Blast furnace energy consumption monitoring and hydrogen-rich smelting prediction method based on rist operating line

Abstract

The application discloses a blast furnace energy consumption monitoring and hydrogen-rich smelting prediction method based on a Rist operation line, and the monitoring method comprises the following steps: introducing blast furnace production data to calculate hydrogen utilization and hydrogen reduction degree, and determining a blast furnace Rist operation line with hydrogen participation to determine direct reduction degree; and monitoring blast furnace energy consumption according to the direct reduction degree and the hydrogen reduction degree to determine each energy consumption data. The prediction method is based on carbon-oxygen balance before tuyere, material balance and heat balance constraint conditions of each region, and the current fuel ratio and the direct reduction degree are continuously iterated through a cyclic iteration method to determine B point final coordinates and a final fuel ratio, so that the final blast furnace Rist operation line with hydrogen participation is determined; and each energy consumption index of the blast furnace under different hydrogen-rich smelting conditions is predicted according to the final blast furnace Rist operation line with hydrogen participation. The application not only improves the blast furnace energy consumption monitoring effect, but also can predict each energy consumption data of the blast furnace under different hydrogen-rich smelting conditions.

Description

Technical Field

[0001] This invention relates to the field of blast furnace ironmaking, and in particular to a method for monitoring blast furnace energy consumption and predicting hydrogen-rich smelting based on the Rist operating line. Background Technology

[0002] The modern steel industry, as a pillar of the national economy, is also a high-energy-consuming and high-emission industry. Blast furnaces, as one of the most important pieces of equipment in steel smelting, account for over 87% of the total CO2 emissions and about 70% of the total energy consumption in the steel industry, thus bearing a significant responsibility for energy conservation and emission reduction in steel production. With the introduction of the "dual carbon" target in recent years, hydrogen-rich blast furnace smelting technology has gradually received widespread attention and has been further developed and promoted. However, due to the complexity of the reactions within the blast furnace, it is considered "the most complex metallurgical reactor." Although the blast furnace control room currently has automated equipment such as material gauge lines, furnace top material level imaging, and tuyere imaging to assist in adjusting the upper and lower parts of the blast furnace to stabilize production, key energy consumption indicators such as changes in the degree of reduction within the blast furnace, C consumption per ton of iron, gas generation process, energy consumption, and CO2 emissions cannot be directly obtained. These indicators involve complex material and heat balance calculations within the blast furnace, and the calculation process is cumbersome. To simplify the calculation process, the direct degree of reduction r is usually given. d Hydrogen utilization rate η H2 While calculations based on empirical constants are often used, the increasing complexity of blast furnace smelting conditions, driven by new technologies such as oxygen-enriched pulverized coal injection, hydrogen-rich material injection, and the use of iron coke, makes calculations based on empirical constants unreasonable. Furthermore, the H2O content in the top gas of the blast furnace, especially the water involved in reduction, cannot be directly monitored or obtained in actual blast furnace production. This makes it impossible to accurately predict the ore reduction process and gas generation process within the blast furnace, resulting in poor blast furnace energy consumption monitoring. In addition, different hydrogen-enriched smelting processes need to be predicted and evaluated before implementation. Therefore, a method for monitoring and predicting the energy consumption of hydrogen-enriched blast furnaces is urgently needed. Summary of the Invention

[0003] The purpose of this invention is to provide a method for monitoring blast furnace energy consumption and predicting hydrogen-rich smelting based on the Rist operating line. It mainly considers the influence of hydrogen and determines the Rist operating line of the blast furnace with hydrogen participation. This solves the problem of not being able to accurately predict the ore reduction and gas generation process in the production blast furnace, improves the monitoring effect of blast furnace energy consumption, and enables the prediction and evaluation of different hydrogen-rich smelting processes.

[0004] The most crucial aspects of the blast furnace energy consumption monitoring method and hydrogen-rich blast furnace prediction method provided by this invention lie in determining the direct reduction degree and the hydrogen reduction degree. Furthermore, predicting the fuel ratio in the blast furnace is also important. To obtain blast furnace energy consumption indicators, the fuel ratio, direct reduction degree, and hydrogen reduction degree are indispensable. In the blast furnace energy consumption monitoring method, the fuel ratio is known, while the hydrogen-rich blast furnace prediction method requires additional prediction of the fuel ratio.

[0005] In the attached diagram, the horizontal axis of the blast furnace Rist with hydrogen participation is [n(O)+n(H2)] / [n(C)+n(H2)], which represents the number of moles of oxygen and hydrogen combined per mole of (C+H2), reflecting the destination of oxygen and hydrogen. The vertical axis is [n(O)+n(H2)] / n(Fe), which represents the source of oxygen and hydrogen per mole of Fe during smelting. Point A represents the oxidation degree of the iron ore entering the furnace and the oxidation degree of carbon in the top gas. Point B is the theoretical dividing point between direct reduction and indirect reduction. Point E is the starting point for the generation of CO and H2 before the tuyeres. Point W is the limit point for indirect reduction of iron. Point Z is the key point for furnace efficiency. Point G is a point on the straight line with an horizontal axis of 1, and the furnace efficiency at point G is 0.

[0006] To achieve the above objectives, the present invention provides the following solution:

[0007] A method for monitoring blast furnace energy consumption based on the Rist operating line includes:

[0008] Import blast furnace production data and calculate hydrogen utilization rate based on the blast furnace production data and hydrogen balance; the blast furnace production data includes blast furnace raw material conditions, product parameters, and injection parameters;

[0009] The degree of hydrogen reduction is calculated based on the hydrogen utilization rate.

[0010] Based on the blast furnace production data, determine the coordinates of point A and point E on the blast furnace Rist operation line where hydrogen is involved.

[0011] The Rist operating line for blast furnaces with hydrogen involvement is determined based on the coordinates of point A and point E.

[0012] The degree of direct reduction is determined based on the hydrogen-involved blast furnace Rist operating line.

[0013] Blast furnace energy consumption is monitored based on the direct reduction degree and the hydrogen reduction degree to determine various energy consumption data. The energy consumption data includes material balance, reduction degree distribution, gas generation process, theoretical combustion temperature in the tuyeres area, thermal balance in the high-temperature zone, thermal balance in the low-temperature zone, overall thermal balance of the blast furnace, furnace working efficiency, C consumption per ton of iron and CO2 emissions, theoretical carbon consumption per ton of iron and carbon saving potential.

[0014] Optionally, the utilization rate of hydrogen is calculated based on the blast furnace production data and hydrogen balance, specifically including:

[0015] Using formula Calculate the utilization rate of the hydrogen;

[0016] Where, η H2 ΣvH2O represents the hydrogen utilization rate, vH2O represents the amount of water generated from hydrogen reduction, and ΣvH2 represents the total volume of hydrogen entering the furnace, which includes hydrogen from the cracking of raw materials and hot air, as well as the equivalent hydrogen injected into the hydrogen-rich medium; v g This refers to the volume of gas at the top of a blast furnace for smelting pig iron. This represents the volume percentage of hydrogen in the top gas of a blast furnace used for smelting pig iron. This represents the volume percentage of methane in the top gas of a blast furnace used for smelting pig iron. The volume percentage of CO2 in the top gas of a pig iron blast furnace in a smelting unit. C represents the volume percentage of CO in the top gas of a pig iron blast furnace in a smelting unit. 总 This refers to the total amount of carbon fed into the furnace, including carbon in coke and pulverized coal; C 渗 C represents the amount of carburization in the molten iron. 尘 This refers to the amount of carbon carried out by furnace dust.

[0017] Optionally, the reducing power of the hydrogen for:

[0018]

[0019] Wherein, [Fe] represents the mass fraction of iron in the molten iron.

[0020] A method for predicting hydrogen-rich smelting based on the Rist operating line determines the final Rist operating line of the blast furnace with hydrogen participation through a cyclic iterative method under different hydrogen-rich smelting conditions, including:

[0021] Import blast furnace raw material conditions, product parameters, injection parameters, and furnace working efficiency η shaft The blast furnace raw material and fuel conditions include iron ore type, furnace charge structure, fuel ratio, raw material and fuel chemical composition, and blast parameters; the product parameters include molten iron composition, slag composition, furnace dust composition, and furnace dust quantity; the injection parameters include injection medium type, injection volume, injection temperature, injection location, and hydrogen utilization rate; the blast parameters include blast humidity, blast temperature, oxygen enrichment rate, and oxygen purity.

[0022] Based on the blast furnace raw material conditions, the product parameters, and the furnace working efficiency η shaft The injection parameters determine the coordinates of point G and point W in the hydrogen-involved blast furnace Rist operating line.

[0023] Based on the principle of triangle similarity, and according to the furnace working efficiency η shaft The coordinates of point Z are determined by the coordinates of point W and the coordinates of point G.

[0024] The direct reduction degree and the current fuel ratio are assigned values. Based on the carbon-oxygen balance in front of the tuyere and the material and heat balance constraints of each region, the direct reduction degree and the current fuel ratio are continuously iterated using a cyclic iterative method to determine the final coordinates and final fuel ratio of point B. The heat balance constraints of each region include the material balance, heat balance and theoretical combustion temperature constraints of the tuyere area, the material balance and heat balance constraints of the high-temperature area, the material balance and heat balance constraints of the low-temperature area, and the material balance and heat balance constraints of the entire furnace.

[0025] The final blast furnace Rist operation line involving hydrogen is determined based on the final coordinates of point B and the coordinates of point Z.

[0026] Based on the blast furnace Rist operating line with hydrogen participation, various energy consumption indicators under different hydrogen-rich smelting conditions are predicted; the energy consumption indicators include material balance, reduction degree distribution, gas generation process, theoretical combustion temperature in the tuyeres area, thermal balance in the high-temperature zone, thermal balance in the low-temperature zone, overall thermal balance of the blast furnace, final fuel ratio, C consumption per ton of iron and CO2 emissions, theoretical carbon consumption per ton of iron and carbon saving potential.

[0027] Optionally, the coordinates of point G are (x... G y G );

[0028] Where, x G =1, y A ω is the ordinate of point A on the Rist operating line of the blast furnace where hydrogen is involved; j represents the type of iron ore used as feedstock for the blast furnace; ω(Fe2O3) j ω(FeO) represents the content of ferric oxide (Fe2O3) in the iron ore used as feedstock for blast furnaces. j ω(TFe) represents the content of iron oxide (FeO) in the iron ore used as feedstock for blast furnaces. j The content of total iron (TFe) in the iron ore used as feedstock for blast furnaces;

[0029] The coordinates of point W are (x W y W );

[0030] in, y W =1.056; K CO The equilibrium constant for the reduction of FeO by carbon dioxide (CO) at 1000℃; φ is the equilibrium constant for the reduction of FeO by H2 at 1000℃. COThis represents the volume percentage of CO in the reducing gas at 1000℃ inside the blast furnace. This represents the volume percentage of H2 in the reducing gas at 1000℃ inside the blast furnace.

[0031] Optionally, based on the principle of triangle similarity, the furnace working efficiency η is... shaft The coordinates of point Z are determined by the coordinates of point W and point G, specifically including:

[0032] Based on the principle of triangle similarity, the opposite sides of line GZ and line GW are proportional.

[0033] The coordinates of the Z point are determined based on the proportional relationship between the opposite sides; the coordinates of the Z point are (x... Z y Z ), x Z =η shaft ×(x w -1)+1,y Z =y A -η shaft ×(y A -y w ), η shaft The furnace body's working efficiency.

[0034] Optionally, the assignment of values ​​to the direct reduction degree and the current fuel ratio, based on the carbon-oxygen balance in front of the vent and the material and heat balance constraints of each region, involves iterating the direct reduction degree and the current fuel ratio using a cyclic iterative method to determine the final coordinates and final fuel ratio of point B. Specifically, this includes:

[0035] Assign values ​​to the direct reduction degree and the current fuel ratio to determine the initial coordinates of point B; the direct reduction degree is the ordinate of the initial coordinates of point B.

[0036] The initial blast furnace Rist operation line is determined based on the initial coordinates of point B and the coordinates of point Z.

[0037] Determine the blast furnace oxygen molar number and the carbon and fuel molar number in front of the tuyere based on the initial blast furnace Rist operating line.

[0038] Based on the carbon-oxygen balance in front of the air outlet, the direct reduction degree is continuously iterated using a cyclic iterative method until the number of oxygen moles in the blower equals the number of carbon moles in front of the air outlet, and the coordinates of point B are determined.

[0039] Based on the ordinate of the coordinates of point B, the degree of hydrogen reduction, and the current fuel ratio, calculate the material balance and heat balance of each region, as well as the constraints of the material balance and heat balance of each region. Use a cyclic iterative method to continuously iterate the current fuel ratio and the coordinates of point B to determine the final coordinates of point B and the final fuel ratio.

[0040] Optionally, determining the blast furnace oxygen molar number and the carbon-fuel molar number before the tuyeres based on the initial blast furnace Rist operating line specifically includes:

[0041] The slope of line AB is determined based on the initial coordinates of point B and the coordinates of point Z.

[0042] The ordinate of point E on the blast furnace Rist operation line with hydrogen participation is determined based on the slope of the straight line AB and the degree of direct reduction.

[0043] The number of oxygen moles in the blower is determined based on the ordinate of point E; the number of oxygen moles per ton of iron blower = -(y E +y f +y θ )×[Fe]×10÷56;y E Let y be the ordinate of point E; f =(4×[Si]+1.02×[Mn]+4.52×[P]+2.75×[V]+2.33[Ti]) / [Fe], y f The amount of oxygen introduced by non-ferrous oxides, y θ The equivalent H2 and oxygen content of the injected hydrogen-containing substances are given. [Si] is the mass fraction of silicon (Si) in the molten iron, [Mn] is the mass fraction of manganese (Mn) in the molten iron, [P] is the mass fraction of phosphorus (P) in the molten iron, [V] is the mass fraction of vanadium (V) in the molten iron, [Ti] is the mass fraction of titanium (Ti) in the molten iron, and [Fe] is the mass fraction of iron (Fe) in the molten iron.

[0044] The carbon-fuel molar number before the vent is determined based on the carbon balance and the direct reduction degree; the carbon-fuel molar number before the vent = Cb ÷ 12 + C 喷 Cb = C 总 -C 渗 -C 非铁 -C 尘 -[Fe]×r d ×10×12÷56, Cb is the mass of carbon C burned in the fuel, C 渗 C represents the amount of carburization in the molten iron. 尘 The amount of carbon carried out by furnace dust; C 总 The total carbon carried by the fuel entering the furnace includes carbon from the coke and carbon from the pulverized coal, C. 喷 r is the number of moles of carbon C that can burn to CO in the hydrogen-rich medium being injected; d The degree of direct reconstruction is determined by the coordinates of point B.

[0045] Optionally, the assignment of values ​​to the direct reduction degree and the current fuel ratio, based on the carbon-oxygen balance in front of the vent and the material and heat balance constraints of each region, involves iterating the direct reduction degree and the current fuel ratio using a cyclic iterative method to determine the final coordinates and final fuel ratio of point B. Specifically, this includes:

[0046] The direct reduction degree and the current fuel ratio are assigned values ​​to determine whether carbon and oxygen are in balance, and a first judgment result is obtained.

[0047] If the first judgment result is represented as carbon-oxygen balance, the material balance and heat balance of each region are calculated by substituting the direct reduction degree, the hydrogen reduction degree and the current fuel ratio.

[0048] Determine whether the thermal balance of each region meets the thermal balance constraint conditions of each region, and obtain the second judgment result;

[0049] If the second judgment result indicates that the heat balance of each region meets the heat balance constraint conditions of each region, determine the final coordinates of point B and the final fuel ratio.

[0050] If the second judgment result indicates that the heat balance of each region does not meet the heat balance constraint conditions of each region, the current fuel ratio is adjusted iteratively, and the blast furnace raw material conditions and the injection parameters are readjusted.

[0051] If the first judgment result indicates that carbon and oxygen are not in balance, the direct reduction degree is reassigned and the result is returned as "Judging whether carbon and oxygen are in balance, obtaining the first judgment result".

[0052] Optionally, the changing trends of various energy consumption indicators of the hydrogen-rich blast furnace under different operating parameters can be analyzed by adjusting the blast furnace raw material conditions, product parameters, and injection parameters.

[0053] According to specific embodiments provided by the present invention, the following technical effects are disclosed: The present invention provides a method for monitoring blast furnace energy consumption and predicting hydrogen-rich smelting based on the Rist operating line. A blast furnace operating line with hydrogen participation is established based on the Rist operating line theory, and a combined calculation model of the blast furnace tuyeres, high-temperature zone, low-temperature zone, and the entire blast furnace is established based on the hydrogen-participating blast furnace operating line. This automatically analyzes various energy consumption data, accurately reconstructs the ore reduction situation and gas generation process within the production blast furnace, not only improving the blast furnace energy consumption monitoring effect, but also allowing analysis of the changing trends of various energy consumption indicators of the hydrogen-rich blast furnace under different operating parameters by adjusting raw material conditions, product parameters, and injection parameters, thus predicting various energy consumption data under different hydrogen-rich smelting conditions. Attached Figure Description

[0054] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0055] Figure 1 The flowchart of the blast furnace energy consumption monitoring method based on the Rist operating line provided by the present invention is shown below.

[0056] Figure 2 This is a schematic diagram of the hydrogen-involved blast furnace Rist operation line provided by the present invention;

[0057] Figure 3 This is a flowchart of the hydrogen-rich blast furnace prediction process provided by the present invention;

[0058] Figure 4 This invention provides an analysis and prediction chart of various energy consumption data in practical applications.

[0059] Figure 5 This is a schematic diagram of the main interface of the computational model implemented in VB provided by this invention;

[0060] Figure 6 This is a schematic diagram illustrating the energy-saving and emission-reduction potential of hydrogen-rich blast furnaces under different hearth gas compositions provided by the present invention.

[0061] Figure 7 The graph shows the relationship between heat consumption per ton of iron, coke ratio, and direct reduction C consumption under different furnace gas compositions provided by this invention. Detailed Implementation

[0062] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0063] The purpose of this invention is to provide a method for monitoring blast furnace energy consumption and predicting hydrogen-rich smelting based on the Rist operating line. This method can automatically analyze various energy consumption data, accurately reconstruct the ore reduction situation and gas generation process in the blast furnace, improve the blast furnace energy consumption monitoring effect, and predict blast furnaces under different hydrogen-rich smelting conditions.

[0064] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0065] Example 1

[0066] Figure 1 The flowchart of the blast furnace energy consumption monitoring method based on the Rist operating line provided by the present invention is as follows: Figure 1 As shown, this invention provides a blast furnace energy consumption monitoring method based on the Rist operating line, comprising:

[0067] Step 101: Import blast furnace production data and calculate hydrogen utilization rate based on the blast furnace production data and hydrogen balance; the blast furnace production data includes raw material and fuel conditions, product parameters, and injection conditions; the raw material and fuel conditions include iron ore type, furnace charge structure, fuel ratio, raw material and fuel chemical composition, and blast parameters; the product parameters include molten iron composition, slag composition, furnace dust composition, furnace dust quantity, and furnace top gas composition; the injection parameters include injection medium type, injection volume, injection temperature, injection location, and hydrogen utilization rate; the blast parameters include blast humidity, blast temperature, oxygen enrichment rate, and oxygen purity; the fuel ratio includes coke ratio and coal ratio.

[0068] In practical applications, the input data module in the blast furnace Rist operation line imports the raw material conditions, product parameters, and injection conditions of the blast furnace from the data port into the calculation module and performs normalization processing.

[0069] Step 102: Calculate the degree of hydrogen reduction based on the hydrogen utilization rate.

[0070] In practical applications, the blast furnace Rist operation line calculation module first calculates the hydrogen utilization rate. Calculations and the reducing power of hydrogen While the volumetric H2O content of coal gas is generally not measured during production, its utilization rate in blast furnaces using hydrogen-rich injection media is significant. The calculation module uses the conservation of hydrogen element, subtracting the H2 content in the top coal gas from the total hydrogen content to obtain the amount of hydrogen participating in reduction, thus determining the hydrogen utilization rate. Calculations and the reducing power of hydrogen Calculate according to formulas (1) and (2):

[0071]

[0072]

[0073] in, The utilization rate of hydrogen is v%, and vH2O is the amount of water generated from the reduction of hydrogen, in Nm³. 3 / tFe; [Fe] is the mass fraction of Fe in the molten iron, %; ΣvH2 is the total volume of hydrogen entering the furnace, including H2 from the cracking of raw materials and hot air, as well as injected H2, Nm 3 / tFe;v gThe volume of gas at the top of the blast furnace for smelting pig iron is calculated according to formula (3), m 3 / tFe; The percentage of H2 and CH4 by volume in the top gas of a pig iron blast furnace in a smelting unit, expressed as %.

[0074]

[0075] C g The amount of carbon in the top gas of a pig iron blast furnace in a smelting unit is calculated according to formula (4); These represent the volume percentages of CO2 and CO in the top gas of pig iron blast furnaces in smelting units, respectively (%).

[0076] C g =C 总 -C 渗 -C 尘 (4)

[0077] C 总 The total amount of carbon fed into the furnace, including carbon in coke and pulverized coal, kg / tFe; C 渗 Carburization amount in molten iron, kg / tFe; C 尘 The amount of carbon carried out by furnace dust is expressed in kg / tFe.

[0078] therefore,

[0079] Step 103: Determine the coordinates of point A and point E on the blast furnace Rist operation line where hydrogen is involved, based on the blast furnace production data.

[0080] Figure 2 This is a schematic diagram of the hydrogen-involved blast furnace Rist operation line provided by the present invention, as shown below. Figure 2 As shown, the coordinates of points A and E on the blast furnace Rist operating line with hydrogen participation are determined based on the conditions of the raw materials entering the furnace, the composition of the molten iron, and the composition of the gas at the top of the furnace.

[0081] The ordinate of point A is y A The amount of oxygen introduced into the furnace charge, which is also the amount of oxygen that needs to be removed in direct and indirect reduction. d +y i .

[0082]

[0083] The x-coordinate of point A is x A Oxidation degree of coal gas:

[0084] in, The volume percentage of H2O in the top gas of the pig iron blast furnace in a smelting unit is calculated according to formula (5);

[0085]

[0086] Point E has an x-coordinate of 0 and a y-coordinate of 0. E This represents the sum of the oxygen and H2 carried in by the gas before the vent.

[0087] x E =0, y E =-(y f +y b +y θ (6)

[0088] Where y f The amount of oxygen introduced by non-ferrous oxides is calculated according to formula (7), where [Si], [Mn], [P], [V], and [Ti] are the mass fractions of Si, Mn, P, V, and Ti in the molten iron, in %;

[0089] y θ The amount of hydrogen-containing substance H2 and oxygen injected is calculated according to formula (8), vH 2喷 The volume of hydrogen molecules in the hydrogen-rich medium being sprayed is Nm. 3 / tFe, mO is the mass of oxygen atoms in the hydrogen-rich sprayed medium, kg / tFe;

[0090] y b The amount of oxygen introduced by the blower is calculated according to formula (9), v blast For ton iron blower volume, Nm 3 / tFe, φO 2_b The oxygen volume fraction in the blower air, %;

[0091] y f =(4×[Si]+1.02×[Mn]+4.52×[P]+2.75×[V]+2.33[Ti]) / [Fe] (7)

[0092]

[0093]

[0094] Step 104: Determine the blast furnace Rist operation line involving hydrogen based on the coordinates of point A and point E.

[0095] Step 105: Determine the direct reduction degree based on the hydrogen-involved blast furnace Rist operating line.

[0096] Step 106: Monitor blast furnace energy consumption based on the direct reduction degree and the hydrogen reduction degree to determine various energy consumption data; the energy consumption data includes material balance, reduction degree distribution, gas generation process, theoretical combustion temperature in the tuyeres area, thermal balance in the high-temperature zone, thermal balance in the low-temperature zone, overall thermal balance of the blast furnace, furnace working efficiency, C consumption per ton of iron and CO2 emissions, theoretical carbon consumption and carbon saving potential.

[0097] Example 2

[0098] A method for predicting hydrogen-rich smelting based on the Rist operating line determines the final Rist operating line of the blast furnace with hydrogen participation through a cyclic iterative method under different hydrogen-rich smelting conditions, including:

[0099] Step 201: Import blast furnace raw material conditions, product parameters, injection parameters, and furnace working efficiency η shaft The blast furnace raw material and fuel conditions include iron ore type, furnace charge structure, fuel ratio, and raw material and fuel chemical composition; the product parameters include molten iron composition, slag composition, furnace dust composition, and furnace dust quantity; the injection parameters include injection medium type, injection volume, injection temperature, injection location, and hydrogen utilization rate; the blast parameters include blast humidity, blast temperature, oxygen enrichment rate, and oxygen purity.

[0100] Step 202: Based on the blast furnace raw material conditions, the product parameters, and the furnace working efficiency η shaft The injection parameters determine the coordinates of point G and point W in the Rist operating line of a blast furnace with hydrogen participation.

[0101] The coordinates of point G are (x G y G ); where x G =1, y A ω is the ordinate of point A on the Rist operating line of the blast furnace where hydrogen is involved; j represents the type of iron ore used as feedstock for the blast furnace; ω(Fe2O3) j ω(FeO) represents the content of ferric oxide (Fe2O3) in the iron ore used as feedstock for blast furnaces. j ω(TFe) represents the content of iron oxide (FeO) in the iron ore used as feedstock for blast furnaces. j The content of total iron (TFe) in the iron ore used as feedstock for blast furnaces;

[0102] The coordinates of point W are (x W y W );in, y W =1.056; K CO The equilibrium constant for the reduction of FeO by carbon dioxide (CO) at 1000℃; φ is the equilibrium constant for the reduction of FeO by H2 at 1000℃. CO This represents the volume percentage of CO in the reducing gas at 1000℃ inside the blast furnace. This represents the volume percentage of H2 in the reducing gas at 1000℃ inside the blast furnace.

[0103] Step 203: Based on the furnace working efficiency η shaft Based on the principle of triangle similarity, the coordinates of point W and the coordinates of point G determine the coordinates of point Z.

[0104] Where, η shaft To improve the working efficiency of the furnace body.

[0105] In practical applications, the coordinates of point Z are determined based on the proportional relationship between opposite sides; the coordinates of point Z are (xZ, yZ), where x... Z =η shaft ×(x w -1)+1,y Z =y A -η shaft ×(y A -y w ).

[0106] Step 204: Assign values ​​to the direct reduction degree and the current fuel ratio. Based on the carbon-oxygen balance in front of the tuyere and the material and heat balance constraints of each region, use a cyclic iterative method to continuously iterate the direct reduction degree and the current fuel ratio to determine the final coordinates of point B and the final fuel ratio. The heat balance constraints of each region include the material balance, heat balance and theoretical combustion temperature constraints of the tuyere area, the material balance and heat balance constraints of the high-temperature area, the material balance and heat balance constraints of the low-temperature area, and the material and heat balance constraints of the entire furnace.

[0107] In practical applications, based on the [C,O] balance, the coordinates of the key point B on the operation line are determined using a cyclic iterative method. A straight line is drawn between points Z and B, and the fuel ratio is determined based on the material balance and heat balance constraints of each region to complete the module calculation. Figure 3 The flowchart for predicting hydrogen-rich blast furnaces provided by this invention includes the following calculation steps: Figure 3 As shown.

[0108] Step 204 specifically includes: assigning values ​​to the direct reduction degree and the current fuel ratio to determine the initial coordinates of point B; the direct reduction degree is the ordinate of the initial coordinates of point B; determining the initial blast furnace Rist operating line based on the initial coordinates of point B and the coordinates of point Z; determining the blast oxygen molar number and the carbon-fuel molar number in front of the tuyere based on the initial blast furnace Rist operating line; and iterating the direct reduction degree continuously using a cyclic iterative method based on the carbon-oxygen balance in front of the tuyere until the blast oxygen molar number equals the carbon-fuel molar number in front of the tuyere, thereby determining the coordinates of point B.

[0109] Based on the ordinate of the coordinates of point B, the degree of hydrogen reduction, and the current fuel ratio, calculate the material balance and heat balance of each region, as well as the constraints of the material balance and heat balance of each region. Use a cyclic iterative method to continuously iterate the current fuel ratio and the coordinates of point B to determine the final coordinates of point B and the final fuel ratio.

[0110] The determination of the blast furnace oxygen molar number and the carbon and fuel molar number before the tuyeres based on the initial blast furnace Rist operating line specifically includes: determining the slope of the straight line AB based on the initial coordinates of point B and the coordinates of point Z; determining the ordinate of point E on the blast furnace Rist operating line with hydrogen participation based on the slope of the straight line AB and the direct reduction degree; determining the blast furnace oxygen molar number based on the ordinate of point E; the blast furnace oxygen molar number per ton of iron = -(y E +y f +y θ )×[Fe]×10÷56;y E Let y be the ordinate of point E; f =(4×[Si]+1.02×[Mn]+4.52×[P]+2.75×[V]+2.33[Ti]) / [Fe], y f The amount of oxygen introduced by non-ferrous oxides, y θ The amount of hydrogen-containing substance H2 and oxygen injected is defined as follows: [Si] is the mass fraction of silicon (Si) in the molten iron; [Mn] is the mass fraction of manganese (Mn) in the molten iron; [P] is the mass fraction of phosphorus (P) in the molten iron; [V] is the mass fraction of vanadium (V) in the molten iron; [Ti] is the mass fraction of titanium (Ti) in the molten iron; and [Fe] is the mass fraction of iron (Fe) in the molten iron. The number of molar carbon fuels before the tuyeres is determined based on the carbon balance and the direct reduction degree. The number of molar carbon fuels before the tuyeres = Cb ÷ 12 + C 喷 Cb = C 总 -C 渗 -C 非铁 -C 尘 -[Fe]×r d ×10×12÷56, Cb is the mass of carbon C burned in the fuel, C 渗 C represents the amount of carburization in the molten iron. 尘 The amount of carbon carried out by furnace dust; C 总The total carbon carried by the fuel entering the furnace includes carbon from the coke and carbon from the pulverized coal, C. 喷 r is the number of moles of carbon C that can burn to CO in the hydrogen-rich medium being injected; d The degree of direct reconstruction is determined by the coordinates of point B.

[0111] Specifically, this includes: assigning values ​​to the direct reduction degree and the current fuel ratio, determining whether carbon and oxygen are in balance, and obtaining a first determination result; if the first determination result indicates carbon and oxygen balance, calculating the material balance and heat balance of each region by substituting the direct reduction degree, the hydrogen reduction degree, and the current fuel ratio; determining whether the heat balance of each region meets the heat balance constraints of each region, and obtaining a second determination result; if the second determination result indicates that the heat balance of each region meets the heat balance constraints of each region, determining the final coordinates of point B and the final fuel ratio; if the second determination result indicates that the heat balance of each region does not meet the heat balance constraints of each region, adjusting and iterating the current fuel ratio, and readjusting the blast furnace raw material conditions and the injection parameters; if the first determination result indicates that carbon and oxygen are not in balance, reassigning the direct reduction degree, and returning "determining whether carbon and oxygen are in balance, obtaining the first determination result".

[0112] Step 205: Determine the final blast furnace Rist operation line with hydrogen participation based on the final coordinates of point B and the coordinates of point Z.

[0113] Step 206: Predict various energy consumption indicators under different hydrogen-rich smelting conditions based on the final hydrogen-involved blast furnace Rist operating line; the energy consumption indicators include material balance, reduction degree distribution, gas generation process, theoretical combustion temperature in the tuyeres area, thermal balance in the high-temperature zone, thermal balance in the low-temperature zone, overall thermal balance of the blast furnace, final fuel ratio, C consumption per ton of iron and CO2 emissions, theoretical carbon consumption per ton of iron and carbon saving potential.

[0114] In practical applications, the changing trends of various energy consumption indicators of hydrogen-rich blast furnaces under different operating parameters are analyzed by adjusting the blast furnace raw material conditions, product parameters, and injection parameters.

[0115] In practical applications, the production blast furnace operation line AE is determined and drawn based on points A and E. The direct intersection point with x=1 can then be used to calculate the degree of reduction r. d Based on the calculated r d and r H2 By inputting the material and heat balance calculation modules for each area of ​​the blast furnace, a joint calculation was established for the blast furnace tuyeres, high-temperature zone, low-temperature zone, and the entire blast furnace. This yielded various energy consumption data, such as the theoretical combustion temperature (RAFT) of the tuyeres area, furnace efficiency, C consumption per ton of iron, and CO2 emissions. Figure 4 As shown.

[0116] Based on the Rist operating line theory of blast furnaces, this invention establishes a comprehensive calculation model integrating the blast furnace tuyeres, high-temperature zone, low-temperature zone, and the entire blast furnace. A prediction method for hydrogen-rich smelting in blast furnaces is also established, enabling the calculation model to simultaneously perform analytical and predictive functions.

[0117] This invention can perform calculations based on the characteristics of different blast furnaces with different mineral types and operating conditions, making it highly adaptable and providing more accurate calculation results; it can also analyze the energy-saving and emission-reduction potential under different hydrogen-rich smelting conditions.

[0118] This invention utilizes the Visual Basic 6.0 environment for program compilation, which can effectively solve the problem of large and complex calculation processes. It clarifies the complex material and heat balance relationships in the blast furnace and generates a clear, easy-to-use calculation, analysis, and prediction software. It is easy to operate and control, and also has data export, summarization, and organization functions. It frees blast furnace workers from data recording and calculation, and features high calculation efficiency, wide applicability, and strong applicability.

[0119] This invention delegates the massive computational process to computers, effectively saving costs. It is of great significance for promoting high-precision, automated, and intelligent control of blast furnaces, and also provides strong support for green ironmaking, energy conservation, and emission reduction in blast furnaces.

[0120] Example 3

[0121] Figure 5 This is a schematic diagram of the main interface of the computational model implemented in VB provided by this invention, as shown below. Figure 5 As shown, taking any blast furnace as an example, the prediction process is as follows.

[0122] Based on the production conditions of a blast furnace in China, this invention is used to import the composition of the on-site ore raw materials, fuel composition, furnace top gas conditions, product molten iron composition and temperature, and other generation conditions into the input data module, and then click the confirmation button and calculation preparation to perform data normalization processing.

[0123] Click on the blast furnace Rist operation line diagram calculation module. Based on the H balance, the hydrogen utilization rate can be determined. The coordinates of points A and E are then calculated in the background. Based on the AE operation line, r can be determined. d .

[0124] From the calculated r H2 r d The calculation results, combined with the material and heat balance calculations of each area of ​​the blast furnace, can yield important parameters such as the working efficiency of the blast furnace body, the energy consumption per ton of iron, the various C consumptions of the blast furnace, and CO2 emissions. Through material balance calculations, the calculation method proposed in this invention has a calculation error within 0.5%. Table 1 is an energy consumption monitoring table for a certain production blast furnace, and its calculation results are shown in Table 1.

[0125] Table 1

[0126]

[0127] Based on the actual blast furnace heat load and furnace efficiency as boundary conditions, the hydrogen injection rate at the tuyere is adjusted using the blast furnace Rist operation line prediction module. Iterative calculations are then performed to obtain the energy-saving and emission-reduction potential of hydrogen-enriched blast furnaces under different hearth gas compositions. Figures 6-7 As shown, adjusting the hydrogen injection rate gradually increases the utilization rate of the furnace top gas and gradually decreases the direct reduction degree. With the increase of hydrogen reduction in the blast furnace, the heat consumption per ton of iron decreases, and the carbon consumption decreases. When pure hydrogen is injected, the carbon consumption per ton of iron decreases by a maximum of 152 kg / tFe.

[0128] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the systems disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the descriptions are relatively simple; relevant parts can be referred to the method section.

[0129] This document uses specific examples to illustrate the principles and implementation methods of the present invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of the present invention. Furthermore, those skilled in the art will recognize that, based on the ideas of the present invention, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. A blast furnace energy consumption monitoring method based on Rist operating line, applied to blast furnace hydrogen-rich smelting, characterized in that, The method comprises the following steps: Importing blast furnace production data and calculating hydrogen utilization rate according to the blast furnace production data and hydrogen balance; The blast furnace production data comprises blast furnace raw fuel conditions, product parameters and injection parameters; Calculating hydrogen reduction degree according to the hydrogen utilization rate; Based on the blast furnace production data, determine the coordinates of points A and E on the blast furnace Rist operation line involving hydrogen. The x-coordinate of the blast furnace Rist operation line involving hydrogen, [n(O)+n(H2)] / [n(C)+n(H2)], represents the number of moles of oxygen and hydrogen combined per mole of (C+H2), reflecting the destination of oxygen and hydrogen. The y-coordinate, [n(O)+n(H2)] / n(Fe), represents the source of oxygen and hydrogen per mole of Fe during smelting. The x-coordinate of point E... E =0, the y-coordinate of point E E =-(y f +y b +y θ ), y f y represents the amount of oxygen introduced by non-ferrous oxides. b The amount of oxygen brought in by the blower, y θ To inject hydrogen-containing substances H2 and oxygen, vH 2喷 The volume of hydrogen molecules in the hydrogen-rich medium being sprayed is denoted as mO, the mass of oxygen atoms in the hydrogen-rich medium being sprayed is denoted as [Fe], and the mass fraction of Fe in the molten iron is denoted as [Fe]. Determining hydrogen-involved blast furnace Rist operation line according to the A point coordinates and the E point coordinates; Determining direct reduction degree according to the hydrogen-involved blast furnace Rist operation line; Monitoring blast furnace energy consumption, determining energy consumption data according to the direct reduction degree and the hydrogen reduction degree; the energy consumption data comprises material balance, reduction degree distribution, coal gas generation process, theoretical combustion temperature of tuyere area, high temperature zone heat balance, low temperature zone heat balance, whole blast furnace heat balance, blast furnace shaft working efficiency, ton iron C consumption and CO2 emission, ton iron theoretical carbon consumption and carbon saving potential.

2. The Rist operating line based blast furnace energy consumption monitoring method as claimed in claim 1 wherein, The method for calculating hydrogen utilization rate according to the blast furnace production data and hydrogen balance comprises the following steps: The utilization of hydrogen is calculated using the formula Y = 100 - (H2O2 / H2O) x 100 wherein, is the utilization of hydrogen, vH2O is the amount of water produced by the reduction of hydrogen; ∑ v H2 is the total volume of hydrogen into the furnace, which includes the hydrogen produced by water cracking in the raw fuel and hot air, and the equivalent hydrogen injected into the hydrogen-rich medium; v g is the volume of blast furnace top gas per unit of pig iron smelting; is the volume percentage of hydrogen in the blast furnace top gas per unit of pig iron smelting; is the volume percentage of methane in the blast furnace top gas per unit of pig iron smelting; is the volume percentage of CO2 in the blast furnace top gas per unit of pig iron smelting; is the volume percentage of CO in the blast furnace top gas per unit of pig iron smelting; C 总 is the total amount of carbon into the furnace, including carbon in coke and coal powder; C 渗 is the carbon content in molten iron; C 尘 is the amount of carbon carried out by the dust.

3. The Rist operating line based blast furnace energy consumption monitoring method as claimed in claim 2, wherein, the degree of reduction of the hydrogen is: Wherein, [Fe] is the mass fraction of iron in molten iron.

4. A method for predicting hydrogen-enriched smelting based on Rist operating lines, characterized by, The method is applied to blast furnace hydrogen-rich smelting, and the final hydrogen-involved blast furnace Rist operation line is determined through cyclic iteration under different hydrogen-rich smelting conditions; the horizontal coordinate of the hydrogen-involved blast furnace Rist operation line is [n(O)+n(H2)] / [n(C)+n(H2)], which represents the number of moles of oxygen and hydrogen combined per mole of (C+H2), and reflects the direction of oxygen and hydrogen; the vertical coordinate is [n(O)+n(H2)] / n(Fe), which represents the source of oxygen and hydrogen per mole of Fe smelting, including: introducing blast furnace raw fuel conditions, product parameters, injection parameters and shaft working efficiency η shaft ; the blast furnace raw fuel conditions include iron ore type, burden structure, fuel ratio, raw fuel chemical composition, blast parameters; the product parameters include molten iron composition, slag composition, furnace dust composition, furnace dust amount; the injection parameters include injection medium type, injection amount, injection temperature, injection position, hydrogen utilization rate; the blast parameters include blast humidity, blast temperature, oxygen enrichment rate and oxygen purity; According to the blast furnace raw fuel conditions, the product parameters, the shaft working efficiency η shaft and the injection parameters, the G point coordinates and the W point coordinates in the blast furnace Rist operating line with hydrogen participation are determined; Based on the principle of triangle similarity, according to the working efficiency η of the furnace shaft shaft , the W point coordinates and the G point coordinates to determine the Z point coordinates; The direct reduction degree and the current fuel ratio are assigned, and the direct reduction degree and the current fuel ratio are continuously iterated based on the carbon-oxygen balance before the tuyere and the material balance and heat balance constraint conditions of each region, to determine the final B point coordinates and the final fuel ratio, which comprises the following steps: assigning the direct reduction degree and the current fuel ratio to determine the initial B point coordinates; the direct reduction degree is the vertical coordinate of the initial B point coordinates; determining the initial blast furnace Rist operation line according to the initial B point coordinates and the Z point coordinates; determining the number of moles of blast oxygen and the number of moles of carbon combustion before the tuyere based on the initial blast furnace Rist operation line; continuously iterating the direct reduction degree based on the carbon-oxygen balance before the tuyere until the number of moles of blast oxygen is equal to the number of moles of carbon combustion before the tuyere, to determine the B point coordinates; calculating the material balance and heat balance of each region according to the vertical coordinate of the B point coordinates, the hydrogen reduction degree and the current fuel ratio, and continuously iterating the current fuel ratio and the B point coordinates based on the material balance and heat balance constraint conditions of each region, to determine the final B point coordinates and the final fuel ratio; the heat balance constraint conditions of each region comprise the material balance, heat balance and theoretical combustion temperature constraint conditions of the tuyere area, the material balance and heat balance constraint conditions of the high temperature zone, the material balance, heat balance constraint conditions of the low temperature zone, and the material balance and heat balance constraint conditions of the whole blast furnace; Determining the final hydrogen-involved blast furnace Rist operation line according to the final B point coordinates and the Z point coordinates. According to the final hydrogen-involved blast furnace Rist operation line, energy consumption indexes under different hydrogen-rich smelting conditions are predicted, including material balance, reduction degree distribution, coal gas generation process, theoretical combustion temperature of tuyere area, high-temperature zone heat balance, low-temperature zone heat balance, overall heat balance of blast furnace, final fuel ratio, C consumption per ton of iron, CO2 emission, theoretical carbon consumption per ton of iron, and carbon-saving potential. The blast oxygen mole number and the carbon combustion mole number before tuyere are determined based on the initial blast furnace Rist operation line, including determining the slope of straight line AB according to the B-point initial coordinates and the Z-point coordinates, determining the vertical coordinate of E-point on the hydrogen-involved blast furnace Rist operation line according to the slope of straight line AB and the direct reduction degree, determining the blast oxygen mole number according to the vertical coordinate of E-point, and determining the carbon combustion mole number before tuyere according to carbon balance and the direct reduction degree. The ordinate y of point E E = -(y f +y b +y θ ), y f is the oxygen quantity brought in by non-ferrous oxides, y b is the oxygen quantity brought in by blast, y θ is the oxygen quantity brought in by spraying hydrogen-containing substance H2 and oxygen, vH 2喷 is the hydrogen molecule volume in the sprayed hydrogen-rich medium, mO is the oxygen atom mass in the sprayed hydrogen-rich medium, and [Fe] is the mass fraction of Fe in the molten iron.

5. The Rist operating line based hydrogen rich smelting predictive method of claim 4, wherein, The G point coordinates are (x G , y G ) wherein x G = 1, y A is the ordinate of point A on the Rist operating line of the blast furnace with hydrogen participation; j is the type of the blast furnace raw material iron ore; ω(Fe2O3) j is the content of the iron trioxide Fe2O3 in the blast furnace raw material iron ore; ω(FeO) j is the content of the iron oxide FeO in the blast furnace raw material iron ore; ω(TFe) j is the content of the total iron TFe in the blast furnace raw material iron ore; The W point coordinates are (x W , y W ); wherein, y W = 1.056; K CO is the equilibrium constant of FeO reduction by carbon monoxide CO at 1000℃; is the equilibrium constant of FeO reduction by H2 at 1000℃; φ CO is the volume fraction of CO in the reducing gas at 1000℃ in the blast furnace; is the volume fraction of H2 in the reducing gas at 1000℃ in the blast furnace.

6. The Rist operating line based hydrogen-rich metallurgical prediction method of claim 5, wherein, The principle of triangle similarity is used to determine the Z point coordinate according to the furnace shaft working efficiency η shaft , the W point coordinate and the G point coordinate, specifically comprising: According to the triangle similarity principle, it is determined that the opposite sides of the straight line GZ and the straight line GW are in proportional relationship According to the proportional relationship between the two sides, the Z point coordinates are determined; the Z point coordinates are (x Z , y Z ), x Z = η shaft × (x w -1) + 1, y Z =y A - η shaft × (y A -y w ), and η shaft is the working efficiency of the furnace shaft.

7. The Rist operating line based hydrogen rich smelting predictive method of claim 4, wherein, The oxygen mole number of the blast = - (y E +y f +y θ ) × [Fe] × 10 ÷ 56; y E is the ordinate of the E point; y f = (4 × [Si] + 1.02 × [Mn] + 4.52 × [P] + 2.75 × [V] + 2.33 × [Ti]) ÷ [Fe], y f is the oxygen quantity brought by non-iron oxides, y θ is the equivalent H2 and oxygen quantity of the injected hydrogen-containing substance, [Si] is the mass fraction of silicon Si in the molten iron, [Mn] is the mass fraction of manganese Mn in the molten iron, [P] is the mass fraction of phosphorus P in the molten iron, [V] is the mass fraction of vanadium V in the molten iron, [Ti] is the mass fraction of titanium Ti in the molten iron, and [Fe] is the mass fraction of iron Fe in the molten iron. The number of moles of carbon combustion before the tuyere = Cb ÷ 12 + C 喷 ; Cb = C 总 -C 渗 -C 非铁 -C 尘 -[Fe] × r d × 10 × 12 ÷ 56, Cb is the mass of carbon C burned in the fuel, C 渗 is the carbon content in the molten iron; C 尘 is the amount of carbon carried out by the furnace dust; C 总 is the total amount of carbon carried into the furnace by the fuel, which includes the carbon in the coke and the carbon in the coal powder, C 喷 is the number of moles of carbon C that can be burned into CO in the injected hydrogen-rich medium; r d is the direct reduction degree, determined by the B point coordinates.

8. The Rist operating line based hydrogen rich smelting predictive method of claim 4, wherein, The direct reduction degree and the current fuel ratio are assigned, and the direct reduction degree and the current fuel ratio are iterated based on the carbon-oxygen balance before tuyere and the material balance and heat balance constraints of each region to determine the final B-point coordinates and the final fuel ratio, including assigning the direct reduction degree and the current fuel ratio, determining whether the carbon-oxygen is balanced to obtain a first determination result. If the first determination result indicates that the carbon-oxygen is balanced, the direct reduction degree, the hydrogen reduction degree, and the current fuel ratio are brought in to calculate the material balance and heat balance of each region. It is determined whether the heat balance of each region meets the heat balance constraints of each region to obtain a second determination result. If the second determination result indicates that the heat balance of each region meets the heat balance constraints of each region, the final B-point coordinates and the final fuel ratio are determined. If the second determination result indicates that the heat balance of each region does not meet the heat balance constraints of each region, the current fuel ratio is adjusted, and the blast furnace raw fuel conditions and the injection parameters are re-adjusted. If the first determination result indicates that the carbon-oxygen is not balanced, the direct reduction degree is re-assigned, and the first determination result is returned. The change trend of each energy consumption index of the hydrogen-rich blast furnace under different operation parameters is analyzed by adjusting the blast furnace raw fuel conditions, the product parameters, and the injection parameters.

9. The Rist operating line based hydrogen rich smelting predictive method according to any one of claims 4-8, characterized in that, ​

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