JP2527922B2 - Pulverized coal oxygen combustion burner - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention is for gasifying pulverized coal with pure oxygen or high-concentration oxygen in a high-temperature / reducing atmosphere and supplying it as high-temperature reducing gas to a gasification furnace / reaction tower, a combustion chamber of a boiler, and the like. The purpose is to provide a pulverized coal oxyfuel burner.

[0002]

2. Description of the Related Art FIG. 7 is a diagram showing an example of a first prior art.
It is a sectional side view of the burner for pulverized coal combustion described in Unexamined-Japanese-Patent No. 64-46514. In FIG. 7, 101 is a burner nozzle main body, 102 is an outer cylinder, 103 is an inner cylinder, and 104.
Is a pulverized coal supply pipe, 105 is a mixed flow jet, 106 is a combustion chamber, 107 is a flame jet, 108 is a combustion-supporting gas supply passage,
109 is a primary combustion-supporting gas supply path, 110 is a secondary combustion-supporting gas supply path, 111 is a cylindrical slit or a plurality of holes, 111a is a chamber for supplying secondary combustion-supporting gas, 112 Are a plurality of holes for supplying the secondary combustion supporting gas to the combustion chamber.

The burner nozzle body 1 in the prior art
01 indicates the inner cylinder 1 inside the outer cylinder 102 as shown in FIG.
03 is coaxially fitted, and inside the inner cylinder 103, an outlet 105 for a mixed flow of pulverized coal and a combustion-supporting gas (oxygen or oxygen-containing gas) is supplied from the pulverized coal supply pipe 104 on the upstream side. Combustion chambers 106 whose cross-sections gradually expand toward the downstream side are connected in series.

The pulverized coal fed through the pulverized coal supply pipe 104 is mixed with the primary combustion-supporting gas, enters the combustion chamber 106, and is fed in a plurality of stages in the axial direction of the burner. It burns while mixing with the secondary combustion supporting gas. At that time, the first
By appropriately selecting the inflow angle of the secondary combustion-supporting gas, the spread angle of the combustion chamber 106, the angle of the secondary combustion-supporting gas supply port, or the like, good ignition and stable combustion of the pulverized coal are performed. It is said that a high combustion temperature (about 2000 ° C.) can be obtained with high combustion efficiency.

[0005]

In addition, as a burner for burning finely pulverized solid fuel with a gas having a high oxygen content, Japanese Patent Laid-Open No. 59-89907 (second prior art) and Japanese Laid-Open Patent Publication No. Sho. There is a burner and the like described in Japanese Patent Laid-Open No. 59-56606 (third prior art), and these conventional technologies can also perform good ignition or combustion on pulverized solid fuel such as pulverized coal. Met. However, in the above-mentioned conventional technique, the fuel and the combustion-supporting gas are supplied to the furnace in a state of being accurately mixed in the burner (the above-mentioned second and third conventional techniques), or the fuel and the combustion-supporting gas are burned in the burner. In the state of being properly ignited with a proper gas and being surely ignited, the gas is supplied into the furnace (first prior art) for gasification and combustion.

However, in the above conventional technique,
Since pulverized coal in an unburned state or pulverized coal in a state where combustion has not been completed by ignition is ejected from the burner, a long reaction time is required, and a large facility in the gasification zone or combustion zone is required. There was a problem of becoming.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a burner capable of gasifying pulverized coal by a simple structure and supplying it as a high-temperature reducing gas.

[0008]

The above object is achieved by an oxyfuel combustion burner of pulverized coal as set forth in the appended claims. That is, (1) a pulverized coal nozzle, an oxygen nozzle, an ignition and preheating burner, and a burner main body having a water cooling jacket structure that axially penetrates a viewing window, and the burner main body is fitted into the burner main body, and the outer surface is covered with a water cooling wall structure. Pulverized coal oxyfuel combustion burner consisting of a pre-combustion chamber. (2) The pulverized coal oxyfuel combustion burner according to (1), wherein the pulverized coal nozzle is composed of a single tube or a plurality of tubes. (3) The oxyfuel combustion burner for pulverized coal according to (1), wherein the pulverized coal nozzle comprises a slit having an annular cross section in a direction perpendicular to the burner axis. (4) A viewing window, an ignition and preheating burner, and a pulverized coal nozzle are arranged in the center of the burner body, and a plurality of oxygen nozzles are arranged substantially evenly in the outer circumferential direction of the pulverized coal nozzle (1) or ( 2) Oxyfuel burner for pulverized coal as described. (5) A viewing window, an ignition and preheating burner are installed in the center of the burner body, a pulverized coal nozzle is provided outside the burner body, and a plurality of oxygen injection nozzles are provided on the burner center side and the burner outer periphery side from the pulverized coal nozzle. Are arranged almost evenly in the circumferential direction (1)
Or (2) or the oxyfuel combustion burner of pulverized coal according to (3). (6) At least one of the pulverized coal nozzle and the oxygen nozzle,
With means for swirling fluid in the circumferential direction of burner (1) or (2)
Or (3) or (4) or (5) oxyfuel combustion burner of pulverized coal. (7) Ignition and preheating burner capable of burning oil and slurry fuel (1) or (2) or (3) or (4) or (5) or (6) oxygen combustion of pulverized coal Burner. (8) A refractory material was provided on the inner surface of the pre-combustion chamber, and a self-coating structure with molten slag was used (1) or (2) or
(3) or (4) or (5) or (6) or (7) is an oxyfuel combustion burner of pulverized coal. Hereinafter, the operation and the like of the present invention will be described based on Examples.

[0009]

[Embodiment] Pulverized coal is gasified as much as possible before entering the coal gasification furnace or pulverized coal boiler furnace to minimize reaction time / combustion time in the gasification furnace main body or boiler furnace, and to make equipment compact. The present invention aims to provide an oxyfuel burner for reducing the cost and cost.

As a means for this, before the pulverized coal is fed into the furnace, the pulverized coal and a combustion-supporting gas such as oxygen are fed into an atmosphere having a temperature and a reducing temperature as much as possible, and it is possible to do it within an extremely short time. A method has been developed in which gasification is carried out and the gasified gas and char are mixed and fed into the furnace.

In order to gasify the above pulverized coal, in a general combustion furnace, the volume of the furnace is large and it is difficult to keep the ambient temperature in the furnace high. It is necessary to obtain a furnace having a size capable of contacting and reacting pulverized coal with oxygen to gasify the pulverized coal, while maintaining sufficient time for pulverized coal to be gasified.

FIGS. 1 to 6 are views showing an embodiment of the present invention made to achieve the above object, and FIG. 1 is an axial sectional view of a pulverized coal oxyfuel combustion burner in the first embodiment. 2 is a sectional view taken along the line aa in FIG. 1, FIG. 3 is a view taken along the line bb in FIG. 1, and FIG. 4 shows the burner body viewed from the side of the pre-combustion chamber in the second embodiment. FIG. 5 is a diagram showing the structure of the burner body in the third embodiment, and FIG. 6 is a view taken along the line cc in FIG.

1 to 6, 1 is a burner body, 2 is a pulverized coal nozzle, 3 is an oxygen nozzle, 4 is an oxygen header, 5 is an ignition and preheating burner, 6 is a sight glass, 7 is a cooling water pipe, and 8 is a cooling water pipe.
Is a cooling water inlet header, 9 is a cooling water outlet pipe, 10 is a water cooling jacket, 11 is a pre-combustion chamber, 12 is a water cooling jacket, 1
3 is a refractory material, 14 is a cooling water inlet pipe, 15 is a cooling water outlet pipe, 18 is a connecting flange, and 20 is a swirl vane.

First, the oxyfuel combustion burner for pulverized coal in the first embodiment will be described. As shown in FIGS. 1 to 3, the burner body 1 is composed of a pulverized coal nozzle 2, a plurality of oxygen nozzles 3, an ignition and preheating burner 5, a viewing window 6, a cooling water pipe 7, a water cooling jacket 10, and the like.

A pulverized coal nozzle 2 is arranged substantially in the center of the burner body 1, and a plurality of oxygen nozzles 3 communicating with an annular oxygen header 4 are evenly arranged in the outer circumferential direction thereof. Further, in the center of the burner body 1, the igniting and preheating burner 5 and the observation window 6 for monitoring the combustion state are arranged so as to be juxtaposed with the pulverized coal nozzle 2.
The pulverized coal nozzle 2, the oxygen nozzle 3, the ignition and preheating burner 5 and the peep window 6 are installed in the water cooling jacket 1
No. 0 outer tube plate and inner furnace end plate are inserted and attached by welding or the like.

A plurality of cooling water pipes 7 communicating with an annular cooling water inlet header 8 arranged outside are evenly inserted in the water cooling jacket 10 in the circumferential direction, and each cooling water pipe 7 is located inside the furnace of the burner body 1. The water-cooling jacket 10 is inserted through the water cooling jacket 10 to a position close to the inner wall of the pulverized coal and oxygen ejection side end. Further, a cooling water outlet pipe 9 is arranged at a position near the outer end of the water cooling jacket 10.

A pre-combustion chamber 11 is provided on the downstream side of the burner main body 1, and a part of the burner main body 1 is fitted thereinto to connect the connecting flange 1.
The burner body 1 is integrally connected by means of 8. The pre-combustion chamber 11 has a water cooling jacket 12 on the outside and a refractory material on the inside.

A plurality of cooling water inlet pipes 14 arranged in the circumferential direction of the pre-combustion chamber 11 are connected in the water cooling jacket 12 of the pre-combustion chamber 11, and each cooling water inlet pipe 14 is in the water cooling jacket 12. Is opened to the vicinity of the tip of the pre-combustion chamber 11, and the cooling water inlet pipe 1 of the water cooling jacket 12 is opened.
A cooling water outlet pipe 15 is arranged near the cooling water inlet portion of No. 4.

When gasifying pulverized coal using the oxygen combustion burner of pulverized coal having the above-mentioned structure, first, cooling water is supplied through the cooling water inlet pipes 7 and 14, and the water cooling jackets 10 and Cooling water is circulated in 12. Next, oil or LPG is supplied by the ignition and preheating burner 5.
Etc., and the temperature in the pre-combustion chamber 11 is sufficiently raised, and then the pulverized coal nozzle 2 produces pulverized coal and the oxygen nozzle 3
Oxygen is supplied to ignite and burn.

The inside of the pre-combustion chamber 11 has been sufficiently heated in advance by ignition and a preheating burner, and the pre-combustion chamber 11 is also heated.
Since the internal volume of the furnace is small, the supplied pulverized coal is burned by oxygen in a short time and the inside of the furnace becomes extremely hot. Along with that, combustion ash generated when pulverized coal is burned flows in a molten state in a state of being suspended in the combustion gas in the furnace. On the other hand, studs are preliminarily planted on the inner surface of the furnace of the pre-combustion chamber 11 over the entire inner surface of the water cooling jacket 12, and one end of each stud is cooled by the water cooling jacket 12. The combustion ash of (1) is cooled when it comes into contact with each stud, adheres and solidifies, and gradually grows until finally the entire inner surface of the pre-combustion chamber 11 is lined (self coating with slag).

The amount of oxygen ejected from the oxygen nozzle 3 is
By keeping the supplied pulverized coal at a value smaller than the amount required for complete combustion, the pre-combustion chamber 11 is kept in a reducing atmosphere, and the supplied pulverized coal becomes gasified gas and char. It is delivered from the tip in the separated high temperature state.

FIG. 4 shows the burner body 1 according to the second embodiment.
It is a figure which shows the structure of. In the embodiment, the ignition and preheating burner 5 and the sight glass 6 are provided at the center of the burner body 1.
And a slit-like pulverized coal nozzle 2 having a circular cross section in a direction perpendicular to the axis of the burner is disposed on the outer side of the burner. The nozzles 3 are evenly arranged in the circumferential direction.

5 to 6 are views showing the construction of the burner main body 1 according to the third embodiment. In the burner body 1 in the embodiment, an ignition and preheat burner 5 is arranged in the central portion, and a slit-like pulverized coal nozzle 2 having a circular cross section in the direction perpendicular to the axis of the burner is arranged outside the burner main body 1. A plurality of oxygen nozzles 3 are evenly arranged in the circumferential direction on both the inside and the outside of the annular slit-like pulverized coal nozzle 2.

The first feature of the third embodiment is that a plurality of swirl vanes 20 are inserted into an outer annular slit-like pulverized coal nozzle 2 to disperse the pulverized coal in the pre-combustion chamber 11. By swirling, the flying distance of the pulverized coal that moves while floating in the pre-combustion chamber 11 is increased, and the pulverized coal combustion is further activated.

Another feature of the third embodiment is that by arranging an oxygen nozzle between the ignition and preheating burner 5 and the pulverized coal nozzle 2, an oil is initially used as fuel for the ignition and preheating burner 5. Alternatively, stable combustion can be expected even if a gas such as LPG is used and the fuel injected from the ignition and preheating burner is switched from oil to slurry fuel such as CWM when the temperature in the furnace rises. .

In the third embodiment, the case where the pulverized coal nozzle 2 has an annular slit shape and swirl vanes are provided at the jetting portion thereof has been described. This is the case of the first and second embodiments. With respect to the tubular pulverized coal nozzle 2, the pulverized coal nozzle is provided with a swirl vane in the nozzle or by mounting the tubular pulverized coal nozzle 2 itself inclined with respect to the axis of the burner body 1. Needless to say, the same effect can be obtained even if the pulverized coal ejected from No. 2 is swirled in the pre-combustion chamber 11.

Further, not only the swirling force is applied only to the pulverized coal, swirl vanes are inserted in the oxygen nozzle 3 so as to swirl in the pre-combustion chamber 11, or the oxygen nozzle 3 itself is attached to the burner body. It can be expected to further increase the effect by swiveling the oxygen ejected from the oxygen nozzle 3 in the pre-combustion chamber 11 by mounting the slanting member with respect to the axis of No. 1 and also in the swirling direction of the pulverized coal and oxygen. The action and effect can be further enhanced by changing the turning speed and the like.

[0028]

According to the present invention, as described in the above embodiment, the following effects can be obtained. The burner, which has an extremely simple and compact configuration, accurately gasifies pulverized coal in a short time and continuously supplies it to various furnaces such as a boiler furnace and a coal gasifier in the state of high temperature and strongly reducing atmosphere gas and char. It becomes possible to do. Since the burner body and the pre-combustion chamber have a water cooling jacket structure made of steel, the pressure inside the furnace can be increased and the gasified gas and char can be discharged at a very high speed.

[Brief description of drawings]

FIG. 1 is an axial sectional view of an oxyfuel combustion burner for pulverized coal according to a first embodiment of the present invention.

FIG. 2 is a sectional view taken along the line aa in FIG.

FIG. 3 is a view taken along the line bb in FIG.

FIG. 4 is a view of the burner body viewed from the side of the pre-combustion chamber in the second embodiment according to the present invention.

FIG. 5 is a diagram showing a configuration of a burner body in a third embodiment according to the present invention.

FIG. 6 is a view taken along line c-c in FIG.

FIG. 7 is a side sectional view of a pulverized coal combustion burner according to a conventional technique.

[Explanation of symbols]

1 Burner Body 2 Pulverized Coal Nozzle 3 Oxygen Nozzle 4 Oxygen Header 5 Ignition and Preheating Burner 6 Peep Window 7 Cooling Water Pipe 8 Cooling Water Inlet Header 9 Cooling Water Outlet Pipe 10 Water Cooling Jacket 11 Pre-Combustion Chamber 12 Water Cooling Jacket 13 Refractory 14 Cooling Water Inlet pipe 15 Cooling water outlet pipe 18 Connection flange 20 Swirling blade 101 Burner nozzle body 102 Outer cylinder 103 Inner cylinder 104 Pulverized coal supply pipe 105 Mixed flow jet pipe 106 Combustion chamber 107 Flame jet 108 108 Burning gas supply passage 109 Primary Combustion-supporting gas supply path 110 Secondary combustion-supporting gas supply path 111 Cylindrical slit 111a Chamber for supplying secondary combustion-supporting gas 112 A plurality of secondary combustion-supporting gas supplies communicating with the combustion chamber Hole

Claims (8)

(57) [Claims] 1. A pulverized coal nozzle, an oxygen nozzle, an ignition and preheating burner, and a burner main body having a water cooling jacket structure in which an observation window is axially penetrated, and the burner main body is fitted therein, and an outer surface thereof is a water cooling wall structure. An oxyfuel combustion burner of pulverized coal characterized by comprising a pre-combustion chamber. 2. The pulverized coal oxyfuel combustion burner according to claim 1, wherein the pulverized coal nozzle is composed of a single tube or a plurality of tubes. 3. The oxyfuel combustion burner for pulverized coal according to claim 1, wherein the pulverized coal nozzle comprises a slit having an annular cross section in a direction perpendicular to the axis of the burner. 4. A viewing window, an ignition and preheating burner, and a pulverized coal nozzle are arranged in the center of the burner body, and a plurality of oxygen nozzles are arranged substantially evenly in the outer circumferential direction of the pulverized coal nozzle. The oxyfuel combustion burner of pulverized coal according to claim 1 or 2. 5. A viewing window, an ignition and preheating burner are provided in the center of the burner body, a pulverized coal nozzle is provided outside the burner body, and a plurality of oxygens are provided on the burner center side and the burner outer periphery side from the pulverized coal nozzle. The oxygen combustion burner for pulverized coal according to claim 1, 2 or 3, wherein the blowing nozzles are arranged substantially evenly in the circumferential direction. 6. At least one of the pulverized coal nozzle and the oxygen nozzle has a fluid swirling means in the circumferential direction of the burner, wherein the fluid swirling means is provided in the circumferential direction of the burner. An oxyfuel combustion burner of pulverized coal according to 5. 7. The ignition and preheating burner is capable of burning oil and a fuel in a slurry state, claim 1 or claim 2 or claim 3 or claim 4.
Alternatively, the pulverized coal oxyfuel combustion burner according to claim 5 or claim 6. 8. A refractory material is provided on the inner surface of the pre-combustion chamber to form a self-coating structure using molten slag, claim 1 or claim 2, claim 3 or claim 4 or claim 5 or claim 5. An oxyfuel combustion burner for pulverized coal according to claim 6 or 7.