KR20060065761A - Prompt estimation method for coke quality and coke oven tester - Google Patents

Abstract

The present invention improves the disadvantage that it takes a long time to measure the quality of the coke produced after charging the coke oven in the coke oven after a certain period of time, and at the same time, the physical properties of the coke in a constant operating conditions of the coke oven That is, even if the compounding index is uniformly blended, coke manufacturing coke is used to solve the problem that the quality of coke produced in the coke oven is difficult to analyze and cope with it. From the method for estimating the quality of the coke to be produced in the coke oven in a short time.

Coke, Coke Quality Measurement, Type I Drum Strength, Coke Cake, Coal

Description

Coke quality measuring method and its measuring device {PROMPT ESTIMATION METHOD FOR COKE QUALITY AND COKE OVEN TESTER}

1 is a schematic view showing a one-way coal distillation furnace for preparing a coke cake according to an embodiment of the present invention.

Figure 2 is a schematic diagram showing a refractory mold for coke cake production according to an embodiment of the present invention.

3 is a graph showing the correlation between the type I drum strength and the coke drum strength.

The present invention relates to coke used in the steelmaking process, and more particularly, to a method and apparatus for measuring the quality of coke produced in a coke oven quickly and accurately.

Coke used in the iron making process serves as a reducing agent to reduce iron ore in the blast furnace, serves as a heat source of the blast furnace that generates a large amount of heat by reacting with oxygen, and maintains the air permeability in the blast furnace to facilitate the internal reaction in the blast furnace It is an important raw material for steelmaking.                         

Such coke is produced in a coke oven in which a carbonization chamber for coal drying and a combustion chamber for supplying a heat source for the drying are alternately heated.

In the manufacturing process of coke, various types of coal are blended under a certain mixing condition, and then the blended coal is charged into a carbonization chamber so that the particle size of the blended coal is 80 to 90% of 3 mm or less. And carbonized for 18 to 20 hours from the carbonization chamber wall heated to 1000 to 1100 ° C. from the combustion chamber.

Coal used in the manufacture of coke has the property of softening-melting and caking when heated is a basic requirement. Coal charged in the carbonization chamber undergoes a soft melting process at 350-500 ° C. as a heat transfer from an oven wall, and undergoes a solidification shrinkage process at 500-1100 ° C. to form a coke cake.

The coke quality produced in the coke oven depends largely on three factors. In other words, the quality of coke is determined by blending raw coal, pretreatment of charged coal, and oven drying conditions.

Here, the mixing of raw coal is an internal factor and the other two are external factors. Factors related to the blending of raw coal include the coal composition, the degree of coalification, the mixing ratio, and the coking property.The factors for the pretreatment of the charged coal are the raw coal granulation and the charged coal moisture. Total dry time.

The coke quality control produced in the coke oven is based on the stable quality of the raw coal to be blended and the consistent operating standards of charging coal pretreatment and oven drying conditions.The quality of the raw coal is greatly affected by the quality of the coke. This is very important.

Volatile fraction, flow rate, total expansion, inert content, tissue equilibrium index (CBI), average reflectance of the coal as a blend management index to maintain the coal coal, that is, the coal, of coal quality used in the manufacture of coke It mix | blends so that a back may exist in a fixed range.

However, since the coke quality fluctuates even though the compounding index is within a certain range, there is a need for a method to more accurately determine the quality of the charged coal in terms of coke quality.

When predicting coke quality from charged coal quality, an immediate analysis can be made with an accurate analysis of raw coal blending and operations when coke quality changes.

However, the coal blended in the conventional coke oven is charged into the coke oven, and it takes a long time of about 30 hours or more to measure the quality of the coke produced by coking.

As such, it takes a long time, it is difficult to analyze the cause when the coke quality fluctuations in the actual operation process, and there is a lot of difficulties in coke quality control because the ability to cope with raw coal blending and oven operation change is poor.

Therefore, a method for quickly evaluating the coke quality to be produced in the oven from the coke making coal is indispensable.

Conventionally, the effects of raw coal and blended coal properties and oven operating conditions on the coke quality have been investigated using a coke oven, and various methods for predicting the coke quality produced in the coke oven have been proposed.

One of these measures is CANMET, Canada, which presented a correlation for estimating coke quality using charge density, tooth time, degree of coalification and coke inerts of charged coal. (57th Ironmaking Conf. Proc., 1998).

In addition, there is a plan of Kansai coke and chemical company in Japan, which analyzes the effect of the final drying temperature and heating rate of coking on the coke strength (Fuel, 1997).

Another example is Japanese Laid-Open Patent Publication No. 2002-020760, which relates to a method of estimating coke strength from an estimation formula obtained by using a blending ratio, maximum flow rate, and coaling degree of each raw coal during coke production.

Another example is Japanese Laid-Open Patent Publication No. 2000-063846, which relates to a method of estimating the cold strength and hot strength of the manufactured coke by measuring the properties of coal charged into the coke oven.

However, these methods predict the quality of coke produced from raw coal properties and coke oven operating conditions. When several types of raw coals are mixed and used as coking coal for coke production, the raw coal properties are mixed due to the difference in blendability of the raw coals. By predicting the quality of coke, there is a lot of difficulty in predicting the quality of coke when the blending of raw coal is changed.

 The present invention improves the disadvantage that it takes a long time to measure the quality of the coke produced after charging the coke oven in the coke oven after a certain period of time, and at the same time, the physical properties of the coke in a constant operating conditions of the coke oven In other words, even if the compounding index is uniformly formulated, it is invented to solve the problem that the quality of coke produced in the coke oven has difficulty in stabilizing the coke produced in the coke oven due to its ability to analyze the cause and cope with it. Its purpose is to provide a method for quickly estimating the quality of coke to be produced in a coke oven from coke making coal.

In order to achieve the above object, the present invention comprises the steps of preparing a coke cake in a rapid heating furnace by filling the coal for the coke production; and loading the prepared coke cake into the type I drum strength machine drum type I drum strength of the coke cake Measuring; And it provides a coke quality measurement method for predicting the coke quality using the measured I-type drum strength.

Here, the coke quality measurement method according to the present invention is calculated by the following equation using the measured I-type drum strength.

DI ¹⁵⁰ ₁₅ = 0.987 * (Type I drum strength) + 21.222

(Herein, DI ¹⁵⁰ ₁₅ represents the drum strength measured by the weight ratio of coke particles of 15 mm or more after 150 kg of coke with a size of 25 to 100 mm is rotated 150 in a 1.5 m diameter drum.)

In addition, the present invention has a particle diameter of less than 2mm in the refractory mold having a plurality of holes of 20-30mm in diameter, 13-28mm in height so that the coal heated in the one-way coal distillation furnace can be dried in one direction. A coal sample is charged to 700 kg / m ³ (based on dry coal) and dried for 1 to 1.5 hours at a drying temperature of 850 to 900 ° C. to prepare a coke cake.

In addition, the present invention is to measure the I-type drum strength of the coke coke cake type I by rotating alumina or glass beads in the I-type drum strength machine to rotate the prepared coke cake type I by the weight ratio of the coke cake after the rotation Measure the drum strength.

And the beads introduced into the type I drum strength machine is glass beads and is 1 to 6 times the weight of the prepared coke cake, the type I drum strength machine is rotated for 10 to 20 minutes, the coke cake weight ratio after the rotation is the Use a coke cake 10 mm or more.

In addition, the present invention is formed in a coal distillation furnace that is insulated with a heat insulator and a heater is installed at the bottom bottom to heat the raw coal in one direction and the atmosphere is controlled by nitrogen gas; A refractory mold, which is charged into the chamber and is made of a heat insulating material having a plurality of holes formed therein for filling coke raw material coal; A refractory weight for pressing the refractory mold while covering all of the holes formed in the refractory mold; A hatch installed at an upper portion of the chamber and configured to charge the refractory mold filled with the raw coal into or out of the chamber; It also provides an apparatus for producing a coke cake for coke quality measurement comprising a.

In the refractory mold used in the coke cake manufacturing apparatus, the holes for filling the raw coal formed therein are 20 to 30 mm in diameter and 13 to 28 mm in height.

DETAILED DESCRIPTION Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention. In the accompanying drawings, only parts necessary to clearly describe the present invention are shown, and like reference numerals designate like elements throughout the specification.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a view showing an example of the present invention and shows a schematic diagram of a one-way coal distillation furnace for producing a coke cake sample.

As shown in FIG. 1, the apparatus for measuring coke quality according to the present invention is filled with coal 2 used in the manufacture of coke for steelmaking in a certain type of refractory mold 4 installed in a one-way coal distillation unit. By coking to prepare the coke cake, and measuring the strength of the coke cake prepared in the Type I strength tester, it is possible to quickly estimate the quality of the coke to be produced from the charging coal charged in a commercial coke oven.                     

Referring to the one-way coal distillation furnace 10 for producing the coke cake shown in Figure 1, the one-way coal distillation furnace 10 is composed of a double chamber (0.12mW × 0.12mL × 0.15mH) (6), the chamber The heater 1 was installed in the bottom of oven in order to heat the coal charged in (6). Coal charged in the chamber 6 was insulated from the bottom of the oven and the wall with heat insulator so that dry matter could proceed by heat transfer from the bottom to the top, that is, in one direction, and the atmosphere was controlled by nitrogen gas in the chamber.

Then, in order to take out the coke cake prepared after charging the coal into the chamber 6 and taking out the experiment, the upper part of the one-way coal distillation furnace 10 was manufactured in the form of a hatch 5, and a motor connected to the hatch 5 To move up and down using The dry gas generated during the coal distillation process was discharged to the flue through a discharge pipe (To stack).

And a mold (11 cm x 11 cm x 1.3-2.8 cm in height) (4) was produced using a heat insulation board and a lead to produce a coke cake of a certain form from raw coal.

The refractory mold 4 is made of a heat insulating material so that the filled coal 2 is heat-transferred in the height direction, and a plurality of predetermined sized holes (for example, 20 to 30 mm in diameter, for filling coal in the refractory mold 4) A height of 13 to 28 mm) 10 was drilled.

In the process of filling the raw coal sample 2, the moisture in the raw coal is first measured, and then the particle size is 2 mm or less, and the hole in the mold 4 is filled so that the packing density is 700 kg / m ³ on a dry coal basis. The mold 4 filled with the coal sample 2 was dried in a one-way drying furnace heated to a constant temperature for a predetermined time, and then taken out, and then suffocated in a vacuum oven.

A refractory weight 3 is placed on top of the mold in order to prevent the coal 2 filled in the mold 4 from expanding in the height direction during the drying process.

Hereinafter, a process of preparing a coke cake will be described.

First, the heater 1 is heated to have a constant temperature by using the heater 1 under the chamber 6 installed in the one-way coal distillation furnace 10. Then, the raw material coal is prepared as described above, and when the heater temperature reaches the desired temperature, the hatch 5 of the upper part of the one-way coal distillation furnace 10 is lifted up, and then the mold 4 filled with the desired coal sample is filled. ) Into the chamber (6) and put the weight (3) on the surface of the mold (4). And the one-way coal distillation lowers the hatch 5 of upper part, and dry distillation starts.

After a certain time (1 to 1.5 hours) has passed since the start of coal distillation, the experiment is terminated, the hatch 5 is lifted up, the mold 4 and the coke cake prepared are taken out and sintered in a vacuum oven.

The prepared coke cake was measured for quality in a type I drum strength machine. The type I drum strength of the coke cake produced is correlated with the quality of the coke produced in the coke oven, so that the quality of the coke produced in the coke oven can be estimated by measuring the quality of the coke cake.

The quality evaluation of the coke cake in the type I drum strength machine was as follows. A coke cake sample prepared in a Type I drum stiffener (13 mm ID x 700 mm length) was placed and then rotated 600 times for 30 minutes. The coke cake sample was classified into a 10 mm sieve to obtain a weight ratio of the coke cake of 10 mm or more to evaluate the quality of the coke cake. It was.

<Example 1>

In order to produce a coke cake of a certain shape from coal, the various types of holes (diameter 20-30mm x height 13-28mm) 10 which can fill the refractory mold 4 with the coal 2 of the coal 10 Coke cakes were prepared by varying the packing density, the drying temperature in the one-way coal distillation furnace, and the drying time to derive the appropriate manufacturing conditions.

For tan A tan strengths for the production of water of 10% coke and the refractory mold 4 (diameter 25mm, height 23mm), filling density 700kg / m ³ (dry carbon basis), a packing density in the refractory mold (diameter 30mm, height 28mm) in Coal samples were charged to 750 kg / m ³ (wet coal base) and the top of the coke cake remained undried when dried for two hours in a one-way coal drying furnace heated to 800 ° C. Such dry distillation conditions need to increase the dry distillation temperature and time further.

When the dry distillation conditions were dried for 2 hours at 900 ° C. under the above charging conditions, the upper part of the coke cake was coked after passing through the coal stocking temperature (600 ° C.) to prepare a coke cake of a certain type.

Then, for the coke coal for making coke with 10% moisture, the packing density in the refractory mold (diameter 25 mm, the height 23 mm) was 750 kg / m ³ (based on the coal) and the refractory mold (diameter 30 mm, the height 28 mm). Coal samples were charged to 800 kg / m ³ (wet coal basis), and coke cakes of some form were prepared when dried in a one-way coal drying furnace heated to 900 ° C. for 3 hours.

In addition, in order to manufacture a coke cake in a short time, the filling density of a refractory mold (20-30 mm in diameter and 13 mm in height) is applied to the coking coal of 10% of moisture and coking coal of 9% of moisture used for coke production. When coal is charged to 700kg / m ³ (dry coal standard) and dried for 1 to 1.5 hours at 900 ~ 950 ℃ in a one-way coal-drying furnace, uncoated upper portion of coke cake and cracks in coke cake do not occur. Coke cakes were made.

Therefore, the coke cake which maintains a constant form from the coal-making coal from rapid heating from the rapid heating from the present invention, the coal (2) filled in the refractory mold (diameter 20-30mm, height 13mm) (4) in the one-way coal distillation furnace It could be prepared by.

Coal and dry distillation conditions for coke cake production are as follows. Coal sample less than 2mm, the mold form is made of refractory to fill the coal to have a number of holes 20-30mm in diameter, 13-28mm in height 10, coal filling density is 700kg / m ³ (based on dry coal), The drying temperature was 850-900 ° C and the drying time was 1-1.5 hours.

<Example 2>                     

To evaluate the quality of the coke cake prepared by using a type I drum (diameter 13 mm x length 700 mm) used for measuring the strength after the CO ₂ reaction of the coke produced in a commercial coke oven.

Coal samples used in the coke cake production were used for coking coal A, coking coal B, charcoal C, and charcoal D, which are used for producing coke for steelmaking.

Coal was packed into a refractory mold at a packing density of 700 kg / m ³ (based on dry coal) and dried for 1.5 hours in a one-way distillation furnace heated to 900 ° C. to prepare a coke cake.

The prepared coke cake was to have a size of 30mm in diameter, 13mm in height. In the type I drum strength tester, the coke cake quality was evaluated by rotating the coke cake at 600 revolutions for 30 minutes, and measuring the weight fraction of 10 mm or more after rotation differentiation, and the results are shown in the table below.

Coal sample I drum strength (wt%) Example A 77.7 Example B 74.2 Example C 76.1 Example D 76.0

As shown in Table 1, the discriminating force by the I drum strength of the coal briquettes A and B is shown to be slightly smaller, about 3.5%, and the two examples of the loaded coals are almost similar.

In order to increase the discrimination of I drum strength of coke cakes prepared from Examples A and B bullets, the coke cake was put together with glass and alumina to increase the wear of the coke cake. Now.

Coke cakes were prepared by filling the refractory molds with coal densities of 700 kg / m ³ (dry coal basis) for 1.5 hours in a one-way distillation furnace heated to 900 ° C. for coal A and B coals.

The prepared coke cake was to have a size of 30mm in diameter, 13mm in height. I Drum measurement is to be performed at 600 rotation (20rpm) for 30 minutes, but when measuring the addition of beads, after 200 rotations for the first 10 minutes, re-inject the weight after 200 rotations for 10 minutes, and 200 rotations for 10 minutes. It was made.

For a total of 30 minutes, 600 turns were the same, but every 200 turns (10 minutes), the coke cake was taken out and weighed more than 10 mm.

The result of measuring the same amount of glass beads (6 mm in diameter) with the coke cake by putting it in the I drum strength device is shown in Table 2 below. As shown in Table 2, the I drum strength of hard coal A and B bullets is about 10, which is greater than that before glass beads.

Sample Name I drum strength (wt%) 200 turns 400 turns 600 turns Example A 89.1 83.2 77.4 Example B 79.7 72.1 66.0

In addition, the coarse cake with double weight of alumina beads (diameter 10mm) was put into the I drum stiffener and the results are shown in Table 3 below.

Sample Name I drum strength (wt%) 200 turns 400 turns 600 turns Example A 89.0 80.1 71.2 Example B 82.3 72.0 63.4

As shown in Table 3, the drum strengths of the example A-coal and A-B coals are about 8 by the addition of alumina beads. This resulted in higher discrimination power than when no beads were added, but lower density than glass beads with lower density than alumina beads.

I As a result of the beading to improve the discriminating power in the drum strength evaluation, the discriminating power of the hard coal and the coal is greatly increased, and the low density of the beading causes less coke cake wear as a whole, but more low-quality coal is used. Wearing greatly increased the discriminating power between hard coal and ordinary coal.

In order to further increase the discrimination ability between the coke cakes, the I drum strength measurement was performed by changing the coke cake manufacturing conditions and the amount of glass beads introduced.

Coal samples strength (based on dry peat) Tan Tan A, was used for general shots B shot A and shot B and a mixture of carbon with 50: 50, respectively (A + B) carbon, coal in the mold 700kg / m ³ the It was filled so as to dry, and dried in a one-way distillation furnace heated to 850 ℃ 1 hour to prepare a coke cake.

The coke cake produced was 30 mm in diameter and 13 mm in height. Since the glass bead was more distinguished when I drum strength was measured, the amount of glass beads (6 mm in diameter) used in I drum strength was increased by 6 times the coke cake.

Table 4 below shows the results of the I drum strength measurement when the glass bead dose was increased six times the amount of coke cake for the coke cakes of Examples A, B, and (A + B) blended coal. .

Sample Name I drum strength (wt%) 200 turns 400 turns 600 turns Example A 73.7 60.5 47.8 Example B 58.4 44.3 33.9 Example (A + B) Combination Carbon 67.0 55.9 46.2

As shown in Table 4, the discriminating force of the I drum strength between the example coking coal (A coal) and the example coal (B) was about 14 to 16, and when the number of rotations of the drum strength is high, the discriminating force between the two coal types is high. It appeared to decrease somewhat.

Therefore, when manufacturing the coke cake, the dry water temperature and the drying time are controlled under the condition that the upper part of the coke cake can reach the solidification temperature, and when the appropriate amount of glass beads is injected, the discriminating power of the hard coal and the ordinary coal against the I drum strength is greatly increased. Could increase.

In addition, coke was prepared by the can test in a commercial coke oven for Example A, Example B, and Example (A + B) compounded coal to evaluate coke quality.

Here, the coke quality is evaluated according to the JIS rule as the drum strength, the 10kg coke of size 25 ~ 100mm 150 rotation in a 1.5m diameter drum and then measured by the weight ratio of coke particles 15mm or more, expressed as DI ¹⁵⁰ ₁₅ .

The coke quality for Example A, Example B, and Example (A + B) blended coal was 81.6, 65.2, and 75.4, respectively. From the results in the table above, the coke cake's discriminant power for coal A and coal B is 16, which is similar to the difference in coke quality produced by can test in commercial coke ovens, respectively. It is believed that the quality of coke produced from coal charged to the coke oven at a level can be used in a short time.

FIG. 3 shows the correlation between the quality of the coke cakes produced in a short time and the quality of the coke produced by can test in a commercial coke oven.

In FIG. 3, the DI ¹⁵⁰ ₁₅ strength and the I drum strength indicating the coke quality are highly correlated, and can be represented by the following correlation.

DI ¹⁵⁰ ₁₅ = 0.987 * (I drum strength) + 21.222

Correlation Coefficient (R ² ) = 0.99

Although the preferred embodiments of the present invention have been described above, the present invention is not limited thereto, and various modifications and changes can be made within the scope of the claims and the detailed description of the invention and the accompanying drawings. Naturally, it belongs to the scope of the invention.

 As described above, a method of quickly estimating the quality of coke to be produced in a coke oven from the coke for producing coke according to the present invention is to make the physical properties of the charged coal charged into the oven under a constant operating condition of a commercial oven. In the case of fluctuations in the quality of the coke produced, it is possible to provide a cause analysis and a rapid response capability to stabilize the coke quality produced in the coke oven.

In addition, by estimating the quality of the coke to be produced in the coke oven from the coke for the production of coke in a short time as described above, there is an advantage of providing the effect of contributing to the optimal formulation derivation and stabilization of the coke oven operation when mixing the raw coal.

Claims (7)

Preparing a coke cake in a rapid heating furnace by filling coal for producing coke; Charging the manufactured coke cake with an I-type drum strength device to measure I-type drum strength of the coke cake; Coke quality measurement method for predicting the coke quality using the measured I-type drum strength. In claim 1, The coke quality measurement method is a coke quality measurement method, characterized in that calculated using the following I-type drum strength. DI ¹⁵⁰ ₁₅ = 0.987 * (Type I drum strength) + 21.222 (Herein, DI ¹⁵⁰ ₁₅ represents the drum strength measured by the weight ratio of coke particles of 15 mm or more after 150 kg of coke having a size of 25 to 100 mm is rotated in a drum of 1.5 m diameter.) In claim 1, The coke cake manufacturing step A coal sample having a particle diameter of 2 mm or less in a refractory mold having a diameter of 20 to 30 mm and a height of 13 to 28 mm in order to allow the coal heated in the one-way coal distillation furnace to dry in one direction is 700 kg / m ³ (dry coal). And coking for 1 to 1.5 hours at a dry distillation temperature of 850 to 900 ° C. to produce the coke cake. In claim 3, Measuring the type I drum strength of the coke coke cake Coke quality measurement method characterized in that the coke cake is rotated by putting together alumina or glass beads in a rotating drum type I drum strength machine, and then the type I drum strength by the coke cake weight ratio after the rotation. In claim 4, The beads introduced into the type I drum strength machine are glass beads and are 1 to 6 times the weight of the prepared coke cake, and the type I drum strength machine is rotated for 10 to 20 minutes, and the weight ratio of the coke cake after the rotation is increased after the rotation. The coke quality measurement method characterized in that the type I drum strength is measured by using a coke cake 10mm or more. A chamber formed in a coal distillation furnace that is insulated with heat insulator and provided with a heater at the bottom thereof to heat raw coal in one direction, and to control the atmosphere with nitrogen gas; A refractory mold, which is charged into the chamber and is made of a heat insulating material having a plurality of holes formed therein for filling coke raw material coal; A refractory weight for pressing the refractory mold while covering all of the holes formed in the refractory mold; A hatch installed at an upper portion of the chamber and configured to charge the refractory mold filled with the raw coal into or out of the chamber; Apparatus for producing a coke cake for coke quality measurement comprising a. In claim 6, The raw coal filling hole formed in the refractory mold has a diameter of 20 to 30mm, a height of 13 to 28mm formed apparatus for producing a coke cake for coke quality measurement.

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