JP6562218B2 - Coke oven coal charging method - Google Patents

Description

  The present invention relates to a method for charging coal in a coke oven in which coal is charged from a charging hole into a carbonization chamber of a chamber-type coke oven, and in particular, coal charging in a coke oven when 100% of coal is used as a raw material. Regarding the method.

  As a facility for producing coke used in a blast furnace, a chamber-type coke oven (hereinafter simply referred to as “coke oven”) is used. The coke oven is composed of combustion chambers spaced apart in parallel in the furnace width direction and a carbonization chamber provided between the combustion chambers. A plurality of usually 4 to 5 charging holes are arranged on the ceiling of the carbonizing chamber of the coke oven, and the raw coal is charged into the carbonizing chamber through the charging hole. The coke is produced by dry distillation by supplying heat generated by burning gas in the combustion chamber to the carbonization chamber via a refractory.

  Coke used in the blast furnace is required to have high cold strength and hot strength in order to withstand impact during transportation to the blast furnace and friction during flow drop in a high-temperature atmosphere in the blast furnace. . Therefore, caking coal that melts and caking during dry distillation is used as the raw material coal. However, caking coal is about 10% of coal that can be mined in the world and is expensive. Therefore, from the viewpoint of effective use of resources and from the viewpoint of reducing coke production costs, it has been studied to use steam coal with low caking property as a raw material in a coke oven. As one of the methods, a technique has been developed in which coking coal obtained by molding steam coal is used as coking coal for coke ovens.

  The coking coal blending method of charging coking coal containing coking coal from above into the carbonization chamber of the coke oven has been industrialized since the 1970s, and is a process that can be easily implemented simply by attaching the coal making facility to existing coke production facilities. As a result, it spreads rapidly and plays a major role in improving coke quality and reducing manufacturing costs. On the other hand, cast charcoal is produced by combining pulverized coal with a binder and has a problem of being easily pulverized by impact.

  In particular, when charging the coal into the carbonization chamber of the coke oven, it is impacted and powdered by dropping about 5 to 8 m corresponding to the furnace height of the carbonization chamber. When coking coal is pulverized in a coke oven, the bulk density of the charging coal is partially excessive, and there is a problem in that the coke obtained after dry distillation has increased load during coke extrusion and poor dry distillation.

  In order to avoid such coal pulverization, Patent Document 1 uses coal coal and pulverized coal, and after only putting pulverized coal at 30 mass% to 60 mass% of the total amount of coal, the remaining amount is pulverized coal. A method of charging as a mixture of coal is proposed.

JP-A-1-178589

  However, the method of Patent Document 1 is a method in which blended coal is mixed and charged with coal, and is a method premised on the use of expensive blended coal, from the viewpoint of effective use of resources, and coke production. Improvement has been demanded from the viewpoint of cost reduction.

  Accordingly, an object of the present invention is to achieve effective use of resources and reduction of coke production cost without causing an increase in coke extrusion load and poor carbonization even when only coal is charged into a coke oven. Is to propose a new method for charging coal in a coke oven.

  As a result of intensive investigations on the above-mentioned problems of the prior art, the inventors dropped the coal directly into the bottom of the carbonization chamber when charging the coal into the carbonization chamber of the coke oven from the charging hole. Compared with the case where (1) the pulverized coal generated by the falling of the charcoal turns, for example, diffuses to just below the adjacent charging hole, and (2) the charging charcoal is placed at the bottom of the carbonization chamber with a cushion. The present invention was developed by ascertaining that there was less pulverization of the charcoal if the charcoal was charged via an object (preceding charcoal or pulverized charcoal).

  That is, the present invention is a coke oven coal charging method for charging only coking coal into a coking oven carbonization chamber through a plurality of charging holes provided in the ceiling of the carbonization chamber. Select every other charging hole, charge a part of the total charcoal charging amount, and then, from the other charging holes not selected, out of the total charcoal charging amount Further, the present invention lies in a coal charging method for a coke oven, characterized in that a part is charged and then the remaining part of the total charging amount of the coal is charged using all charging holes.

In addition, in the coal charging method of the coke oven of the present invention configured as described above,
(1) First, a part of the total charging amount of the charcoal charged through the selected charging hole is 15 mass% to 35 mass% of the total charging amount, and then from the other charging holes. A part of the total charging amount of the charcoal to be charged is 15 mass% to 35 mass% of the total charging amount, and the charcoal to be charged thereafter is an amount corresponding to the balance of the total charging amount. about,
(2) When the coke oven has four charging holes, the first charcoal is charged from the first and third charging holes from the machine side or the coke side, When charging is performed from the second and fourth charging holes, and the coke oven has five charging holes, the first charging of charcoal is performed first from the machine side or the coke side, 3rd and 5th, and the next charcoal charge is second and fourth or vice versa,
(3) In the charging of the first charcoal, the charging of the second charcoal, and the charging of the last charcoal, the amount of charcoal to be charged each time is charged each time. Divide into the entrance holes in equal parts,
Is considered to be a more preferable solution.

  According to the present invention configured as described above, a part of the total amount of charcoal charging is obtained from the charging holes that are not adjacent to each other among the plurality of charging holes arranged in a row, for example, every other charging hole. First, charge a part of the remaining charcoal charge from another charge hole different from the charge hole used earlier, and then charge all the remaining charcoal. Since it is a method of charging using a hole, even when only coking coal is charged into a coke oven, it does not cause an increase in coke extrusion load or poor dry distillation, and more effective use of resources and A reduction in coke production costs can be achieved.

It is a figure which shows an example of the simulated carbonization chamber used in order to investigate the pulverization behavior of the forming charcoal at the time of the charging of the charcoal to the coke oven as a premise of the present invention. It is a figure which shows the powdering rate of each site | part in a simulation carbonization chamber. It is a figure for demonstrating the state which inserted the charcoal equally from each charging hole simultaneously according to the prior art example. It is a figure for demonstrating the state which injected | thrown-in only the charcoal from each charging hole according to this invention by dividing timely and appropriate quantity into 1 to 3 times.

  First, as a premise for considering the method of charging coal in the coke oven of the present invention, the pulverization behavior of the forming coal at the time of charging the forming coal into the coking chamber of the coke oven was examined. Specifically, the pulverization behavior of the coal was investigated when the coal was charged from the charging hole into the carbonization chamber of the coke oven.

  That is, FIG. 1 is a diagram showing an example of a simulated carbonization chamber used for investigating the pulverization behavior of coal when only coal is charged into a coke oven. In the example shown in FIG. 1, 1 is a simulated carbonization chamber, 2 is a sampling port provided at a plurality of locations (here 32 locations) on the side of the simulated carbonization chamber 1, and 3 is a charging provided at the top of the simulated carbonization chamber 1 The holes 4 are formed charcoal hoppers that communicate with the charging hole 3. The simulated carbonization chamber 1 has a height (H) of 7520 mm, a length (L) of 3020 mm, and a width (W) of 430 mm.

  This simulated carbonization chamber 1 simulates the actual machine size of the carbonization chamber. Charcoal is charged from one charging hole 3 and fed from the bottom to the top of the simulated carbonization chamber 1. Later, by sampling the coal formed in each part of the carbonization chamber from a plurality of sampling ports 2 provided on the side surface of the simulated carbonization chamber 1, the pulverization rate of the coal in each part where the sampling port 2 exists is investigated. can do.

  As the charcoal used in the present invention, a carbonaceous material such as caking coal or non-caking charcoal was added with a binder, kneaded with a molding machine, and adjusted to a crushing strength of 170 kg / piece. The shape of the charcoal was a Macek type of 44 mm × 44 mm × 31 mm.

  In the investigation, the above-mentioned coal was charged into the carbonization chamber from the charging hole 3 of the simulated carbonization chamber 1, and the pulverization rate of the coal was extracted from each sampling port 2, and this is shown in FIG. Here, the pulverization rate was obtained by sieving each sample with a 15 mm square sieve and expressed as a percentage of the mass under the sieve with respect to the sample mass.

  As is clear from the results shown in FIG. 2, the powdering rate is lower in the vicinity of the bottom of the carbonization chamber furnace immediately below the charging hole 3 as compared with the high powdering rate of about 20 mass%. I understand that. It can also be seen that the powdering rate of the sample collected from the sampling port 2 adjacent immediately below the charging hole 3 is much lower than that of the sample immediately below the charging hole 3.

  Such a tendency of the pulverization rate is thought to be because the falling coal at the bottom of the furnace directly below the charging hole 3 is more likely to be pulverized by colliding with a hard furnace bottom refractory, and has already been formed. In the case where it is possible to avoid a direct collision with the furnace bottom refractory, the pulverization is mitigated by the collision of the coal at the top of the pile of the deposited coal and the falling coal. This is probably because of this. On the other hand, in the region adjacent immediately below the charging hole, the charged coal is deposited by flowing into both sides, so it is considered that the influence of the collision is small.

  Considering this result, when charging coal into the carbonization chamber, if simultaneous charging is performed from each charging hole as in the past, as shown in FIG. 3, immediately below each charging hole, as shown in FIG. It can be seen that the cast charcoal to be charged into is subjected to pulverization of about 20 mass%, and this portion has a large amount of powder, so that the bulk density rises and becomes a factor of increasing the load at the time of coke extrusion.

  Therefore, in the present invention, when a plurality of (for example, 4 to 5) charging holes are provided on the ceiling of the carbonization chamber, two charging holes that are not adjacent to each other, that is, every other charging hole, are provided. From 3 or more, after first charging a portion of the total coal charge, preferably 15 mass% to 35 mass% in 2 to 3 minutes, then from other charging holes not used Also, it was decided that a part of the total coal charge, preferably 15 mass% to 35 mass%, was charged, and finally, the remaining cast charcoal was charged in an equal amount if possible using all the charging holes.

  For example, in the case of a carbonization chamber in which four charging holes are arranged on the ceiling of the carbonization chamber, as shown in FIG. 4, first, from every other charging hole # 1, # 3 from the machine side. After charging a predetermined amount (part) of coal, forming a mountain and depositing coal with a low pulverization rate directly under the adjacent charging hole, the remaining amount from other charging holes (Part) of charcoal is charged. By doing so, the charcoal charged from the other charging holes is charged (deposited) without colliding with the hard carburetor bottom refractory. Therefore, as compared with the conventional method in which the powdering rate reaches 20 mass% in the first charging, according to the present invention, the charging is first performed from every other charging hole and then from the remaining charging holes. In the method, the portion where the bulk density increases most can be reduced to half that of the conventional method.

  Thus, after finishing the charging from the first charging hole to be used selectively (every other) and the second charging from the other charging holes, 30 mass% in the furnace. Since about 70 mass% of the coal is deposited, pulverization at the time of charging the coal to be performed thereafter is suppressed. Therefore, the remaining coal may be charged from all the charging holes. Of course, the remaining cast charcoal may be continuously charged by alternately repeating the charging from the first charging hole and the charging from the next charging hole. However, it should be noted that when the charging is completed, if the peaks and valleys on the deposition upper surface in the carbonization chamber become too large, it may be difficult to level the deposition upper surface by the leveler.

  Here, if the amount of charcoal from the charging hole to be initially charged is less than 15 mass% of the amount of charging from the charging hole, the amount of coal flowing into the adjacent charging hole is small. Therefore, the pulverization of the charcoal charged from the adjacent charging hole cannot be sufficiently suppressed. On the other hand, when the amount of coal charged from the charging hole to be charged first exceeds 35 mass%, the mountain valley on the top surface of the deposit becomes too large, and the remaining coal coal is charged. Since it becomes difficult to level the upper surface, it is preferable that the charging amount in the first charging and the next charging is 15 mass% to 35 mass%.

  In FIG. 4, the case where there are four charging holes has been described. However, when the charging holes are odd numbers, for example, when the number is five, # 1, # 3, and # 5 are used first, and then # In addition to the case of using # 2 and # 4, first, charging is first performed from two charging holes (# 2, # 4) adjacent to the central charging hole (# 3), and then the two charging holes are used. It is preferable to perform charging from the charging holes (# 1, # 3, # 5) adjacent to. This is because it is possible to reduce the number of places at the bottom of the furnace directly below the charging hole with a high powdering rate.

<Example 1>
Actually, the charcoal chamber (H: 6700 mm, L: 15000 mm, W: 430 mm) was charged with 32 tons of total charcoal and carbonized under the same conditions to produce coke. As the carbonization chamber, a carbonization chamber having four charging holes (# 1 to # 4) was used. As an example of the invention, the following method of charging coal was carried out. That is, first, a part (10 mass%, 15 mass%, 25 mass%, 35 mass%, 40 mass%) of the total charging amount is supplied to each charging hole in equal amounts from the charging holes of # 1 and # 3. I was charged. Next, the remaining part (25 mass%) was supplied to each charging hole in an equal amount from the charging holes of # 2 and # 4, and charged. Next, all the remaining parts were supplied to the # 1 to # 4 charging holes by equal amounts and charged. On the other hand, as a conventional example, the same total charging amount of coal char was charged simultaneously in equal amounts from the # 1 to # 4 charging holes.

  And while measuring the load at the time of coke extrusion obtained after dry distillation, and the presence or absence of dry distillation failure, comprehensive judgment was performed from those results. Here, as the load at the time of coke extrusion, the current value of the extruder at the time of extruding coke is measured and evaluated by the average current value from the start to the end of the extrusion, and simultaneously from each charging hole corresponding to the conventional example The average current value at the time of charging was set to 100, and expressed as a ratio to this. Further, the presence or absence of defective carbonization was indicated as “good” as “good”, “minimum usable” as “Δ”, and defective as “poor”. Further, the overall judgment was expressed as “Excellent”, “Minimum usable”, “B”, and “B”, based on the results of coke extrusion load and dry distillation failure. The results are shown in Table 1 below.

  As is apparent from the results shown in Table 1, an example of the invention in which a part of the total charged amount was charged at the first time, the remaining part at the second time was charged, and the remaining at the third time was charged. It can be seen that coke can be produced without causing a dry distillation defect or an increase in extrusion load, as compared with the conventional example in which the entire charging amount is simultaneously charged from all charging holes. In addition, among the examples of the invention, it can be seen that an example in which the first charging is 15 mass% to 35 mass% can obtain better results than the other examples, and is a preferable range.

<Example 2>
Coke was produced in the same manner as in Example 1. At that time, the following method of charging coal was carried out as an example of the invention. That is, first, a part (25 mass%) of the total charging amount was supplied to each charging hole from the charging holes of # 1 and # 3 and charged. Next, the remaining part (10 mass%, 15 mass%, 25 mass%, 35 mass%, 40 mass%) is supplied to each charging hole by an equal amount from the charging holes of # 2 and # 4. did. Next, all the remaining parts were supplied to the # 1 to # 4 charging holes by equal amounts and charged. On the other hand, as a conventional example, the same total charging amount of coal char was charged simultaneously in equal amounts from the # 1 to # 4 charging holes.

  And similarly to Example 1, while measuring the load at the time of coke extrusion obtained after dry distillation, and the presence or absence of dry distillation failure, comprehensive judgment was performed from those results.

  As is apparent from the results shown in Table 2, an example of the invention in which a part of the total charged amount was charged at the first time, the remaining part at the second time was charged, and the remaining at the third time was charged. Compared with the conventional example in which the entire charging amount was charged simultaneously from all the charging holes, good results could be obtained. In addition, among the examples of the invention, it can be seen that an example in which the second charging is 15 mass% to 35 mass% can obtain better results than the other examples, and is a preferable range.

  According to the method for charging coal in a coke oven according to the present invention, even when coal is used as coal, coal can be suitably charged into the carbonization chamber of the coke oven. It can be applied to other coke ovens.

1 Simulated carbonization chamber 2 Sampling port 3 Charging hole 4 Cast charcoal hopper

Claims (3)

In the coke oven coal charging method in which only the coal is charged into the coke oven carbonization chamber through a plurality of charging holes provided in the ceiling of the carbonization chamber, first, every other charge is charged. Select a hole, and charge 15 mass % to 35 mass% of the total charging amount of coal, and then, from other charging holes that were not selected, further 15 mass% of the total charging amount of coal A coal charging method for a coke oven, wherein 35% by mass is charged, and then the remainder of the total amount of the coal is charged using all charging holes. When the coke oven has four charging holes, the first charcoal is charged from the first and third charging holes from the machine side or the coke side, and the next charcoal is charged. If the coke oven is provided with five charging holes, the first coal charging is performed from the machine side or the coke side side first, third and 5. The method for charging coal in a coke oven according to claim 1, wherein the charging is carried out in a fifth pattern, and the charging of the next coal is second and fourth or vice versa. In the first coal charging, the second coal charging, and the final coal charging, the amount of coal to be charged each time is charged in each charging hole. The method for charging coal in a coke oven according to claim 1 or 2 , wherein charging is performed by dividing into equal parts.

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