Preparation method of low-cost low-carbon sintered ore

Abstract

The invention relates to the technical field of sintering processes, in particular to a preparation method of low-cost low-carbon sinter, which comprises the following steps: establishing a perfect crude fuel ingredient database; establishing a cost performance evaluation calculation model; controlling the granularity of iron ore powder, solid fuel and flux; associating the cost performance model with batching software through a computer language to obtain crude fuel with high cost performance and sequencing the crude fuel; key parameters of sintering ore burdening are set; and a cloud computing service system is adopted, so that an optimal scheme for automatically optimizing ingredients is realized. The method has the advantages that the effects of reducing the batching cost and reducing the solid fuel consumption are obvious, and the annual benefit is more than 1,500-1,7500 million yuan; secondly, solid fuel is reduced, CO2 emission is reduced annually, and good social benefits are achieved; by means of the modern computer technology, ore blending software is wide in measuring and calculating range, short in period and easy to operate, decision basis is provided for manufacturing enterprises to reduce sinter cost and solid fuel consumption, and sinter quality is improved.

Description

Technical Field

[0001] The invention relates to the technical field of sintering processes, and in particular to a method for preparing low-cost low-carbon sintered ore. Background Art

[0002] With the implementation of the "carbon dual control" policy by the state and local governments, the steel industry has shifted from energy consumption dual control to carbon dual control. The traditional sintering ore production process has been greatly challenged in terms of carbon dual control. At the same time, affected by the adverse effects of real estate and other factors, the demand for steel in the downstream steel industry has dropped sharply, and the cost pressure of steel companies has become increasingly prominent, and the survival of companies has been severely tested. The sintering process is both a major carbon consumer and a key point in cost control. Therefore, the sintering process needs to adopt new technologies and processes to effectively achieve low-carbon sintering, and make due contributions to the realization of carbon peak and carbon neutrality. The sintering batching cost accounts for 67-71% of the sintering ore cost and 37-40% of the molten iron cost. Reducing the batching cost is the key to controlling the sintering ore cost, and it is also an inevitable trend and requirement for the sustainable development of long-process steel companies.

[0003] At present, sintering adopts micro-negative pressure ignition technology and manual experience in batching, water distribution and fire watching, which has achieved remarkable results in low gas consumption. The quality of sintered ore can basically meet the needs of blast furnaces. The flux uses 50% quicklime powder + 50% raw material flux (limestone powder, magnesite powder, dolomite lime powder), which meets the basicity and MgO content requirements in the sintered ore.

[0004] The existing technology has the following problems: first, manual batching is most affected by the batcher's experience, has great limitations, and there is still much room for improvement in cost control; second, the raw material flux ratio is too high, resulting in high sintering solid fuel, which does not meet the requirements of sintering low-carbon production. Summary of the invention

[0005] The purpose of the present invention is to provide a method for preparing low-cost low-carbon sintered ore to solve the problems existing in the above-mentioned background technology.

[0006] To achieve the above object, the present invention provides the following technical solution: a method for preparing low-cost low-carbon sintered ore, characterized in that:

[0007] S1: Establish a complete raw material and fuel ingredient database;

[0008] S2: Establish cost-effectiveness evaluation calculation models, including cost-effectiveness evaluation calculation models for iron ore powder, solid fuel, and flux;

[0009] S3: Control the particle size of iron ore powder, solid fuel and flux;

[0010] S4: The cost-effectiveness model is associated with the batching software through computer language, and N iteration cycles of optimization calculations are performed through the computer system to obtain raw fuels with high cost-effectiveness and sort them;

[0011] S5: Setting key parameters of sintering batching;

[0012] S6: The cloud computing service system is used to implement N-times iterative optimization calculations, thus realizing the automatic optimization of the optimal solution for the ingredients.

[0013] Furthermore, the calculation model for evaluating the cost performance of iron ore powder is:

[0014] P=TFe / (100+2R2*(MgO+CaO)-2*(SiO2+Al2O3)+5*(S+P+K2O+Na2O+Pb+ZnO+As

[0015] +Cl -1 )+C1*LOI+C2*((G-5)+(D-22)))*100…………………………………………①

[0016] M=Q / P…………………………………………………………………………②

[0017] Where: TFe, MgO, CaO, SiO2, Al2O3, S, P, K2O, Na2O, Pb, ZnO, As, Cl -1 , LOI represent the contents of total iron, magnesium oxide, calcium oxide, silicon dioxide, aluminum oxide, sulfur, phosphorus, potassium oxide, sodium oxide, lead, zinc oxide, arsenic, chloride ion and loss on ignition value in iron ore powder (%) respectively;

[0018] R2 is the basicity of sintered ore;

[0019] G and D represent the proportion of iron ore powder with particle size greater than 8 mm and 0.25-1 mm, respectively (%);

[0020] C1 and C2 represent the equivalent value of burning loss and particle size equivalent value of iron ore powder (%) respectively;

[0021] P is the comprehensive effective grade;

[0022] Q is the unit price on a dry basis;

[0023] M is the comprehensive effective grade unit value price.

[0024] Furthermore, the solid fuel cost performance evaluation calculation model is:

[0025] Q 效 =Q net.ad *(1-5%*(0.206*V ad / (0.206*V ad +0.023*M ad )))………………③

[0026] M1=Q 1干 / Q 效 ……………………………………………………………………④

[0027] Where: Q net.ad Represents the lower calorific value of solid fuel (kcal / kg);

[0028] Q net.ad 、V ad 、M ad Respectively represent the volatile matter and internal water content of solid fuel (%);

[0029] Q 效 It is the effective lower heating value;

[0030] Q 1干 is the dry basis price;

[0031] M1 is the effective unit calorific value price.

[0032] Furthermore, the calculation model for evaluating the cost performance of flux is:

[0033] UpR 效 =(UPr / (CaO-SiO2*R2+MgO)+72.77*UPg / 1000*RBR) / (1-LOI)…⑤

[0034] Where: UPr and UPg are the dry basis prices of flux and solid fuel respectively (yuan / t);

[0035] CaO, SiO2, and MgO are the contents of calcium oxide, silicon dioxide, and magnesium oxide in the flux, respectively (%);

[0036] R2 is the basicity of sintered ore;

[0037] RBR and LOI are the raw material rate and burning loss value of the flux (the raw material rate of the raw material flux is 100%, and the raw material rate of quicklime powder and light-burned dolomite powder is 8-15%).

[0038] Furthermore, the M and M 1、 UpR 效 The smaller the value, the higher the cost performance.

[0039] Furthermore, the database in S1 includes the chemical composition, particle size composition, and metallurgical properties of iron ore powder, the flux includes the chemical composition and particle size composition, and the solid fuel includes the chemical composition, calorific value, and particle size composition.

[0040] Furthermore, the particle sizes of the iron ore powder, solid fuel and flux in S3 are as follows: the proportion of iron ore powder with a particle size greater than 8 mm does not exceed 8%, the proportion of solid fuel particles with a particle size less than 3 mm after crushing is 75-85%, and the proportion of flux particles with a particle size less than 3 mm after crushing is greater than 90%.

[0041] Furthermore, the key chemical composition parameters of the sintered ore ingredients in the S5 are: TFe is 55.0-56.5%, SiO2 is 5.0-5.5%, MgO is 0-2.1%, Al2O3 is 1.0-2.1%, S is 0.025-0.032%, P is 0-0.090%, MgO / Al2O3 is 0.95-1.05%, Al2O3 / SiO2 is 0.10-0.40%, and R2 is 1.85-2.0%.

[0042] Compared with the prior art, the beneficial effects of the present invention are: first, reducing the batching cost (23 to 35 yuan / t ore) and reducing solid fuel (solid fuel is reduced by at least 5.60 kg / t ore), reducing the batching cost by 23 to 35 yuan / t ore, and creating annual benefits of more than 115 million to 175 million yuan; second, because the effect of reducing solid fuel is significant (5.60 kg / t ore), the standard coal is converted to 5.20 kgce / t ore, directly reducing CO2 emissions by 13.98 kg / t ore, and reducing CO2 emissions by 69,900 tons annually, which has good social benefits; third, with the help of modern computer technology, the ore blending software has a wide calculation range, a short cycle and simple operation, which provides a decision-making basis for production enterprises to reduce the cost of sintered ore and solid fuel consumption, reduce solid fuel consumption during sintering and improve the quality of sintered ore. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 It is a process flow chart of the preparation method of the present invention. DETAILED DESCRIPTION

[0044] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0045] The present invention provides a technical solution: a method for preparing low-cost low-carbon sintered ore, comprising:

[0046] The first step is to establish a complete raw material and fuel ingredient database; this is to provide reliable basic data for the establishment of a cost-effectiveness evaluation calculation model. The database contains the chemical composition, particle size composition, metallurgical properties, etc. of iron ore powder, the flux includes the chemical composition, particle size composition, etc., and the solid fuel includes the chemical composition, calorific value, particle size composition, etc.

[0047] The second step is to establish a cost-effectiveness evaluation calculation model, including an iron ore powder cost-effectiveness evaluation calculation model, a solid fuel cost-effectiveness evaluation calculation model, and a flux cost-effectiveness evaluation calculation model;

[0048] The calculation model for evaluating the cost performance of iron ore powder is:

[0049] P=TFe / (100+2R2*(MgO+CaO)-2*(SiO2+Al2O3)+5*(S+P+K2O+Na2O+Pb+ZnO+As

[0050] +Cl -1 )+C1*LOI+C2*((G-5)+(D-22)))*100…………………………………………①

[0051] M=Q / P…………………………………………………………………………②

[0052] Where: TFe, MgO, CaO, SiO2, Al2O3, S, P, K2O, Na2O, Pb, ZnO, As, Cl -1 , LOI represent the contents of total iron, magnesium oxide, calcium oxide, silicon dioxide, aluminum oxide, sulfur, phosphorus, potassium oxide, sodium oxide, lead, zinc oxide, arsenic, chloride ion and loss on ignition value in iron ore powder (%) respectively;

[0053] R2 is the basicity of sintered ore;

[0054] G and D represent the proportion of iron ore powder with particle size greater than 8 mm and 0.25-1 mm, respectively (%);

[0055] C1 and C2 represent the equivalent value of burning loss and particle size equivalent value of iron ore powder (%) respectively;

[0056] P is the comprehensive effective grade;

[0057] Q is the unit price on a dry basis;

[0058] M is the comprehensive effective grade unit value price.

[0059] The core of the calculation model for evaluating the cost-effectiveness of iron ore powder is to calculate the comprehensive effective grade P of the iron ore powder, and then divide the dry basis unit price Q by the comprehensive effective grade to obtain the comprehensive effective grade unit value price M. The smaller M is, the higher the cost-effectiveness.

[0060] The calculation model for evaluating the cost performance of solid fuel is:

[0061] Q 效 =Q net.ad *(1-5%*(0.206*V ad / (0.206*V ad +0.023*M ad )))………………③

[0062] M1=Q 1干 / Q 效 ……………………………………………………………………④

[0063] Where: Q net.ad Represents the lower calorific value of solid fuel (kcal / kg);

[0064] Q net.ad 、V ad 、M ad Respectively represent the volatile matter and internal water content of solid fuel (%);

[0065] Q 效 It is the effective lower heating value;

[0066] Q 1干 is the dry basis price;

[0067] M1 is the effective unit calorific value price.

[0068] Commonly used solid fuels for sintering include coke powder, anthracite, etc. The core of the solid fuel cost performance evaluation calculation model is the effective low calorific value Q 效 Then use the dry basis price Q 1干 Divide by the effective lower calorific value to get the effective unit calorific value price M1. The smaller M1 is, the higher the cost performance is.

[0069] The calculation model for evaluating the cost performance of flux is:

[0070] UpR 效 =(UPr / (CaO-SiO2*R2+MgO)+72.77*UPg / 1000*RBR) / (1-LOI)…⑤

[0071] Where: UPr and UPg are the dry basis prices of flux and solid fuel respectively (yuan / t);

[0072] CaO, SiO2, and MgO are the contents of calcium oxide, silicon dioxide, and magnesium oxide in the flux, respectively (%);

[0073] R2 is the basicity of sintered ore;

[0074] RBR and LOI are the raw material rate and burning loss value of the flux (the raw material rate of the raw material flux is 100%, and the raw material rate of quicklime powder and light-burned dolomite powder is 8-15%).

[0075] Commonly used fluxes for sintering include quicklime powder, light-burned dolomite powder, limestone powder, magnesite powder, etc. The core of the calculation model for evaluating the cost-effectiveness of fluxes is the effect of effective CaO and MgO content and the heat consumed by raw fluxes during the sintering process on the cost and quality of sintered ore. The calculation of the effective price of flux is 效 , U.P. 效 The smaller it is, the higher the cost performance.

[0076] The third step is to control the particle size of iron ore powder, solid fuel and flux; the proportion of iron ore powder with a particle size greater than 10mm shall not exceed 8%, the proportion of solid fuel particles less than 3mm after crushing shall be 75-85%, and the proportion of flux particles less than 3mm after crushing shall be greater than 90%. When the proportion of solid fuel particles less than 3mm after crushing is too low, the fuel will cause low sintering temperature and delayed terminal temperature during the sintering process, resulting in reduced sintered ore quality and increased solid fuel consumption; when the proportion less than 3mm is too high, the proportion of solid fuel particles less than 0.5mm after crushing will increase, and the exhaust will enter the flue gas at the beginning of sintering, resulting in increased solid fuel consumption. When the proportion of flux particles less than 3mm after crushing is low, the flux mixing will be uneven, affecting the uneven formation of liquid phase and reducing the activity of the flux, thereby affecting the material temperature and the "speckled face" of the sintering section, which will have a negative impact on the quality and consumption of sintered ore.

[0077] The fourth step is to write computer software using C++ programming language or other languages ​​to link the cost performance model with the batching software, and implement N iterative optimization operations through the computer system to obtain the raw fuels with the highest cost performance and sort them.

[0078] The fifth step is to set the key parameters of sintered ore batching; industrial experiments have proved that the following sintered ore batching parameter settings are the guarantee of quality and the important guarantee for low carbon and low cost. The key chemical composition parameters of sintered ore batching are: TFe is 55.0-56.5%, SiO2 is 5.0-5.5%, MgO is 0-2.1%, Al2O3 is 1.0-2.1%, S is 0.025-0.032%, P is 0-0.090%, MgO / Al2O3 is 0.95-1.05%, Al2O3 / SiO2 is 0.10-0.40%, and R2 is 1.85-2.0%.

[0079] The details are shown in the following table:

[0080] Sintered ore chemical composition design / %

[0081] TFe <![CDATA[SiO2]]> MgO <![CDATA[Al2O3]]> S P <![CDATA[MgO / Al2O3]]> <![CDATA[Al2O3 / SiO2]]> <![CDATA[R2]]> 55.0～56.5 5.0～5.5 ≤2.1 1.0～2.1 0.025～0.032 ≤0.090 0.95～1.05 0.10～0.40 1.85～2.0

[0082] The sixth step is to carry out sintering ore proportioning according to the requirements of the set values ​​of the sintering ore proportioning parameters. The cloud computing service system is used in the background to provide technical support for rapid calculations, realize N times of iterative cycle optimization calculations, and realize automatic optimization of the optimal proportioning solution.

[0083] Finally, industrial trials were carried out:

[0084] (1) Quantitative impact of clinker flux replacing raw material flux on solid fuel consumption

[0085] Industrial tests have shown that the quantitative relationship between the replacement of raw material flux with clinker flux in sintering ingredients and solid fuel consumption is: using 80% clinker flux (quicklime powder, light-burned dolomite powder) + 20% raw material flux (dolomite powder, magnesite powder, limestone powder) to replace 50% quicklime powder + 50% raw material flux (limestone powder, magnesite powder, dolomite powder), the solid fuel consumption is significantly reduced, and the solid fuel consumption is reduced from 52.3 kg / t to 1.5 kg / t. 矿 Reduced to 46.7 kg / t 矿 That is, reducing the use of 1 kg of raw material flux can reduce solid fuel consumption by 0.0676 kgce of standard coal. The fundamental reason is that raw material fluxes are carbonates (such as MgCO3, CaCO3, MgCO3.CaCO3) that consume heat to decompose during the sintering process, and in the decomposition process, the raw balls of the sintering material are destroyed, causing the permeability to deteriorate, affecting the strength of the sintered ore, and resulting in a decrease in the mineralization rate.

[0086] (2) The impact of optimizing the batching system on the sintering batching cost

[0087] Industrial tests have shown that, under the condition that the design of sintering ore batching parameters is consistent, the automatic batching output results of the optimal batching system and the manual batching output results, when the prices of raw materials, fuels and auxiliary materials are the same in the same period, the sintering batching cost is significantly reduced, and the batching cost is reduced by 23 to 35 yuan / t. 矿 The fundamental reason is that the optimal ore matching system can automatically select iron ore powder, solid fuel and flux with high cost performance, and perform N times of optimized iterative matching and output the results in a relatively short time; while the manual calculation speed is too slow, and it is impossible to calculate the cost performance one by one under many types of raw fuels and auxiliary materials, and it is impossible to perform iterative calculations. Even the number of iterative calculations realized in spreadsheets is very limited, which is not comparable to computer cloud service systems.

[0088] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for preparing low-cost low-carbon sintered ore, characterized in that: include S1: Establish a complete raw material and fuel ingredient database; S2: Establish cost-effectiveness evaluation calculation models, including cost-effectiveness evaluation calculation models for iron ore powder, solid fuel, and flux; S3: Control the particle size of iron ore powder, solid fuel and flux; S4: The cost-effectiveness model is associated with the batching software through computer language, and N iteration cycles of optimization calculations are performed through the computer system to obtain raw fuels with high cost-effectiveness and sort them; S5: Setting key parameters of sintering batching; S6: The cloud computing service system is used to implement N-times iterative optimization calculations, thus realizing the automatic optimization of the optimal solution for the ingredients.

2. The method for preparing a low-cost low-carbon sintered ore according to claim 1, characterized in that: The calculation model for evaluating the cost performance of iron ore powder is: P=TFe / (100+2R2*(MgO+CaO)-2*(SiO2+Al2O3)+5*(S+P+K2O+Na2O+Pb+ZnO+As +Cl -1 )+C1*LOI+C2*((G-5)+(D-22)))*100……………………………………① M=Q / P…………………………………………………………………………② Where: TFe, MgO, CaO, SiO2, Al2O3, S, P, K2O, Na2O, Pb, ZnO, As, Cl -1 , LOI represent the contents of total iron, magnesium oxide, calcium oxide, silicon dioxide, aluminum oxide, sulfur, phosphorus, potassium oxide, sodium oxide, lead, zinc oxide, arsenic, chloride ion and loss on ignition value in iron ore powder (%) respectively; R2 is the basicity of sintered ore; G and D represent the proportion of iron ore powder with particle size greater than 8 mm and 0.25-1 mm, respectively (%); C1 and C2 represent the equivalent value of burning loss and particle size equivalent value of iron ore powder (%) respectively; P is the comprehensive effective grade; Q is the unit price on a dry basis; M is the comprehensive effective grade unit value price.

3. The method for preparing a low-cost low-carbon sintered ore according to claim 1, characterized in that: The solid fuel cost performance evaluation calculation model is: Q 效 =Q net.ad *(1-5%*(0.206*V ad / (0.206*V ad +0.023*M ad )))………………③ M1=Q 1干 / Q 效 ………………………………………………………………④ Where: Q net.ad Represents the lower calorific value of solid fuel (kcal / kg); Q net.ad 、V ad 、M ad Respectively represent the volatile matter and internal water content of solid fuel (%); Q 效 It is the effective lower heating value; Q 1干 is the dry basis price; M1 is the effective unit calorific value price.

4. The method for preparing a low-cost low-carbon sintered ore according to claim 1, characterized in that: The calculation model for evaluating the cost performance of flux is: UPr 效 =(UPr / (CaO-SiO2*R2+MgO)+72.77*UPg / 1000*RBR) / (1-LOI)…⑤ Where: UPr and UPg are the dry basis prices of flux and solid fuel respectively (yuan / t); CaO, SiO2, and MgO are the contents of calcium oxide, silicon dioxide, and magnesium oxide in the flux, respectively (%); R2 is the basicity of sintered ore; RBR and LOI are the raw material rate and burning loss value of the flux (the raw material rate of the raw material flux is 100%, and the raw material rate of quicklime powder and light-burned dolomite powder is 8-15%).

5. A method for preparing low-cost low-carbon sintered ore according to claims 2-4, characterized in that: The M and M 1、 UpR 效 The smaller the value, the higher the cost performance.

6. The method for preparing a low-cost low-carbon sintered ore according to claim 1, characterized in that: The database in S1 includes the chemical composition, particle size composition, and metallurgical properties of iron ore powder, the flux includes the chemical composition and particle size composition, and the solid fuel includes the chemical composition, calorific value, and particle size composition.

7. The method for preparing a low-cost low-carbon sintered ore according to claim 1, characterized in that: The particle sizes of iron ore powder, solid fuel and flux in S3 are as follows: the proportion of iron ore powder with a particle size larger than 8 mm does not exceed 8%, the proportion of solid fuel with a particle size smaller than 3 mm after crushing is 75-85%, and the proportion of flux with a particle size smaller than 3 mm after crushing is greater than 90%.

8. The method for preparing a low-cost low-carbon sintered ore according to claim 1, characterized in that: The key chemical composition parameters of the sintered ore ingredients in the S5 are: TFe is 55.0-56.5%, SiO2 is 5.0-5.5%, MgO is 0-2.1%, Al2O3 is 1.0-2.1%, S is 0.025-0.032%, P is 0-0.090%, MgO / Al2O3 is 0.95-1.05%, Al2O3 / SiO2 is 0.10-0.40%, and R2 is 1.85-2.0%.

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