JPS59176502A - Woody pellet-shaped fuel combustion device - Google Patents

Abstract

PURPOSE:To provide a combustion device which eliminates the need for a clinker removing work or addition of a removing device even if high-efficient high- temperature combustion is continued for a long time and performs complete combustion in that even any flying sparks are not mixed in exhaust gas, by a method wherein swirling movement, attended with the cyclone effect of a centrifugal force, is applied on fuel pellet, and solid content is circulated in a furnace body. CONSTITUTION:When ignition is effected by the use of auxiliary fuel, blowers 11 and 12 are started, and regulating valves 13, 14 and 16 are opened, pellet fuel is dropped from a fuel tank 15 to a bottom plate 2 through a secondary air inlet 5. The pellet fuel is rolled by the air through a primary air inlet 3 and is raised as it is swirled, as shown by an arrow mark, along the inner periphery of a drum body 1 by a centrifugal force, and continues to burn in a condition to produce smoke of unburnt gas. Thereafter, swirling movement of combustion pellet and unburnt gas is further prmoted with the aid of the air from the secondary air inlet 5, and combustion is promoted to complete combustion thanks to a swirling flow. Further, the separated solid content is circulated and flows to the bottom plate 2 again through an unburnt fuel introducing port 8.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a combustion device for generating a heat source by burning wood pellet fuel.

Conventional wood pellet fuel combustion devices, like other general combustion devices, used a grate or something similar, and the principle was to blow air from below the fuel to cause combustion.

However, when wood-based fuels are burned at low temperatures, they leave a white fine powder called ash after combustion, which generally results in low-efficiency combustion. In order to make this highly efficient, it is 800″O~1
When burned at a high temperature of 000'a or more, the ash content melts and adheres, leaving a porous glassy solid content called clinker. Over time, this clinker fuses to the inside of the combustion device, the grate, etc., obstructs air circulation, lowers combustion efficiency, and eventually makes combustion impossible. Therefore, it was necessary to maintain low-temperature combustion with low efficiency, or to install or remove clinker. Another disadvantage of conventional wood-based pellet fuel combustion devices is that large solid particles, so-called sparks, are mixed in the exhaust gas coming out of the chimney and adhere to external objects, causing many problems.

Therefore, the object of this invention is to provide a combustion device that does not require clinker removal work or the addition of a removal device even if high-efficiency, high-temperature combustion is maintained for a long period of time, and that performs complete combustion with no sparks mixed in the exhaust gas. This is what I did. To explain the outline, the furnace body is formed into a cylindrical or conical shape,
A bottom plate with an inclination approximately equivalent to the slip angle of wood pellet fuel is installed on the bottom, and a primary air inlet is installed at the bottom of the bottom plate.
In addition, a secondary air inlet that also serves as a fuel supply port is installed in the middle in the tangential direction of the fuselage, and an unburned fuel outlet is provided in the tangential direction in the upper part of the fuselage. A top plate is attached to the top of the furnace body, an exhaust pipe is installed in the center of the top plate, and the entire outer periphery of the furnace body is covered with heat insulating material. It is made up of With this structure, the wood pellets and torpedo fuel that are first ignited with auxiliary fuel such as kerosene are combusted while being swirled by the primary air from the bottom of the bottom plate, and then combusted while being swirled by the secondary air from the middle part. Some of the unburned fuel continues to burn as it becomes finer and falls to the bottom, while some of it is sent from the unburned fuel outlet at the top through the guide passage and into the furnace again from the inlet to continue burning. It is gradually pulverized and completely combusted in the furnace, leaving no solids in the furnace body and producing no sparks outside the furnace.This allows a heat exchanger to be connected to the exhaust pipe to release hot water or The present invention provides a highly efficient wood pellet fuel combustion device that generates hot air and can be used as a heat source for home heating or industrial greenhouses.

An embodiment of the present invention will be described below with reference to the drawings.The furnace body (1) is formed into a cylindrical or conical shape.The bottom surface of the furnace body (1) has a bottom plate with an inclination approximately corresponding to the sliding angle of the wood pellet-shaped fuel. (2) is used for military service, and a primary air inlet (3) is attached to the lowest part of the tank in the tangential direction of the fuselage (1), and wood pellets are also installed near the center of the fuselage (1) in the tangential direction of the fuselage (1). Secondary air inlet (5) that also serves as fuel supply port (4)
Furthermore, an unburned fuel outlet (6) is provided in the tangential direction of the fuselage (1) near the upper part of the fuselage, and from this, the unburned fuel is passed through the guide passage (7) to circulate through the fuselage near the lower part of the fuselage. (1) Unburned fuel inlet (
8), a top plate (9) is attached to the upper surface of the furnace body, an exhaust pipe θ1 is provided in the center of this, and the entire outer periphery of the furnace body (■) is covered with a heat insulating material (L). It is something. In the drawings, 0υ and (2) are blowers, θ and 04 are blower control valves, 0→ is a fuel supply tank, OQ is a fuel supply control valve, and Q71 is a dust collection port. Further, the present invention may have a structure in which the furnace body is installed at an angle.

In the present invention configured as described above, pellet fuel is initially ignited with auxiliary fuel such as kerosene, starts blowers 0◇ and 0, and opens each control valve a'+, rs, and 0. From 0 o'clock in the tank, it passes through the secondary air inlet (5) and falls onto the bottom plate (2), and is rolled by the air from the secondary air inlet (3), and the inner periphery of the body (1) is struck by centrifugal force. As shown by the arrow, it rises while turning and continues to burn while producing smoke of unburned gas. Next, the secondary air from the secondary air inlet (5) further promotes the swirling movement of the combustion pellets and unburned gas, and the swirling flow promotes combustion to complete combustion.

The swirling movement of the combustion pellets, gas and combustion gas caused by the primary and secondary air described above separates the combustion gas and ultrafine particles, which have little centrifugal force effect, into the central part in the upper part of the furnace body, while the unburned Ash (hereinafter referred to as solid content) containing pellets, ash, and clinker is separated on the inner periphery of the body (1) by the centrifugal force effect. Some of the solids separated on the inner peripheral surface of the body (1) fall directly while swirling, and the rest flows into the unburned fuel outlet (6) and into the guide passage (
7), the unburned fuel inlet (8), and the bottom plate (2) again.
) is circulated upward, mixed with new fuel pellets, further atomized, and converted into combustion gas for complete combustion. As a result of the circulation of these solids, the solids are successively pulverized within the furnace body due to the swirling movement caused by centrifugal force, and the solids that have been pulverized to the extent that they cannot be separated are sent to the outside from the exhaust pipe (10) in the upper center along with the combustion gas due to the centrifugal effect. leak.

The fine particles in the outflow gas are suspended in the outflow gas and air and do not have any adverse thermal effect on objects outside the furnace.

Furthermore, at the end of combustion, if only the primary and secondary air is continued to be blown after closing the fuel supply control valve α, the fuel pellets in the furnace body ① will be pulverized and completely combusted while repeating the above-mentioned circular combustion. No solid matter flows out from the exhaust pipe (10) and remains in the furnace body.

However, during the circulation, the dust collection port at the bottom of the guide passage (7)
It is also possible to remove the accumulated dust by opening the blind plug in 7).

As explained above, the present invention generates a swirling motion of fuel pellets accompanied by the cyclone effect of the centrifugal force caused by the primary and secondary air supply provided in the tangential direction of the fuselage of the furnace body.

In addition to increasing the efficiency of the combustion effect, solid matter is circulated within the furnace body in the process to make it atomized, eliminating the generation of so-called sparks outside the furnace body, and eliminating the generation of so-called sparks outside the furnace body. This is a high-efficiency wood pellet fuel combustion device that is effective in keeping unburned solids from remaining.

In addition, in the present invention, the high-temperature combustion gas rotates inside the furnace body, and the inner circumferential surface of the body is covered with solid matter due to the centrifugal force effect, which has the effect of preventing corrosion caused by the high-temperature gas in the furnace body. An effective invention for generating hot water or hot air by connecting various heat exchangers to this exhaust pipe, and generating a highly efficient heat source that can be used for various domestic or industrial heating systems, greenhouses, etc. It is.

[Brief explanation of drawings]

The drawings show one embodiment of the present invention, with FIG. 1 being a plan view and FIG.
3 is a sectional view taken along the line X--X of FIG. 1, and FIG. 4 is a perspective view of a partially cutaway cross-section of the whole. 1...Body 2...Bottom plate 3...-Next air inlet 4...
Fuel supply port 5. Secondary air inlet 6. Unburned fuel outlet 7. Guide passage 8. Unburned fuel inlet
9...Top plate 1o...Exhaust pipe 11.12...Blower 1
3.14...Air blow control valve 15...Fuel supply tank 1
6.Fuel supply control valve 17.Dust collection port ■.Furnace body patent Applicant: Japan Steel Works, Ltd. (2 others)

Claims (1)

[Claims] At the bottom of the furnace body, which has a cylindrical or conical body, a bottom plate with an inclination approximately equivalent to the sliding angle of the wood pellet-shaped fuel is installed, and at the bottom of the bottom plate, a primary air inlet is oriented tangentially to the body. In addition, install one or more secondary air inlets that also serve as wood pellet fuel supply ports near the center of the fuselage in the tangential direction of the fuselage, and install an unburned fuel outlet near the top of the fuselage in the tangential direction of the fuselage. The unburned fuel is connected to the unburned fuel inlet tangentially to the fuselage near the lower part of the fuselage through a guide passage through which the unburned fuel circulates.A top plate is attached to the top of the furnace body, and an exhaust pipe is installed in the center of this. A wood pellet-shaped fuel combustion device is provided with a furnace body, and the entire outer periphery of the furnace body is covered with a heat insulating material.