WO2011030730A1 - Lubricant for oven floor of coke oven carbonization chamber - Google Patents

Abstract

Disclosed is a lubricant for the oven floor of a coke oven carbonization chamber, which can be easily spread on the oven floor of a coke oven carbonization chamber and can largely reduce the load on an extruder when coke is extruded from the carbonization chamber after the completion of the carbonization. A lubricant to be spread on the oven floor of a coke oven carbonization chamber before supplying coal thereto, which has a pyrometric cone equivalent of SK12 or higher and is composed of ceramic spheres, the major part of the spheres having a particle diameter of 1-15 mm. It is desirable that the inclination angle of the aforesaid lubricant, at which the lubricant having been in the stationary state starts to move, is 10^o or below.

Description

Coke oven coking chamber hearth slip agent

TECHNICAL FIELD The present invention relates to a hearth slip agent that is laid on the hearth of a carbonization chamber prior to charging coking coal in order to reduce the load when extruding coke after completion of carbonization from the carbonization chamber in a coke oven. It is.

The coke oven has a structure in which a carbonization chamber for carbonizing coal into coke and a combustion chamber for burning fuel gas to heat the carbonization chamber are arranged alternately, and a partition wall between the carbonization chamber and the combustion chamber Refractory brick is used.
The carbonization chamber is an elongated rectangular closed space, and the coal that has been carbonized therein is extruded from the carbonization chamber to the discharge side by an extruder, and is extinguished and cooled to become product coke. For this reason, the width of the carbonization chamber is set to be slightly wider on the discharge side in order to facilitate the extrusion of coke after the dry distillation.

However, the refractory bricks that become the partition walls gradually become rough due to friction with the input coal and coke after dry distillation, and further due to thermal fatigue due to repeated heating and cooling, and the frictional resistance increases. Therefore, even though the width on the discharge side is wide, the load by the extruder may be increased or clogging may occur, which has been an operational problem.

Therefore, in order to reduce the frictional resistance between the hearth of the carbonization chamber and coke at the site, before putting the coal, a wooden board is laid on the hearth and carbonized with the coal, between the hearth and coke, By forming a carbonized layer of wood, it has been attempted to improve the slipperiness of coke and reduce the load on the extruder.
In addition, the refractory repair agent that falls during the repair of the furnace wall is received by the granular refractory material spread over the hearth, preventing the increase in the load on the extruder due to the repair agent adhering to the hearth and roughening the hearth surface. There has also been a proposal to reduce the load at the time of coke extrusion due to the sliding effect when the granular refractory collapses (see Patent Document 1).

JP 2003-238965 A

However, in a method in which a wooden board is laid on the hearth and carbonized together with coal, the work of laying the wooden board must be done manually by humans, which is dangerous and requires a long working time. Further, in the coke oven with a rough hearth, clogging occurred similarly, and a satisfactory sliding effect could not be obtained.
On the other hand, in the method of spreading the granular refractory, as a measure against dust generation at the time of charging, the particulate refractory material is granulated to 0.3 to 10 mm. It is easily disintegrated by receiving a force from the side, and exhibits slipperiness by becoming an original fine particle state (10 μm or less). Therefore, even if it can prevent the roughness of the hearth surface due to adhesion of a repair agent such as mortar to some extent, it cannot be said that it is difficult to spread evenly on the entire surface of the hearth and does not accumulate locally. In some cases, there is a problem that the load on the extruder increases.

The present invention has been made in view of such problems of the prior art, and the object of the present invention is that it can be easily laid on the hearth of a coke oven carbonization chamber and coke after completion of dry distillation. It is an object of the present invention to provide a slipping agent that can significantly reduce the load on the extruder during extrusion.

As a result of intensive studies to achieve the above object, the present inventors have demonstrated that an aggregate of relatively coarse-grained ceramic spherical particles exhibits an excellent function as a coke oven hearth slip agent. The headline and the present invention have been completed.

That is, the coke oven coking chamber hearth slip agent of the present invention is a slip agent spread on the hearth of the coke oven carbonization chamber prior to the introduction of coal, and has a fire resistance of SK12 or more and a particle size of 1 to 15 mm. It consists of a ceramic spherical body mainly composed of a diameter.

According to the present invention, the spheroid is made of a ceramic material having a fire resistance of SK12 or more, and is made of an infinite number of spheres mainly having a particle size of 1 to 15 mm. By subjecting the coal to carbonization in a state where it is spread on the hearth, the load on the extruder can be reduced when the obtained coke is extruded.

(A) It is a schematic explanatory drawing which shows the measuring point of the coke pushing force in the Example of this invention. (B) It is a top view which shows the state of the chamotte brick spread | laid on the bottom face of the model carbonization chamber shown to Fig.1 (a). It is a graph which shows the relationship between the application quantity of each sliding agent by the Example and a comparative example, and the extrusion force of coke. It is the schematic which shows the shape of the actual coke oven carbonization chamber used for the Example of this invention. It is a graph which shows the measurement result of the extrusion load by Example 16 and Comparative Example 8 using an actual coke oven carbonization chamber.

Hereinafter, the coke oven carbonization chamber hearth slip agent of the present invention will be described in more detail along with its production method and the like. In the present specification, “%” means mass percentage unless otherwise specified.

As described above, the coke oven carbonization chamber hearth slip agent of the present invention is made of a ceramic spherical body having a particle size mainly in the range of 1 to 15 mm and a fire resistance of SK12 or more. It can be introduced from the upper coal charging entrance.
Since the slip agent has a relatively large spherical shape, when it is thrown in, it bounces on the hearth and spreads over the entire hearth, and it is only necessary to throw it in from the inlet of the carbonization chamber to spread the slip agent evenly. Even if it is not performed, it can be spread evenly, reducing the time and improving the safety of work.

The particle diameter of the coke oven carbonization chamber hearth slip agent of the present invention is mainly 1 to 15 mm. That is, if the particle size of the slip agent is smaller than 1 mm, the friction between the slip agents increases, and the load on the extruder during coke extrusion discharge increases. On the other hand, if the particle size is larger than 15 mm, there is a possibility of causing damage to the hearth when thrown into the carbonization chamber. Therefore, the particle size of the slip agent needs to be 1 to 15 mm. A more preferable range of the particle size of the slip agent is 3 to 10 mm.
The “particle diameter” as used herein means an average value of the major axis and the minor axis of the ceramic spherical body constituting the slip agent.

The particle size of the hearth slip agent of the present invention is in the range of 1 to 15 mm for the reasons described above. However, since it is an industrial product, the particle size is less than 1 mm and more than 15 mm even if classified by a predetermined sieve. It does not necessarily mean that the spherical body is not mixed slightly. In this case, it has been confirmed that if the mixture of spherical bodies outside the predetermined particle size range does not exceed 2% by mass ratio, the performance as a slipping agent is hardly affected. In the present invention, “mainly having a particle diameter of 1 to 15 mm” means that spherical bodies having a particle diameter of 1 to 15 mm occupy 98% or more.

In order for the slipping agent of the present invention to spread uniformly over the entire hearth of the carbonization chamber, the repose angle of the slipping agent is 40 degrees or less, and further, the slipping agent is placed on a horizontal base. When the base is tilted, it is desirable that the tilt angle when the slip agent starts to move is as small as 10 degrees or less.

The angle of repose of the above-mentioned slipping agent was set to 40 degrees or less. If it was larger than 40 degrees, when it was introduced from the inlet of the carbonization chamber, it piled up directly under the inlet to create a mountain and increase the load during extrusion. Because there is a tendency to end.
The angle of repose can be measured according to the method defined in JIS R 9301-2-2. However, the above method stipulates that a funnel having an inner diameter of 6 mm is used, but in the case of a slip agent having a particle size larger than this, it is necessary to use a nozzle having an inner diameter corresponding thereto. Become.

If the tilt angle expressed by the angle at which the slip agent begins to move when tilted from a state where it is placed on a horizontal base is less than 10 degrees, the slip agent introduced from the carbonization chamber inlet is directly below the inlet. It rolls before making a mountain, and is distributed over the whole hearth without being piled up in a mountain shape so that it can be spread evenly.
For the measurement of the tilt angle, the glass plate is tilted to an arbitrary angle, and a spherical body is slowly placed on the glass plate. The body was tested with an arbitrary number, and the angle of the glass plate when the number moved was more than half was taken as the inclination angle.

Regarding the sphericity of the individual spherical bodies constituting the slip agent of the present invention, when the sphericity is expressed by the ratio of the major axis (D _L ) to the minor axis (D _S ) (D _S / D _L ), this ratio Is preferably 0.9 or more. If the sphericity is less than 0.9, the slipping agent has a rugby ball shape, the rolling direction is limited, and good slipperiness tends not to be exhibited. In addition, it is more preferable that it is 0.95 or more.

The fire resistance of the slipping agent of the present invention is desirably SK12 (1350 ° C.) or higher.
When the fire resistance is lower than SK12, it cannot be said that the surface of the slipping agent does not soften when carbonizing coke, and in such a case, the surface is not sticky and cannot exhibit slipperiness. It may cause clogging. The fire resistance is more preferably SK18 (1500 ° C.) or higher.

Furthermore, the strength of the slipping agent, that is, the crushing strength of the individual ceramic spherical bodies is preferably 90 N or more, and more preferably 500 N or more. If the crushing strength is less than 90 N, the crushing strength tends to be lost due to crushing at the time of coke charging or extrusion.

As a raw material used for manufacturing the hearth slip agent for the coke oven of the present invention, materials containing general refractory components such as SiO ₂ , Al ₂ O ₃ , ZrO ₂ , TiO ₂ , for example, silica sand, silica, alumina Powder, zircon sand, rutile sand, kaolinite, chamotte (baking viscosity), talc and the like can be used.
In particular, kaolinite, which is a hydrated silicate mineral of aluminum, is well known as a porcelain material, and by increasing its content, a fired product that can withstand high temperatures can be made.

In addition to the above, the raw materials for the slip agent include binders such as alkali metal compounds, alkaline earth metal compounds and iron compounds, specifically sodium silicate, sodium metasilicate, sodium aluminate, potassium silicate, Potassium metasilicate, magnesium oxide, magnesium carbonate, calcium oxide, calcium carbonate, iron (III), iron oxide (II, III), boric acid, sodium borate, sodium phosphate and sodium silicate glass powder, borosilicate glass A frit component such as powder is blended.

The composition of the coke oven hearth slip agent of the present invention is SiO ₂ : 45 to 88 mass%, Al ₂ O ₃ : 10 to 48 mass%, and other components: 2 to 7 mass%. It is preferable from the point.
Here, if SiO ₂ is less than 45% by mass and Al ₂ O ₃ exceeds 40% by mass, the melting point of the slip agent becomes high, and the firing temperature has to be increased, which makes production difficult. On the other hand, when SiO ₂ exceeds 88% by mass and Al ₂ O ₃ is less than 10% by mass, the strength of the spherical body constituting the hearth slip agent becomes small, and it breaks at the time of coke charging and exhibits excellent slipperiness. It may not be possible.

The other components are components other than SiO ₂ and Al ₂ O ₃ , components derived from the bonding agent such as Na ₂ O and K ₂ O, and SiO ₂ and Al in the raw material including the bonding agent. _This means the total amount of impurity components other than ₂ O ₃ , but if the additive amount of the bonding agent becomes excessive and the other components exceed 7% by mass, the fire resistance decreases, and heat is generated when coke is distilled off. The slip agent melts or stickiness occurs on the surface of the slip agent, and the slip agents stick to each other, and not only the slip property cannot be exerted but also cause clogging.
On the other hand, when the added amount of the bonding agent is small and the other components are less than 2% by mass, the fire resistance is increased, but the crushing strength is decreased due to insufficient bonding components, and it is easily pulverized and exhibits a sliding effect. There is a tendency to become impossible.

The slip agent of the present invention is not particularly limited as long as it has a predetermined fire resistance and is made of a ceramic spherical body having a predetermined particle diameter, and includes TiO ₂ and ZrO ₂ . However, it is difficult to avoid an increase in raw material cost for those containing a large amount.
Therefore, as described above, an inexpensive and practical composition is SiO ₂ : 45 to 88% by mass, Al ₂ O ₃ : 10 to 48% by mass, and other components: 2 to 7% by mass, preferably SiO 2: ₂ : 67 to 75% by mass, Al ₂ O ₃ : 19 to 30% by mass, and other components: 3 to 6% by mass.

In the present invention, the above-described compounds are used as the bonding agent, and these compounds are detected as Si, Al, Na, K, B, etc. in the analysis of the sintered ceramic spheres. However, Si and Al are transferred to the main component as SiO ₂ and Al ₂ O ₃ . On the other hand, Na, K, B, Mg, Ca, and Fe are converted into Na ₂ O, K ₂ O, B ₂ O ₃ , MgO, CaO, and Fe ₂ O ₃ for convenience.
In the present invention, “other components” means components other than SiO ₂ and Al ₂ O ₃ as described above, and components derived from the binder as described above and components derived from impurities of the raw material. The total amount.

Hereinafter, the present invention will be described in more detail based on examples and comparative examples, but it goes without saying that the present invention is not limited to these examples.

[Manufacture of hearth slip agent]
Sliding agent 1 (Invention example)
Raw materials mainly composed of zirconium silicate are put in a mixer, rotated while spraying water, granulated, dried, baked at 1300 ° C, and classified using 6 mesh and 7 mesh sieves. As a result, ceramic spherical bodies mainly composed of ZrO ₂ as shown in Table 1 were produced, and the slip agent 1 corresponding to the present invention was obtained.
At this time, sodium silicate was used as a binder.

Lubricant 2 (Invention example)
Using raw materials mainly composed of rutile sand and kaolinite, granulation and firing in the same manner as the above-mentioned slipping agent 1, and classification using 3 1/2 mesh and 4 mesh sieve, Table 1 A ceramic spherical body containing TiO ₂ as a main component as shown in the above is prepared and used as the slip agent 2 corresponding to the present invention. At this time, sodium silicate was used as a binder.

Sliding agent 3 (Invention example)
As shown in Table 1 by granulating in the same manner using raw materials mainly composed of kaolinite and alumina powder, firing at 1850 ° C., and classifying using 6 mesh and 9 mesh sieves. Ceramic spheroids mainly composed of Al ₂ O ₃ and SiO ₂ were prepared and used as the slip agent 3 corresponding to the present invention. At this time, potassium silicate was used as a binder.

Lubricant 4 (Invention example)
Using raw materials mainly composed of kaolinite and silica sand, granulation, baking, and classification using 9 mesh and 16 mesh sieves as in the case of the slip agent 1, Ceramic spheroids mainly composed of SiO ₂ and Al ₂ O ₃ were prepared and used as the slip agent 4 corresponding to the present invention. As a binder, sodium silicate was used.

Sliding agent 5 (Invention example)
Except for the use of 3 mesh and 4 mesh sieves, the same operation as in the case of the slip agent 4 is repeated, thereby producing ceramic spherical bodies mainly composed of SiO ₂ and Al ₂ O _3. The slip agent 5 corresponding to At this time, sodium silicate was used as a binder.

Sliding agent 6 (comparative example)
As shown in Table 1 by granulating in the same manner using raw materials mainly composed of kaolinite and alumina powder, firing at 1850 ° C., and classifying using 35 mesh and 42 mesh sieves. A spherical body made of ceramics mainly composed of Al ₂ O ₃ and SiO ₂ was prepared as a slip agent 6 not corresponding to the present invention, and used as a comparison agent with the present invention. At this time, sodium silicate and magnesium carbonate were used as binders.

(Measurement of particle size)
The particle size was measured for each slip agent prepared as described above. In measuring, the spherical bodies constituting each slip agent are taken with a digital camera together with a metal ruler, enlarged and printed out, and the major and minor diameters of the spherical bodies of the image and the scale of the ruler are measured with a caliper. Each major axis and minor axis were determined from the ratio between the scale and the vernier caliper value, and the average value was taken as the particle size of the spherical body.

[Measurement of repose angle]
The angle of repose of each slipping agent prepared as described above was measured using a powder funnel having a nozzle with an inner diameter of 14 mm in accordance with JIS R 9301-2-2.
The distance from the tip of the funnel foot to the base was set to 40 mm as in the above standard. However, when the height of the mountain exceeded 40 mm, the height of the funnel was gradually increased and adjusted so that the top of the mountain did not hit the funnel. The results are also shown in Table 2.

[Measurement of tilt angle]
On the glass plate inclined at an arbitrary angle, the spherical bodies constituting the respective slip agents obtained as described above were gently placed, and it was observed whether or not the spherical bodies rolled out. And 20 said spherical bodies which comprise each slip agent were observed, and the angle of the glass plate when the number which moved became the half was made into the inclination angle.
The results are also shown in Table 2.

(Measurement of fire resistance)
Spherical bodies constituting each slip agent prepared as described above are pulverized, mixed with water and kneaded, molded according to JIS R 8101 (1999), with two sizes of Zeger corn, dried, and then fire resistance is increased. It was measured. The results are also shown in Table 2.

[Measurement of sphericity]
About 10 spherical bodies constituting each slip agent adjusted as described above, 10 are arbitrarily extracted, and the maximum diameter (D _L ) and the minimum diameter (D _S ) are determined by the same method as the measurement of the particle diameter described above. The average value of the ratio (D _S / D _L ) was calculated to obtain the sphericity. The results are also shown in Table 2.

(Measurement of crushing strength)
Ten spherical bodies were arbitrarily extracted from each of the slipping agents adjusted as described above, and the crushing strength was measured by a compression test, and the average value was taken as the crushing strength of the slipping agent.
The results are also shown in Table 2.

[Measurement of extrusion force by simulation test]
In order to measure the coke extrusion force when each slip agent obtained as described above was used, a carbonization chamber model was prepared and tested in the following manner.

That is, FIG. 1A is a schematic diagram of the apparatus used in the test, in which reference numeral 1 is a forklift, 2 is a load cell for load measurement, 3 is an extrusion plate, 4 is coke, and 5 is model carbonization. Each shows a chamotte brick SK-32 spread on the bottom of the chamber.
As the carbonization chamber, a tin plate is attached to the bottom and side surfaces of a metal frame having a width of 0.25 m, a length of 1.8 m, and a height of 0.6 m, and the tin plate on the bottom surface is as shown in FIG. Further, the chamotte brick 5 was laid diagonally.

As shown in FIG. 1 (a), the load cell 2 of the digital force gauge is fixed to the tip of the claw of the forklift 1, and each slipping agent is spread on the chamotte brick 5 and then the coke 4 is reduced to about The coke 4 was moved by pushing the extrusion plate 3 by advancing the forklift 1 by moving 50 kg, and the pressure applied to the extrusion plate 3 at that time was measured by the load cell 2.

(Examples 1 to 3)
On the chamotte brick 5 of the model carbonization chamber, the slip agent 1 (ZrO ₂ system, particle size: 2.79 to 3.33 mm) prepared as described above was 2 kg / m ² , 5 kg / m ² and 10 kg / m ^{2, respectively.} After laying down, about 50 kg of coke 4 was placed thereon, and the force required when the coke 4 was pushed out by the forklift 1 was measured by the load cell 2.

(Examples 4 to 6)
On the chamotte brick 5 in the model carbonization chamber, the slip agent 2 prepared as described above (TiO ₂ system, particle size: 4.70 to 5.61 mm) is similarly laid, and the force required to extrude the coke 4 is similarly applied. It was measured.

(Examples 7 to 9)
On the chamotte brick 5 of the model carbonization chamber, the slip agent 3 prepared as described above (Al ₂ O ₃ —SiO ₂ system, particle size: 1.98 to 3.33 mm) is spread in the same manner, and it is necessary to extrude the coke 4. The measured force was measured similarly.

(Examples 10 to 12)
On the chamotte brick 5 of the model carbonization chamber, the slip agent 4 prepared as described above (SiO ₂ —Al ₂ O ₃ system, particle size: 1.00 to 1.98 mm) is spread in the same manner, and it is necessary to extrude the coke 4. The measured force was measured similarly.

(Examples 13 to 15)
The slip agent 5 (SiO ₂ —Al ₂ O ₃ , SiO ₂ Al ₂ O ₃ system, particle size: 4.70 to 6.68 mm) prepared as described above is similarly spread on the chamotte brick 5 in the model carbonization chamber. The force required to extrude the coke 4 was measured in the same manner.

(Comparative Example 1)
50 kg of coke 4 was placed directly on the chamotte brick 5 in the model carbonization chamber without spraying the slip agent, and the force required for the extrusion was measured in the same manner.

(Comparative Examples 2 to 4)
On the chamotte bricks 5 of the model carbonization chamber, slipping agent prepared by the above _{6 (Al 2} O 3 -SiO 2 system, particle size: 0.35 ~ 0.42 mm), respectively ^{2kg / m 2, 5kg / m} 2 Then, 10 kg / m ^{2 was} spread and about 50 kg of coke 4 was placed thereon, and the force required for the extrusion was measured in the same manner.

(Comparative Examples 5 to 7)
In order to grasp the current situation of using wooden boards, charcoal particles of 1.68 to 4.70 mm are placed on the chamotte brick 5 in the model carbonization chamber at 2 kg / m ² , 5 kg / m ² , 10 kg / m ^{2 was} spread, about 50 kg of coke 4 was placed thereon, and the force required to push the coke 4 was measured by the same method.
The above measurement results are also shown in Table 3 and FIG.

As a result, it was found that the result of the extrusion force of the slip agent was the order of slip agent 5 ≧ slip agent 3> slip agent 2> slip agent 1> slip agent 4 >> slip agent 6 ≧ charcoal >> comparative example 1. .
The slip agents 1 to 5 (Examples 1 to 15) of the present invention exhibit very excellent slip performance as compared with Comparative Examples 1 to 7. Among these, it was confirmed that the slip agents 5, 3 and 2 are particularly excellent.

[Measurement of extrusion force in actual machine test]
Furthermore, in order to measure the coke extrusion load in accordance with the actual operation, tests were conducted in the following manner using the carbonization chamber of the actual coke oven.

That is, FIG. 3 is a schematic view of an actual coke oven carbonization chamber used in the actual machine test, in which reference numeral 11 denotes a coal charging inlet, 12 denotes a hearth, and 13 denotes an extruder.
The carbonization chamber has a furnace width M / S: 0.388 m, C / S: 0.452 m, a furnace height of 6.85 m, and a furnace length of 15.9 m.

(Example 16)
Before putting coal into the actual coke oven carbonization chamber, 15 kg of the slip agent 5 from each of the four coal inlets in the upper portion of the carbonization chamber, 60 kg in total, was charged. The introduced slip agent 5 bounced greatly due to the impact dropped on the hearth of the carbonization chamber, spread over the whole surface of the hearth, and was uniformly sprayed.
After the slip agent 5 was charged, 32t of coal was charged from the four coal inlets at the top of the carbonization chamber, carbonized at 1200 ° C for 19.5 hours, and the coal that had been carbonized was extruded from the carbonization chamber with an extruder. The load (peak ampere) applied to the extruder was measured.
A test similar to the above was performed a total of nine times by changing the coke oven carbonization chamber, and the average value was obtained.

(Comparative Example 8)
The same test as in Example 16 was performed using the same coke oven as in Example 16 without introducing a slipping agent, and the load (peak ampere) applied to the extruder was measured.
The above measurement results are shown in Table 4 and FIG.

From the above extrusion measurement results, as shown in Table 4, it was confirmed that the slip agent 5 was put into the carbonization chamber to be in a uniform spray state on the hearth surface, reducing the extrusion load after dry distillation. As a result, it has been found that it exhibits very good sliding performance.

Claims (6)

1. Coke oven coking chamber hearth characterized in that it is a slip agent spread on the hearth of a coke oven carbonization chamber, and has a fire resistance of SK12 or more and is made of a ceramic spherical body mainly having a particle size of 1 to 15 mm. Slip agent.
2. The coke oven carbonization chamber hearth slip agent according to claim 1, wherein the repose angle is 40 degrees or less.
3. The coke oven coking chamber hearth slip agent according to claim 1 or 2, wherein an inclination angle from the stationary state to the start of movement is 10 degrees or less.
4. 4. The sphericity expressed by the ratio (D _S / D _L ) between the major axis D _L and the minor axis D _S of the spherical body is 0.9 or more, Coke oven carbonization chamber hearth slip agent according to item.
5. The coke oven carbonization chamber hearth slip agent according to any one of claims 1 to 4, wherein the crushing strength of the spherical body is 90 N or more.
6. The Si component contains 45 to 88% by mass in terms of SiO ₂ , the Al component in terms of Al ₂ O ₃ contains 10 to 48% by mass, and the other components contain 2 to 7% by mass. 6. The coke oven carbonization chamber hearth slip agent according to any one of 1 to 5.

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