A stacking method for mixed ore

Abstract

The present application relates to a stacking method for mixed ore, which belongs to the technical field of sintered ore preparation. The stacking method includes: formulating a stacking plan according to the preset component types and preset dosage relationships in the mixed ore; and according to the stacking plan, using a mixed BLOCK batching stacking method to make a stack to obtain a mixed ore. The stacking method uses a mixed BLOCK batching stacking method to make a stack, and by reducing the number of flux varieties in each BLOCK, the number of flux varieties in each BLOCK is limited to 1, and the types of fluxes in adjacent BLOCKs are different, which increases the number of BLOCKs and the number of flux stacking layers, improves the mixing degree of the batching and the uniformity of the flux distribution, and makes the stability rate of the SiO2 content and the CaO content in the mixed ore high, and obtains high-quality mixed ore, thereby effectively improving the stability rate of the basicity of the sintered ore.

Description

Technical Field

[0001] The present application relates to the technical field of sintered ore preparation, and in particular to a stacking method for mixed ore. Background Art

[0002] The quality of sintered ore directly affects ironmaking production. As one of the main indicators for evaluating the quality of sintered ore, the basicity of sintered ore plays an important role in the smooth operation of blast furnaces. Large-scale steel joint ventures all build mixed material yards to produce mixed ore to provide raw materials with stable composition and high cost performance for the sintering process, which is of great significance for the preparation of sintered ore.

[0003] At present, there is a problem of poor basicity stability in the preparation process of sintered ore. Summary of the invention

[0004] The present application provides a stacking method for mixed ore to solve the technical problem of poor basicity stability rate in the preparation process of sintered ore.

[0005] In a first aspect, the present application provides a stockpiling method for mixed ore, the stockpiling method comprising:

[0006] Formulate a stockpiling plan based on the preset component types and preset usage relationships in the mixed ore;

[0007] According to the stockpiling plan, a mixed BLOCK batching method is used to pile up and obtain a mixed ore;

[0008] Among them, in the mixing BLOCK ingredient stacking method, the number of types of flux contained in each BLOCK is 1, and the types of flux contained in adjacent BLOCKs are different.

[0009] Furthermore, in the mixing BLOCK ingredient stacking method, the number of BLOCKs is greater than 4.

[0010] Furthermore, in the mixing BLOCK ingredient stacking method, the number of BLOCKs is 6 to 8.

[0011] Furthermore, in the mixing BLOCK batching stacking method, the number of batching bins for each preset component type is greater than 1.

[0012] Furthermore, in the mixing BLOCK batching stacking method, the number of batching bins for each preset component type is 2 to 4.

[0013] Furthermore, in the mixing BLOCK batching and stacking method, a silo for recovering dust ash is provided.

[0014] Furthermore, the absolute value of the deviation between the actual value of the SiO2 content in the mixed ore and the planned value of the SiO2 content in the stockpiling plan is less than 0.15; the absolute value of the deviation between the actual value of the CaO content in the mixed ore and the planned value of the CaO content in the stockpiling plan is less than 0.25.

[0015] Furthermore, the preset component types include iron material, flux and fuel.

[0016] Furthermore, the types of flux include limestone, dolomite and premixed flux; the premixed flux includes sleeve kiln limestone undersize and digested slag.

[0017] Furthermore, the content of flux in the mixed ore is 9% to 10% by mass.

[0018] The above technical solution provided by the embodiment of the present application has the following advantages compared with the prior art:

[0019] An embodiment of the present application provides a stacking method for mixed ore, which adopts a mixed block batching stacking method to build a pile. By reducing the number of flux types in each BLOCK, the number of flux types in each BLOCK is limited to 1, and the types of flux contained in adjacent BLOCKs are different, thereby increasing the number of BLOCKs and the number of flux stacking layers, improving the mixing degree of the batching and the uniformity of the flux distribution, so that the stability rate of the SiO2 content and the CaO content in the mixed ore is high, and high-quality mixed ore is obtained, thereby effectively improving the stability rate of the basicity of the sintered ore. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0021] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0022] Figure 1 A schematic diagram of a process for stockpiling a mixed ore provided in an embodiment of the present application;

[0023] Figure 2 This is a schematic diagram of the optimization of the flux batching method in this application;

[0024] Figure 3 This is a diagram of mixing the limestone undersize and digestion slag in the sleeve kiln in this application;

[0025] Figure 4 This is a diagram of the proportions of the components in Example 1 of the present application. DETAILED DESCRIPTION

[0026] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0027] Unless otherwise specified, various raw materials, reagents, instruments and equipment used in this application can be purchased from the market or prepared by existing methods.

[0028] The quality of sintered ore directly affects ironmaking production. As one of the main indicators for evaluating the quality of sintered ore, the basicity of sintered ore plays an important role in the smooth operation of blast furnaces. Large-scale steel joint ventures all build mixed material yards to produce mixed ore to provide raw materials with stable composition and high cost performance for the sintering process, which is of great significance for the preparation of sintered ore.

[0029] At present, there is a problem of poor basicity stability in the preparation process of sintered ore. The raw material factor of mixed ore is the main limiting factor for improving the basicity stability of sintered ore. The existing technology on the pile of mixed ore includes:

[0030] Prior art 1 discloses a method for homogenizing ore and making piles and mixed ore (Chinese patent, CN201910424144.2). In the method for homogenizing ore and making piles of the patent, iron material, flux and fuel are pre-mixed to form a mixed ore with a fixed ratio. By storing them in a secondary material yard, the contact and mixing time of flux and fuel with ore powder is extended, thereby improving the distribution state of flux and fuel in the sintering of concentrate powder and improving the mineralization efficiency.

[0031] Prior art 2 discloses a method for improving the stability of mixed ore components (Chinese patent, CN201811315674.5). In the mixed ore pile making method of this patent, under the condition of ensuring that the quality indicators of the mixed ore meet the sintering requirements, the proportion of iron ore species with poor particle size composition and large composition fluctuations can be increased, thereby achieving the purpose of improving the stability rate of the mixed ore components, and at the same time, the stability rate of the sintered ore component indicators can be effectively improved.

[0032] The technical solution provided by the embodiment of the present invention is to solve the above technical problems, and the overall idea is as follows:

[0033] like Figure 1 As shown, an embodiment of the present application provides a stacking method for mixed ore, the stacking method comprising:

[0034] Formulate a stockpiling plan based on the preset component types and preset usage relationships in the mixed ore;

[0035] According to the stockpiling plan, a mixed BLOCK batching method is used to pile up and obtain a mixed ore;

[0036] Among them, in the mixing BLOCK ingredient stacking method, the number of types of flux contained in each BLOCK is 1, and the types of flux contained in adjacent BLOCKs are different.

[0037] An embodiment of the present application provides a stacking method for mixed ore, which adopts a mixed block batching stacking method to build a pile. By reducing the number of flux types in each BLOCK, the number of flux types in each BLOCK is limited to 1, and the types of flux contained in adjacent BLOCKs are different, thereby increasing the number of BLOCKs and the number of flux stacking layers, improving the mixing degree of the batching and the uniformity of the flux distribution, so that the stability rate of the SiO2 content and the CaO content in the mixed ore is high, and high-quality mixed ore is obtained, thereby effectively improving the stability rate of the basicity of the sintered ore.

[0038] In this application, the core content of the technical solution of this application is: in the mixing block batching stacking method, the number of types of flux contained in each block is 1, and the types of flux contained in adjacent blocks are different. For example, Figure 2 As shown, when limestone and dolomite are selected as flux, the limestone and dolomite are dispersed in different BLOCKs to ensure that each BLOCK is equipped with a single type of flux. However, the preset component types and preset dosage relationships in the mixed ore can be carried out according to the actual sintering ore preparation process requirements, and this application document will not repeat them.

[0039] In this application, in some specific embodiments, the relationship between the preset component types and preset dosages in the mixed ore may include: according to the actual sintered ore preparation process requirements, the total number of ore types involved in the batching, the type of flux, the type of fuel, and the weight ratio of each ore type, the weight ratio of the flux, the weight ratio of the fuel, etc. can be determined under the premise of a certain total amount of stockpiling. The stockpiling plan can be formulated according to existing conventional processes, or it can be formulated according to the relevant contents of the stockpiling plan disclosed in the prior art II, which discloses a method for improving the stability of mixed ore components (Chinese patent, CN 201811315674.5).

[0040] As an implementation method of the embodiment of the present application, in the mixing BLOCK ingredient stacking method, the number of BLOCKs is greater than 4.

[0041] In the process of preparing mixed ore, a detailed list of mixed ore ingredients will be formulated from the perspectives of resource balance, ingredient control, and cost calculation. Generally speaking, each pile of mixed ore will be divided into four to seven steps for stacking, and each step is an independent unit, called BLOCK. At present, the prior art generally adopts the four-BLOCK method to prepare mixed ore, but in this application, when the mixed ore is stacked, the flux is dispersed in the mixed ore as a raw material participating in the batching according to the proportion of each BLOCK. Increasing the number of BLOCKs is to increase the number of independent units, which improves the mixing degree of the ingredients and the uniformity of the flux distribution, so that the stability rate of the SiO2 content and the CaO content in the mixed ore is high, and high-quality mixed ore is obtained, thereby effectively improving the stability rate of the basicity of the sintered ore.

[0042] In this application, the number of BLOCKs can be adjusted according to actual conditions and is not fixed.

[0043] As an implementation method of the embodiment of the present application, in the mixing BLOCK ingredient stacking method, the number of BLOCKs is 6 to 8.

[0044] In the present application, in some specific embodiments, the number of BLOCKs may be 6, 7 or 8.

[0045] As an implementation method of an embodiment of the present application, in the mixing BLOCK ingredient stacking method, the number of ingredient bins for each preset component type is greater than 1.

[0046] In the present application, a silo is set for each variety in the prior art to increase the number of silos. For example, each variety can be changed to use 3 silos for batching at the same time. When the total material amount remains unchanged, the material amount fluctuation can be avoided and the stability of the mixed ore can be further improved.

[0047] As an implementation of an embodiment of the present application, in the mixing BLOCK ingredient stacking method, the number of ingredient bins for each preset component type is 2 to 4.

[0048] In the present application, in some specific embodiments, the number of batching bins for each preset component type may be 2, 3 or 4.

[0049] As an implementation method of an embodiment of the present application, in the mixing BLOCK ingredient stacking method, a silo for recovering dust ash is provided.

[0050] In the present application, a long-term silo dedicated to recovering dust is provided, which is coordinated with other silos to prepare materials at the same time, so that it is always in a material pulling state to avoid fluctuations in material quantity caused by dust accumulation.

[0051] As an implementation example of the present application, the absolute value of the deviation between the actual value of the SiO2 content in the mixed ore and the planned value of the SiO2 content in the stockpiling plan is less than 0.15; the absolute value of the deviation between the actual value of the CaO content in the mixed ore and the planned value of the CaO content in the stockpiling plan is less than 0.25.

[0052] In the present application, the absolute value of the deviation between the actual value of the SiO2 content in the mixed ore and the planned value of the SiO2 content in the stockpiling plan is less than 0.15; the absolute value of the deviation between the actual value of the CaO content in the mixed ore and the planned value of the CaO content in the stockpiling plan is less than 0.25, and the deviations between the actual values ​​and the planned values ​​of the SiO2 and CaO contents in the mixed ore are both within a very small range, which meets the requirements of quality control, and the quality of the mixed ore is significantly improved, creating better raw material conditions for the sintering process, thereby effectively improving the basicity stability rate of the sintered ore.

[0053] As an implementation of an embodiment of the present application, the preset component types include iron material, flux and fuel.

[0054] In this application, the preset component types can be selected according to the actual process requirements and the technical contents disclosed in the prior art such as the prior art 1 which discloses a method for homogenizing ore and mixing ore (Chinese patent, CN201910424144.2).

[0055] As an implementation method of an embodiment of the present application, the types of flux include limestone, dolomite and premixed flux; the premixed flux includes sleeve kiln limestone undersize and digested slag.

[0056] In the present application, in some specific embodiments, there are four types of fluxes involved in the mixing and batching of ore: sintered limestone, sintered dolomite, sleeve kiln high-calcium limestone screenings, and digestion slag. Among them, digestion slag is a by-product of the digestion line, and its CaO content is as high as 60%, and its utilization value is high, but it contains some large-particle flux and is not suitable for input into the flux bin of the sintering batching room. Therefore, the digestion slag is arranged to enter the flux preparation system alone. Due to its good fluidity, the material flow cannot be controlled, overflows from the belt conveyor, and damages the on-site equipment. Therefore, in the present application, the digestion slag is arranged to be mixed with the sleeve kiln high-calcium limestone screenings with a larger particle size to obtain a premixed flux, such as Figure 3 As shown, the premixed flux is regarded as a single type of flux for stockpiling, thereby effectively solving the problem of the allocation of digested ash.

[0057] As an implementation method of the embodiment of the present application, the content of flux in the mixed ore is 9% to 10% by mass.

[0058] At present, in various steel enterprises, some raw material plants do not have independent flux crushing equipment, and no flux is added to the mixed ore; in some mixed ore production processes, the flux ratio is relatively small, generally rarely exceeding 5%. However, in the present invention, the flux ratio can be increased to 9%-10% in actual production, achieving high-ratio flux mixing and ore blending.

[0059] The present application will be further described below in conjunction with specific embodiments. It should be understood that these embodiments are intended only to illustrate the present application and are not intended to limit the scope of the present application. The experimental methods for which specific conditions are not specified in the following examples are usually measured according to national standards. If there is no corresponding national standard, then the conditions recommended by the manufacturer are followed.

[0060] Example 1

[0061] This example provides a stacking method for mixed ore, the stacking method comprising:

[0062] Formulate a stockpiling plan based on the preset component types and preset usage relationships in the mixed ore;

[0063] According to the stockpiling plan, a mixed BLOCK batching method is used to pile up and obtain a mixed ore;

[0064] Wherein, in the mixing BLOCK batching stacking method, the number of types of flux contained in each BLOCK is 1, and the types of flux contained in adjacent BLOCKs are different;

[0065] There are four types of fluxes involved in mixing and blending the ore: sintered limestone, sintered dolomite, sleeve kiln high calcium limestone screenings, and digested slag;

[0066] Each BLOCK is equipped with one type of flux. The mixed ore pile weight remains unchanged at 260,000 tons. The flux types are arranged at intervals. The number of BLOCKs is 7. The specific configuration is as follows: Figure 4 As shown in the figure, each variety is batched in three silos instead of one silo. At the same time, a silo used for long-term use and specially for recovering dust is fixed, and it is batched in conjunction with other silos to keep it in a pulling state all the time, avoiding fluctuations in material quantity caused by dust accumulation.

[0067] In this example, the absolute value of the deviation between the actual value of the SiO2 content in the mixed ore and the planned value of the SiO2 content in the stockpile plan is less than 0.15; the absolute value of the deviation between the actual value of the CaO content in the mixed ore and the planned value of the CaO content in the stockpile plan is less than 0.25. In terms of mass fraction, the content of flux in the mixed ore is 9% to 10%.

[0068] Comparative Example 1

[0069] On the basis of Example 1, this example provides a stacking method for mixed ore, and the only difference from Example 1 is that the number of BLOCKs is 4, and the raw material proportions (including flux) in the fifth BLOCK, the sixth BLOCK and the seventh BLOCK in Example 1 are evenly redistributed to the first BLOCK to the fourth BLOCK, and the remaining steps and parameters are the same.

[0070] In this example, the absolute value of the deviation between the actual value of the SiO2 content in the mixed ore and the planned value of the SiO2 content in the stockpiling plan is greater than 0.15; the absolute value of the deviation between the actual value of the CaO content in the mixed ore and the planned value of the CaO content in the stockpiling plan is greater than 0.30, which does not meet the requirements for mixed ore quality control.

[0071] Various embodiments of the present application may be presented in the form of a range; it should be understood that the description in the form of a range is only for convenience and brevity, and should not be understood as a rigid limitation on the scope of the present application; therefore, the range description should be considered to have specifically disclosed all possible sub-ranges and single numerical values ​​within the range. For example, the range description from 1 to 6 should be considered to have specifically disclosed sub-ranges, such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6, etc., as well as single numbers within the range, such as 1, 2, 3, 4, 5 and 6, which apply regardless of the range. In addition, whenever a numerical range is indicated herein, it is meant to include any cited number (fractional or integer) within the indicated range.

[0072] In the present application, in the absence of any contrary description, the directional words used, such as "upper" and "lower", are specifically the directions of the drawings in the accompanying drawings. In addition, in the description of the present specification, the terms "including", "comprising", etc. refer to "including but not limited to". In this article, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply that there is any such actual relationship or order between these entities or operations. In this article, "and / or" describes the association relationship of the associated objects, indicating that there may be three relationships, for example, A and / or B, which can represent: A exists alone, A and B exist at the same time, and B exists alone. Wherein A, B can be singular or plural. In this article, "at least one" refers to one or more, and "plural" refers to two or more. "At least one", "at least one of the following" or similar expressions refer to any combination of these items, including any combination of singular or plural items. For example, "at least one of a, b, or c", or "at least one of a, b and c", can both mean: a, b, c, ab (i.e. a and b), ac, bc or abc, where a, b, c can be single or plural, respectively.

[0073] The above description is only a specific implementation of the present application, so that those skilled in the art can understand or implement the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest range consistent with the principles and novel features applied for herein.

Claims

1. A method for stockpiling mixed ore, characterized in that: The stacking method comprises: Formulate a stockpiling plan based on the preset component types and preset usage relationships in the mixed ore; According to the stockpiling plan, a mixed BLOCK batching method is used to pile up and obtain a mixed ore; Wherein, in the mixing BLOCK batching stacking method, the number of types of flux contained in each BLOCK is 1, and the types of flux contained in adjacent BLOCKs are different; The types of flux include limestone, dolomite and premixed flux; the premixed flux includes sleeve kiln limestone undersize and digestion slag; The content of flux in the mixed ore is 9% to 10% by mass fraction; In the mixing BLOCK ingredient stacking method, the number of BLOCKs is greater than 4.

2. The method for stockpiling mixed ore according to claim 1, characterized in that: In the mixing BLOCK ingredient stacking method, the number of BLOCKs is 6 to 8.

3. The stockpiling method of mixed ore according to claim 1, characterized in that: In the mixing BLOCK batching stacking method, the number of batching bins for each preset component type is greater than 1.

4. The method for stockpiling mixed ore according to claim 1, characterized in that: In the mixing BLOCK batching stacking method, the number of batching bins for each preset component type is 2 to 4.

5. The stockpiling method of mixed ore according to claim 1, characterized in that: In the mixing BLOCK batching and stacking method, a silo for recovering dust is provided.

6. The stockpiling method of mixed ore according to claim 1, characterized in that: The absolute value of the deviation between the actual value of the SiO2 content in the mixed ore and the planned value of the SiO2 content in the stockpiling plan is less than 0.15; the absolute value of the deviation between the actual value of the CaO content in the mixed ore and the planned value of the CaO content in the stockpiling plan is less than 0.

25.

7. The stockpiling method of mixed ore according to claim 1, characterized in that: The preset component types include iron material, flux and fuel.

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