JP2012247143A - Natural air-intake combustion equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide natural air-intake combustion equipment for burning wood fuel such as wood by powerful natural air-intake by a simple structure and recovering exhaust heat at high efficiency and at a low fuel cost, although a general method for achieving complete combustion in a wood-burning stove burns a large amount of wood, to cause secondary combustion to take place using a complicated device, or to supply a large amount of air using a fan.SOLUTION: In the natural air-intake combustion equipment, wood fuel such as wood is burnt in a primary combustion chamber and flame, heat, unburned gas, and smoke generated in the primary combustion chamber is sucked powerfully into a combustion connection path communicating with the primary combustion chamber and a secondary combustion chamber and complete combustion in a spiral form takes place at the bottom of the secondary combustion chamber. Furthermore, it is made possible to make the fine adjustment of thermal power by a combustion air opening/closing port for adjusting sucked air for combustion provided at both ends of the primary combustion chamber and a cylindrical thermal power adjusting valve attached closely to the wall in the secondary combustion chamber. Furthermore, heat is taken into a discharge heat recovery chamber and exhaust at a low temperature is discharged to the outside of the chamber.

Description

The present invention relates to an apparatus for efficiently burning woody fuel such as firewood by natural intake and recovering heat.

When burning woody fuel such as firewood, if the combustion temperature and air volume are insufficient, a large amount of smoke is generated. There is a combustion apparatus in which a large amount of fuel is introduced to sufficiently raise the temperature of the combustion chamber and secondary combustion is performed before exhaust. In Patent Document 1, secondary combustion is performed by a combustion promoting plate and a dry soot inlet.

As a device for reducing exhaust smoke, there is a stove that promotes secondary combustion using a catalyst such as platinum. Patent Document 2

There is a wood-burning stove that considers a long vertical and closed-type wood-fired supply section that enables improved combustion using the structure of the “rocket stove”. Patent Document 3

The rocket stove insulates the combustion chamber body and realizes excellent combustion efficiency by the powerful intake of the secondary combustion chamber called heat riser. In addition, there is a device that enables a 12-meter horizontal chimney, which was difficult with a conventional wood stove, by virtue of its powerful intake and exhaust, and that effectively collects heat by storing the exhaust heat from the chimney in soil or brick. Non-patent document 1

2. Description of the Related Art There is a combustion apparatus that includes a combustion chamber that exchanges heat generated by burning solid fuel with a medium, and that has a sub-combustion chamber that is connected to a main combustion chamber via a connection path. Patent Document 4

JP 2009-250579 A (FIGS. 1 and 2) JP 2000-046334 A (FIG. 2) Jito 3165517 (Figure 3) JP 2008-122201 (FIGS. 1 and 5)

Rocket Stove ~ With Rocket Stove Japan Collection ~ Co-authored by Iant Evans + Leslie Jackson

Japan's greenhouse gas reduction is no longer an international commitment, and as is evident from a serious accident at a nuclear power plant, the use of renewable biomass energy is also required in ordinary households, and how efficiently it can be burned to generate heat without waste. It is necessary to recover the energy.

However, many conventional wood-based fuel combustion apparatuses combust at a high temperature for complete combustion and exhaust high-temperature exhaust gas due to the chimney effect. Patent Document 1

As a method of reducing smoke, a complicated secondary combustion system or a combustion apparatus using a catalyst is incurring high costs. Patent Document 2

The rocket stove is efficient, but it is large, heavy and difficult to install in ordinary houses. If soil or brick is used, it takes time to store heat, and it is necessary to throw in thin firewood frequently. Management is difficult. Non-patent document 1

In the long vertical and sealed type of firewood supply part of Patent Document 3, the heat and smoke accumulated at the top when the firewood is thrown out and at the same time there is a risk of burns and fire, and it is not suitable for houses. The hail does not necessarily fall naturally due to friction with the hail supply unit.

In Patent Document 4, a stable combustion cannot be expected without supplying a solid fuel such as pellets and combustion air without a device that requires an external power source.

The temperature of the primary combustion chamber by burning wood-based fuel such as soot from the center of the horizontal cylindrical or rectangular cylindrical primary combustion chamber to both ends of the primary combustion chamber where wood-based fuel such as soot to be burned can be input To raise.

The flame, heat, unburned gas, and smoke in the primary combustion chamber are strongly sucked into the combustion connection path without flowing back to the combustion air opening / closing port for adjusting the intake air of the combustion air.

The combustion connection path eccentrically connected from the center of the circular section of the cylindrical secondary combustion chamber makes it easy for the flame, heat, unburned gas, and smoke to form a spiral secondary combustion at the bottom of the secondary combustion chamber. Complete combustion.

The bottom of the secondary combustion chamber can be adjusted for inflow from the combustion connection path by a thermal power control valve closely attached to the wall of the cylindrical secondary combustion chamber and a combustion air opening / closing port for intake adjustment of combustion air, Fine thermal power adjustment is possible.

Exhaust gas completely burned at the bottom of the secondary combustion chamber rises to the top of the secondary combustion chamber, collides with the top plate in the exhaust heat recovery chamber, falls to the external chimney connection port, and is exhausted.

The primary combustion chamber in the cylindrical or rectangular tube shape is easy to ignite because the fire is fast, and wood-based fuel such as soot burns from near the center of the primary combustion chamber to both ends of the primary combustion chamber. Heat, unburned gas and smoke are also strongly drawn into the combustion connection. Furthermore, at the bottom of the cylindrical secondary combustion chamber, the flame, heat, unburned gas and smoke from the combustion connection path which is eccentrically connected from the center of the circular cross section of the secondary combustion chamber are strongly applied to the bottom of the secondary combustion chamber. Then, it is sucked into the vortex and secondary combustion is completed and complete combustion. In the vicinity of the bottom in the secondary combustion chamber, stable combustion exceeding 600 degrees can be performed, and the secondary combustion chamber can be heated to a high temperature in a short time.

The exhaust heat of the high-temperature exhaust gas exhausted to the upper portion of the secondary combustion chamber is taken into the chamber in the exhaust heat recovery chamber, and at the same time, the primary combustion chamber, the combustion connection path, and the secondary combustion chamber covered with the exhaust heat recovery chamber The interior of the primary combustion chamber, combustion connection path, and secondary combustion chamber is kept at a high temperature with a small amount of wood-based fuel such as soot from the fuel of the normal wood stove, enabling stable combustion. Become.

In addition, since it has a double structure, it is a combustion device with little risk of burns and fires.

In the case of wood-based fuel such as firewood, the thermal power adjustment is generally performed by adjusting the fuel amount and the combustion air. However, the present invention provides a combustion air opening and closing port for adjusting the combustion air and a thermal power adjustment valve in the secondary combustion chamber. Thus, it is possible to adjust the heating power of the fine spiral secondary combustion.

Due to the spiral secondary combustion, the exhaust gas of wood-based fuel such as firewood can be completely burned with a simple structure with strong natural aspiration, and it becomes a highly efficient and energy-saving combustion device that does not require a power source.

Plan view of a naturally aspirated combustion apparatus to which the present invention is applied Right side view of natural intake combustion system Combustion chamber perspective view Thermal control valve perspective view

Hereinafter, embodiments for carrying out the present invention will be described with reference to FIGS. 1 to 4.

A naturally aspirated combustion apparatus mainly composed of a primary combustion chamber 2, a combustion connection path 3, a secondary combustion chamber 4, a thermal power control valve 5, and an exhaust heat recovery chamber 10.

It has a horizontal cylindrical or square cylindrical primary combustion chamber 2 into which woody fuel such as soot to be burned can be put, and a fuel supply and ash takeout lid 7 at both ends of the primary combustion chamber 2 and a lower portion of the lid 7 The structure which provides the combustion air opening-and-closing port 9 for adjustment of combustion air.

Side plates are provided on the top plate and the bottom plate with a slight upward slope from the vicinity of the center of the primary combustion chamber 2 from the top and bottom of the primary combustion chamber 2 or horizontally to the secondary combustion chamber 4, and at the bottom of the secondary combustion chamber. A configuration of a rectangular tube-shaped combustion connection path 3 extending and connected eccentrically from the center of a circular cross section of a substantially vertical cylindrical secondary combustion chamber 4.

A gap is provided between the upper part of the cylindrical secondary combustion chamber 4 and the lower part of the top plate of the exhaust heat recovery chamber 10, and the side plate of the exhaust heat recovery chamber 10 sealed by the top plate, bottom plate, and side plate of the exhaust heat recovery chamber 10. The structure which provides the external chimney connection port 11 near the lower part or the bottom plate.

A configuration in which a thermal power adjustment valve 5 capable of opening and closing a combustion connection path 3 in close contact with a wall of the secondary combustion chamber is interlocked with a thermal power control valve handle 6 at the bottom of the cylindrical secondary combustion chamber 4.

When a new wood stove is newly installed in a house, the retrofitting chimney work is carried out on the ceiling or high wall and the construction cost is high. In addition, double insulated chimneys are standard in expensive wood-burning stoves that are considered to have good thermal efficiency.

According to the present invention, exhaust can be performed with a single chimney from the exhaust heat recovery chamber. From the experimental results, exhaust is performed even when the chimney is horizontally pulled by about 4 m. In this case, the surface temperature of the upper end of the exhaust side of the chimney in the room is 30 The temperature can be lowered and the exhaust can be exhausted from a low position close to the feet of the installation surface of the naturally aspirated combustion device, facilitating retrofitting work.

DESCRIPTION OF SYMBOLS 1 Natural intake combustion apparatus 2 Primary combustion chamber 3 Combustion connection path 4 Secondary combustion chamber 5 Thermal power control valve 6 Thermal power control valve handle 7 Fuel supply and ash take-off lid 8 Heat-resistant glass observation window 9 Combustion air opening 10 Exhaust heat recovery chamber 11 12 external chimney connection ports

Claims (5)

A lid for fuel supply and ash removal is provided at both ends of the primary combustion chamber of a horizontal cylindrical or rectangular tube that can be filled with woody fuel such as soot to be burned, and the intake air adjustment of combustion air is provided at the bottom of the lid A combustion air opening / closing port for the cylinder, connected to the square cylinder-shaped combustion connection path provided near the center of the primary combustion chamber, and connected to the square cylinder-shaped combustion connection path so as to stand substantially vertically and extend A cylindrical secondary combustion chamber, and burns wood-based fuel such as soot from near the center of the primary combustion chamber to both ends of the primary combustion chamber, and further through the rectangular cylinder-shaped combustion connection passage for primary combustion Flame, heat, unburned gas and smoke generated in the chamber are strongly sucked into the cylindrical secondary combustion chamber and are completely burned in a spiral shape at the bottom of the cylindrical secondary combustion chamber. A naturally aspirated combustion device characterized in that The top plate and bottom plate of the square cylindrical combustion connection channel are a cylindrical or square cylinder with a slight upward gradient from the top and bottom of the horizontal or secondary combustion chamber to the horizontal or secondary combustion chamber. 2. The naturally aspirated combustion apparatus according to claim 1, wherein the natural intake combustion apparatus is connected to a bottom portion of the next combustion chamber. One side plate of the rectangular tube-shaped combustion connection path is at the intersection of the cylindrical secondary combustion chamber with the vicinity of the center line of the circular cross section, and the other side plate is a cross section on the right or left side of the secondary combustion chamber. The naturally aspirated combustion according to claim 1 or 2, wherein the combustion connection path is connected near a tangent to a circle, and the combustion connection path is provided so as to be eccentric from a center of a circular section of the secondary combustion chamber. apparatus. Thermal power adjustment in close contact with the wall of the secondary combustion chamber that moves circularly in the direction of closing the combustion connection path from the center direction of the circular section of the secondary combustion chamber to the right or left side at the bottom of the cylindrical secondary combustion chamber A thermal power adjustment valve handle that enables fine thermal power adjustment by the thermal power adjustment valve and the combustion air opening and closing port for intake adjustment of the combustion air, and further allows the thermal power adjustment valve to be operated at a position away from the main body. The naturally aspirated combustion apparatus according to claim 1, wherein the natural intake combustion apparatus is provided. An exhaust heat recovery chamber is provided in which the primary combustion chamber, the combustion connection path, and the entire secondary combustion chamber are hermetically covered with a steel plate. The primary combustion chamber, the combustion connection path, and the secondary combustion chamber are kept warm by their own exhaust heat, and the primary combustion chamber The inside of the combustion chamber, the combustion connection path and the secondary combustion chamber are kept at a high temperature to allow stable combustion, and exhausted from the vicinity of the lower part of the side plate of the exhaust heat recovery chamber or from the external chimney connection port provided on the bottom plate. The naturally aspirated combustion apparatus according to claim 1, claim 2, claim 3, or claim 4.