KR101572391B1 - Method for assuming and controlling coke size in bottom part of blast furnace - Google Patents

Abstract

Disclosed is a method for assuming and controlling the size of a lower coke of a blast furnace. According to an embodiment of the present invention, the method for assuming and controlling the size of a lower coke of a blast furnace comprises: a step of deducing a warm strength and an average size of charging coke and an amount of introduced oxygen; a step of determining whether an amount of pulverized coal introduced into the blast furnace exceeds a preset value; and a step of calculating an assumed size value of the lower coke of the blast furnace in accordance with an assumption formula variable depending on whether the amount of the introduced pulverized coal exceeds the preset value. The assumption formula is equation 1 shown below in a case where the amount of the introduced pulverized coal exceeds the preset value and is equation 2 shown below in a case where the amount of the introduced pulverized coal is within the preset value. (Equation 1) MS lower part of blast furnace = -0.29 * (A/100) + 0.54 * B + 0.8 * C - 52.1. (Equation 2) MS lower part of blast furnace = -0.38 * (A/100) + 0.37 * B + 0.75 * C - 36.8 (MS lower part of blast furnace: assumed size value of lower coke of blast furnace, A: amount of introduced oxygen, B: warm strength of charging coke, and C: average size of charging coke).

Description

Technical Field [0001] The present invention relates to a method for predicting a grain size of a blast furnace bottom coke,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and a method for predicting the grain size of a blast furnace bottom coke.

The blast furnace operation is a process in which the iron ore charged in the upper part of the blast furnace is melted by the hot air supplied through the tuyeres to produce melts (molten iron and slag), and the melts accumulated in the furnace are discharged continuously through the outlet .

Coke is produced by heating the coal in a coke oven and charging it into the blast furnace. The coke acts as a heat source for melting iron ore in the blast furnace. It functions to ensure ventilation to smooth the flow of reducing gas, and discharges charcoal and slag To maintain the liquid permeability.

The background art of the present invention is disclosed in Korean Patent Laid-Open Publication No. 10-1997-0042956 (July 26, 1997, Manufacturing method of blast furnace coke).

The present invention provides a method and a method for predicting the grain size of a blast furnace bottom coke and a method for predicting and controlling the grain size of a blast furnace bottom coke.

According to an aspect of the present invention, there is provided a method for producing a coke oven, comprising the steps of: deriving a charging coke hot strength of a blast furnace, an average particle diameter of charged coke, Determining whether the amount of coal pulverized in the blast furnace exceeds a predetermined value; And calculating a predicted value of the lower-core coke oven particle diameter by varying a prediction formula depending on whether the amount of pulverized coal charged exceeds a predetermined value; Wherein the prediction formula is the following formula (1) when the amount of pulverized coal to be injected exceeds a predetermined value, and the following formula (2) when the amount of pulverized coal to be pulverized does not exceed the preset value: A prediction method is provided.

(1)

MS _{blast furnace bottom} = -0.29 * (A / 100) + 0.54 * B + 0.8 * C-52.1

(2)

MS _{blast furnace bottom} = -0.38 * (A / 100) + 0.37 * B + 0.75 * C-36.8

Is provided (MS _{furnace bottom:} average particle size blast furnace coke charged particle size of the lower coke predicted value, A: Depth of cut oxygen, B:: charging the hot coke strength, C).

According to another aspect of the present invention, there is also provided a method for producing a coke oven, Determining whether or not the predicted value of the lower coke particle diameter of the blast furnace according to the blast furnace bottom coke particle size prediction step satisfies the reference particle diameter; And adjusting the oxygen content according to whether or not the predicted value of the particle diameter of the lower coke blast satisfies the reference particle diameter; A method for controlling a grain boundary of a blast furnace lower coke is provided.

The default value may be 170 kg / THM.

The step of adjusting the oxygen content comprises the steps of maintaining the oxygen content when the predicted value of the particle diameter of the lower portion of the blast furnace satisfies the reference particle size; And changing the oxygen content to the changed oxygen content when the predicted value of the grain size of the blast furnace bottom coke does not satisfy the reference grain size.

The changed oxygen input amount can be calculated inversely by a prediction formula so as to satisfy the reference particle size.

The reference particle size may be 18 mm.

The step of changing to the changed oxygen input amount may be performed by changing the amount of air blown into the blast furnace.

The step of changing to the changed oxygen content may be performed by changing the amount of pure oxygen blown into the blast furnace.

According to the embodiment of the present invention, it is possible to predict and control the particle diameter of the bottom coke of the blast furnace.

1 schematically shows a blast furnace.
2 is a flow chart illustrating a method for predicting the grain size of a blast furnace bottom coke according to an embodiment of the present invention.
3 is a graph showing the grain size of a coke oven bottom in accordance with the oxygen amount applied to an embodiment of the present invention.
4 is a graph showing the grain size of the lower portion of the blast furnace according to the average particle diameter of charged coke applied to an embodiment of the present invention.
5 is a graph showing the grain size of the lower coke in the blast furnace according to the hot-coke hot strength applied to an embodiment of the present invention.
6 is a graph showing a correlation between a blasted lower coke particle diameter predicted value and an actual blast furnace lower coke diameter actual measured value according to Equation 1 applied to an embodiment of the present invention.
7 is a graph showing the correlation between the predicted value of the lower coke particle diameter of the blast furnace and the actually measured value of the lower coke particle diameter of the blast furnace according to the formula (2) applied to an embodiment of the present invention.
8 is a flowchart showing a method of controlling the grain size of a blast furnace bottom coke according to another embodiment of the present invention.

The terminology used in this application is used only to describe a specific embodiment and is not intended to limit the invention. The singular expressions include plural expressions unless the context clearly dictates otherwise. In the present application, the terms "comprises" or "having" and the like are used to specify that there is a feature, a number, a step, an operation, an element, a component or a combination thereof described in the specification, But do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or combinations thereof.

It is also to be understood that the terms first, second, etc. used hereinafter are merely reference numerals for distinguishing between identical or corresponding components, and the same or corresponding components are defined by terms such as first, second, no.

The term " coupling " does not mean that only a physical contact is directly made between the respective components in the contact relationship between the respective components, but a different configuration is interposed between the respective components, Use it as a concept to cover until you are in contact.

On the other hand, in the present specification, the particle diameter of the particles means an average particle diameter. Also, it should be used to refer to the vicinity of the tornado of the blast furnace.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of a method and a method for predicting a grain diameter of a blast furnace bottom coke according to the present invention will be described in detail with reference to the accompanying drawings, wherein like reference numerals designate like or corresponding components And redundant explanations thereof will be omitted.

First, the method of predicting the grain size of the blast furnace bottom coke according to one embodiment of the present invention will be described.

1 is a view schematically showing a blast furnace. FIG. 2 is a flowchart illustrating a method of predicting the grain size of a blast furnace bottom coke according to an embodiment of the present invention. FIG. 3 is a graph showing the grain size of the lower portion of the blast furnace according to the amount of oxygen applied to an embodiment of the present invention. FIG. 4 is a graph showing the grain size of the lower portion of the blast furnace according to the average particle diameter of the charged coke applied to one embodiment of the present invention. 5 is a graph showing the grain size of the lower portion of the blast furnace according to the hot-coke hot strength applied to an embodiment of the present invention. 6 is a graph showing the correlation between the predicted value of the lower coke particle diameter in the blast furnace and the actually measured value of the lower coke powder particle diameter in accordance with Equation 1 applied to the embodiment of the present invention. 7 is a graph showing the correlation between the predicted value of the lower-coke particle diameter in the blast furnace and the actually measured value of the lower-coke particle diameter in the blast furnace according to the formula (2) applied to an embodiment of the present invention.

As shown in FIG. 2, the method of predicting the grain size of the blast furnace bottom coke according to an embodiment of the present invention starts from the step S100 of deriving the blast furnace coke hot strength, the charging coke average grain size and the oxygen loading.

1, the blast furnace 10 is a facility for charging iron ore and coke from the upper part of the blast furnace 10 and producing molten iron by the hot air supplied from the tuyeres 20. The coke is a raw material used as a heat source of the blast furnace 10 and serves as a reducing agent for reducing iron ores. Coke is produced by heating coal in a coke oven.

The charging coke hot strength and the charging coke average particle diameter can be measured by measuring the state of coke charged into the blast furnace 10 from the top of the blast furnace 10 or by inserting a probe pipe into the blast furnace 10 A sample of water can be obtained by sampling from the tip of the tuyere to the core. In the latter case, it is also possible to separate the coke from the core area, separate the coke from the coke after manual separation, and analyze the data of the separated coke. Blast furnace (10) The harvesting can be carried out a plurality of times in order to increase the reliability of data in consideration of operational impact.

The amount of oxygen introduced into the blast furnace 10 (Nm ³ / min) is the total amount of oxygen (Total O ₂ ) measured from air taken in the tuyere 20 and pure oxygen. And 21% O ₂ and 79% N ₂ for air.

Next, it is determined whether or not the amount of coal pulverized in the blast furnace exceeds a predetermined value (S200). Here, the preset value may be 170 kg / THM.

The amount of pulverized coal (kg / THM) is the amount of pulverized coal to be blown into the blast furnace 10 together with hot air blown through the tuyere 20, and is the amount of pulverized coal required to produce 1 ton of charcoal.

Referring to FIGS. 3 to 5, the grain size of the lower blast furnace according to the respective parameters shows two tendencies when the blowing pulverized coal amount (PCR) exceeds 170 kg / THM. Therefore, depending on whether or not the amount of pulverized coal charged exceeds the predetermined value, the predicted value of the grain size of the lower portion of the blast furnace can be calculated by different formulas as will be described later.

On the other hand, the predetermined value may vary depending on the condition of the blast furnace, the operating conditions, and the like, which can be variously changed.

Next, the predicted value of the grain size of the lower portion of the blast furnace is calculated by varying the predictive equation depending on whether the amount of pulverized coal charged exceeds the predetermined value (S300). At this time, the predicted value is expressed by the following equation (1) when the amount of blown coal is larger than the predetermined value, and when it is not larger than the predetermined value,

(1)

MS _{blast furnace bottom} = -0.29 * (A / 100) + 0.54 * B + 0.8 * C-52.1

(2)

MS _{blast furnace bottom} = -0.38 * (A / 100) + 0.37 * B + 0.75 * C-36.8

(MS _{furnace bottom:} blast furnace coke particle size lower predictive value, A: Depth of cut of oxygen ^{(Nm 3 / min), B} : charging the hot coke strength (%), C: average particle diameter of coke charged (mm))

As described above, depending on whether or not the amount of injected pulverized coal (PCR) exceeds 170, which is the preset value, the true value of the lower coke particle diameter of the blast furnace according to each variable shows a different tendency, 2, the predicted value of the particle diameter of the lower coke of the blast furnace is calculated.

Equations (1) and (2) are derived by regression analysis with the loading coke hot strength, the average particle size of the charged coke, and the oxygen loading as independent variables.

In the conventional case, when predicting the grain size of the lower portion of the blast furnace, the charging condition (Blast Velocity) and the pulverized coal injection amount (PCR) are used as the operating conditions, and the charging coke cold strength (DI) CSR) and the average particle diameter of the charged coke. However, only the oxygen content, the charging coke hot strength, and the charging coke average particle diameter can be used as the parameters for predicting the particle diameter of the lower blast furnace according to an embodiment of the present invention.

6 and 7 are diagrams showing the correlation between the predicted value of the lower coke particle diameter and the measured value according to the formula (1) or (2).

The actual value can be obtained by inserting a probe pipe into the blast furnace bottom tuyere, collecting the sample, separating only the coke, and measuring the particle diameter.

Blowing the pulverized coal amount (PCR) The predetermined value of With reference to the Figure 6, if it exceeds 170, the blast furnace bottom coke particle size predicted and therefore the lower coke particle diameter measured value calculated by the equation (1) is the correlation coefficient R ² is 0.83 Correlation. Blowing the pulverized coal amount (PCR) The predetermined value of With reference to the Figure 7 does not exceed 170, the blast furnace bottom coke particle size predicted and therefore the lower coke particle diameter measured value calculated in equation (2) is the correlation coefficient R ² of 0.90 Correlation.

By doing so, the method of predicting the grain size of the blast furnace bottom coke according to an embodiment of the present invention facilitates the particle size of the blast furnace coke by using only the input coke hot strength and the charging coke average grain size as variables, Can be accurately predicted.

Next, a blast furnace bottom coke particle size control method according to another embodiment of the present invention will be described.

8 is a flowchart showing a method of controlling the grain size of the blast furnace bottom coke according to another embodiment of the present invention.

As shown in FIG. 8, the blast furnace bottom coke particle size control method according to another embodiment of the present invention starts from the step of predicting the blast furnace bottom coke particle size (S1000).

The step (S1000) of predicting the blast furnace bottom coke diameter is a step (S100) of deriving the charging coke hot strength, the charging coke average particle diameter and the oxygen charging amount of the blast furnace described above, ii) whether or not the amount of the pulverized coal to be blasted exceeds the predetermined value (Iii) calculating a predicted value of the lower-core coke oven particle diameter by varying the predictive equation depending on whether the amount of coal pulverized exceeds a predetermined value (S300), and thus the description thereof will be omitted.

Next, it is determined whether or not the predicted value of the lower-portion coke oven diameter in the blast furnace bottom coke particle size prediction step satisfies the reference diameter (S1100). In other words, the predicted value of the grain size of the lower portion of the blast furnace calculated by the above-described formula (1) or (2) is compared with a preset reference grain size.

Here, the reference particle size may be 18 mm. The coke can play a role of ensuring ventilation to smoothly flow the reducing gas in the blast furnace and securing the liquid permeability to smoothly discharge charcoal and slag. This can be accomplished by controlling the particle size of the coke located near the tuyeres. This is because the lower part of the blast furnace is located at a position where the reaction gas rises from the tuyeres and influences the flow of gas rising according to the state of the blast furnace, that is, the air permeability, and the particle diameter of the blast furnace bottom coke influences the liquid permeability. On the other hand, the reference grain size can be changed according to the blast furnace operation situation or the quality of the charcoal required.

Next, the oxygen content is adjusted according to whether or not the predicted value of the particle diameter of the lower portion of the blast furnace satisfies the reference particle size (S1200).

In the step S1200 of adjusting the oxygen content, if the estimated particle diameter of the lower coke in the blast furnace satisfies the reference particle size, the oxygen content can be maintained (S1210). If the reference particle size is not satisfied, the oxygen content is changed to the changed oxygen content (S1220).

As described above, the formula (1) or (2) uses the charging coke hot strength, the charging coke average particle diameter and the oxygen charging amount as variables, and the blast furnace bottom coke particle diameter control method according to another embodiment of the present invention, It is possible to control the particle diameter of the lower coke in the blast furnace.

In more detail, when the amount of injected pulverized coal (PCR) exceeds 170, the predicted value of the grain diameter of the lower blast furnace in the blast furnace is first calculated according to the equation (1). The predicted value is compared with the reference particle size. If the predicted value satisfies the reference particle size, the oxygen content is maintained. If the predicted value does not satisfy the reference particle size, the predicted value is changed to the changed oxygen content to satisfy the reference particle size.

Here, the changed oxygen content can be calculated by inverse calculation by a prediction formula so as to satisfy the reference particle size. In the above example, since the predicted value of the grain diameter of the blast furnace bottom coke was calculated by the formula (1), the changed oxygen content was calculated by inverse calculation using the formula (1).

Therefore, by more accurately determining the changed oxygen input amount, it is possible to precisely control the grain diameter of the lower blast furnace.

Changing the oxygen loading to a modified oxygen loading can be done by changing the amount of air blown into the blast furnace or changing the amount of pure oxygen. The method of changing the amount of air has an economic advantage, and the advantage of changing the amount of pure oxygen is that it can be easily changed without calculation.

Therefore, the blast furnace bottom coke particle size control method according to another embodiment of the present invention can easily control the grain size of the blast furnace bottom coke by controlling the oxygen input amount. Furthermore, it is possible to control the quality of the molten iron produced in the blast furnace.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit of the invention as set forth in the appended claims. The present invention can be variously modified and changed by those skilled in the art, and it is also within the scope of the present invention.

10: blast furnace
20: Tungus

Claims (8)

Deriving the charging coke hot strength of the blast furnace, the average particle diameter of charged coke, and the oxygen loading;
Determining whether the amount of blown coal in the blast furnace exceeds a predetermined value; And
Calculating a predicted value of the lowered-coke particle diameter of the blast furnace by varying a predictive equation depending on whether the amount of blown coal is exceeding the preset value;
Lt; / RTI >
The predictive equation,
Wherein when the amount of the pulverized pulverized coal exceeds the predetermined value, the following formula (1) is satisfied, and when the amount of pulverized pulverized coal does not exceed the predetermined value, the following formula (2) .
(1)
MS _{blast furnace bottom} = -0.29 * (A / 100) + 0.54 * B + 0.8 * C-52.1
(2)
MS _{blast furnace bottom} = -0.38 * (A / 100) + 0.37 * B + 0.75 * C-36.8
(MS _{furnace bottom:} blast furnace coke particle size lower predictive value, A: Depth of cut oxygen, B: charging the hot coke strength, C: average particle size of the coke charged)
The method according to claim 1,
Wherein the predetermined value is 170 kg / THM.
A blast furnace bottom coke particle size prediction step according to claim 1 or 2;
Determining whether or not the predicted value of the lower coke particle diameter of the blast furnace according to the step of predicting the blast furnace lower coke particle size satisfies the reference particle diameter; And
Adjusting the oxygen content according to whether the blast furnace bottom coke particle size predicted value satisfies the reference particle size;
Wherein the lower coke particle diameter control method comprises the steps of:
The method of claim 3,
The method of claim 1,
Maintaining the oxygen content when the predicted value of the lower coke bloom of the blast furnace satisfies the reference particle size; And
And changing the oxygen content to a changed oxygen content when the predicted value of the lower coke oven particle diameter does not satisfy the reference particle diameter.
5. The method of claim 4,
The modified oxygen content may be,
And the calculated value is inversely calculated by the predictive equation so as to satisfy the reference particle size.
The method of claim 3,
Wherein the reference grain size is 18 mm.
5. The method of claim 4,
The step of changing to the modified oxygen loading comprises:
And changing the amount of air blown into the blast furnace.
5. The method of claim 4,
The step of changing to the modified oxygen loading comprises:
And changing the amount of pure oxygen introduced into the blast furnace.

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