CN113667781A - Method for reducing fuel ratio of blast furnace - Google Patents
Method for reducing fuel ratio of blast furnace Download PDFInfo
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- CN113667781A CN113667781A CN202110865369.9A CN202110865369A CN113667781A CN 113667781 A CN113667781 A CN 113667781A CN 202110865369 A CN202110865369 A CN 202110865369A CN 113667781 A CN113667781 A CN 113667781A
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Abstract
The invention particularly relates to a method for reducing the fuel ratio of a blast furnace, belonging to the technical field of blast furnace ironmaking energy conservation and efficiency improvement, and the method comprises the following steps: drawing a Richter operating line of the blast furnace to be optimized according to production data of furnace charge components, operating parameters, molten iron components, slag components and top gas components of the blast furnace to be optimized; obtaining a Reed calculation formula according to a Reed operating line; obtaining a relational expression of the direct reduction degree and the blast furnace operation index according to a Richter calculation formula; drawing a relation graph of each blast furnace production index and the direct reduction degree according to a relation between the direct reduction degree and the blast furnace operation index, wherein the blast furnace production index comprises a coal gas utilization rate index, a ton iron air quantity index, an oxygen enrichment rate index and a furnace entering taste index; determining the blast furnace production index to be optimized according to the relation graph of each blast furnace production index and the direct reduction degree; improving the blast furnace operation system according to the blast furnace production index to be optimized; the fuel ratio of the blast furnace is effectively and quickly reduced.
Description
Technical Field
The invention belongs to the technical field of blast furnace ironmaking energy conservation and efficiency improvement, and particularly relates to a method for reducing the fuel ratio of a blast furnace.
Background
The steel industry is a powerful support for national economy, and products of the steel industry are seen everywhere in various industries and play an important role in national construction. Blast furnace iron making is used as a core link in the whole iron making system, and the stability of various economic and technical indexes of the blast furnace is the key point for controlling the iron making cost and benefit. Nowadays, the economic development of China enters a new normal state, the problems of energy consumption and environmental pollution brought by the steel industry are also greatly concerned, and the blast furnace ironmaking process accounts for 70% of the total energy consumption of steel. Therefore, the iron-making process is the key point of energy conservation and emission reduction in the iron and steel industry, and the energy conservation and emission reduction potential of the blast furnace process should be fully exploited. In order to respond to the national call of energy conservation and emission reduction and environmental protection, many ironmaking enterprises start from the source, and the fuel ratio of a blast furnace is reduced, so that ultralow emission and green production of an ironmaking process are realized. The fuel ratio is an important indicator of the degree of coalification, and the higher the value, the greater the energy consumption amount. In incomplete statistics of 2018, the fuel ratio of 917 blast furnaces was lower than 500kg/t in only 22 blast furnaces. The fuel ratio of most blast furnaces is caused by high smelting intensity, large air quantity and high utilization coefficient, and the fuel ratio is also high due to low grade of iron fed into the furnace and low temperature of hot air, and the pollutant emission is also high. The average fuel ratio of the blast furnace in China is 545kg/t, the highest fuel ratio reaches 593.91kg/t, and the foreign advanced level is less than 500 kg/t. Analysis shows that foreign blast furnace low fuel ratio benefits from higher grade of charged iron, low utilization coefficient, most of furnace materials are pellet ore, and high utilization coefficient and high yield are not pursued. Although the iron smelting technology in China enters the advanced world ranks, the fuel ratio of a blast furnace has a certain difference with the world leading level. Researches show that 78% of heat required by blast furnace ironmaking comes from combustion of carbon, and the fuel ratio in blast furnace ironmaking cost accounts for 25-30%, so that the reduction of the fuel ratio of the blast furnace is particularly important for reducing the production cost and improving the market competitiveness.
Disclosure of Invention
In view of the above, the present invention has been developed to provide a method of reducing the blast furnace fuel ratio that overcomes, or at least partially addresses, the above-mentioned problems.
An embodiment of the present invention provides a method for reducing a fuel ratio of a blast furnace, including:
drawing a Richter operating line of the blast furnace to be optimized according to production data of furnace charge components, operating parameters, molten iron components, slag components and top gas components of the blast furnace to be optimized;
obtaining a Reed calculation formula according to the Reed operating line;
obtaining a relational expression of the direct reduction degree and the blast furnace operation index according to the Richter calculation formula;
drawing a relation graph of each blast furnace production index and the direct reduction degree according to the relation between the direct reduction degree and the blast furnace operation index, wherein the blast furnace production index comprises a coal gas utilization rate index, a ton iron air quantity index, an oxygen enrichment rate index and a furnace entering taste index;
determining the blast furnace production index to be optimized according to the relation graph of each blast furnace production index and the direct reduction degree;
and improving the operation system of the blast furnace according to the production index of the blast furnace to be optimized so as to reduce the direct reduction degree and further realize the reduction of the fuel ratio of the blast furnace.
Optionally, in the relational expression between the direct reduction degree and the blast furnace operation index obtained according to the rister calculation formula, the relational expression between the direct reduction degree and the blast furnace operation index is as follows:
wherein, γdRefers to the degree of direct reduction; w (FeO) means the FeO content in the charge; w (TFe) refers to the integrated charge grade of the charge; vbThe air quantity consumed by smelting 1 ton of molten iron is the air quantity consumed by one ton of iron; woMeans oxygen enrichment in the blastPercent increase in oxygen content, i.e., oxygen enrichment; w [ Fe ]]The mass fraction of iron element in the pig iron is referred to; etaCOThe utilization rate of the blast furnace gas is referred to; y isfMeans that 1mol of Fe is produced from SiO2、MnO、P2O5And the number of moles of desulfurized oxygen deprived.
Optionally, in the relation between the direct reduction degree and the blast furnace operation index, YfThe calculation formula is as follows:
wherein, W [ Si ] refers to the mass fraction of silicon element in the pig iron; w [ Mn ] refers to the mass fraction of manganese element in the pig iron; w [ P ] is the mass fraction of phosphorus element in the pig iron; w (S) refers to the mass fraction of sulfur element in the slag; w [ Fe ] refers to the mass fraction of iron element in the pig iron; u refers to the slag discharge amount of ton iron, namely the slag-iron ratio.
Optionally, the drawing a lister operating line of the blast furnace to be optimized according to production data of furnace charge components, operating parameters, molten iron components, slag components and top gas components of the blast furnace to be optimized specifically includes:
obtaining the data of oxygen amount deprived by reduction of iron oxide, oxygen amount deprived by reduction of a small amount of elements, oxygen amount deprived by oxidation of carbon in front of a tuyere and carbon-oxygen atom ratio according to production data of furnace charge components, operating parameters, molten iron components, slag components and furnace top gas components of a blast furnace to be optimized;
and drawing a Richter operating line of the blast furnace to be optimized according to the oxygen amount deprived by the reduction of the iron oxide, the oxygen amount deprived by the reduction of a small amount of elements, the oxygen amount deprived by the oxidation of carbon in front of a tuyere and the data of the carbon-oxygen atom ratio.
Optionally, the drawing a relational graph between each blast furnace production index and the direct reduction degree according to the relational expression between the direct reduction degree and the blast furnace operation index specifically includes:
and analyzing the influence of the quality of raw fuel and operating parameters on the direct reduction degree of the iron-making blast furnace to be optimized by combining the indexes of the blast furnace to be optimized according to the relational expression of the direct reduction degree and the blast furnace operating indexes, and then drawing a relational graph of each blast furnace production index and the direct reduction degree under the condition of ensuring that the quality of the components of the iron slag product is unchanged.
Optionally, the method further includes:
determining the production index of the blast furnace to be optimized again according to the production data of the furnace burden component, the operation parameter, the molten iron component, the slag component and the top gas component of the blast furnace to be optimized, which improve the operation system of the blast furnace;
and improving the blast furnace operation system according to the determined blast furnace production index to be optimized.
Based on the same inventive concept, the embodiment of the present invention also provides a method for reducing the fuel ratio of a blast furnace, the method comprising: the blast furnace fuel ratio is reduced by reducing the carbon consumption.
Optionally, the method includes: the carbon consumption is reduced by reducing the degree of direct reduction, thereby reducing the blast furnace fuel ratio.
Optionally, the method includes: the carbon consumption is reduced by reducing the oxygen enrichment rate, thereby reducing the fuel ratio of the blast furnace.
Optionally, the method includes: the carbon consumption is reduced by reducing the blast humidity, thereby reducing the blast furnace fuel ratio.
One or more technical solutions in the embodiments of the present invention have at least the following technical effects or advantages:
the method for reducing the fuel ratio of the blast furnace provided by the embodiment of the invention comprises the following steps: drawing a Richter operating line of the blast furnace to be optimized according to production data of furnace charge components, operating parameters, molten iron components, slag components and top gas components of the blast furnace to be optimized; obtaining a Reed calculation formula according to the Reed operating line; obtaining a relational expression of the direct reduction degree and the blast furnace operation index according to the Richter calculation formula; drawing a relation graph of each blast furnace production index and the direct reduction degree according to the relation between the direct reduction degree and the blast furnace operation index, wherein the blast furnace production index comprises a coal gas utilization rate index, a ton iron air quantity index, an oxygen enrichment rate index and a furnace entering taste index; determining the blast furnace production index to be optimized according to the relation graph of each blast furnace production index and the direct reduction degree; improving the operation system of the blast furnace according to the production index of the blast furnace to be optimized so as to reduce the direct reduction degree and further realize the reduction of the fuel ratio of the blast furnace; based on the carbon consumption essence of blast furnace smelting, the influence factors of the direct reduction degree are analyzed, and the fuel ratio reducing way of the blast furnace is determined by combining the problems of the blast furnace, so that the fuel ratio of the blast furnace is effectively and quickly reduced.
The above description is only an overview of the technical solutions of the present invention, and the embodiments of the present invention are described below in order to make the technical means of the present invention more clearly understood and to make the above and other objects, features, and advantages of the present invention more clearly understandable.
Drawings
In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on the drawings without creative efforts.
FIG. 1 is a graph of experimental blast furnace Richter operating line provided by an embodiment of the invention;
FIG. 2 is a quantitative relationship diagram between the utilization rate of the experimental blast furnace gas and the degree of direct reduction provided by the embodiment of the invention;
FIG. 3 is a graph showing the quantitative relationship between the ton iron air quantity and the direct reduction degree of the experimental blast furnace provided in the embodiment of the present invention;
FIG. 4 is a graph showing the quantitative relationship between the oxygen enrichment rate and the degree of direct reduction of an experimental blast furnace provided by an embodiment of the present invention;
FIG. 5 is a graph showing the quantitative relationship between the quality of the blast furnace and the degree of direct reduction according to the present invention;
FIG. 6 is a graph showing the relationship between the gas utilization rate and the furnace temperature of an experimental blast furnace provided by an embodiment of the present invention in a month;
FIG. 7 is a graph of gas utilization versus slag basicity for a month of an experimental blast furnace provided in an example of the present invention;
FIG. 8 is a graph of the temperature of the top of an experimental blast furnace at a month according to an embodiment of the present invention;
FIG. 9 is a graph of experimental blast furnace gas utilization and fuel ratio provided by an embodiment of the present invention;
FIG. 10 is a graph showing the relationship between the degree of direct reduction of an experimental blast furnace and the utilization rate of coal gas according to an embodiment of the present invention;
fig. 11 is a flow chart of a method provided by an embodiment of the invention.
Detailed Description
The present invention will be described in detail below with reference to specific embodiments and examples, and the advantages and various effects of the present invention will be more clearly apparent therefrom. It will be understood by those skilled in the art that these specific embodiments and examples are provided to illustrate the invention, and not to limit the invention.
Throughout the specification, unless otherwise specifically noted, terms used herein should be understood as having meanings as commonly used in the art. Accordingly, unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. If there is a conflict, the present specification will control.
Unless otherwise specifically stated, various raw materials, reagents, instruments, equipment and the like used in the present invention are commercially available or can be prepared by an existing method.
In order to solve the technical problems, the general idea of the embodiment of the application is as follows:
the applicant finds in the course of the invention that: the essence of improving the blast furnace fuel ratio index is to control the carbon consumption in the blast furnace, and the carbon consumption in the blast furnace iron making process mainly comprises three aspects, namely direct reduction consumption, tuyere front combustion consumption and molten iron carburizing consumption, and the total carbon consumption required for smelting ton of iron can be determined by the following formula:
F＝Cdirect connection+CTuyere+CCarburizing (1)
In the formula CDirect connection-the amount of carbon consumed per ton of pig iron by direct reduction, kg;
CtuyereThe amount of carbon blown and combusted in front of a tuyere of each ton of pig iron is kg;
Ccarburizing-the carburization quantity per ton pig iron, kg;
the carbon consumption in the above formula is obtained by carbon balance in the blast furnace, and the carbon consumption in the direct reduction can be divided into two parts:
Cdirect connection＝CdFe+Cd others (2)
In the formula, CdFeIt means the carbon amount, kg, consumed by directly reducing FeO; cd othersIs CO separated from other elements such as Si, Mn, P and the like and limestone at a high temperature2The amount of carbon consumed by the reduction, kg. When no waste iron is added into the blast furnace, the direct reduction of iron consumes carbon CdFeCan be expressed as:
wherein [ Fe ]]Means the mass percentage content of iron element in the molten iron, gammadThe degree of direct reduction defined for Barplov, i.e., the ratio of the amount of direct reduced iron obtained by blast furnace smelting to the total amount of iron. Direct reduction of other elements in pig iron and pyrolysis of CO from limestone2Amount of carbon C consumed by meltingd othersCan be calculated from the following equation.
Wherein [ Si ]]、[Mn]、[P]Are the mass percentage of the corresponding elements in the pig iron respectively; omegaLimeThe dosage of limestone per ton of pig iron is unit kg;
for CO in lime2Content (c); alpha is the decomposition rate of limestone in high temperature zone, and is generally 0.4 to0.6, and when calculated, may be equal to 0.5.
The amount of carbon burned in front of the tuyere depends on the oxygen concentration in the blast air when the blast air humidity is wHOxygen enrichment rate of wOThe oxygen concentration in the blast air was:
φO2＝0.21+0.29wH+wo (5)
according to the combustion reaction of carbon 2C + O2→ 2CO, calculate CTuyereComprises the following steps:
in the formula, VbM is the air consumption per ton of iron3。
Under certain smelting conditions, the molten iron has stable components, and A, B constants can be set as follows:
A＝2.143[Fe] (7)
when the smelting conditions are determined, the dosage of limestone is certain, and the total consumption F of iron and carbon of each smelting ton can be represented by the following general formula:
F＝A·γd+B+1.071×(0.21+0.29wH+wO)Vb (9)
and the heat balance calculation shows the air volume V of the iron drum per tonbAnd degree of direct reduction gammadSubstantially proportional straight-line relationship, i.e. Vb＝m·γd+ n, with γdIncrease the blast volume V per unit pig ironbIs also increased. And then the formula is arranged to obtain:
F＝A·γd+B+1.071×(0.21+0.29wH+wO)·(m·γd+n) (10)
in conclusion, it can be seen that the total carbon consumption of the pig iron smelted by the blast furnace is respectively influenced by the direct reduction degree, the oxygen enrichment rate and the blast humidity degree, and the direct reduction degree of the iron smelting is dominant, so that the control of the direct reduction degree of the iron smelting by the blast furnace is of great significance for reducing the fuel consumption of the blast furnace.
According to an exemplary embodiment of the present invention, there is provided a method for decreasing a fuel ratio of a blast furnace, which analyzes an influence factor of a degree of direct reduction through a theoretical calculation of the degree of direct reduction, and determines a fuel ratio decreasing route of the blast furnace in conjunction with a problem of the blast furnace itself, the method including the steps of:
s1: drawing a list operating line of the blast furnace according to production data such as furnace burden components, operating parameters, molten iron components, slag components, furnace top gas components and the like of the blast furnace to be optimized;
s2: the general relation between the direct reduction degree and the blast furnace operation index is derived based on a Richter calculation formula as follows:
s3: combining the actual working condition of the blast furnace to be optimized and the feasibility of measures to reduce the direct reduction degree as a core thinking, selecting a reasonable optimization index, and improving the operation system of the blast furnace based on the index;
s4: after improvement measures are implemented, the operation is carried out for a period of time for rechecking, and the conditions of theoretical change values and actual change values of indexes influencing the direct reduction degree are quantitatively compared, and then main indexes influencing the direct reduction degree are analyzed;
s5: after the main indexes are determined, in the subsequent optimization practice, the limitation on the indexes of the non-dominant factors can be relaxed, and greater production benefits are pursued.
The research is based on the carbon consumption essence of blast furnace smelting, analyzes the influence factors of the direct reduction degree, combines the problems of the blast furnace, and further determines the way of reducing the fuel ratio of the blast furnace, thereby being an important breakthrough for applying theory to practice.
The analysis method is provided with a cycle optimization link combining implementation and reexamination, and by quantitatively comparing the conditions of the theoretical change value and the actual change value of the indexes influencing the direct reduction degree and analyzing the main indexes influencing the direct reduction degree, the conclusion can be more consistent with the blast furnace practice finally, and the fuel condition of the blast furnace can be more accurately improved.
The method for reducing the blast furnace fuel ratio of the present application will be described in detail with reference to examples and experimental data.
Example 1
The experimental blast furnace of a certain domestic enterprise is formally opened in 2010, and the volume of the blast furnace is 4000m3. During production operation, problems of low furnace top pressure, low gas utilization rate, poor furnace hearth activity and the like often occur in the experimental blast furnace, meanwhile, the fuel ratio index is always high, and the statistical result of the production index in the last half year in 2019 shows that the average ton iron fuel ratio of the experimental blast furnace is up to 511.85 kg. A lister operation line of the experimental blast furnace was drawn based on production data of the burden composition, the production index, the molten iron composition, the slag composition, the top gas composition, and the like of the experimental blast furnace of a certain enterprise in 7 months in 2019, which are listed in tables 1 to 5, as shown in fig. 1.
TABLE 1 blast furnace raw Fuel composition in wt%
TABLE 2 blast furnace operating parameters
TABLE 3 composition of molten iron, wt%
TABLE 4 slag composition, wt.%
TABLE 5 blast furnace top gas composition%
1) Oxygen amount of iron oxide reduction and abstraction
The mineral in which iron oxides may be present in the iron-containing material is Fe2O3FeO, then:
2) minor elements reduce the oxygen abstracted:
the number of oxygen atoms abstracted during the reduction and desulfurization of the minor elements is the same as the number of carbon atoms consumed, then:
3) oxygen amount captured by oxidation of C in front of tuyere:
the carbon burning in front of the tuyere is that one C atom and one oxygen atom are combined into CO, and the air consumption per ton of iron is as follows:
Vt＝1244.20m3/t (13)
oxygen amount contained in blast air:
the chemical reaction that takes place in the combustion of the carbon in front of the tuyere is as follows:
2C+O2＝2CO (15)
then:
4) oxygen to carbon atomic ratio n (O)/n (C)
The oxygen-carbon atomic ratio in the coal gas can be directly calculated according to the coal gas components, and then:
the rister operating curve for the current operating conditions is plotted as shown in fig. 1.
The experimental blast furnace rister operating line equation is obtained in conclusion:
y＝2.124x-1.6426 (18)
the direct reduction degree is:
rd＝0.482 (19)
substituting the calculated experimental blast furnace direct reduction degree and the related index parameters into a carbon consumption calculation formula to obtain:
A＝2.143[Fe]＝202.73 (20)
F＝202.73·γd+408.841＝508.966 (22)
according to the calculation result, the ton iron carbon consumption of the experimental blast furnace in 2019 in 7 months is 508.966kg/t, the actual average fuel ratio in 7 months is 516.89kg/t, factors such as fuel component quality are considered, the calculation result is considered to be in a reasonable range, and the calculated experimental blast furnace operation line can reflect the real smelting condition of the blast furnace to a certain extent.
According to the Rister calculation formula, the general formula of the relationship between the quantitative direct reduction degree and the blast furnace operation index is as follows:
and calculating and analyzing the influence of factors such as the quality of the raw fuel, the operating parameters and the like on the direct reduction degree of the iron smelting of the experimental blast furnace by combining the index condition of the experimental blast furnace. Under the condition of ensuring that the quality of the components of the slag iron product is not changed, a direct reduction degree and production parameter relation graph is drawn, as shown in figures 2-5.
The calculation result shows that different parameters have different influence degrees on the direct reduction degree of iron making. When the requirement on the quality of molten iron is ensured to be certain and only a single production parameter can be changed, if the direct reduction degree of 5 percent is reduced (the fuel ratio is reduced by 10.14 kg), the utilization rate of coal gas needs to be improved by about 3.5 percent; or increasing the air quantity of iron drum per ton by 125Nm3T; or the oxygen enrichment rate is improved by 3 percent; or reducing the furnace feeding grade of the mixed ore by 38 percent. Obviously, the measure of reducing the furnace inlet grade of the mixed ore by 38 percent is unreasonable and can be directly eliminated. And 6, making statistics on the average utilization rate of the blast furnace in the last ten years of 2019.
TABLE 62019 Experimental blast furnace gas utilization
As can be seen from the table, the lowest value of the utilization rate of the 3# blast furnace gas is 44.69%, the highest value is 46.28%, not only has a certain difference from the best level of the industry, but also the process control fluctuation is large.
Therefore, from the perspective of actual production cost, by combining specific working conditions such as low gas utilization rate of the experimental blast furnace, low top pressure and the like and the feasibility of measures, the method takes the improvement of the gas utilization rate as a core idea, is suitable for the current experimental blast furnace state, and further effectively achieves the aim of reducing the fuel ratio of the experimental blast furnace.
(1) Hearth state improvement measure
The macroscopic reasons influencing the gas utilization rate have two aspects: the contact time of the furnace burden and the coal gas flow and the reaction time of the furnace burden and the coal gas flow. Comparing the blast furnace temperature alkalinity and the gas utilization rate in the experiment of 7 months in 2019, as shown in fig. 6 and 7, the data comparison shows that the gas utilization rate is relatively low in the area with large index fluctuation, and the gas utilization rate is increased when the thermal state of the furnace hearth is good. Therefore, experimental enterprises adopt methods of improving blast kinetic energy, reducing the hypertrophy of dead material columns and improving the activity of the hearth. In addition, for a double-taphole blast furnace, the taphole tapping rate must reach more than 73 percent to meet the requirement of blast furnace slag iron discharge. The activity of the blast furnace hearth is not strong, the iron outlet iron yield of the iron notch is low, the discharge of blast furnace slag iron is not smooth, the slag iron holding operation of the blast furnace is caused, and the coal gas flow distribution is disordered. Therefore, the 3# blast furnace taphole is maintained in time, the tapping frequency is stabilized to 8-10 times/d, and the stable balance between the tapping quantity and the slag iron generation quantity is ensured so as to maintain the stable slag iron liquid level.
(2) The cloth system has problems and improvements
From the results of the cross temperature measurement of the furnace top, as shown in fig. 8, the flatness of the charge level of the furnace top is not sufficient, the central gas flow is excessively developed, the central passage is excessively wide and uneven, a large amount of gas escapes from the central passage to the furnace top, the edge gas flow is not correspondingly developed, the contact time between the charge and the gas flow is greatly reduced, and the gas utilization rate is greatly reduced. The experimental blast furnace changes the batch weight of the ore and increases the number of ore distribution turns between the furnace wall and the center; meanwhile, the coke distribution width is increased from 36.5-15 degrees to 37-14.5 degrees, and the coke load at the center and the edge is optimized.
(3) Raw material index is problematic and improved
The results of the particle size analysis of the uniform charging materials in 2019 are shown in the following table. The proportion of the grain diameter of the charging material of the experimental blast furnace is lower than 5mm, the average grain size of the used coke is only 50mm, the small grain sizes of the mineral material and the coke can cause poor air permeability of a material column, influence the reasonable and stable distribution of air flow, lead to the adverse effects of furnace condition stability and smoothness such as accumulation of a furnace cylinder and the like in severe cases, and influence the reasonable contact of the gas flow and the furnace charge, thereby influencing the utilization rate of the blast furnace gas.
TABLE 72019 Experimental blast furnace gas utilization%
In the aspect of improvement measures for charging raw materials, the experimental blast furnace adopts measures for reducing charged furnace powder, and simultaneously improves the average particle size of the furnace powder, so that the air permeability of the furnace material is ensured, the contact area of the furnace material and coal gas is increased, favorable reaction kinetic conditions are provided for indirect reduction reaction, and the utilization efficiency of the coal gas is improved.
In the practical process, the experimental blast furnace gas utilization rate is improved, and the gas utilization rate is actually improved by 1.93 percent within one year. The highest month of the gas utilization rate is 2020 and 5 months, the gas utilization rate index is 48.41%, the gas utilization rate index is increased by 2.43% compared with 7 months in 2019, the corresponding fuel ratio is reduced by 9.3kg/t, and the gas utilization rate is increased by about 1% and the fuel ratio is reduced by 3.8 kg/t.
Detailed description of the drawings 6-10:
FIG. 6 is a graph showing the relationship between the coal gas utilization rate in 7 months in 2019 and the furnace temperature of an experimental blast furnace, FIG. 7 is a graph showing the relationship between the coal gas utilization rate in 7 months in 2019 and the slag basicity of the experimental blast furnace, which can be obtained from the graphs and the graphs, the coal gas utilization rate is correspondingly low in the area with large furnace temperature and slag basicity index fluctuations, and the coal gas utilization rate is increased when the thermal state of a furnace hearth is good;
fig. 8 is a graph of the temperature measurement of the furnace top of the experimental blast furnace 2019 in 7 months, which can be obtained from the graph, the flatness of the material surface of the furnace top is not enough, the central gas flow is excessively developed, the central passage is excessively wide and uneven, a large amount of coal gas escapes from the central passage to the furnace top, the edge gas flow is not correspondingly developed, the contact time of the furnace charge and the coal gas flow is greatly reduced, and the coal gas utilization rate is greatly reduced;
FIG. 9 is a graph of gas utilization versus fuel ratio for an experimental blast furnace showing a significant correlation between gas utilization and fuel ratio, as opposed to a time curve characteristic of gas utilization versus fuel ratio, consistent with theoretical inferences;
FIG. 10 is a graph of the relationship between the degree of direct reduction of the experimental blast furnace calculated from actual production parameters of an enterprise and the utilization rate of gas, and it can be obtained from the graph that the actual degree of direct reduction of the experimental blast furnace is reduced from 48.18% to 46.48% one year ago, and the total reduction is 1.69%.
One or more technical solutions in the embodiments of the present invention at least have the following technical effects or advantages:
(1) the applicant finds in the course of the invention that: the total carbon consumption of the pig iron smelted by the blast furnace is respectively influenced by the direct reduction degree, the oxygen enrichment rate and the blast humidity, so that the carbon consumption can be controlled by controlling the factors such as the direct reduction degree, the oxygen enrichment rate, the blast humidity and the like, the fuel ratio of the blast furnace is further controlled, and the direct reduction degree of iron smelting is found to be dominant, so that the fuel ratio of the blast furnace can be more efficiently controlled by controlling the direct reduction degree;
(2) the method provided by the embodiment of the invention is based on the carbon consumption essence of blast furnace smelting, analyzes the influence factors of the direct reduction degree, combines the problems of the blast furnace, and further determines the fuel ratio reduction way of the blast furnace, thereby being an important breakthrough for applying theory to practice;
(3) the method provided by the embodiment of the invention is provided with a cycle optimization link combining implementation and reexamination, and by quantitatively comparing the conditions of the theoretical change value and the actual change value of the direct reduction degree index and analyzing the main index influencing the direct reduction degree, the conclusion can be more consistent with the blast furnace practice, and the fuel condition of the blast furnace can be more accurately improved.
Finally, it is also to be noted that the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.
While preferred embodiments of the present invention have been described, additional variations and modifications in those embodiments may occur to those skilled in the art once they learn of the basic inventive concepts. Therefore, it is intended that the appended claims be interpreted as including preferred embodiments and all such alterations and modifications as fall within the scope of the invention.
It will be apparent to those skilled in the art that various changes and modifications may be made in the present invention without departing from the spirit and scope of the invention. Thus, if such modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include such modifications and variations.
Claims (10)
1. A method of reducing the fuel ratio of a blast furnace, the method comprising:
drawing a Richter operating line of the blast furnace to be optimized according to production data of furnace charge components, operating parameters, molten iron components, slag components and top gas components of the blast furnace to be optimized;
obtaining a Reed calculation formula according to the Reed operating line;
obtaining a relational expression of the direct reduction degree and the blast furnace operation index according to the Richter calculation formula;
drawing a relation graph of each blast furnace production index and the direct reduction degree according to the relation between the direct reduction degree and the blast furnace operation index, wherein the blast furnace production index comprises a coal gas utilization rate index, a ton iron air quantity index, an oxygen enrichment rate index and a furnace entering taste index;
determining the blast furnace production index to be optimized according to the relation graph of each blast furnace production index and the direct reduction degree;
and improving the operation system of the blast furnace according to the production index of the blast furnace to be optimized so as to reduce the direct reduction degree and further realize the reduction of the fuel ratio of the blast furnace.
2. The method of reducing a fuel ratio of a blast furnace as set forth in claim 1, wherein said obtaining a direct reduction degree and a blast furnace operation index according to said rister calculation formula has a relationship as follows:
wherein, γdRefers to the degree of direct reduction; w: (W:)FeO) refers to the content of FeO in the furnace burden; w (TFe) refers to the comprehensive charge grade of the furnace burden; vbThe air quantity consumed by smelting 1 ton of molten iron is the air quantity consumed by one ton of iron; woThe oxygen enrichment rate is the percentage of the oxygen content increase in the blast air; w [ Fe ]]The mass fraction of iron element in the pig iron is referred to; etaCOThe utilization rate of blast furnace gas is indicated; y isfMeans that 1mol of Fe is produced from SiO2、MnO、P2O5And the number of moles of desulfurized oxygen deprived.
3. The method of claim 2, wherein Y is the direct reduction degree and the blast furnace operation indexfThe calculation formula is as follows:
wherein, W [ Si ] refers to the mass fraction of silicon element in the pig iron; w [ Mn ] refers to the mass fraction of manganese element in the pig iron; w [ P ] is the mass fraction of phosphorus element in the pig iron; w (S) refers to the mass fraction of sulfur element in the slag; w [ Fe ] refers to the mass fraction of iron element in the pig iron; u refers to the slag discharge amount of ton iron, namely the slag-iron ratio.
4. The method of claim 1, wherein the step of drawing the rister operating line of the blast furnace to be optimized according to the production data of the charge composition, the operating parameters, the molten iron composition, the slag composition and the top gas composition of the blast furnace to be optimized comprises:
obtaining the data of oxygen amount deprived by reduction of iron oxide, oxygen amount deprived by reduction of a small amount of elements, oxygen amount deprived by oxidation of carbon in front of a tuyere and carbon-oxygen atom ratio according to production data of furnace charge components, operating parameters, molten iron components, slag components and furnace top gas components of a blast furnace to be optimized;
and drawing a Richter operating line of the blast furnace to be optimized according to the oxygen amount deprived by the reduction of the iron oxide, the oxygen amount deprived by the reduction of a small amount of elements, the oxygen amount deprived by the oxidation of carbon in front of a tuyere and the data of the carbon-oxygen atom ratio.
5. The method for reducing the fuel ratio of the blast furnace as claimed in claim 1, wherein the step of plotting the relationship between each blast furnace production index and the direct reduction degree according to the relationship between the direct reduction degree and the blast furnace operation index comprises the following steps:
and analyzing the influence of the quality of raw fuel and operating parameters on the direct reduction degree of the iron-making blast furnace to be optimized by combining the indexes of the blast furnace to be optimized according to the relational expression of the direct reduction degree and the blast furnace operating indexes, and then drawing a relational graph of each blast furnace production index and the direct reduction degree under the condition of ensuring that the quality of the components of the iron slag product is unchanged.
6. The method of reducing a blast furnace fuel ratio of claim 1, further comprising:
determining the production index of the blast furnace to be optimized again according to the production data of the furnace burden component, the operation parameter, the molten iron component, the slag component and the top gas component of the blast furnace to be optimized, which improve the operation system of the blast furnace;
and improving the blast furnace operation system according to the determined blast furnace production index to be optimized.
7. A method of reducing the fuel ratio of a blast furnace, the method comprising: the blast furnace fuel ratio is reduced by reducing the carbon consumption.
8. The method of reducing a blast furnace fuel ratio of claim 7, comprising: the carbon consumption is reduced by reducing the degree of direct reduction, thereby reducing the blast furnace fuel ratio.
9. The method of reducing a blast furnace fuel ratio of claim 7, comprising: the carbon consumption is reduced by reducing the oxygen enrichment rate, thereby reducing the blast furnace fuel ratio.
10. The method of reducing a blast furnace fuel ratio of claim 7, comprising: the carbon consumption is reduced by reducing the blast humidity, thereby reducing the blast furnace fuel ratio.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115627306A (en) * | 2022-10-03 | 2023-01-20 | 武钢集团昆明钢铁股份有限公司 | Method for smelting low-grade and high-harmful-element material by blast furnace |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102586519A (en) * | 2012-02-24 | 2012-07-18 | 北京首钢自动化信息技术有限公司 | Calculus prediction method for adjusting operation of blast furnace |
| CN102876823A (en) * | 2012-10-24 | 2013-01-16 | 北京科技大学 | Method for computing degree of direct reduction and gas utilization rate of blast furnace under condition of high-reactivity coke |
| CN104988259A (en) * | 2015-07-25 | 2015-10-21 | 东北大学 | Method for drawing Rist operating line for blast furnace |
| JP2018024936A (en) * | 2016-08-02 | 2018-02-15 | Ｊｆｅスチール株式会社 | Molten iron temperature prediction method, molten iron temperature prediction device, operation method of blast furnace, operation guidance device, molten iron temperature control method and molten iron temperature control device |
| CN108197785A (en) * | 2017-12-20 | 2018-06-22 | 北京科技大学 | A kind of harmful element is on method for building up of the blast furnace fuel than the computational methods of influence |
-
2021
- 2021-07-29 CN CN202110865369.9A patent/CN113667781B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102586519A (en) * | 2012-02-24 | 2012-07-18 | 北京首钢自动化信息技术有限公司 | Calculus prediction method for adjusting operation of blast furnace |
| CN102876823A (en) * | 2012-10-24 | 2013-01-16 | 北京科技大学 | Method for computing degree of direct reduction and gas utilization rate of blast furnace under condition of high-reactivity coke |
| CN104988259A (en) * | 2015-07-25 | 2015-10-21 | 东北大学 | Method for drawing Rist operating line for blast furnace |
| JP2018024936A (en) * | 2016-08-02 | 2018-02-15 | Ｊｆｅスチール株式会社 | Molten iron temperature prediction method, molten iron temperature prediction device, operation method of blast furnace, operation guidance device, molten iron temperature control method and molten iron temperature control device |
| CN108197785A (en) * | 2017-12-20 | 2018-06-22 | 北京科技大学 | A kind of harmful element is on method for building up of the blast furnace fuel than the computational methods of influence |
Non-Patent Citations (1)
| Title |
|---|
| 王筱留: "中国高炉实现低碳低成本炼钢问题探讨", 《鞍钢技术》 * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115627306A (en) * | 2022-10-03 | 2023-01-20 | 武钢集团昆明钢铁股份有限公司 | Method for smelting low-grade and high-harmful-element material by blast furnace |
| CN115627306B (en) * | 2022-10-03 | 2023-11-10 | 武钢集团昆明钢铁股份有限公司 | Method for smelting low-grade high-harmful element materials by blast furnace |
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