JPS6319761B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention provides a method for using fuel such as pulverized coal,
The present invention relates to a combustion device suitable for fuel containing a large amount of ash at 30% to 50%.

[Prior Art] Regarding such a combustion device, Japanese Patent Publication No. 10147/1987 discloses a double cyclone combustion device consisting of a front cyclone and a rear cyclone. However, this device is not suitable for the high melting point of the ash content, which is about 1300°C.
In addition, in Japanese Patent Publication No. 32-3908, a secondary cyclone is provided in communication with the upper part of the primary cyclone, and a baffle plate provided in the communication part changes the direction of the rising combustion gas in the radial direction to control the temperature. A part of the molten flyash contained in the gas as a mist is attached to and separated from the baffle plate, and the remaining part is returned to the primary cyclone from between the secondary cyclone peripheral walls.
A cyclone furnace is shown that melts and extracts it to the outside. However, in this device, the primary ash separation efficiency of the primary cyclone is low.

[Object of the Invention] Therefore, an object of the present invention is to provide a combustion device with high ash separation efficiency.

[Structure of the Invention] According to the present invention, a first stage combustion chamber of a cyclone combustion chamber is provided, and the cyclone combustion chamber is provided with a fuel supply means, a combustion aid supply means, and an inner swirling flow from above and along the peripheral wall surface. A primary air supply means consisting of an outer swirl flow and a constricted portion at the bottom are provided, a vertical flame path is provided below the constricted portion, and a horizontal flame path is provided on the side of the vertical flame path. A baffle plate is provided in the flame path of the flame duct, a water tank equipped with means for removing lump ash is provided below the baffle plate, a second stage combustion chamber is provided at the front of the horizontal flame duct, and a second stage combustion chamber is provided in the combustion chamber. Next, air supply means are provided.

[Operations and Effects of the Invention] Therefore, the fuel (i.e., pulverized coal) and the combustion aid are sandwiched between both swirling air flows and are supplied to generate a high-temperature hollow flame in the cyclone combustion chamber, and the baffle plate absorbs the ash of the pulverized coal. at a high enough temperature to melt (e.g.
The baffle plate captures the molten ash well and allows it to flow down into the water tank, and discharges it from the extraction means to separate the ash contained in the pulverized coal with high separation efficiency (e.g. 95%). Can be separated.

[Preferred Embodiment] When carrying out the present invention, it is preferable to provide a baffle plate and a water tank also in the lateral flame duct. In this way, the ash separation efficiency can be further improved (for example, to 98%).

[Examples] Examples of the present invention will be described below with reference to the drawings.

In FIG. 1, 1 is a first stage combustion chamber, that is, a cyclone combustion chamber having a cylindrical inner circumferential wall. A pulverized coal supply means 2 and an auxiliary fuel supply means 3 are provided above the cyclone combustion chamber 1. In addition, the primary air supply means 4 is designed to supply approximately 0.8 of the theoretical amount of oxygen necessary for combustion of the fuel supplied into the cyclone combustion chamber 1.
Provided for. The primary air supply means 4 consists of an inner swirling flow that is supplied from above while being swirled, and an outer swirling flow that is supplied from a jet hole provided in a cylindrical inner circumferential wall surface along the circumferential wall surface. .

A slightly constricted part 5 is provided at the lower part of the cyclone combustion chamber 1, and a vertical flame path 16 is provided below the constricted part 5. There is a horizontal flame path 1 on the side of the vertical flame path 16.
0, and a second stage combustion chamber 1 is provided ahead of the horizontal flame path 10.
1 will be provided.

Combustion air is heated by the air preheater 14, which is the outer chamber of the second stage combustion chamber 11, by the blower 13, and about 80% of the theoretical oxygen amount is used as primary air in the cyclone combustion chamber 1. The air is divided into an inner swirl flow and an outer swirl flow, and approximately 30% of the air is supplied as secondary air to the second stage combustion chamber by the supply means 12.

Also, below the slightly squeezed part 5, the vertical flame path 16
A convex member 15 having a slightly larger cross-sectional area than the constricted portion 5 is fixedly provided. A water tank 6 is provided directly below the convex member 15, and water is supplied to the water tank 6. Water supply means 7 and the water tank 6
Removal means 8, 9 are provided for removing the coagulated lump ash therein.

Therefore, the pulverized coal and the auxiliary combustion material are supplied sandwiched between the two swirling flows, and a high-temperature hollow flame is generated in the cyclone combustion chamber 1. The convex member 15 makes it easy to create a hollow flame at a high temperature of, for example, about 1500°C, which is high enough to melt the ash of the pulverized coal in the cyclone combustion chamber 1, and the ash of the pulverized coal is used to melt the ash of the pulverized coal into the cyclone combustion chamber 1. The convex member 15 flows down or descends from the constricted portion 5 along the cylindrical peripheral wall.
The surface of the convex member traps ash like flypaper, and the trapped ash flows down along the surface of the convex member and drops from the periphery to the water tank 6 below, and then from the water tank 6. It can be extracted as agglomerated ash. As a result of experiments, it was found that this convex member 15 could capture 95% of the ash contained in the pulverized coal.

FIGS. 2 to 4 show another embodiment of the present invention, further including a V-shaped vertical member 21 in the lateral flame duct 10,
21'... This is an example in which a large number are provided. That is, vertical members 21, 21' with a V-shaped cross section are provided in the horizontal flame path 10.
A large number of them are fixedly arranged in several rows with the front and rear rows arranged in a staggered manner with their open faces facing the flow of flame.

The ash contained in the flame flowing in the horizontal flame path 10 collides with the V-shaped surfaces of these vertical members 21, 21', and is captured and flows downward. The vertical member 2
1, 21'... falls in the vertical duct 22 provided directly below, and the water tank 23 provided at the bottom of the vertical duct 22.
It falls inside and condenses into lumpy ash. 24 is a water replenishing means for replenishing water to the water tank 23, and 25 is a conveyor provided at the bottom of the water tank, which is a means for taking out lumpy ash. Further, by providing a convex member 26 on the upper part of the vertical duct 22, it is possible to block the horizontal flame duct 10 and the water tank 23 to some extent so that the temperature inside the horizontal flame duct 10 does not drop. According to this embodiment, the ash content in the flame can be removed to a higher degree, that is, about 98%, and the ash content in the second stage combustion chamber 11 can be reduced to about 2%.

[Summary] As explained above, according to the present invention, the combustion apparatus of the present invention creates a high-temperature hollow flame in the cyclone combustion chamber 1, which is the first stage combustion chamber, and burns the fuel such as pulverized coal containing a large amount of ash. 95% to 98% of the molten ash is removed by a baffle plate installed in the vertical flame path 16 or the horizontal flame path 10 as necessary, which leads the flame to the second stage combustion chamber 11. Second
In the stage combustion chamber, there is almost no ash content in the pulverized coal, and smooth combustion can be performed without the harmful ash content.

[Brief explanation of the drawing]

1 and 2 are overall configuration diagrams showing different embodiments of the present invention, and FIGS. 3 and 4 are partially enlarged side sectional views and enlarged horizontal sectional views of FIG. 2, respectively. 1...Cyclone combustion chamber, 2...Pulverized coal supply means,
3... Combustion aid supply means, 4... Primary air supply means, 5
...The squeezed part at the bottom of the cyclone combustion chamber, 6...
Water tank, 8, 9... lump ash removal means, 11... second stage combustion chamber, 12... biaxial air supply means, 15... convex member, 21, 21'... vertical member.

Claims (1)

[Claims] 1 A first stage combustion chamber of a cyclone combustion chamber is provided, and the cyclone combustion chamber is provided with a fuel supply means, a combustion aid supply means, and a primary air supply means consisting of an inner swirling flow from above and an outer swirling flow along the peripheral wall surface. and a constricted lower part, a vertical flame path below the constricted part, and a horizontal flame path on the side of the vertical flame path,
A baffle plate is provided in the flame path of the vertical flame duct, a water tank equipped with a means for removing lump ash is provided below the baffle plate, a second stage combustion chamber is provided at the front of the horizontal flame duct, and the combustion chamber A combustion device characterized in that a secondary air supply means is provided in the combustion device.