Manufacturing method for coke

Abstract

To provide technology that enables frequent adjustment of a particle size of coke.SOLUTION: A manufacturing method for coke involves adding an inert material to a blended coal feedstock to manufacture coke. The manufacturing method for coke comprises: a step of measuring a coke particle size of the coke manufactured in a coke oven 30 by using a particle size measuring device 50 installed downstream of the coke oven 30; a step of determining a proportion of the inert material to be added to a blended coal feedstock based on the measured coke particle size; and a step of changing a proportion of the inert material to be added to the blended coal feedstock based on a determined proportion of the inert material.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a method for producing coke. [Background technology]

[0002] When coke is used as a reducing agent in a blast furnace, it is desirable for the coke particle size to be large in order to ensure ventilation in the blast furnace and to allow the reduction reaction to proceed sufficiently.

[0003] In general, the coke particle size can be adjusted by controlling the carbonization degree and thermoplasticity of coal and the operating rate of the coke oven.

[0004] However, the carbonization degree and thermoplasticity of coal are factors that determine the strength of coke, and therefore it is difficult to freely adjust them.In addition, the operating rate of coke ovens is determined based on the coke production plan, and therefore it is difficult to freely adjust them.

[0005] Another method for adjusting the coke particle size is known to be to control the coke particle size by adding inert materials such as coke breeze, petroleum coke, anthracite, etc. to the coal feedstock.

[0006] For example, Patent Document 1 discloses a method of adding fine coke to coal raw materials. For example, Patent Document 2 discloses a method of adding a low shrinkage carbonaceous material to the hearth of the carbonization chamber of a coke oven. For example, Patent Document 3 discloses a method of adding an additive that increases the coke particle size only to the coal charged on the wall side in the oven width direction of the coke oven. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Japanese Unexamined Patent Publication No. 62-190284 [Patent Document 2] JP 2014-91758 A [Patent Document 3] Japanese Patent Application Publication No. 10-273672 Summary of the Invention [Problem to be solved by the invention]

[0008] Patent Documents 1 to 3 disclose the amount of the inert substance to be added, but do not disclose a method for frequently adjusting the particle size of the coke.

[0009] An object of the present disclosure is to provide a method for producing coke that allows for frequent adjustment of coke particle size. [Means for solving the problem]

[0010] [1] A method for producing coke by adding an inert material to a blended coal raw material, comprising the steps of: measuring the coke particle size of the coke produced by the coke oven using a particle size measuring device installed downstream of the coke oven; determining a percentage of the inert material to be added to the blended coal feedstock based on the measured coke particle size; Varying the proportion of the inert material added to the blended coal feedstock based on the determined proportion of the inert material; A method for producing coke, comprising:

[0011] [2] The method for producing coke described in [1] above, wherein the step of determining the proportion of inert material includes changing the proportion of inert material from its current proportion if the measured coke particle size is not within a predetermined range.

[0012] [3] further comprising a step of recording a relationship between the changed inert matter percentage and the change in coke particle size; The method for producing coke described in [1] or [2] above, wherein the step of determining the proportion of inert material determines how much to change the proportion of inert material from its current proportion based on the relationship recorded in the past.

[0013] [4] A method for producing coke described in any one of [1] to [3] above, wherein the step of measuring the coke particle size is performed at least once an hour.

[0014] [5] A method for producing coke described in any one of [1] to [4] above, wherein a cooling device for cooling the coke produced by the coke oven is installed between the coke oven and the particle size measuring device.

[0015] [6] A method for producing coke described in any one of [1] to [5] above, wherein the inert substance is a carbonaceous material having a low shrinkage rate. Effect of the Invention

[0016] According to the coke manufacturing method of the present disclosure, the coke particle size can be adjusted frequently. [Brief description of the drawings]

[0017] [Figure 1] FIG. 1 is a diagram illustrating an example of a coke production system to which a coke production method according to an embodiment of the present disclosure is applied. [Diagram 2] FIG. 2 is a diagram illustrating a configuration example of a control device according to an embodiment of the present disclosure. [Diagram 3] FIG. 1 is a diagram showing an example of a change in coke particle size when the amount of coke powder added is changed. [Figure 4] FIG. 3 is a diagram in which the lower limit of the predetermined range of coke particle size is added. [Diagram 5] FIG. 1 is a diagram showing an example of the change in coke particle size when the proportion of inert material is changed. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings.

[0019] FIG. 1 is a diagram illustrating an example of a coke production system 1 to which a coke production method according to an embodiment of the present disclosure is applied.

[0020] The coke production system 1 includes a control device 10, a blending tank 20, a coke oven 30, a cooling device 40, and a particle size measuring device 50.

[0021] The controller 10 is a general-purpose computer such as a workstation, a personal computer, etc. Alternatively, the controller 10 may be a dedicated computer configured to function as the controller 10 for the coke production system 1.

[0022] The configuration and functions of the control device 10 will be described in detail later.

[0023] The blending tank 20 is a device that blends a plurality of brands of raw coal materials and adds an inert substance to the blended plurality of brands of raw coal materials.

[0024] The blending tank 20 includes a coal storage tank 21 and an inert material tank 22 .

[0025] The coal storage bin 21 stores a blended mixture of multiple brands of raw coal. Hereinafter, the blended mixture of multiple brands of raw coal may be referred to as a "blend of raw coal." In the blend of raw coal, multiple brands of raw coal are blended in a predetermined ratio so that the coke produced by the coke oven 30 has a target quality.

[0026] The coal storage bin 21 can discharge the blended coal raw materials onto the conveyor at a predetermined discharge amount. The discharge amount of the blended coal raw materials discharged from the coal storage bin 21 can be controlled by the control device 10.

[0027] The inert material tank 22 stores an inert material. The inert material is preferably a carbonaceous material with a low shrinkage rate. Here, the carbonaceous material with a low shrinkage rate is a carbonaceous material with a low shrinkage coefficient during carbonization. The inert material may be, for example, coke powder, petroleum coke, anthracite, or the like.

[0028] In general, the coke particle size can be increased by adding an inert material, which is a carbonaceous material with a low shrinkage rate, to a blended coal raw material. For example, inert materials such as coke powder have a different amount of shrinkage from coke produced from coal. Therefore, a difference in shrinkage occurs at the interface between them, and microcracks occur at the interface. This relieves stress, suppresses the generation and growth of crack nuclei, and increases the coke particle size.

[0029] The inert substance tank 22 can discharge the inert substance onto the conveyor at a predetermined discharge amount. The discharge amount of the inert substance discharged from the inert substance tank 22 can be controlled by the control device 10.

[0030] The control device 10 can change the ratio of the inert material added to the blended coal raw materials by controlling the amount of the inert material discharged from the inert material tank 22. The control device 10 can adjust the coke particle size of the coke produced by the coke oven 30 by changing the ratio of the inert material added to the blended coal raw materials.

[0031] The coke particle size is the average diameter of the coke particles. The average diameter may be calculated, for example, by an arithmetic mean or a harmonic mean. The coke particle size may be calculated by any method as long as it can be managed as an index.

[0032] The blended coal raw material to which the inert material has been added discharged from the blending tank 20 is transported to a coke oven 30 by a conveyor.

[0033] The coke oven 30 produces coke by carbonizing the blended coal raw material to which the inert material has been added, which is transported from the blending tank 20. The coke produced by the coke oven 30 is transported to the cooling device 40.

[0034] The cooling device 40 is installed downstream of the coke oven 30. The cooling device 40 cools the coke transported from the coke oven 30.

[0035] The coke produced by the coke oven 30 is at a high temperature and is therefore difficult to handle as is. By cooling the coke using the cooling device 40, the coke produced by the coke oven 30 becomes easier to handle.

[0036] The coke cooled by the cooling device 40 is transported to the next process, which is, for example, the production of pig iron in a blast furnace.

[0037] The particle size measuring device 50 is installed after the cooling device 40. The particle size measuring device 50 measures the coke particle size of the coke produced by the coke oven 30.

[0038] The particle size measuring device 50 may be, for example, a three-dimensional measuring device. When the particle size measuring device 50 is a three-dimensional measuring device, the particle size measuring device 50 measures the three-dimensional shape of the coke being conveyed by the conveyor and calculates the particle size of each coke particle. The particle size measuring device 50 calculates the average diameter by statistically processing the calculated particle sizes, thereby calculating the coke particle size.

[0039] Alternatively, the particle size measuring device 50 may be, for example, a sieve analyzer. When the particle size measuring device 50 is a sieve analyzer, the particle size measuring device 50 automatically samples the coke transported by the conveyor and performs a sieve analysis to calculate the coke particle size.

[0040] When the particle size measuring device 50 measures the coke particle size of the coke produced by the coke oven 30 , it transmits information on the measured coke particle size to the control device 10 .

[0041] The particle size measuring device 50 performs a process of measuring the coke particle size of the coke produced by the coke oven 30 at least once an hour.

[0042] Conventionally, coke was manually sampled on the conveyor downstream of the coke oven 30, and the sampled coke was subjected to sieve analysis to measure the coke particle size. In this case, the workload was high, so the coke particle size could be measured only a few times a day at most. Therefore, there was a problem that the process of measuring the coke particle size and changing the ratio of the inert material to be added could not be performed sequentially.

[0043] In contrast, the coke production system 1 according to this embodiment measures the coke particle size using the particle size measuring device 50, and can therefore sequentially measure the coke particle size at a high frequency, for example, at least once an hour.

[0044] The particle size distribution of the coke transported from the cooling device 40 to the next process changes due to particle breakage caused by collisions between particles. It is appropriate to manage the coke particle size based on the coke particle size of the coke immediately after it is produced in the coke oven 30. Therefore, it is preferable to install the particle size measuring device 50 in a position downstream of the cooling device 40 and close to the cooling device 40. For example, it is preferable to install the particle size measuring device 50 in a position downstream of the cooling device 40 where the conveyor transfer is about five times or less.

[0045] When the control device 10 acquires information on the coke particle size from the particle size measuring device 50, the control device 10 determines the ratio of the inert material to be added to the blended coal raw material based on the acquired coke particle size.

[0046] The control device 10 changes the ratio of the inert material to be added to the blended coal raw materials based on the determined ratio of the inert material. The control device 10 changes the ratio of the inert material to be added to the blended coal raw materials, for example, by controlling the amount of the inert material discharged from the inert material tank 22.

[0047] The ratio of the inert material to be added to the blended coal raw material may be automatically changed by the control device 10 as described above, or may be manually changed by an operator.

[0048] FIG. 2 is a diagram illustrating a schematic configuration example of the control device 10 according to an embodiment of the present disclosure.

[0049] The control device 10 includes a control unit 11, an input unit 12, an output unit 13, a storage unit 14, and a communication unit 15.

[0050] The control unit 11 includes at least one processor, at least one dedicated circuit, or a combination of these. The processor is a general-purpose processor such as a central processing unit (CPU) or a graphics processing unit (GPU), or a dedicated processor specialized for a specific process. The dedicated circuit is, for example, a field-programmable gate array (FPGA) or an application specific integrated circuit (ASIC).

[0051] The control unit 11 reads programs, data, etc. stored in the storage unit 14 and executes various functions.

[0052] The input unit 12 includes one or more input interfaces that detect user input and acquire input information based on a user operation. The input unit 12 includes, for example, physical keys, capacitive keys, a touch screen that is integrated with the display of the output unit 13, or a microphone that accepts voice input.

[0053] The output unit 13 includes one or more output interfaces that output information to notify a user. The output unit 13 includes, for example, a display that outputs information as an image, a speaker that outputs information as sound, etc. The display included in the output unit 13 may be, for example, an LCD (Liquid Crystal Display), a CRT (Cathode Ray Tube) display, etc.

[0054] The storage unit 14 is, for example, a flash memory, a hard disk, an optical memory, etc. A part of the storage unit 14 may be outside the control device 10. In this case, the part of the storage unit 14 may be a hard disk, a memory card, etc. connected to the control device 10 via an arbitrary interface.

[0055] The storage unit 14 stores programs for the control unit 11 to execute each function, data used by the programs, and the like.

[0056] The communication unit 15 includes at least one of a communication module corresponding to wired communication and a communication module corresponding to wireless communication. The control device 10 is capable of communicating with other devices via the communication unit 15.

[0057] Next, a process in which the control device 10 determines the ratio of the inert material to be added to the blended coal raw materials based on the coke particle size obtained from the particle size measuring device 50 will be described in more detail.

[0058] The control device 10 sets a predetermined range as the range of coke particle size, and determines the ratio of the inert material to be added to the blended coal raw materials so that the coke particle size falls within the predetermined range. For example, the control device 10 may determine the ratio of the inert material to be added to the blended coal raw materials so as to change the ratio of the inert material from the current ratio when the coke particle size is not within the predetermined range.

[0059] This allows the control device 10 to keep the coke grain size of the coke produced by the coke oven 30 within a range that does not deviate significantly from a predetermined range.

[0060] FIG. 3 is a diagram showing an example of a change in the particle size of coke when the amount of coke powder added as an inert material is changed.

[0061] In Fig. 3, the data points are the daily averages of the coke particle sizes measured at high frequency by the particle size measuring device 50. Graph 101 is a moving average of the daily average data of the coke particle sizes. Graph 102 is a moving average of the daily average data of the amount of coke fines added.

[0062] Since the particle size measuring device 50 can measure the coke particle size at high frequency, the control device 10 can easily obtain data such as that shown in FIG.

[0063] Fig. 4 is a diagram in which the lower limit of the predetermined range of coke particle size is added to Fig. 3. In Fig. 4, the lower limit of the predetermined range is a line indicated by reference numeral 103.

[0064] 4, the moving average of the coke particle size is below the lower limit of the predetermined range in regions 104 and 105. In such a case, when the control device 10 increases the proportion of the inert material added to the blended coal material, the coke particle size increases and falls within the predetermined range.

[0065] When the control device 10 changes the ratio of the inert material added to the blended coal raw materials, the control device 10 may record in the memory unit 14 the relationship between the changed ratio of the inert material and the change in the coke particle size.

[0066] FIG. 5 is a diagram showing an example of a change in coke particle size when the ratio of the inert material added to the blended coal material is changed.

[0067] 5, when the proportion of the inactive material is changed at date and time t1, the coke particle size changes by an amount of change 201. In this case, the control device 10 may record in the memory unit 14 the relationship between the proportion of the inactive material changed at date and time t1 and the change in the coke particle size.

[0068] When determining the ratio of the inert material to be added to the blended coal raw material, the control device 10 may determine how much to change the ratio of the inert material from the current ratio based on the relationship between the changed ratio of the inert material and the change in coke particle size recorded in the past. At this time, the control device 10 may determine the ratio of the inert material based on the relationship between the changed ratio of the inert material and the change in coke particle size recorded in the past, for example, by using a linear regression equation or by using case classification of conditions based on a decision tree structure.

[0069] The coke particle size does not depend only on the ratio of the inert material added to the blended coal raw materials. For example, the coke particle size also depends on the carbonization degree and thermoplasticity of the coal and the operating rate of the coke oven 30. For example, the coke particle size also depends on the components of the blended coal raw materials. Therefore, even if the ratio of the inert material added to the blended coal raw materials is constant, the coke particle size may change.

[0070] In such a case, the control device 10 may determine the proportion of the inert material to be added to the blended coal feedstock based on the relationship between the most recently changed proportion of the inert material and the change in coke particle size, thereby enabling the control device 10 to control the coke particle size in accordance with changes in operating conditions over time.

[0071] As described above, the method for producing coke according to the present embodiment includes a step of measuring the coke particle size of the coke produced by the coke oven 30 using the particle size measuring device 50 installed downstream of the coke oven 30, a step of determining the ratio of the inert material to be added to the blended coal raw materials based on the measured coke particle size, and a step of changing the ratio of the inert material to be added to the blended coal raw materials based on the determined ratio of the inert material. In this way, by measuring the coke particle size of the coke produced by the coke oven 30 using the particle size measuring device 50, the coke particle size can be measured frequently. In addition, the method for producing coke according to the present embodiment can determine the ratio of the inert material to be added to the blended coal raw materials based on the coke particle size measured frequently in this way, and can change the ratio of the inert material to be added to the blended coal raw materials based on the determined ratio of the inert material. Therefore, the method for producing coke according to the present embodiment can adjust the coke particle size frequently.

[0072] The present disclosure is not limited to the above-described embodiments. For example, multiple blocks shown in the block diagram may be integrated, or one block may be divided. Instead of executing multiple steps shown in the flowchart in chronological order as described, each step may be executed in parallel or in a different order depending on the processing capacity of the device executing each step, or as necessary. Other modifications are possible without departing from the spirit of the present disclosure.

[0073] For example, in the above-described embodiment, a plurality of brands of raw coal materials are blended and an inert substance is added to the blended raw coal materials in the blending tank 20. However, without being limited thereto, a plurality of brands of raw coal materials may be blended and an inert substance may be added to the blended raw coal materials in a raw material yard.

[0074] For example, in the above embodiment, the cooling device 40 is installed downstream of the coke oven 30, but the cooling device 40 does not necessarily have to be installed. [Explanation of symbols]

[0075] 1 Coke manufacturing system 10 Control device 11 Control section 12 Input section 13 Output section 14 Storage section 15 Communications Department 20 Blending tank 21 Coal storage tank 22 Inert substance tank 30 Coke oven 40 Cooling device 50 Particle size measuring device

Claims

1. A coke manufacturing method comprising adding an inert material to a blended coal raw material to manufacture coke, measuring the coke particle size of the coke produced by the coke oven using a particle size measuring device installed downstream of the coke oven; determining a percentage of the inert material to be added to the blended coal feedstock based on the measured coke particle size; Varying the proportion of the inert material added to the blended coal feedstock based on the determined proportion of the inert material; A method for producing coke, comprising:

2. 2. The method for producing coke as described in claim 1, wherein the step of determining the proportion of the inert material changes the proportion of the inert material from a current proportion when the measured coke particle size is not within a predetermined range.

3. recording a relationship between the changed inerts percentage and the change in coke particle size; The method for producing coke according to claim 2 , wherein the step of determining the proportion of the inert material determines how much to change the proportion of the inert material from a current proportion based on the relationship recorded in the past.

4. The method for producing coke according to claim 1 , wherein the step of measuring the coke particle size is performed at least once an hour.

5. The method for producing coke according to claim 1 , further comprising: a cooling device for cooling the coke produced by the coke oven, which is disposed between the coke oven and the particle size measuring device.

6. The method for producing coke according to claim 1 , wherein the inert material is a carbonaceous material having a low shrinkage rate.

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