A method for calculating the theoretical slag quantity per ton of iron in an iron-making blast furnace

Abstract

The invention provides a method for calculating the theoretical slag amount per ton of iron in an ironmaking blast furnace, relates to the technical field of blast furnace ironmaking, and comprises the following steps: calculating materials required for pig iron, detecting component content, calculating the amount of elemental iron fed into the furnace per ton, obtaining elemental slag amount coefficients and calculating the theoretical slag amount per ton of iron; the invention uses a calculation method for the total material balance of slag amount, firstly calculates the amount of materials required for the blast furnace to produce pig iron, then detects the content of various components of all materials fed into the furnace, and then calculates the amount of iron fed into the furnace per ton of each element of the blast furnace raw material, and substitutes the slag amount coefficients of each element of the blast furnace obtained from a large database analysis into a slag amount formula to obtain the theoretical slag amount per ton of pig iron, thereby providing an important basis for blast furnace production, and the invention can quickly calculate the theoretical slag amount per ton of iron in the blast furnace, with higher efficiency, and is verified to accurately reflect the blast furnace slag amount control situation and the blast furnace condition fluctuation situation, which is of great significance to blast furnace production.

Description

Technical Field

[0001] The invention relates to the technical field of blast furnace ironmaking, and in particular to a method for calculating the theoretical slag amount per ton of iron in an ironmaking blast furnace. Background Art

[0002] Blast furnace slag is a by-product discharged from the blast furnace together with molten iron when smelting pig iron. During the blast furnace production process, the charge undergoes an oxidation-reduction reaction, and the gangue in the ore, the ash in the coke and other impurities that cannot enter the pig iron form a slag floating on the molten iron, which is mainly composed of minerals such as silicates, aluminates, and magnesian olivine. The main components of blast furnace slag are CaO, SiO2, Al2O3, and MgO. Depending on the grade of the ore, 0.30 to 1 ton of slag is discharged for every ton of iron smelted. The lower the ore grade, the greater the amount of slag discharged, and the amount of slag is higher. The amount of slag is a fundamental factor that directly affects the strengthening of the smelting process. A large amount of slag not only increases the air permeability resistance of the soft melting zone, but also increases the slag-to-coke ratio in the dripping zone, causing the retention of slag liquid in the coke pores to increase, increasing the risk of flooding, and becoming one of the main reasons restricting the strengthening of blast furnace smelting. As a by-product of blast furnace smelting, blast furnace slag cannot be obtained through actual measurement, but can only be obtained through theoretical calculation. The amount of slag per ton of iron in the blast furnace can accurately reflect the blast furnace smelting situation and the fluctuation of blast furnace conditions, which is of great significance to blast furnace production.

[0003] In the actual blast furnace production process, the amount of blast furnace slag cannot be obtained through actual measurement, and can only be calculated with the help of online related detection devices or fuzzy reasoning models to judge the slag discharge situation, but cannot judge the slag amount in the furnace. In the blast furnace production process, the slag in the furnace floats on the surface of the molten iron due to its low density and large volume. If the slag amount in the furnace cannot be judged, as the molten iron and slag are generated, the molten iron and slag occupy more and more space in the furnace, resulting in slag and iron accumulation in the furnace, slowing down the blast furnace unloading speed, and increasing the pressure difference in the furnace. In severe cases, it affects the smooth operation of the blast furnace. The existing technology mainly relies on online detection devices for Slag quantity calculation, under the condition of normal operation of production facilities and equipment, can provide reliable judgment basis for ensuring stable and smooth operation of blast furnace, and provide basis for subsequent slag flushing water adjustment. When an error occurs in a certain link of this set of slag quantity detection devices, it is easy to cause inaccurate measurement of blast furnace slag quantity. The blast furnace slag quantity is the gangue in the ore, the ash in the coke and other parts that cannot enter the pig iron after the oxidation-reduction reaction of the raw fuel entering the furnace, which occupy space in the furnace. This technology cannot calculate the blast furnace slag quantity. Therefore, the present invention proposes a method for calculating the theoretical slag quantity per ton of iron in an iron-making blast furnace to solve the problems existing in the prior art. Summary of the invention

[0004] In view of the above problems, the present invention proposes a method for calculating the theoretical slag amount per ton of iron in an iron-making blast furnace. The method for calculating the theoretical slag amount per ton of iron in an iron-making blast furnace utilizes a calculation method for the total material balance of slag amount. First, the amount of materials required for the blast furnace to produce pig iron is calculated, and then the content of various components of all materials entering the furnace is detected. Then, the amount of each element of the blast furnace raw material entering the furnace is calculated, and the slag amount coefficient of each element in the blast furnace obtained from the analysis of a large database is substituted into the slag amount formula to obtain the theoretical slag amount per ton of pig iron, thereby providing an important basis for blast furnace production.

[0005] To achieve the purpose of the present invention, the present invention is implemented by the following technical scheme: a method for calculating the theoretical slag amount per ton of iron in an iron-making blast furnace, comprising the following steps:

[0006] Step 1: Calculate the materials needed for pig iron

[0007] Measure the weight of all raw materials entering the blast furnace and calculate their dry weight C based on the moisture content i According to formula (1), the material consumption G required to produce 1 t of pig iron in a blast furnace is calculated. i :

[0008] G i =C i / (O+R)*1000 (1);

[0009] Step 2: Test the content of ingredients

[0010] Detect the content of various components of all materials entering the furnace nm stand-by;

[0011] Step 3: Calculate the amount of elemental iron entering the furnace

[0012] The amount of each element of iron per ton of raw material in the blast furnace is calculated according to the following formula (2):

[0013] MeO i =G i *E nm (2)

[0014] Step 4: Obtain element slag coefficient

[0015] The slag coefficient U of each element in the blast furnace is obtained based on the big data analysis of blast furnace element recovery and distribution statistics. i ;

[0016] Step 5: Calculate the theoretical slag volume per ton of iron

[0017] The theoretical slag volume M per ton of iron in a blast furnace is calculated according to the following formula (3):

[0018] M = ∑MeOi*Ui (3).

[0019] A further improvement is that in step 1, in formula (1): Gi Indicates the amount of materials used in the blast furnace to produce 1 ton of pig iron, in kg; C i It represents the dry weight of each raw material entering the blast furnace, in t; O represents the molten iron output, in t; R represents the sugar iron output, in t.

[0020] A further improvement is that in step 2, the various components include: TFe, S, SiO2, Al2O3, CaO, MgO, MnO, TiO2, V2O5 and alkali metals, and the content is expressed in mass percentage.

[0021] A further improvement is that in step three, in formula (2): MeOi represents the amount of each element per ton of iron fed into the blast furnace, in kg / t; Enm represents the mass percentage of TFe, S, SiO2, Al2O3, CaO, MgO, MnO, TiO2, V2O5 and alkali metals corresponding to each raw material fed into the blast furnace, in %.

[0022] A further improvement is that in step 3, when calculating the amount of each element of the blast furnace fuel fed into the furnace, the ash content is calculated first, and the calculation formula of the ash content is: weight of the residue after burning / sampling weight*100%=ash content.

[0023] A further improvement is that in step four, the big data of blast furnace element recovery and allocation statistics is specifically: a big database of monthly blast furnace element recovery and allocation statistics from 2017 to 2021.

[0024] A further improvement is that in step 4, the element slag coefficient U i is the proportion of blast furnace slag elements, and the slag coefficient of each element U i Specifically: TFe-0.23; S-81.00; SiO2-94.35; Al2O3-100; CaO-98.06; MgO-98.64; MnO-23.24; TiO2-75; V2O5-5; alkali metal -130.

[0025] A further improvement is that in step 5, in formula (3): M represents the theoretical slag amount per ton of iron in the blast furnace, in kg / t; U i Represents the blast furnace slag coefficient, in %.

[0026] The beneficial effects of the present invention are:

[0027] 1. The present invention uses a method for calculating the total material balance of slag volume. First, the amount of materials required for the blast furnace to produce pig iron is calculated. Then, the content of various components of all materials entering the furnace is detected. Then, the amount of each element of the blast furnace raw material per ton of iron entering the furnace is calculated. The slag volume coefficient of each element of the blast furnace obtained from the analysis of the big database is substituted into the slag volume formula to obtain the theoretical slag volume per ton of pig iron, which provides an important basis for blast furnace production.

[0028] 2. The present invention uses big data analysis to calculate the slag coefficient of each element entering the blast furnace, and calculates the theoretical slag volume per ton of iron in the blast furnace according to the formula "the amount of slag brought into the blast furnace by a ton of iron = the amount of each element entering the furnace * the slag coefficient of each element in the blast furnace slag". This method can quickly calculate the theoretical slag volume per ton of iron in the blast furnace, which is more efficient. It has been verified that it can accurately reflect the slag volume control situation and the fluctuation of the blast furnace condition, which is of great significance to blast furnace production. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a flow chart of the present invention. DETAILED DESCRIPTION

[0030] In order to deepen the understanding of the present invention, the present invention will be further described in detail below in conjunction with examples. The examples are only used to explain the present invention and do not constitute a limitation on the protection scope of the present invention.

[0031] according to Figure 1 As shown, this embodiment proposes a method for calculating the theoretical slag amount per ton of iron in an ironmaking blast furnace, comprising the following steps:

[0032] Step 1: Calculate the materials needed for pig iron

[0033] Measure the weight of all raw materials entering the blast furnace and calculate their dry weight C based on the moisture content i According to formula (1), the material consumption G required to produce 1 t of pig iron in a blast furnace is calculated. i :

[0034] G i =C i / (O+R)*1000 (1)

[0035] In formula (1): G i Indicates the amount of materials used in the blast furnace to produce 1 ton of pig iron, in kg; C i It represents the dry weight of each raw material fed into the blast furnace, in t; O represents the molten iron output, in t; R represents the sugar iron output, in t;

[0036] Step 2: Test the content of ingredients

[0037] Detect the content of various components of all materials entering the furnace nm The various ingredients include: TFe, S, SiO2, Al2O3, CaO, MgO, MnO, TiO2, V2O5 and alkali metals, and the content is expressed in mass percentage.

[0038] Step 3: Calculate the amount of elemental iron per ton of iron entering the furnace

[0039] The amount of each element of iron per ton of raw material in the blast furnace is calculated according to the following formula (2):

[0040] MeO i =G i *E nm (2)

[0041] In formula (2), MeOi represents the amount of each element per ton of iron fed into the blast furnace, in kg / t; Enm represents the mass percentage of TFe, S, SiO2, Al2O3, CaO, MgO, MnO, TiO2, V2O5 and alkali metals corresponding to each raw material fed into the blast furnace, in %. When calculating the amount of each element fed into the blast furnace fuel, the ash content is calculated first, and the calculation formula for the ash content is: weight of residue after burning / sampling weight*100%=ash content;

[0042] Step 4: Obtain element slag coefficient

[0043] Based on the big database of monthly blast furnace element recovery and distribution statistics from 2017 to 2021, the blast furnace slag coefficient U of each element is obtained. i , element slag coefficient U i is the proportion of blast furnace slag elements, and the slag coefficient of each element U i Specifically: TFe-0.23; S-81.00; SiO2-94.35; Al2O3-100; CaO-98.06; MgO-98.64; MnO-23.24; TiO2-75; V2O5-5; alkali metal-130;

[0044]

[0045] Step 5: Calculate the theoretical slag volume per ton of iron

[0046] The theoretical slag volume M per ton of iron in a blast furnace is calculated according to the following formula (3):

[0047] M=∑MeOi*Ui (3)

[0048] In formula (3): M represents the theoretical slag volume per ton of iron in the blast furnace, in kg / t; U i Represents the blast furnace slag coefficient, in %.

[0049] Verification Example 1

[0050] The theoretical slag volume per ton of iron is calculated by taking the blast furnace charging and output data in September 2020:

[0051]

[0052] According to statistics, the actual blast furnace slag per ton of iron is 347.41kg / t. The theoretical slag per ton of iron calculated by this method is basically equivalent to the actual slag per ton of iron produced by the blast furnace, with an error of only 0.35%.

[0053] Verification Example 2

[0054] The theoretical slag volume per ton of iron is calculated by taking the blast furnace charging and output data in June 2021:

[0055]

[0056] According to statistics, the actual blast furnace slag per ton of iron is 308.47kg / t. The theoretical slag per ton of iron calculated by this method is basically equivalent to the actual slag per ton of iron produced by the blast furnace, with an error of only 2%.

[0057] Verification Example 3

[0058] The theoretical slag volume per ton of iron is calculated by taking the blast furnace charging and output data in February 2021:

[0059]

[0060] According to statistics, the actual blast furnace slag per ton of iron is 313.01kg / t. The theoretical slag per ton of iron calculated by this method is basically equivalent to the actual slag per ton of iron produced by the blast furnace, with an error of only 1.68%;

[0061] Verification Example 4

[0062] The theoretical slag volume per ton of iron is calculated by taking the blast furnace charging and output data in January 2021:

[0063]

[0064] According to statistics, the actual amount of slag per ton of iron in a blast furnace is 334.77 kg / t. The theoretical amount of slag per ton of iron in a blast furnace calculated by this method is basically equivalent to the actual amount of slag per ton of iron in a blast furnace in production, with an error of only 1.17%.

[0065] The present invention uses a calculation method for the total material balance of slag volume, first calculates the amount of materials required for the blast furnace to produce pig iron, then detects the content of various components of all materials entering the furnace, and then calculates the amount of each element of the blast furnace raw material per ton of iron entering the furnace, and substitutes the slag volume coefficient of each element of the blast furnace obtained from the analysis of the big database into the slag volume formula to obtain the theoretical slag volume per ton of pig iron, providing an important basis for blast furnace production. In addition, the present invention uses big data analysis to calculate the slag volume coefficient of each element entering the blast furnace, and calculates the theoretical slag volume per ton of iron in the blast furnace according to the formula "ton of iron brought into the slag volume = each element entering the furnace volume * slag volume coefficient of each element in the blast furnace slag". Using this method, the theoretical slag volume per ton of iron in the blast furnace can be quickly calculated, which is more efficient. It has been verified that it can accurately reflect the slag volume control situation and the fluctuation of the blast furnace condition, which is of great significance to blast furnace production.

[0066] The above shows and describes the basic principles, main features and advantages of the present invention. It should be understood by those skilled in the art that the present invention is not limited to the above embodiments. The above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A method for calculating the theoretical slag amount per ton of iron in an iron-making blast furnace, characterized in that: The following steps are involved: Step 1: Calculate the materials required for pig iron; Measure the weight of all raw materials entering the blast furnace and calculate their dry weight C based on the moisture content i According to formula (1), the material consumption G required to produce 1 ton of pig iron in a blast furnace is calculated. i : G i =C i / (O+R)*1000(1); In formula (1): G i Indicates the amount of materials used in the blast furnace to produce 1 ton of pig iron, in kg; C i It represents the dry weight of each raw material fed into the blast furnace, in t; O represents the molten iron output, in t; R represents the sugar iron output, in t; Step 2: Detect ingredient content: Detect the content of various components of all materials entering the furnace nm stand-by; Step 3: Calculate the amount of elemental iron entering the furnace: The amount of each element of iron per ton of raw material in the blast furnace is calculated according to the following formula (2): MeO i =G i *E nm (2); In formula (2): MeO i Indicates the amount of each element of iron fed into the blast furnace, in kg / t; E nm Indicates the mass percentage of TFe, S, SiO2, Al2O3, CaO, MgO, MnO, TiO2, V2O5 and alkali metals corresponding to each raw material entering the furnace, in %; Step 4: Obtain element slag coefficient: Based on the big data analysis of blast furnace element recovery statistics, the slag coefficient U of each element in the blast furnace is obtained. i ; Element slag coefficient U i is the proportion of blast furnace slag elements, and the slag coefficient of each element U i Specifically: TFe-0.23; S-81.00; SiO2-94.35; Al2O3-100; CaO-98.06; MgO-98.64; MnO-23.24; TiO2-75; V2O5-5; alkali metal-130; Step 5: Calculate the theoretical slag volume per ton of iron: The theoretical slag volume M per ton of iron in a blast furnace is calculated according to the following formula (3): M=∑MeO i *U i (3); In formula (3): M represents the theoretical slag amount per ton of iron in the blast furnace, in kg / t.

2. The method for calculating the theoretical slag amount per ton of iron in an ironmaking blast furnace according to claim 1, characterized in that: In the step 3, when calculating the amount of each element of the blast furnace fuel fed into the furnace, the ash content is calculated first, and the calculation formula of the ash content is: weight of the residue after burning / sampling weight*100%=ash content.

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