JPS5939323A - High temperature dust collecting apparatus - Google Patents

Abstract

PURPOSE:To certainly carry out the removal of fine dust in high temp. combustion gas and the desulfurization and the deodorizing of said gas, by passing the combustion gas issued from a particular fuel combustion apparatus through a dust removing chamber filled with CaCO3, magnesia lime or the like. CONSTITUTION:A dust removing chamber 2 is filled with particulate substance 7 such as CaCO3, magnesia lime or the like on the perforated plate 6 made of a refractory material provided therein. Particulate coal fuel blown into fuel blow-in chamber 11 from a supply pipe 36 is brought to a stirred and floated state by the air stream from a supply pipe 35 to be preheated by a preheating pipe 21 and the preheated fuel enters a combustion chamber 12 through the upper communication part 20 of a partition wall 17 to be ignited. Combustion gas is injected into the cyclone dust collecting apparatus 14 in a combustion gas outtake chamber 13 through the preheating pipe 21 and, after dust therein is fallen and separated into a dust collecting chamber 25, the dust removed gas is supplied to the introducing chamber 1 of a dust collecting apparatus C through the exhaust cylinder 26 and the combustion gas outtake pipe 8 of a shaft part. Fine dust in the combustion gas is adsorbed and removed by the particulate material 7 in the dust removing chamber 2 and the desulfurization and the deodorizing of said gas is performed while the clean odorless combustion gas is sent to hot air machinery from a final combustion gas discharge pipe 3.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a high-temperature dust collector used in connection with a granular fuel combustion device.

Are there calls for a review of coal and other solid fuels due to concerns about oil supply?
Alternatively, it is difficult to obtain high firepower with a simple device. Among these, so-called fluidized bed combustion, in which solid fuel is granulated (pulverized) and then combusted while being agitated and floated, is attracting attention as a combustion method that solves the above problems. We have applied for patents for various solid fuel combustion devices inspired by fluidized bed combustion.

These solid fuel combustion devices are generally able to achieve good combustion, but it is difficult to remove even the finest dust from the final combustion gas, especially in applications where dust is a concern. Dust is a problem. A so-called bag filter is known as a high-temperature filter, but this bag filter does not have heat resistance to high temperatures of 280°C or higher, and cannot be used in the above-mentioned combustion equipment where combustion gas reaches 1000°C. .

The present invention was made based on such a technical background, and focuses on the dust adsorption, desulfurization, and deodorizing effects of calcium carbonate, magnesium lime, and other solid substances, and has been developed to reduce The combustion gas t1 is characterized by passing through a dust removal chamber filled with calcium carbonate, etc., to purify the combustion gas more reliably. Calcium carbonate can be used as a waste product from lime factories.
The present invention will be described below with reference to the illustrated embodiments.

In FIGS. 1 and 2, B indicates a solid fuel combustion device, and C indicates a high-temperature dust collector according to the present invention. This dust collector C consists of a cloth layer combustion gas introduction chamber'/, a dust removal chamber '/, and a final combustion gas extraction pipe 3 which are arranged in sequence from the bottom, and each of these chambers or pipes is formed at each end. The flanges lα and koα, 2b and 3α are connected together with a port nara) 1 via a heat-resistant sealing material g'6.

At the lower end of the dust removal chamber, a perforated plate made of fire-resistant material is installed either integrally or removably.
In addition, granules 7 that adsorb fine powder contained in the combustion gas are filled. Particle size 7 The particle size should be determined taking into account the stacking thickness, pressure loss, adsorption efficiency, etc., but for example, 5 to 2.
A diameter of about 0m+φ can be used.

A combustion gas take-off pipe of the combustion device B is connected to the combustion gas introduction chamber 1, and a final combustion gas take-off pipe 3 is connected to a hot air device such as a dryer.

Therefore, in the present dust collector C having the above configuration, after solid fuel is combusted in the combustion device B, when the combustion gas is blown into the introduction chamber L through the combustion gas tray outlet pipe of the fabric layer, the combustion gas is It passes through the plate 6 and enters the dust removal chamber 3, passes through the gaps between the granules 7, and further rises, whereupon the dust is removed. That is, particulate matter 7
Due to its adsorption action, fine dust (ash) in the combustion gas is adsorbed and removed, and at the same time, it is desulfurized and deodorized.
The combustion gas supplied from the take-out pipe to the hot-air equipment contains almost no fine powder and is clean and odorless.

When the adsorption power of particulate matter 7 decreases (portonara)'
It is sufficient to remove the dust removal chamber 2 from the introduction chamber/and take-out pipe, discard the old granules inside, and fill with new granules. As mentioned above, calcium carbonate can be made from lime factory waste, so conversion costs and operating costs can be kept low, and since it turns into quicklime when heated, it has sufficient ash adsorption and desulfurization effects. can be expected. Furthermore, similar effects can be expected by using magnesia lime as the granular material. Note that the dust collector C of the present invention is not limited to the configuration of the combustion device B;
The combustion device shown in the embodiment has a high dust collection effect in itself and is suitable for burning cohesive fuel, and is highly effective in combination with the dust collection device C of the present invention. Therefore, this combustion device B will be explained next.

This combustion device B includes a fuel injection chamber /l in the center, a combustion chamber /U provided on one side (right side in FIG. 1) of the injection chamber /l, and
It has a combustion gas extraction chamber 13 provided on the other side (the same left side),
A cyclone dust collector l≠ is disposed within the combustion gas extraction chamber/3 with a gap maintained between it and the surroundings. Above room //, /J
are horizontally cylindrical with their axes horizontal, and the chamber 13 has a shape suitable for a vertical cyclone dust collector l≠, and includes an outer shell /j made of a refractory material, an end wall 16, and a partition wall t'y.
, it, etc. /ri is a cooling water or cooling air circulation pipe embedded in the outer shell /j, /! ? α.

/Pb are its inlet and outlet.

The upper part of the partition wall 17 between the fuel injection chamber /l and the combustion chamber l- is cut out to form a communication locus θ between the two chambers. A preheating pipe is installed. This preheating tube 21 has one end connected to the end wall 16 of the combustion chamber/co.
The other end passes through the fuel injection chamber //f and opens in the upper tangential direction of the outer cylindrical body 3 of the cyclone dust collector.

Cyclone dust collector／≠ means outer cylindrical body, 2
The lower part of the outer cylindrical body 3 is formed as a diameter-reducing part that gradually reduces in diameter, and a dust collection chamber asf is connected to the lower part of the diameter-reduced part. Since the preheating tube 21 is open in the tangential direction of the outer cylindrical body 23, the combustion gas blown into the cylindrical body flows into the cylindrical body 23 in a spiral shape, and dust with heavy specific gravity moves to the outside and is separated from the gas. The gas falls into the dust collection chamber below, and the gas from which the dust has been removed is then led to the shaft exhaust pipe roller. The exhaust pipe g communicates with the combustion gas extraction chamber 13, and the combustion gas extraction pipe g opens at an appropriate position in the combustion gas extraction chamber 13.

As is clear from FIG. 5, the fuel injection chamber l/ has an air supply pipe 3j extending downward in the tangential direction of the cylindrical injection chamber, and a fuel supply pipe 36 slightly above the air supply pipe 3j. It's open. As shown in FIG. 5, the fuel supply pipe 36 is sequentially connected to the fuel mixing pipe 3 of the fuel storage pot 37 and to the blower 3.
A conveyance screw≠l driven by a motor (FIG. 6) is inserted, and the rotation of this screw guides the granular (powder) fuel in the hopper 37 into the fuel supply pipe 3.

The amount of fuel supplied can be adjusted by changing the rotational speed of the conveying screw 4Z/, and the amount of air can be adjusted by the opening degree of the flow regulating valve ≠ -! It can be adjusted.

In addition, an air supply pipe 3j of fuel injection chamber/l is connected to the combustion chamber/co.
Similarly, the air supply pipe≠3. ≠
j is open. These air supply pipes 33, l
, ≠t are on-off valves≠6. ≠7. It is connected to the blower 3F via the cable.

Further, an ignition flame introduction pipe r/ opens into the combustion chamber /. The most upstream end of this introduction pipe is connected to the blower 3F via an on-off valve j, and a gas cylinder rs is connected in the middle thereof via an ejector j3 and an on-off valve tg. This ignition device mixes ignition gas and air using an ejector j3 and ignites the mixture using a spark plug 56.
The ignition flame is ejected from the entire introduction pipe j/ into the combustion chamber/J. Note that the codes 37, 31. j? are each room/
l, /ko.

60 indicates a temperature sensor provided on the end wall/6 of the combustion chamber/2.

In the combustion device B having the above configuration, when the blower 3 and the drive device 110f of the fuel storage hopper 37 are driven simultaneously, the coal-based granular fuel including the tar basin flows from the fuel supply pipe 3t to the fuel injection chamber/
/ is blown out, and this is stirred by the air flow from the air supply pipe 3j to form a vortex. Since the air supply pipe 3j opens near the outlet of the fuel supply pipe 36, the granular fuel is effectively stirred and floated.

The granular fuel thus stirred and floated enters the combustion chamber l- through the upper communication port 2Of provided in the partition wall/7, is strengthened by the vortex flow by the air flow from the 32 air supply pipes, and arrives at the combustion chamber l-. It is ignited by the ignition gas from the flame introduction pipe j/. Therefore, combustion in a fluid state is started, and the combustion gas passes through the preheating pipe 1'(il-) and is ejected to the cyclone dust collector/≠ in the combustion gas extraction chamber/3. The heavier fuel is located on the outer side due to the centrifugal force of the vortex flow, and the lighter gases that are combusted enter the preheating tube, allowing for more complete combustion.

When the above combustion is carried out steadily, the temperature of the preheating tube 1 becomes high, and therefore the temperature of the fuel blowing chamber // also becomes high. This combustion device B utilizes this heat to preheat the coagulated coal-based granular fuel containing tar before combustion. That is, when the fuel is heated, the tar contained in the fuel is gasified, and the granular fuel, which was a caking substance, changes to a non-caking substance. Chemically, this change corresponds primarily to carbonization of coal-based fuels in the pre-combustion process.

The heating temperature in the fuel injection chamber /I varies depending on the surface area of the preheating tube /I, the residence time of the granular fuel, etc., and these factors are appropriately set to enable the carbonization to be carried out.

In particular, the length and thickness of the preheating tube, 2/2, and the size of the communication port 2o are major factors.

Therefore, the steady combustion that takes place in the combustion chamber /,2 is
Since the process is carried out using granular fuel whose properties have been changed to non-caking, the possibility of foreign matter adhering and accumulating on the /jth wall surface, the wall surface of the preheating tube col, etc. is extremely reduced.

The combustion gas that has entered the Zylon collection device/≠ from the preheating tube 21 falls into the dust collection chamber 2j and is separated by the action of the swirling gas flow and the dust's own weight as described above, and then is discharged from the details. The combustion gas enters the combustion gas extraction chamber/3 from the cylinder 2B, and is supplied to the combustion gas introduction chamber 1 of the dust collector C of the present invention via the combustion gas extraction pipe.

The exhaust pipe and 2Aij may be directly connected to the combustion gas extraction pipe, but if the combustion gas extraction chamber 13 is provided and communicated with this as shown in the example shown, the extraction pipe g can be opened at any position in the extraction chamber 13. This has the advantage of being able to

Since combustion in the combustion chamber takes place in a vortex,
The agitation and floating state of fuel can be maintained for a long time.

Combustion in such a fluid state is known to reduce the generation of NOZ and Soz, and can therefore contribute to the prevention of air pollution.

Another advantage is that low quality coal with high ash and sulfur content can be used.

When the temperature in the combustion chamber exceeds approximately 800℃, the presence of a small amount of water and oxygen (combustion air) causes a water gasification reaction according to the following reaction equation, which makes it easier to burn pulverized coal and causes the combustion chamber wall surface to It is known that the temperature does not rise above the melting temperature of ash.

HzO+C-+CO+Ht CO±H, +C, →co*+n,.

Furthermore, if a small amount of water can be supplied to the fuel injection chamber l/, the temperature of the second wall surface can be adjusted.

For this reason, this combustion device has an inspection viewing window 37. The water supply pipes &J-, A& connected to the tank 6t are opened through the on-off valves 6/, 62 to the Kl, so that a small amount of water can be supplied to each chamber. In particular, the opening/closing valve 12 of the water supply pipe 66 connected to the combustion chamber 12 is fully controlled by a temperature sensor 10 facing the combustion chamber, thereby preventing the combustion chamber 12 from reaching an abnormal cylinder temperature. is preferable. In addition, there is an inspection window! 7,
ji, evening? The reason why the small amount air supply pipes Ap, 70, and 7/, which are connected to the blowers 3, are opened in order to prevent the windows from fogging up.

To summarize, the high-temperature dust collector according to the present invention allows the combustion gas emitted from the granular fuel combustion device B to pass through the bed filled with granules such as quicklime and magnesia lime through the introduction chamber and the dust removal chamber. Even if the combustion gas is at a high temperature, it is possible to remove minute dust from the combustion gas by utilizing adsorption chips of particulate matter.
Desulfurization and deodorization can be carried out reliably, and therefore, it is suitable for use in applications where the combustion gas source is particularly sensitive to fine leaflet dust.

[Brief explanation of the drawing]

FIG. 1 is a vertical cross-sectional view showing an embodiment of a high-temperature dust collector and granular fuel combustion device according to the present invention, FIG. 2 is a system connection diagram showing a cross-sectional perspective view of the same part, FIGS. 3 and 4, 5 is a sectional view taken along line 1--2, line 2-tv, and line V-V in FIG. 1, and FIG. 6 is a sectional view taken along line MM in FIG. 2. C... High temperature dust collector, B... Granular fuel combustion device, /
... Combustion gas introduction chamber, 2 ... Dust removal chamber, 3 ... Final combustion gas extraction pipe, j ... Bolt nut, t ... Perforated plate, 7 ... Calcium carbonate, g ... Combustion Gas take-off pipe, ll... fuel injection chamber, /, 2... combustion chamber, /≠・
・・Cyclone dust collector, −〇・・Communication port, edge・・
Preheating tube.

Claims (1)

[Scope of Claims] (1) A high-temperature dust collector to be installed downstream of a granular fuel combustion device, which includes a combustion gas introduction chamber to which a combustion gas extraction pipe of the combustion device is connected, and this introduction chamber. A dust removal chamber is connected to the upper part of the dust removal chamber with a heat-resistant perforated plate interposed in between, and a final combustion gas extraction pipe is connected to the upper end of the dust removal chamber. 1. A high-temperature dust collector characterized by being filled with granular material that adsorbs fine powder contained therein. (2. In claim 1, the combustion device includes a horizontally cylindrical fuel injection chamber into which granular fuel is injected, and a horizontally cylindrical combustion chamber having an ignition device provided on one side of the fuel injection chamber. a vertical cyclone dust collector provided on the other side of the fuel injection chamber, a communication port opened at the top of the partition between the fuel injection chamber and the combustion chamber, and a vertical cyclone dust collector provided on the other side of the combustion chamber and the combustion chamber. A high-temperature dust collector, which has a preheating pipe that passes through the fuel injection chamber and communicates with the dust device, and a combustion gas extraction pipe is provided downstream of the vertical cyclone dust collector. (3) Scope of Claims The high-temperature dust collector according to item 1 or 2, wherein the dust removal chamber is detachable from the combustion gas introduction chamber and the final combustion gas extraction pipe, and the calcium carbonate inside is replaceable.