KR100805712B1 - Method for regulating the temperature of furnace using the character of coal itself - Google Patents

Abstract

More particularly, the present invention relates to a method of controlling the blast furnace according to the characteristics of pulverized coal, and more particularly, to a method for controlling pulverized coal, The present invention relates to a method of controlling the furnace for controlling the furnace according to the characteristics of the pulverized coal, which is capable of stable control of the furnace temperature by preventing the temperature inside the furnace from changing abruptly according to the exothermic characteristics of the furnace.

A method for controlling a temperature according to the present invention comprises a first step of constructing and storing a data table according to each characteristic of a call; The total inventory amount of the pulverized coal stored in the pre-change coal tank 10, the PCI call storage tank 20, the differential storage tank 50, and the feed tank 60 at the time of adjusting the PCI call type and the mixing ratio is calculated, A second step of calculating a time at which the stock amount can be taken in by the pulverized coal intake variation amount; A third step of setting a pulverized coal blowing start time after the change using the pulverized coal blowing time of the pre-change call calculated in the second step; A fourth step of calculating a deviation heat generation amount before and after the change according to the PCI call type and the composition ratio change; And a fifth step of resetting the amount of pulverized coal injected after the change of the type of call and the blending ratio by the amount of heat generated by the deviation, and blowing it into the blast furnace 1.

Blast furnace, non-coal, coal, coal, coke, semi-anthracite

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for controlling a furnace,

1 is a schematic diagram of a conventional PCI manufacturing and blowing facility,

FIG. 2 is a diagram showing the types and characteristics data of calls classified according to the present invention,

3 is a schematic diagram of a manufacturing and blowing facility in which the method of the present invention is performed,

4 is a block diagram for calculating the pulverized coal and calculating the blowing time of the present invention,

5 and 6 are graphs showing the set state of the pulverized coal blowing time,

FIG. 7 is a block diagram for calculating the deviation heat amount and determining the amount of intake of the present invention,

Figs. 8 and 9 are graphs showing a blowing amount when changing to a high heat amount and a low heat amount.

[Description of Reference Numerals]

1: blast furnace 2: tungsten

3: Pulverized coal blowing lance 4: Nitrogen compressor

10: Shipbuilding storage tank 10A: (Shipbuilding storage tank) Weight detector

11,21: Weighing machine 15: Belt conveyor

20: PCI call reservoir 20A: (PCI call reservoir) weight detector

25: Cole feeder 30: Mill

35: Outlet line 40: Bag filter                 

50: Differential storage tank 50A: (Differential storage tank) weight detector

60; Feed Tank 60A: (Feed Tank) Weight Detector

65: pick-up 70:

80: Pulverized coal blowing controller 90: Shipbuilding process computer

100: Process computer 200: Host controller

300: blast furnace computer

More particularly, the present invention relates to a method of controlling the blast furnace according to the characteristics of pulverized coal, and more particularly, to a method for controlling pulverized coal, The present invention relates to a method of controlling the furnace for controlling the furnace according to the characteristics of the pulverized coal, which is capable of stable control of the furnace temperature by preventing the temperature inside the furnace from changing abruptly according to the exothermic characteristics of the furnace.

In the blast furnace operation at the steelworks, a large amount of pulverized coal, which is an alternative raw material of coke, is blown and used. The purpose of injecting pulverized coal is to solve the environmental pollution problem caused by the manufacturing process of the coke, and also to be able to exhibit the same heat quantity at a lower cost than the coke. The purchase price per ton of coke is about 100,000 won, and the purchase price per ton of coal, which is the raw material of pulverized coal, is about 40,000-70,000 won. Therefore, when a low cost call is used in a blast furnace in a large amount, it is very effective in cost reduction.

For example, the amount of coke required to produce 1 ton of charcoal is 485 kg / TP in the blast furnace by charging coke and iron ore into the blast furnace at the blast furnace, / TP + tinning coal 135kg / TP), it is possible to reduce environmental pollution by suppressing the usage amount of coke. In addition, there is a tendency to mix various kinds of coke in recent years because not only the tin-coke but also the tin-coke or semi-anthracite are mixed at the same time to reduce the coke use amount and cost reduction effect.

First, referring to FIG. 1, a process for using pulverized coal in the conventional blast furnace 1 will be described. In the process of producing pulverized coal, coal is stored in the PCI call storage tank 20 through the belt conveyor 15 at a predetermined ratio of unbaked coal and semi-anthracite coal in the coal storage tank 10. PCI is an acronym for Pulverized Coal Injection. The call stored in the PCI call storage tank 20 is transferred to a mill 30 as a pulverized coal manufacturing facility through a coal feeder 25 and is converted into a fine state while being subjected to a grinding process. The call in the fine state is dried and conveyed by the waste gas as hot air, and is conveyed to the bag filter (40). The waste gas used for the transfer is discharged into the atmosphere, and the pulverized coal is stored in the differential storage tank 50. The pulverized coal stored in the pulverized coal storage tank 50 is supplied to the pulverized coal receiving lance 3 through the feed distributor 70 to the air by the nitrogen compressor 4 in the feed tank 60, (2) provided in the blast furnace (1). The amount of pulverized coal injected is set by the operator. The above-mentioned pulverized coal injection work is repeatedly performed until the blast furnace is stopped due to equipment work or the like. Reference numeral 80 denotes a pulverized coal blowing controller for controlling the entire apparatus.

However, in the conventional method of blowing the fine coal into the blast furnace 1 according to the type of the call, the following problems arise.

First, when changing the type of coal and blending (adjusting the ratio of tearless coal and semi-anthracite coal) due to the blowing of a large amount of pulverized coal, the pulverized coal intake amount is taken in the same manner as before the change, So that it is difficult to predict the constant fluctuation of the heat and to control the furnace heat.

Second, as the heat of combustion in the blast furnace rapidly increases, silicon (Si) in the molten iron component rises and the quality of the molten iron is deteriorated. In addition, there is a risk of occurrence of a major accident There was a problem.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned problems, and it is an object of the present invention to provide a method of reducing the amount of heat generated by pulverization of pulverized coal, The present invention provides a method of controlling the furnace in accordance with the characteristics of the pulverized coal which can control the temperature of the furnace steadily and steadily by applying the converted amount per the amount of the per-PCI time.

Another object of the present invention is to provide a method of controlling the furnace for controlling the furnace according to the characteristics of the pulverized coal, which can prevent large accidents such as an increase in the quality of the molten iron and a stoppage of blast furnace operation by constantly and stably controlling the temperature of the furnace inside the furnace have.                         

It is still another object of the present invention to provide a method of controlling the blast furnace according to the characteristics of pulverized coal, which can prevent the air permeability in the furnace and the drift of the furnace gas due to stability of the furnace, .

According to an aspect of the present invention, there is provided a method for controlling a furnace of a furnace according to the characteristics of pulverized coal, comprising the steps of: constructing and storing a data table according to each characteristic of a call; The total inventory amount of the pulverized coal stored in the pre-change coal tank 10, the PCI call storage tank 20, the differential storage tank 50, and the feed tank 60 at the time of adjusting the PCI call type and the mixing ratio is calculated, A second step of calculating a time at which the stock amount can be taken in by the pulverized coal intake variation amount; A third step of setting a pulverized coal blowing start time after the change using the pulverized coal blowing time of the pre-change call calculated in the second step; A fourth step of calculating a deviation heat generation amount before and after the change according to the PCI call type and the composition ratio change; And a fifth step of setting the amount of pulverized coal injected after the change of the kind of coal and the blending ratio by the amount of heat generation of deviation to set the amount of pulverized coal to be blown into the blast furnace 1.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings.

First, a data table according to the type of call will be described with reference to FIG. The types of coal (coal) produced from pulverized coal, which is an alternative fuel to blast furnace, are classified as unbaked AI and semi-anthracite JO, and the characteristics such as moisture (TM), volatile matter (VM) and calorific value And then stored in a process computer (not shown). The tabulated data is stored in the memory device and is read and applied to the calculation when a change in the mixing ratio of the call occurs. The classification described above is an example, and it is possible to classify it into a smaller range or into a larger range.

The necessity of the heat control in the conventional blast furnace 1 is as follows. For example, when the pulverized coal prepared by using one of the blast furnaces (AI) is blown into the blast furnace (1) and the prepared pulverized coal is exhausted to supply new pulverized coal, (AI), the heating value of the tinned coal is in the range of 7386-7548kCal / kg. Therefore, when the same tinned carbon is used, the calorific value variation is not large. However, when using 100% Since the calorific value is in the range of 7458-7910 Kcal / kg, it differs greatly from the calorific value before the change. Therefore, when the product is made into fine powder using the semi-anthracite coal and blown into the blast furnace (1) It becomes necessary.

3 is a schematic block diagram of a PCI manufacturing and blowing facility in which the method of the present invention is performed. As shown in the figure, there are provided a coal tank storage tank weight detector 10A for detecting the call volume of the coal tanks storage tank 10, a call storage tank weight detector 20A for detecting the call volume of the PCI call storage tank 20, A weight detector 50A for detecting the residual amount of pulverized coal in the differential storage tank 50 and a (feed tank) weight detector 60A for detecting the residual amount of pulverized coal in the feed tank 60 are further provided And signals generated from the weight detectors 10A, 20A, 50A, and 60A are input to the process computer 100. [

The data detected from the weight storage detector 10A and the weight storage 20A of the coal storage tank are transmitted from the weighing machines 11 and 21 to detect the weight of the call, On the other hand, it is necessary to pay attention to the pulleys of pulverized coal which are measured by the weight detectors 50A and 60A. Therefore, the weight measured from the weight detectors 10A and 20A is converted into the weight of the pulverized coal corresponding thereto and used in the next step. This weight conversion is performed in the process computer 100, and the formula for converting the weight of the call into the coal stock 10B, 20B and calculating it is shown below.

(Equation 1)

T1 x WO21 = WO2 T1, T1 - WO2 T1 = 10B,

Here T1 is the total basis weight of the pre-change coal deposit tank 10, WO21 is the water content of the call, WO2T1 is the total moisture content, and 10B is the pulverized coal content of the coal storage tank 10. For example, in the weight detector 10A, a process computer (not shown) is connected to the weighing machine 10 by a weight detection signal output from the weighing machine 11 of a pair of ship storage tanks 10, The total weight value 400T x moisture content (8.0 ÷ 100) is calculated for the ship storage tanks 10, assuming that the total weight (T1) = 32T (total water content). Therefore, when the total water content value is decreased (decreased) in the total basis weight value, the pulverized coal volume 10B = 400 - 32 = 368 (T) becomes the total basis weight of the call converted into the pulverized coal volume of the coal tanks 10 to be.

Also, the total basis weight value of the call reservoir 20 is detected by the weighing machine 21, detected by the call storage vessel weight detector 20A, and is also converted to the corresponding amount of pulverized coal in the process computer 100. The equation to be transformed is similar to the above equation and is as follows.

(Equation 2)

T2 x WO22 = WO2T2, T2 - WO2T2 = 20B,

Here, T2 is the weight of the stock in the PCI reservoir before the change, WO22 is the moisture content of the call, WO2T2 is the total moisture content, and 20B is the PCI call storage tank pulverized coal. For example, when the stock weight of a pair of PCI call storage tanks 20 is 660T in total and the water content is 8.0%, the total basis weight value 660T x moisture content 8.0% = 52.8T and 20B = 600 - 52.8 = 607.2T.

As described above, in order to remove the moisture content weight from the total weight of the call, the water contained in the call is removed by using the waste gas of the hot air in the process of crushing the call, and is stored in the differential storage tank 50 and blown into the blast furnace 1 And to calculate the amount of pulverized coal charged into the actual blast furnace 1 by previously removing the amount of water evaporated during the crushing of the coal.

The amount of pulverized coal in the pulverized coal storage tank 50 and the pulverized coal feed tank 60 is in a state in which water has already been removed so that the value detected from the pulverizer tank weight detector 50A and the feed tank weight detector 60A Are directly transferred to the process computer 100 to calculate the pulverized coal quantities 50B and 60B, respectively. Thus, the process computer 100 stores the respective pulverized coal amounts and their total sum. The time required for injecting the unchanged call is calculated by using the sum of the pulverized coal of the coal tank 10, PCI call storage 20, differential storage tank 50, and feed tank 60, .

(Equation 3)

BFT = (10B + 20B + 50B + 60B) / current pulverized coal injection amount (T / Hr),

Here, BFT represents the time required for the call before the change to be taken into the blast furnace, 10B is the pulverized coal output of the coal storage tank, 20B is the pulverized coal output of the PCI call storage tank, 50B is the pulverized coal output of the pulverized storage tank, and 60B is the pulverized coal output it means. For example, if the set amount of pulverized coal blowing in the present blast furnace is 60 T / Hr and the total amount of calls before change, that is, the amount of pulverized coal that can be blown into the blast furnace is 1210.2 T, 1210.2 T ÷ 60 T / Hr = 20 hours and 17 minutes. This time is 20 hours and 17 minutes before the change can be injected into the blast furnace as pulverized coal. Referring to FIG. 4, the blast furnace blowing time calculated by the processor computer 100 according to the amount of pulverized coal before the call type change and the remaining inventory amount is calculated by the host controller 200 (Not shown). Fig. 4 is a block diagram of a control unit in which the method of the present invention is performed. In Fig. 4, a process computer 100 performs an operation of collecting the above-described pulverized coal volume to calculate an inventory load time.

The blast furnace intake remaining time calculated as described above is calculated by subtracting 3 hours (3Hr), which is a delay value of the fluctuation time in the blast furnace due to call fuel change, to calculate the blast furnace start time after changing the call fuel do. This is derived from the fact that the change in the amount of pulverized coal injected during the operation of the blast furnace is calculated by the experience and the actual data, and the fluctuation of the pulverized coal injection amount is inferred from the fact that the inside heat of the blast furnace fluctuates after 3 hours. This delay time can be expressed by the following equation (4).

(Equation 4)                     

BFT1 = BFT - 3 (Hr)

Here, BFT is the time required for blowing in the blast furnace before the change, and BFT1 is the time required for starting blowing in the blast furnace after the change. The above Equation 4 is built in the host controller 200. When the required pulverized coal intake time calculated by Equation 3 is inputted, the pulverized coal processing computer 300 ). The reason why the start time of the start of blowing is restrained as shown in Equation 4 is that if the fluctuation state of the furnace is known after 3 hours at the time of fluctuation of the pulverized coal blown amount, the call before the change is undifferentiated, The change in the pulverized coal blowing rate after the change can be maintained at the same level as the fluctuation of the pulverized coal blowing at the completion of the pulverization before the change. However, the calorific value has not yet been corrected in this state.

After the pulverized coal injection start time is calculated after changing the coal type or the blending ratio as described above, the pulverized coal amount compensation step is carried out by calculating the calorific value deviation before and after the change of the coal type, unpeeled coal, and semi-anthracite ratio adjustment (i.e., blending). The following equations are for calculating the compensation heat quantity. This is a necessary process for constantly controlling the internal temperature of the blast furnace to the set temperature.

(Equation 5)

K1 = PCR × heating weight (X1) × blowing rate (R1)

(Equation 6)

K2 = PCR × heating weight (X2) × blowing ratio (R2)                     

(Equation 7)

K = K1 - K2,

K1 is the heat quantity before the call change, K2 is the heat quantity after the call change, PCR is the pulverized coal intake (KG / T), and the weighted heat quantity (X1) The heat amount and the weighted heat amount X2 of the type show the heat amount of the call type after the change, the take-in ratio R1 represents the call use ratio before the change, and the take-in ratio R2 represents the call use ratio after the change.

By converting the amount of pulverized coal used per day from the production of charcoal produced per day, the amount of pulverized coal injected to produce one ton of charcoal can be obtained, which is indicated by PCR. The calorific value of the coal (coal) classified according to the respective characteristics is the weighted calorific value, and the call mixing ratio before change is expressed as the blowing rate, and the call types before and after the change are processed by the coal processing computer 90 When it is transmitted to the computer 100, the amount of the carbon monoxide coal before change is calculated by the equation (5). Further, when the changed value of the amount of the carbon monoxide after the change is calculated by the formula 6 and the amount of the changed value of the amount of the carbon monoxide after the change is subtracted from the pre-change amount of the amount of carbon monoxide, the calorific value before and after the change of the call is calculated. The calorific value compensation value is calculated in the process computer 100 and calculated as the pulverized coal blown amount and transferred to the blast furnace processing computer 300. The calorific value compensation value is transmitted to the pulverized coal blowing controller 80. In the pulverized coal blowing controller 80, the deviation calorific value / pulverized coal load is calculated by dividing the calorific value K calculated in the above formula 7 by the calorific value of pulverized coal 1T, The amount of pulverized coal is calculated. This is shown in Equation (8).

(Expression 8)                     

Kx = K / P1,

Here, Kx represents the amount of pulverized coal to be blown after the change, K represents the heat amount of deviation calculated in the above formula (7), and P1 represents the amount of heat of 1 T tone of the pulverized coal. In the process computer 100, the value obtained by subtracting the K _X value from the current pulverized coal injection amount is transmitted to the blast furnace processing computer 300. The transferred value is the amount of pulverized coal blown calculated by calculating the amount of heat generated by the deviation. In the blast furnace computer 300, this value is transferred to the pulverized coal blowing controller 80, and the pulverized coal blowing controller 80 blows pulverized coal at the start blowing time after changing the type of coal.

The method of the present invention as described above will be described using specific examples.

It is assumed that the data for each type of un-munition (A-I) and semi-anthracite (J-O) classified according to the characteristics of the call are stored in the process computer 100 in tabular form as shown in FIG. In order to change to 100% semi-anthracite (J) with a calorific value of 7910 Kcal / Kg from 100% unbaked coal (A) with a calorific value of 7368 Kcal / Kg due to lack of pulverized coal in stock during blast furnace operation at blast furnace (1) And inputs the mixed signal of the call type and the mixing ratio.

When the call change signal is input, the process computer 100 causes the weight detector 10A of the coal bed storage tank 10, the weight detector 20A of the call storage tank 20, the weight detector 50A of the differential storage tank 50, ) And the weight detector 60A of the feed tank 60 are used to calculate 1) the amount of limited pulverized coal in the water content of the pre-pulverized coal alteration tank 10, 3) calculating the amount of pulverized coal stored in the differential storage tank 50 and the feed tank 60, and 4) calculating the total amount of the remaining pulverized coal before the call change. After calculating the total amount of pulverized coal, the process computer 100 calculates a remaining take-in time at which the pulverized coal can be taken into the blast furnace 1.

For example, if the stock quantity of the pre-change ship deposit tank 10 is 400T, the inventory quantity of the PCI call storage tank 20 is 660T, the stock quantity 50B of the differential storage tank 50 is 150T, 60B is 235T and the moisture content of the call is 8%, the amount of pulverized coal in the pre-stored coal tanks 10 is 368T (10B) according to the above-mentioned Equations 1 and 2, The amount is 607.2T (20B). At this time, the pulverized coal of the pulverizer tank 50 and the feed tank 60 is in a state in which moisture has already been removed, so that the pulverized coal is directly used without removing the moisture content. When the pulverized coal inventory amounts before the call change are calculated as described above, the respective pulverized coal inventory amounts are added to calculate the total amount. The calculation of the total amount is calculated by the above-described Equation 3. In the above example, the total amount of pulverized coal is 1360.2 T, which is divided by the current pulverized coal injection amount, 1360.2 ÷ 60 = 22 hours and 40 minutes, and pulverized coal can be taken during this time. When the remaining time of the pulverized coal intake is calculated as described above, the process computer 100 transfers the calculated value to the upper computer. The host controller 200 uses this value to calculate the changed pulverized coal blowing start time using the above-described expression (4). That is, after 22 hours, 40 minutes and 3 hours = 19 hours and 40 minutes, the pulverized coal injection start time is reached.

5 and 6 show an example of the change in the pulverized coal blowing start time as described above. This is not based on the calculation formula for the above-described pulverized coal volume but on the amount of the blown powder. 5 is based on the pulverized coal intake remaining time calculated by Equation 3 in the process computer 100, and FIG. 6 is the blowing start time calculated by Equation (4).

For example, when the blowing amount is 20T, the blowing start time is 50 hours later. However, in FIG. 6, the blowing start time is about 47 when the blowing amount is 20T. In addition, in the case where the blowing amount is 40T, the blowing start time is 26 hours, but it is about 23 hours in FIG.

(A) to (7) when converted into a fuel cost based on a deviation in calorific value generated when the pulverized coal type is changed from a tear-off coal (A) to a semi-anthracite coal (J) The calculation of the input calorie difference at the time of changing the call type with the semi-anthracite (J) is as follows.

K = K1 - K2

(PCI 60T / Hr) 占 1000kg / T 占 Heat (BI (A): 7386Kcal / kg) 占 24Hr / D / Production amount (9000T / D) (Kcal / TP) = -82,400 (Kcal / TP) is calculated as follows: T × heat amount (CB (J): 7901 Kcal / kg) × 24Hr / D ÷ production amount (9000T / D)] = 1181760 .

When the difference in the amount of applied heat is converted into the pulverized coal blow-in ratio (PCR / T-P)

Kcal / T-P (calories per unit) ÷ calories per kg of PCI (Kcal / Kg) → (Kg / T-P) =

PCR - 82,400 Kcal / TP / 7600 (Kcal / Kg) = -10.84 (Kg / TP) .

PCR (Kg / T-P) x production (9000 T / D) ÷ 24 (Hr / D) ÷ 1000 (Kg / T)

10.84 (Kg / TP) 占 9000 (T / D) 占 24 (Hr / D) = -4.07 (T / Hr) .

The value of -4.07 (T / Hr) is sent from the process computer 100 to the host controller 200. This is the amount of pulverized coal injected by the amount of deviation before and after the change, And sends the pulverized coal blown amount minus the compensation heat amount to the blast furnace processing computer 300. In the blast furnace processing computer 300, the deviation heat quantity is converted into the pulverized coal intake amount from the current pulverized coal intake amount at 3 hours before the total stock amount before the change is fully blown into the pulverized coal blowing controller 80, that is, 19 hours and 40 minutes calculated from the pulverized coal blowing start time Automatically adjusts the intake amount per PCI time calculated as 60 - 4. 07 = 55.9 T / Hr. Therefore, as shown in FIG. 8, the amount of pulverized coal is reduced compared with the previous one, but the heat of the coal can be adjusted due to an increase in the calorific value after the change.

In another embodiment, the case where the ratio of the call type is changed from 40:60 to 60:40 for the un-muddy and the semi-anthracite is described as follows. First, the pulverized coal intake inventory of the shipbuilding storage tank 10 and the pulverized coal intake inventory of the PCI call storage tank 20 are obtained, and the total pulverized coal volume of the pulverized coal storage tank 50 and the feed tank 60 is calculated to calculate the total stock amount of pulverized coal . And calculates the pre-change pulverized coal residual blowing time using the calculated total stock quantity. It is assumed that the remaining take-in time and total inventory amount are the same as in the above embodiment.

In addition, the difference in the amount of heat input when using the composition change is calculated as follows.

(0.6 × PCI 60 T / Hr) × 1000 kg / T × heat amount (BI (A): 7386 Kcal / kg) × 24 Hr / D / production amount (9000 T / D) (A)) / T × heat amount (BI (A): 7901 Kcal / kg) × 24Hr / D ÷ production amount (9000T / D)] - {[(0.6 × PCI 60T / Hr) (A): 7901 Kcal / kg) 24 Hr / D / Production amount (9000 T / Hr) x 1000 kg / / D)]} = 1,231,200 - 1,214,720 = 19,227Kcal / TP.

The difference in the input calorific value is converted into the pulverized coal injection ratio (PCR / T-P) as follows.

(Kcal / TP) ÷ (0.6 × 7386 + 0.4 × 7901) = 2.53 (Kg / TP) as the heating weight of the modified call (Kcal / Kg) When this is converted into PCI (T / Hr), 2.53 (Kg / TP) x 9000 (Kg / TP) is calculated by PCR (Kg / TP) x production amount (9000T / D) / 24 (Hr / D) / 1000 T / D) / 24 (Hr / D) / 1000 (Kg / T) = 0.95 T / Hr.

In summary, in the case of changing the mixing ratio of the call type to 40%, 60% to 60% and 40%, respectively, the tearless carbon (A) and the semi-anthracite (J) After 19 hours and 40 minutes to the controller 80, the pulverized coal setting amount is transferred to the blast furnace processing computer 300 from the host controller 200 to take 60.95 T plus 0.95 T / Hr. Therefore, as shown in FIG. 9, the amount of pulverized coal is increased but the amount of heat generated decreases, so that the heat of the blast furnace 1 is controlled to be controlled according to the characteristics of the pulverized coal.

According to the present invention as described above, in the case of changing the type and the mixing ratio of the tearless coal or the semi-anthracite coal during pulverized coal blowing operation into the blast furnace, the amount of heat generated per the pre- By applying stable and constant temperature control, it is possible to prevent large accidents such as increase in quality of charcoal and shutdown of blast furnace. In addition, it can prevent ventilation in the furnace and drift in the furnace gas due to stability of the furnace, and also can increase the productivity and reduce the fuel cost due to the furnace bottom temperature and the stability of the furnace lime.

Claims (4)

A control method for controlling a temperature inside a blast furnace in accordance with characteristics of pulverized coal supplied to a blast furnace (1) A first step of constructing and storing a data table according to each characteristic of the call; The total inventory amount of the pulverized coal stored in the pre-change coal tank 10, the PCI call storage tank 20, the differential storage tank 50, and the feed tank 60 at the time of adjusting the PCI call type and the mixing ratio is calculated, A second step of calculating, by the process computer (100), a time at which the stock amount can be taken in by the pulverized coal intake variation amount; A third step of setting, by the host controller 200, the pulverized coal injection start time after the change, using the pulverized coal injection time of the unchanged call calculated in the second step; A fourth step of calculating a deviation heat generation amount before and after the change according to the PCI call type and the composition ratio change; And a fifth step of re-setting the amount of pulverized coal injected after the change of the kind of coal and the blending ratio due to the amount of heat generated by deviation, and blowing it into the blast furnace (1). The method according to claim 1, Wherein the data table according to the call type in the first step is classified according to the size of the coal, the moisture content, the volatile content, and the calorific value of the coal. The method according to claim 1, Wherein the weight value obtained by removing the water content from the weight value of the call stored in the coal deposit storage tank (10) and the PCI call storage tank (20) in the calculation of the pulverized coal inventory amount in the second step is calculated as the pulverized coal inventory amount value The method comprising: The method according to claim 1, Wherein the pulverized coal blowing start time in the third step is set by subtracting 3 hours from the pulverized coal blowing start time calculated in the second step.

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