solid fuel requires heat retention and good fire life, and if the ash content is less than 10%, the ash will fall off the shelf and fall from between the roasters. However, even when burned, the ash retains its shape without falling off the shelf, and has a heat-insulating effect.Therefore, there is a large amount of ash left after combustion, which requires time and effort to dispose of. The cost was also relatively high due to the necessity of selecting raw materials and molding.

On the other hand, there were combustion devices in the form of sealed boxes without a lostle that burned cheaper solid fuels such as firewood and old wood. (a, Utility Model No. 56-124714, b, same
55-131433).

1. Utility Model Registration No. 363501, 2. Utility Model Registration No. 363501, 2. Utility Model Application No. 363501, Utility Model Registration No. 363501, 2.
1 of No. 19766 discloses that a wire (nichrome wire) is provided between each electrode 2-3, 2-4, and electricity is passed between the electrodes by this wire to ignite and ignite the charcoal powder. , the combustion device has a large-scale and complex configuration in which forced air is drawn by a fan into the solid fuel in the burner device through a duct, and the ignition device also has one high-voltage electrode that constitutes a spark plug that is grounded to the solid fuel. This is a large-scale, high-performance ignition device in which the electrode is connected to an ignition step-up transformer, and the other high-voltage electrode hangs down close to the igniter above the solid fuel at a certain interval.

(Problems to be Solved by the Invention) The conventional low-ash solid fuel has other advantages such as low cost, but it has a high sulfur content and has a negative effect on metals when burned, so care must be taken when using it as an industrial fuel. It was used in combination with coal and in kilns for firing cement where sulfur content was not a problem. Additionally, as a fuel for general heating, it has a unique odor due to its nature, and because of its low ash content, it is prone to shelving, contrary to solid fuels with an ash content of 10% or more. The fuel falls from the rostre as it burns, and the high-temperature combustion causes cracks in the fuel, increasing its surface area, further increasing the combustion rate, and the finer combustion fuel falls from the slits in the rostre, causing its temperature to drop due to heat dissipation. The combustion stops and becomes unburned residue, which is wasted. Therefore, not only does the efficiency of fuel use decrease, but also the amount of solid fuel deposited during combustion decreases, leading to an unexpected situation where the solid fuel disappears, or the fine fuel that falls from the slit of the roaster during combustion is removed. There are disadvantages such as being forced to do extra work that is necessary. In addition, low-ash solid fuels such as coke are sprayed with water during the manufacturing process, so if drying and dehydration are insufficient, the moisture contained in the coke will become steam due to the heat of the fire and cannot be fully released. It had the disadvantage of flying and falling even further from Lostol.

Among the combustion devices mentioned above, even though the fuel used in the closed box type type A without a roistle is high in ash, it has an ash reservoir below the base cylinder with a cap for intake, so that the ash after combustion is removed. In addition to the base cylinder, an air supply pipe with a damper and a chimney extending downward from the top of the base cylinder are installed for intake and exhaust for combustion, and when combustion becomes active, the base cylinder is closed and the air supply is removed. This is a configuration that requires complicated and time-consuming operation of the trachea. Moreover, an efficient natural intake/exhaust structure is not disclosed in the closed box type combustion apparatus described in b. Furthermore, the ignition means 1 and 2 are ignition means such as charcoal powder or briquettes, and in particular, the ignition means 2 has a large scale, high pressure, and complicated structure, and is a simple method for low ash solid fuel that is high in calories and difficult to ignite. The method of ignition is not disclosed.

Therefore, the present invention further enhances the utilization efficiency of the low ash solid fuel to facilitate ignition, improve combustion efficiency with natural aspiration, prevent undesired burnout, and reduce the amount of unburned residue left behind. The purpose is to

(Means for Solving the Problems) In order to achieve the above object, the present invention supports a low ash solid fuel on a flat receiving plate that does not have any ventilation slits or grooves. A bottomless cylindrical body is provided which is supported on a plate and surrounds the solid fuel to form a combustion chamber, and between the lower end of the cylindrical body and the receiving plate there is an intake air that is naturally drawn in proportion to the exhaust air.
A chimney with a lid and a damper that can be opened and closed on the cylindrical body, and an arc generating means that is energized to emit an arc when operated from the outside are provided on the receiving plate near the end of the combustion chamber. It is.

(Function) Low ash solid fuel is deposited in the combustion chamber on the receiving plate, and the fuel is ignited by a high-temperature arc generated by electricity, and the fuel is ignited by the intake air between the receiving plate and the lower end of the cylindrical body. When it burns, the combustion temperature gradually rises to a high temperature, and combustion continues with the natural intake of air from the intake air gap and the chimney.

(Example) An example of the present invention will be described in detail with reference to FIGS. 1 to 3. 1 is a low ash solid fuel with an ash content of approximately 5%
Lignite, ogalite or ash content below 1%
petroleum coke of less than 1,000 yen, and coal pitch coke, molded coke, briquette, calciner coke, etc. of the same extent as these. 2 is a receiving plate; 3 is a combustion cylinder whose inside constitutes a combustion chamber 4; it is supported on the receiving plate with an intake space 20 formed between it and the receiving plate via a plurality of legs 19 at the lower end; The low ash solid fuel is surrounded on a receiving plate. Reference numeral 5 denotes a body, which together with the combustion tube 3 constitutes a cylindrical body. Reference numeral 7 regulates the exhaust amount by a chimney damper 7'. 8
9 is a lid that can be opened and closed for charging fuel; 9 is a hole that supplies atmospheric air directly to the body 5 to adjust combustion; 10
is a ring that closes the hole 9.

The receiving plate 2 is mainly composed of a flat metal plate with a predetermined thickness, and a heat-insulating layer 21 is formed by pasting a heat-insulating material such as castable or heat-insulating bricks on the upper surface of the plate to a predetermined thickness. A shutter 15 for dropping the fuel or unburned residue is provided so as to be rotatable downward. 22 indicates a support leg.

The combustion tube 3 is mainly composed of a metal cylinder with a predetermined thickness, and a strong fireproof material with high heat insulation and heat retention ability is attached to the inner surface of the cylinder to form a heat insulation layer 18. is formed into a downwardly tapered surface. Therefore, the heat insulation layer 18
Due to this structure, the lower end of the combustion cylinder has a donut-shaped end surface, and its center hole is located between 20 mm and the intake plate with the lower receiving plate.
It opens to serve as a communication port with the inside of the combustion chamber 4.
Note that the heat insulating layer 18 may be formed on a vertical wall surface. The combustion tube 3 has a circular cross section, as well as 8, 6, 5,
4. It is configured in various shapes such as triangular and other shapes depending on the necessity and design requirements depending on the installation location.
In the figure, reference numeral 13 indicates a pin, and reference numeral 14 indicates a gap adjustment cylinder.

FIG. 1 shows a carbon rod 16 that is the ignition means 12, a metal plate 17 that comes into contact with and separates from the carbon rod, and a receiving plate 2.
As shown in the figure, a carbon rod 16 and a metal plate 17, which are durable against high heat, are set on the upper surface of the receiving plate 2, and the operation unit 1 swings the metal plate toward and away from the carbon rod.
By locating 7' outside the combustion chamber 4,
It is easy to operate and prevents damage caused by the high temperature atmosphere during combustion.

In addition, the reason why the metal plate and carbon rods are provided near the periphery of the receiving plate is to prevent the rocking of the metal plate from being obstructed by the presence of low-ash solid fuel to be introduced into the combustion chamber. If it is possible to ensure the reciprocating movement of the plate relative to the carbon rod, it is convenient to provide the arc generating means in the center of the receiving plate where a large amount of low ash solid fuel is present, since this will increase the ignition efficiency.

The operation of the low ash solid fuel combustion device with the above configuration is as follows.

Combustion chamber 4 on the receiving plate as shown by the chain line in Figure 1
A low ash solid fuel 1 is accumulated in the interior, and a DC voltage is applied between the carbon rod 16 and the metal plate 17.
When the metal plate 17 is swung manually or by power, an arc is generated between the metal plate and the carbon rod. The fuel is heated by the high-temperature arc and its temperature rises, and volatile matter comes out of the solid through thermal decomposition and burns in the air inside the combustion chamber, and the atmospheric temperature of the combustion chamber rises until the temperature reaches a predetermined temperature. After that, the fuel obtains oxygen from the intake air, reaches the ignition point, and begins to burn. When the fuel starts to burn and all the solids deposited become red hot and radiant heat burns at a high temperature, the solid fuel cracks and becomes fine and blown away. Since it is supported between the peripheral surfaces of the combustion chamber, even fine fuel does not fall outside the receiving plate and stays in the high temperature area surrounded by the receiving plate and the combustion chamber 4, and the radiant heat and heat retention effect are achieved by the heat insulating layer of the combustion chamber. The combustion continues due to the intake effect from the surrounding outside air. As a result of the combustion, the combustion exhaust gas is discharged through the chimney 7, and the atmosphere is drawn into the combustion chamber 4 through the intake space 20 as an upward air current between the accumulated fuels.

It has been confirmed through experiments that the dimension of the intake space 20 has a large effect on the combustion of the fuel, and by setting an appropriate balance between the intake and exhaust, low ash solid fuel can be produced even if it is not stacked thickly. The fuel can be pumped vigorously, and there is no need to install any special blower device. That is, the intake interval is 20
If the temperature is too high, a large amount of cold air will flow into the combustion chamber, and the rate of heat dissipation will exceed the rate of heat generation, lowering the atmospheric temperature of the combustion chamber, which may cause the fuel to disappear.
If the dimensions of the combustion chamber are made too small, the amount of air flowing into the combustion chamber will be too small, and there is a risk that the fuel will run out or a backup fire will occur.

As the combustion continues, the amount of the low ash solid fuel 1 gradually decreases, and when it approaches the limit amount that allows continued combustion, the combustion can be further continued by opening the fuel inlet 6 and adding additional fuel. . Additional input may be done either manually or mechanically. Therefore, a temperature sensing element is provided to detect the temperature of the combustion exhaust gas passing through the chimney 7, and when the temperature of the combustion exhaust gas detected by the temperature sensing element falls below a predetermined temperature, a predetermined amount of low ash solid fuel 1 is provided. By providing a supply device for supplying fuel, it is possible to reliably prevent combustion from being interrupted due to forgetting to supply fuel.
When the combustion is to be interrupted, a so-called extinguisher pot made of an insulating material and airtight is provided, the shutter 15 is opened, the fuel in the combustion chamber is poured in, the shutter is covered, and the extinguisher pot is taken out. Alternatively, the gap adjustment tube 3b may be lowered to close the intake gap 20 and open the holes 9, 9, . . . . Furthermore, when petroleum coke with an ash content of 0.2% is used as a low-ash solid fuel, the amount of unburned petroleum coke on the receiving plate after combustion is approximately 10 g compared to the initial input amount of 500 g.
This residual fuel can be re-combusted. Even if 500 g of petroleum coke is added several times and burned continuously, the amount of petroleum coke remaining unburned on the receiving plate is about 10 g, which hardly changes. Moreover, in this case, almost no ash was observed.

(Effects of the Invention) The present invention has the above-described structure and operation, and when a low ash solid fuel that causes cracks during combustion is supported on a receiving plate that does not have slits, surrounding the fuel in a combustion chamber;
Since the structure is configured so that the intake air from the intake gap formed between the lower end of the cylindrical combustion chamber and the receiving plate is proportional to the exhaust air from the chimney, the fuel is naturally drawn in even though the overall structure is extremely simple. Since the fuel can be naturally and continuously combusted, the fuel can be almost completely combusted without any loss, and therefore almost no ash is produced. In addition, if a small amount of ash or unburned material remains after continuous combustion, the intake air on the receiving plate
It is convenient to scrape out the ash from between the ash or remove the cylindrical body from the support of the receiving plate and tilt the receiving plate to allow the ash to fall immediately and be removed. Therefore, there is no inconvenience such as in a conventional closed box type combustion device where the ash accumulates in the bottom of the combustion device and there is no outlet for taking out the ash, and the lid must be removed one by one and the entire device must be tilted.
Low ash solid fuels, which are made into fine particles like various types of coke and required time and effort to be remolded and processed into fuels that prevent blowouts, can now be burned efficiently in their unprocessed state. Furthermore, almost complete combustion of the fuel prevents the generation of harmful gases and pollution due to ash, and has the unique effect of allowing low-cost solid fuel to be used as is. By providing a shutter on the receiving plate, you can easily remove ash and unburned residue.
can be easily eliminated. The arc generating device, which is the ignition means, is easy to configure and operate, and is heat-resistant and low-volume and is integrally attached to the receiving plate inside the combustion chamber, and can ignite high-calorie fuel simply and reliably by red-hot to a high temperature.
Moreover, there is no risk of it going out before it ignites.
Unlike conventional fire starters, it does not turn into ash itself.

[Brief explanation of drawings]

The drawings show an embodiment of the low ash solid fuel combustion device of the present invention, FIG. 1 is a simplified plan view showing the ignition means, and FIG. 2 is a simplified vertical cross-section of the main part showing the usage state of the ignition device. FIG. 3 is a vertical cross-sectional view of the above combustion device in use. 1...Low ash solid fuel, 2...Receiving plate, 3...
Combustion tube, 3a... Gap adjustment tube, 4... Combustion chamber, 5
... body, 7 ... chimney, 7' ... damper, 8 ...
Lid, 20...Intake space, 12...Ignition means.

Claims (1)

[Claims] 1. A receiving plate made of a durable, heat-resistant material such as metal of a specified thickness and having no slots, slits, etc. for supporting low ash solid fuel, and a supporting plate of the same effective quality supported on the receiving plate to support the combustion chamber. A heat insulating layer of a predetermined thickness made of heat insulating bricks or other heat insulating material is provided around the receiving plate and the combustion chamber to support and surround the low ash solid fuel, An intake gap is formed between the lower end of the combustion cylinder and the receiving plate to allow continuous supply of combustion air in proportion to the exhaust air, and an openable and closable shutter for removing ash is provided in the center of the receiving plate, and a peripheral edge on the receiving plate is provided. A carbon rod and a metal plate that swings into and out of contact with the carbon rod are provided in the leaning part, an operating part for swinging the metal plate and an arc generating means are provided outside the combustion chamber, and the cylindrical body has a metal plate that swings into and out of contact with the carbon rod. A low ash solid fuel combustion device equipped with a chimney equipped with an openable and closable fuel inlet and a damper.