JPH10130651A - Method for removing carbon deposit from inside of coke oven - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a simple method for removing carbon deposit from the inside wall in the upper space of a carbonization chamber and to provide a method for operating a coke oven, whereby the removal of carbon deposit can be facilitated. SOLUTION: This invention provides a method for removing carbon deposit comprising forming an easily peelable layer 2 made of an inorganic material on the inside wall in the upper space of a coke oven on which carbon is apt to deposit in carbonizing coal and separating the carbon deposit 3 on the easily peelable layer together with the part of the easily peelable layer after the carbonization and a method for operating a coke oven comprising performing the formation of an easily peelable layer made of an inorganic material and the separation of the carbon deposit 3 from the easily peelable in every one to several cycles of coal carbonization in the period between the time of coke oven pushing and the time of coal feed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for removing carbon deposited in a coke oven, and more particularly to an inner wall portion of an upper space of a coking chamber to which carbon is likely to adhere, in particular, a lower inner wall of a riser pipe and an inner wall of a coal hole. The present invention relates to a method for removing carbon deposited and attached to a portion or the like.

[0002]

2. Description of the Related Art At present, in the operation of a coke oven, a major problem in operation is the blockage of the inner wall portion of the coke oven carbonization chamber, particularly in the vicinity of the lower inner wall of the riser, due to the adhesion of carbon. It is a removal operation. Conventional measures against such a problem are roughly classified into four methods. The first one is to install a rotary cutter and mechanically cut deposited carbon as seen in Japanese Patent Publication No. 7-194420. However, this method has a problem that the refractory material constituting the inner wall of the furnace is often damaged during cutting.

[0003] Second, as disclosed in JP-A-3-212486, a gas containing water or carbon dioxide gas is blown into the upper space during carbonization of coal to lower the ambient temperature. This suppresses the carbonization reaction itself. However, this method has a problem that a large coke oven requires a large amount of equipment investment and management burden since it is necessary to individually control and blow gas into hundreds of carbonization chambers and risers.

[0004] Third, as seen in JP-A-7-268330, attention is paid to the fact that carbon is flammable.
By introducing excess air, it is burned off. However, in this method, the deposited carbon has a graphite structure in many cases, and it takes time until the carbon is burned out, and there is a problem that the operation rate of the coke oven is reduced. In addition, the operator working on the coke oven comes close to the open flame, and the working environment becomes poor.

[0005] Fourth, as disclosed in JP-A-4-31378, a coating is applied to the surface of the inner wall to make it difficult for carbon to adhere. However, even this method does not eliminate the adhesion. Further, the coating may be peeled off by collision of hard fine particles such as coke powder. Then, if carbon is attached at one place, carbon starts to be precipitated from there as a nucleus. Because of these problems,
In the coke oven, there is still work left for operators to remove manually.

[0006]

The inventors of the present invention believe that the mechanism of carbon deposition is that during coal distillation, the tar component in the gas becomes heavy and adheres to the surface of the refractory material on the inner wall of the furnace, where the carbon is deposited. Growing, refractory (brick)
It has been found that the carbon deposited on the top penetrates into the pores of the brick and is thus firmly bonded. SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a simple method for removing carbon which is deposited on the inner wall portion of the upper space of the carbonization chamber during coal distillation and adhesion is inevitable.

[0007]

Means for Solving the Problems The present inventors have studied to solve such problems, and as a result, it is difficult to completely prevent adhesion since carbon is supplied infinitely from coal. Since the violent riser itself is also a consumable, it was judged economically inappropriate to incorporate a removal / prevention device for each riser. Then, the present inventors have arrived at the idea that improving the removability of adhering carbon and reducing the work load is the most effective solution to the problem.

That is, according to the present invention, when the coal is dry-distilled in a coke oven, an easily peelable layer substantially made of an inorganic substance is formed on the inner wall portion of the upper space of the carbonization chamber where carbon tends to adhere. This is a method for removing carbon deposited in a coke oven, characterized in that carbon adhered on the easy layer is dropped together with at least a part of the easy peel layer.

In the method of removing carbon deposited in a coke oven according to the present invention, the easily peelable layer is formed by spraying inorganic fine particles which are not sintered in a dry distillation together with a binder to the inner wall portion or fixing a thermosetting resin binder. It is preferable that the impregnated inorganic fiber thin layer is pressed and fixed to the inner wall portion. Further, the inner wall portion on which the easily peelable layer is formed is an upper space of the carbonization chamber, and is preferably near the riser pipe portion and near the coal hole, particularly preferably near the lower inner wall of the riser tube.

Further, when the coal is subjected to dry distillation in the coke oven of the present invention, coal charging, carbonization, and coke oven discharge are performed in one step.
In the operation of the coke oven as a cycle, the formation of the easily peelable layer on the inner wall of the furnace and the removal of the carbon adhered on the easily peelable layer are removed between the time of leaving the coke oven and the time of charging new coal. It may be performed every cycle, or may be performed every two to three cycles.

Hereinafter, the present invention will be described in detail. The easily peelable layer made of an inorganic substance formed in the present invention is fixed to the inner wall portion of the upper space of the carbonizing chamber by spray coating means or the like so that the layer does not easily fall off at the temperature of the carbonizing chamber during the dry distillation and the gas velocity of the coke oven. On the other hand, in the removing operation (such as scraping) after the carbon is deposited, the fine particles or the inorganic fibers are easily separated from each other and fall off together with the precipitated carbon. From such a viewpoint, as a member for forming the easily peelable layer substantially composed of an inorganic substance used in the present invention, an inorganic fine particle is fixed with a binder, or an amorphous substance composed of inorganic fibers formed in a layered form, Various modes such as a pre-molded one are possible. However, practically, it is preferable that inorganic fine particles are sprayed together with a binder and fixed to form a layer.

The inner wall portion on which the easily peelable layer is formed may be in the upper space of the carbonization chamber, but is particularly preferably near the lower portion of the riser tube inner wall (including the ceiling inner wall portion around the rising base). Here, it is not necessary to form the entire surface of the inner wall of the riser tube, and it is sufficient that carbon is usually most easily adhered, for example, within a range of about 1.5 to 1.6 m from the rising base to the upper part. As the inorganic fine particles, those which do not sinter themselves due to the hot air of the gas passing through the riser or the radiant heat from the carbonization chamber are preferable. When these inorganic fine particles and inorganic fibers are mutually sintered, they are strongly bonded to the inner wall of the furnace, making it difficult to peel off.Conversely, if cracks occur due to coagulation shrinkage, gas It may easily fall off even by hot air, and in any case, it may not be possible to easily remove the attached carbon, which is the object of the present invention, from the inner wall of the furnace.

From this viewpoint, examples of the inorganic fine particles include silica, alumina, coke or pitch coke, and carbon black. Particularly preferred inorganic fine particles are pitch coke powder in terms of economy. In addition, it is also possible to pulverize and use the same type of material as the refractory material constituting the furnace inner wall, which contributes to the use of waste materials of the refractory material.
The particle size range of the inorganic fine particles is selected in consideration of the releasability and the coating property, and is preferably in the range of 10 to 1000 mesh. As the inorganic fibers, for example, a thin layer made of inorganic fibers such as a blanket made of short fibers such as ceramic fibers and a tape made of long fibers can be used.

As the binder, silicone oil, water glass, thermosetting resin such as phenolic resin, tar, pitch and the like can be used, and those which are uniformly mixed with inorganic fine particles as appropriate can be used. In particular, the binder is necessary to have a minimum adhesiveness between the inorganic fine particles and the inner wall of the furnace. The optimum values for the type and particle size of the inorganic fine particles and the selection of the binder vary depending on the operating conditions of the coke oven (such as gas wind speed) and the furnace structure (such as the diameter of the riser). When a phenol resin is used as the binder and the pitch coke powder having a particle size of 2 mm or less, the binder is preferably used within a range of 2 to 10 parts by weight based on 100 parts by weight of the inorganic fine particles.

As a specific fixing method, inorganic fine particles (containing a binder) may be slurried with water or the like and sprayed. It is also possible to atomize with a gas such as air, water vapor or nitrogen gas. Alternatively, it may be applied. The thickness of the easily peelable layer fixed to the inner wall of the furnace by spray coating means or the like to such an extent that it does not easily fall off is, for example, 2 to 2.
It is good to make it 20 mm. If the thickness exceeds 20 mm, it takes a long time for drying, and it tends to be easily peeled off due to shrinkage, etc., whereas if it is less than 2 mm, uniform coating is difficult, and the attached carbon penetrates to the inner wall of the furnace and falls off. It will be difficult. However, it also depends on the coating method and the like.

The method of removing the carbon adhering on the easily peelable layer together with at least a part of the easily peelable layer is not particularly limited, and a conventional cleaning means is sufficient. For example, a manual scraper, a high-pressure gas spray, or a scraper rotating with compressed air known in Japanese Utility Model Laid-Open No. 5-77234 can be suitably used. In addition, as a mechanical cleaning device, a rotary cutter (Japanese Patent Publication No. 7-11942) installed on the frame of a loading car, extruder, coke guide car, etc.
No. 0), a fluid blow-out pipe that can move up and down
-103448) can be used.

The formation of the easily peelable layer made of an inorganic substance and the removal of carbon from the carbon in the coke oven in the coke oven operation method in which the coke oven is charged with coal, dry-distilled, and removed from the coke oven in one cycle are formed by removing the coke that has been carbonized. It is preferably carried out between the time of leaving the kiln and the time of charging new coal. It is preferable that the formation of the easily peelable layer and the removal and removal of carbon are performed in the same cycle. If only carbon removal is performed, the base (brick) comes out and carbon adheres to the base. The frequency of the formation of the easily peelable layer and the removal and removal of carbon attached thereto may be performed every cycle, or may be performed every two to three cycles.

[0018]

Embodiments of the present invention will be described below. FIG. 1 shows a state in which carbon 3 is adhered on a releasable layer 2 formed by laminating inorganic powders to each other on a refractory layer 1 on the inner wall of a riser tube to which carbon easily adheres in a coke oven. FIG. 2 shows a partially stripped state of the attached carbon 3. First, in FIG. 1, the easy-peeling layer 2 is formed before the start of coal carbonization by refractory layer 1 on the inner wall of the riser pipe.
The carbon adhering to the surface is cleaned and removed by a conventional method, and the deposited carbon adhering is removed to such an extent that gas flow is not hindered. Next, inorganic fine particles are sprayed together with a binder and fixed so as to substantially cover the refractory layer 1 on the inner wall portion to which carbon is likely to adhere. The spray spraying operation is preferably performed manually or by a mechanical action from the canopy release portion of the riser tube or the sheet cleaner machine frame side of the furnace lid released in the coke oven. The sprayed inorganic powder becomes the easily peelable layer 2.

When coke is subjected to dry distillation in this state, carbon precipitated from the gas phase adheres to the easily peelable layer 2 as the carbon layer 3. After several carbonization cycles, the carbon layer 3 grows to such an extent that the operation is not hindered and the riser is clogged. At the end of the cycle, the operator scrapes the riser from the open part of the canopy as shown in FIG. The deposited carbon layer 3 is pushed down together with the easily peelable layer 2 by using a take-off rod 4 or the like. In this case, unlike the conventional case, instead of scraping off only the deposited carbon layer 3 firmly attached to the inner wall portion of the carbonization chamber, the deposited carbon is removed by an easily peelable layer (at least at least) composed of inorganic fine particles formed gently on the inner wall of the furnace. The scraping operation can be completed easily and in a short time since the scraping operation may be performed together with the part 2). After the end of the carbon removing operation, a fresh easy-peeling layer 2 ′ of inorganic powder is again placed thereon.
And the operation can be resumed.

FIG. 3 is a conceptual diagram showing a case where an easily peelable layer in which an amorphous material made of an inorganic fiber is formed in a layered form is fixed to the vicinity of the base of the inner wall of a rising pipe. For example, a cloth-like amorphous material (blanket) 5 of an inorganic fiber is impregnated with a thermosetting binder, and the bottom inner wall surface of the riser tube and the vicinity 6 of the base ceiling are formed.
It is pressed and fixed by a pressing jig 7 using a mechanical lifting means provided on a machine frame of an extruder, a coke guide wheel or the like. What is necessary is just to heat-harden and fix the irregular-shaped thing 5 according to the shape of an inner wall surface from the vicinity of the ceiling part of a base. Also in this case, carbon precipitates on the surface of the amorphous material, so that the precipitated carbon can be removed together with the amorphous material 5. As the amorphous material, for example, a blanket made of short fibers of ceramic fiber, a tape made of long fibers, or the like can be used.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Specific embodiments of the present invention will be described below.

Example 1 The effect of the present invention was evaluated using a test coke carbonization apparatus. The test furnace and operating conditions used were the same as the furnace used by Shiromoto, Matsuoka, and Ota described in Fuel Society Journal, Vol. 48, No. 510 (1969), page 732, and the coal charge was 250 kg.
It is. As the riser section, a straight pipe having a diameter of 150 mm was used. The coal used is coal used in-house with a volatile content of 26% and a water content of 5%. The distillation temperature is 900 ° C and the temperature of the riser is 700
Tested at ~ 1000 ° C. The effective distillation time was 7 hours.

Silica powder slurried with silicone oil was applied to the inner wall of the riser tube using a spray gun using compressed air so that no coating was left behind. As shown in FIG. 1, an easily peelable layer of silica fine particles (25 cm from the base) was used. To a height of 2 to 3 mm). Average particle size of silica powder 2
At 00 mesh, the amount formed was about 2 kg / m ² . When the carbonization operation was repeated three times, 2 times from the base of the riser of the riser.
Since it was confirmed that carbon was deposited and adhered on the easily peelable layer over a height of 0 cm, the distillation was stopped. As shown in FIG. 2, when the lump of precipitated carbon was pierced from above with a scraping rod made of SUS, the lump of carbon was easily dropped together with the easily peelable layer made of silica fine particles. The attached amount was about 4 kg / m ² .

Example 2 Instead of spraying silica powder in Example 1, one side of a ceramic wool blanket (6 mm thick) was spray impregnated with a phenol resin as a binder (100 g /
m ² ) Example 1 except that a cylindrical easy-peeling layer was formed and cured and fixed by pressing the impregnated surface against a preheated riser as shown in FIG. The experiment was performed under the same conditions as described above. When the carbonization operation was repeated three times, it was found that carbon was deposited and adhered on the tubular exfoliation-prone layer inside the riser tube, so it was pierced with a SUS scraping rod from above the riser tube. At that point, the blanket fell along with the attached carbon. The amount of carbon attached was almost the same as in Example 1. Some ceramic fiber blanket remained on the inner wall of the riser itself, but no carbon was attached.

Comparative Example 1 A coke carbonization test was performed three times using the same apparatus as in Example 1 except that treatment such as application of silica powder was not performed. The amount of attached carbon was almost the same (3.5 kg),
In this example, the carbon is firmly attached to the refractory material constituting the inner wall, and it is necessary to use a chisel for removal,
It took time to work.

[0026]

According to the present invention, carbon produced in the gaseous phase in the upper space of the conventional coke oven carbonization chamber, especially in the gas phase in the riser, is intensively laminated in molecular size on the inner wall of the riser and near the rising base thereof. Precipitated carbon is dense and furnace wall (such as riser)
Because of the close contact with the irregularities of the refractory material, the adhesive force between the two is strong due to the anchor effect, and they are not easily peeled off.
According to the method of the present invention, since the easily peelable layer is previously formed on the refractory material of the furnace inner wall, the adhesive force between the furnace inner wall and the deposited carbon can be reduced. If you can increase the peelability,
Even in the case of scraping off carbon with a scraping rod, the refractory material is not damaged and the life is extended. Further, since the work can be performed in a short time, there is an effect that the work efficiency is improved.

[Brief description of the drawings]

FIG. 1 is a conceptual diagram showing an easy-peeling layer formed on an inner wall of a riser tube and a deposition state of carbon adhered thereon.

FIG. 2 is a conceptual diagram showing a state in which attached carbon is dropped.

FIG. 3 is a conceptual diagram in a case where an easy-peeling layer made of inorganic fibers is fixedly attached near a base portion of an inner wall of a rising pipe.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Refractory layer of riser pipe inner wall 2 Easy peeling layer 3 Adhered carbon 4 Scraping rod 5 Inorganic fiber-like irregular shaped material 6 Near base of riser pipe 7 Pushing jig

Claims (4)

[Claims] When a coal is subjected to dry distillation in a coke oven, an easily peelable layer substantially made of an inorganic substance is formed on an inner wall portion of the upper portion of the carbonization chamber where carbon is likely to adhere. A method for removing deposited carbon in a coke oven, wherein the attached carbon is dropped together with at least a part of the easily peelable layer. 2. The method for removing carbon deposited in a coke oven according to claim 1, wherein the easily peelable layer is formed by spraying inorganic fine particles that are not sintered in the dry distillation together with a binder onto the inner wall portion. 3. The method for removing carbon deposited in a coke oven according to claim 1, wherein the easily peelable layer is formed by pressing and fixing an inorganic fiber thin layer impregnated with a thermosetting resin binder to an inner wall portion. . 4. The method for removing carbon deposited in a coke oven according to claim 1, wherein the peelable layer is formed near the lower inner wall of the riser.