KR100554729B1 - Method for measuring moisture constant in blending raw material and method for blending raw material by using it - Google Patents

Abstract

The present invention relates to a method for producing a sintered ore by correcting the main water content in the mixer while measuring the moisture content of the blended raw material discharged from the mixer of the sintering equipment, the purpose of which is active in changing the layer height of the blended raw material discharged from the mixer The present invention provides a method for accurately and reproducibly measuring the moisture content of a blended raw material and a method of mixing in a mixer that can improve the productivity and strength of the sintered ore using this moisture measuring method.

The present invention for achieving the above object, in the method for measuring the water content of the blended raw material discharged from the mixer of the sintering equipment and conveyed on the conveyor belt,

Continuously exposing a predetermined amount of the compounding material in the compounding material layer transferred on the conveyor belt to the surface;

The pressing roller connected to one side of the hinge shaft is made to contact the surface of the blending material to flatten the blending material so that the eccentric load acts on the hinge shaft installed on the conveyor belt, and is integrated at the rear of the pressing roller (along the material feeding direction). Measuring the moisture content of the blended raw material flattened with a moisture meter connected to the method of measuring the moisture of the blended raw material of the sintering machine comprising:

In the manufacturing method of the sintered ore which mixes a raw material by correcting the amount of water in a mixer, while measuring the moisture content of the blended raw material discharged from a mixer,

Setting a target moisture content of the blended raw material in advance, and obtaining a relationship between the water increase and decrease in the main ingredient increase and decrease in the blending raw material in a mixer;

Measuring the moisture content of the blended raw material discharged from the mixer in actual operation by the method of claim 1;

Calculating the amount of water increase and decrease by comparing the measured amount of water in the blended raw material with the target amount of water;

Calculating the increase and decrease in water by substituting the water increase and decrease amount calculated as described above into the relationship between the increase and decrease in water in the blended raw material;

A method for mixing a blended raw material comprising a step of mixing the blended raw material while correcting by the amount of increase and decrease of the main water obtained in the above blended raw material to the technical gist.

Sinterer, Mixer, Main Water, Moisture Meter, Sintered Ore

Description

Method for measuring the moisture content of blended raw materials and blending method of sintered raw materials using the same {Method for measuring moisture constant in blending raw material and method for blending raw material by using it}

1 is a manufacturing process diagram of sintered ore

Figure 2 is a schematic view of the installation of measuring the moisture content of the blended raw material according to a conventional method

       Fig. 2 (a) is a perspective view and Fig. 2 (b) is a side view.

3 is a schematic view of a facility for measuring the moisture content of the blended raw material according to the present invention

       Fig. 3 (a) is a perspective view and Fig. 3 (b) is a side view.

       * Description of the symbols for the main parts of the drawings *

             1 ..... Raw material storage tank 2 ..... Mixer

             20 .... Moisture meter 31 ....

             33 ..... pressed roller 35 ..... hinge shaft

The present invention relates to a method for producing a sintered ore by measuring the water content of the blended raw material discharged from the mixer of the sintering equipment by adjusting the amount of water in the mixer, and more specifically, measuring both the inside and the surface of the blended raw material In addition, the method of accurately measuring the moisture content of the blended raw material by keeping the distance between the moisture meter and the surface layer of the blended raw material and also in the blending method in the mixer which can improve the productivity and strength of the sintered ore using this method It is about.

The sintered ore used as the main raw material in the blast furnace is iron ore (magnetite, hematite, brown iron ore), secondary raw materials (limestone, silica sand, serpentine, quicklime) and fuel (coke), which are the main raw materials contained in the raw material storage tank 1 as shown in FIG. After blending in the mixer (2), it is manufactured through a sintering process in a sintering machine.

In FIG. 1, reference numeral 3 is an upper light storage tank, 4 is a dust collector, 5 is a main exhaust fan, 6 is a compound material major, 9 is a crusher, and 10 is a cooler.

The raw material particle size used to manufacture the sintered ore is 0.125 to 10 mm and has 2.5 to 3% of its own moisture. Therefore, water is added in the mixer to attach the fine particles to the nucleus particles to form pseudo particles, wherein the amount of water affects the voids of the blended raw material discharged from the mixer. The voids in the blended raw materials are important factors in operation such as improving the air permeability during firing and improving the temperature gradient through heat transfer in the sintered bed to prevent thermal efficiency and inhalation of particulate particles in the sintered tank bogie. Therefore, control of the amount of main water in the blended raw materials in the mixer is important.

In the mixer, the main water content is set in advance in the target moisture content of the blended raw material, and the water content of the blended raw material discharged from the mixer onto the conveyor belt in accordance with the target water content in the actual operation, the moisture meter 20 shown in FIG. The measured amount of water is compared with the target water content to correct the main water supply.

In FIG. 2, reference numeral 22 denotes a conveyor belt, 24 denotes a moisture measuring device fixed shaft, and 26 denotes a support of the moisture fixing shaft.

In addition, there is a method of correcting the moisture content based on the loading amount of the blended raw material, which is used when more than 7.5% of the content of the blended raw material imported due to heavy rainfall caused by meteorological fluctuations and when an error occurs in the moisture meter. This is the way to use it.

As such, the moisture management of the blended raw materials is thoroughly managed as the most important basic management item in the sintering industry, but in practice, the water content of the blended raw materials frequently changes. This is mainly caused by the detection error of the moisture meter.

Moisture meter that detects moisture in blended raw materials absorbs infrared rays from specific wavelengths of water contained in blended raw materials in a near-infrared method and measures the moisture contained in blended raw materials continuously by non-contact reflection at a distance of 300-350mm to reduce the error range. You can. Although there are some detectors that measure moisture by the neutron method, near-infrared moisture meters are widely used because they have a small range of moisture measurement deviation and are convenient in terms of sultry management.

As such, the near-infrared moisture meter can maintain the measurement error within 0.3% only when the measurement distance is maintained at 300 to 350 mm. If the raw material is normally discharged from the mixer at 801 to 850 T / H, there is no significant change in the measurement distance.However, if the emission is changed to 700 to 950 T / H due to increased production, the measurement distance is changed to 200 to 500 mm, resulting in measurement error. Done. In addition, during the transfer of the blended material, the surface is partially dried, and the error range is increased to 1.0 to 1.6%. In particular, when the conveyor belt is stopped, the surface is dried and the measurement error is increased to 2 to 3%. There is a problem done.

This measurement error is that the moisture meter is fixed as shown in Figure 2 does not actively cope with the fluctuation of the compounding material layer, and also, the surface of the compounding material layer is not uniform due to the wave phenomenon as shown in Figure 2 (b) This is because only the surface of the blended raw material layer is measured.

Table 1 shows the moisture content measured according to the change in the loading of the blended raw material when the moisture is measured by a conventional method for the case of the actual blended raw water content of 6.7 to 7.0%.

Emissions of Blended Material from Mixer (T / H) Distance of the moisture meter from the surface of the blended material (mm) Moisture content (%) of blended raw materials measured 700-750 430-500 7.2 to 7.7 751-800 350-430 6.9 to 7.4 801-850 300-350 6.7 to 7.0 851-900 250-300 6.5 to 6.8 901-950 200-250 5.8 to 6.6

As can be seen from Table 1, when the distance of the moisture meter from the compounding material layer exceeds 350mm, the water content of the compounding material to be measured is higher than the actual amount, reducing the amount of main water in the mixer, and conversely, the distance of the water meter is 300mm. If it is shorter than, the water content of the blended raw material will be lower than it actually is, increasing the main water in the mixer. As a result, the moisture content of the blended raw material deviates from the target value so that not only the strength of the sintered ore but also the productivity decreases.

If the moisture content of the blended raw material is not managed, it leads to deterioration of operation. Therefore, when the measuring distance of the moisture measuring device changes due to the change of the discharge amount in the mixer, the method of adding water arbitrarily is experienced by the operator's experience. Since this method does not manage the moisture of the blended raw materials accurately and reproducibly, it reduces the granulation power of the raw materials in the mixer, reduces the thermal efficiency due to the deterioration of the air permeability in the sintering tank bogie, and also deteriorates the quality of the sintered ore and decreases the productivity. It is a factor.

Accordingly, the present invention provides a method capable of accurately and reproducibly measuring the moisture content of a blended raw material while actively coping with a change in the layer height of the blended raw material discharged from the mixer.

Furthermore, the present invention also aims to provide a mixing method in a mixer which can improve the productivity and strength of the sintered ore using this moisture measuring method.

In the moisture measuring method of the present invention for achieving the above object, in the method for measuring the moisture content of the blended raw material discharged from the mixer of the sintering equipment and conveyed on the conveyor belt,

Continuously exposing a predetermined amount of the compounding material in the compounding material layer transferred on the conveyor belt to the surface;

The pressing roller connected to one side of the hinge shaft is made to contact the surface of the blending material to flatten the blending material so that the eccentric load acts on the hinge shaft installed on the conveyor belt, and is integrated at the rear of the pressing roller (along the material feeding direction). It is configured to include; measuring the water content of the flattened blended raw material with a moisture meter connected to.

Furthermore, the blending method of the sintered raw material in the mixer of the present invention is a method of manufacturing a sintered ore in which the raw material is mixed in the mixer by mixing the raw materials while measuring the moisture content of the blended raw material discharged from the mixer,

Setting a target moisture content of the blended raw material in advance, and obtaining a relationship between the water increase and decrease in the main ingredient increase and decrease in the blending raw material in a mixer;

Measuring the moisture content of the blended raw material discharged from the mixer in actual operation by the method of claim 1;

Calculating the amount of water increase and decrease by comparing the measured amount of water in the blended raw material with the target amount of water;

Calculating the increase and decrease in water by substituting the water increase and decrease amount calculated as described above into the relationship between the increase and decrease in water in the blended raw material;

Comprising a step of mixing the blended raw material while pouring in the blended raw material by correcting the amount of increase and decrease of the obtained main water.

Hereinafter, the present invention will be described in detail.

[Measuring Method of Moisture of Blended Raw Material]

The moisture measurement method of the present invention will be described with reference to FIG.

In the present invention, a predetermined amount of the compounding material in the compounding material layer, which is discharged from the mixer 2 and loaded on the conveyor belt, is continuously exposed to the surface. This is to measure the inside and the surface layer of the blended raw material to prevent measurement errors due to drying of the blended raw material layer surface. Exposing the inner compounding material to the surface is possible by providing a plurality of drags 31 on the outlet side of the mixer so that the end portion is inserted into the compounding material layer.

Subsequently, the water content of the blended raw material is measured while the surface of the blended raw material is planarized while actively responding to the height change of the blended raw material layer. This is done by installing the water detection device 30 shown as an example in FIG. 3 at the rear of the dragger 31 (along the raw material transfer direction).

Moisture detection device 30 of the present invention,

The hinge shaft 35 is installed on the conveyor belt 22 in the width direction and allows one side and the other side to move up and down.

A pressing roller 33 connected to one side of the hinge shaft such that an eccentric load acts on the hinge shaft to flatten the surface of the blended raw material;

It is composed of a moisture measuring device 20 which is integrally connected to the rear of the pressing roller (along the raw material conveying direction) to measure the moisture content of the blended raw material.

The hinge shaft 35 is connected to the bearing block 36 on the support 34 located on both sides of the conveyor belt. The connecting bar 38 extends to both sides at both ends of the hinge shaft, and the pressing roller 33 is connected to one end of the connecting bar 38. In the present invention, the pressing roller 33 has an eccentric load acting on the hinge shaft 35 to interview the surface of the blending raw material. In this case, when the pressing roller is to adjust the force acting on the blending raw material, The weight 37 may be provided.

The rear of the pressing roller 330 is integrally formed with a moisture meter 20, the moisture meter 20 may be connected to the connecting bar between the hinge axis and the pressing roller, to the support bar 39 of the pressing roller In any case, the moisture meter is preferably installed close to the press roller.

By using the moisture detection device constructed in accordance with the present invention, the pressing roller 33 flattens the surface of the blended raw material, so that the surface layer prevents measurement error due to wave phenomenon. In addition, since the moisture meter and the pressing roller are integrally operated with respect to the hinge axis, even if the height of the compounding material layer changes due to the change of the discharge amount in the mixer, the moisture content of the compounding material is kept while keeping a certain distance in response to the change of the compounding material layer. It can be measured. Moisture meter is most preferably to maintain a distance of 300 ~ 350mm with the compounding material layer, the moisture meter should be installed 300 ~ 350mm away from the contact roller and the compounding material layer. Most preferably 325 mm.

As described above, the surface of the compounding material layer is flattened by the pressing roller, and the moisture measuring device maintains a distance of 300 to 325 mm from the surface of the compounding material layer, so that the measurement error can be maintained within 0.3%.

[Method of Mixing Raw Material in Mixer]

The raw material blending method in the mixer using the moisture measuring method of the blended raw materials, first set the target moisture content of the blended raw materials to 6.7 to 7.0%, which is set in consideration of the productivity and the strength of the sintered ore. That is, in order to form a proper void in the blended raw material, the moisture content of the blended raw material should be 6.7% or more. If the moisture content of the blended raw material exceeds 7.0%, the water content of the blended raw material is too high and the voids of the blended raw material particles are filled with water. Breathability in the sinter tank bogie is deteriorated. In addition, since the heat transferred from the upper portion is consumed for moisture evaporation, heat is not transferred to the lower layer, and a very high wet zone is formed in the lower layer portion in the sintering tank trolley, so that the plastic state and breathability are extremely deteriorated.

In addition, operation data of the main water increase and decrease required for the water increase and decrease of the blended raw materials in the mixer is obtained. For example, when the addition water introduced at a pressure of 5 to 6 kg / cm 2 is supplied with a water content of ± 0.3 to 0.40 kg / T when the opening degree of the flow controller is operated to be ± 1 to 2%, water is added to the mixture raw material ± 0.1. In case of increasing / decreasing%, the required increase / decrease amount is 0.8 ~ 1.0kg / T.

The actual operation is performed with the above operation data. First, the mixture is mixed with water so that the target water content of the blended raw material is contained in the blender, and then the blended raw material is discharged onto the conveyor belt. The moisture content of the blended raw material discharged from the mixer is measured by the method of measuring the moisture of the blended raw material of the present invention.

The amount of moisture increase and decrease of the blended raw material is calculated by comparing the measured moisture content of the blended raw material with 6.0 to 7.0% of the target moisture content. The calculated amount of water increase and decrease is obtained by substituting the calculated amount of water increase and decrease into the operation data of the number of increase and decrease of water required for the water increase and decrease.

This main water increase and decrease is corrected to the main water amount of the mixer and mixed with the raw material while pouring it into the raw material.

Hereinafter, the present invention will be described in more detail with reference to Examples.

Example 1

In the mixer of large sintering equipment with an effective image area of 430㎡, the raw materials are mixed in the main quantity of 21-28kg / T and discharged on the conveyor belt at 700-950T / H, so that the moisture content of the blended raw materials is 6.7-7.0%. While sintering ore was prepared. At this time, the measured moisture value and the distance between the moisture meter and the surface layer were measured while measuring the moisture of the blended raw materials according to the present invention and the conventional method.

division Compound material emissions from the mixer (ton / H) Moisture Meter Distance between Moisture Meter and Compound Raw Material Surface Layer Conventional Example 1 851-950 5.8 to 6.6 250-300 Conventional Example 2 751-800 6.9 to 7.4 350-430 Conventional Example 3 700-750 7.2 to 7.5 430-500 Conventional Example 4 801-850 6.7 to 7.7 300-350 Inventive Example 1 851-900 6.7 to 7.0 310 to 350 Inventive Example 2 751-800 6.6-7.0 300-340 Inventive Example 3 700-750 6.8 to 7.1 320 to 350 Inventive Example 4 801-850 6.7 to 7.0 300-350

As can be seen from Table 2, the conventional method maintains the measurement distance of the moisture meter in the range of 200 to 500 mm in accordance with the change of the amount of the blended raw material in the mixer, and the measurement of the moisture meter is 6.0 to 7.5%, 0.5 to 0.7%. Large deviations occurred. In contrast, in the case of the example of the present invention, even if the discharge amount of the blended raw material was varied, the moisture measurement distance was maintained at 300 to 350 mm, and the measurement value of the moisture meter was set at 6.0 to 7.0%, so that no error occurred.

Example 2

In the mixer of large sintering equipment with an effective image area of 430㎡, the raw materials are mixed in the main quantity of 21-28kg / T and discharged on the conveyor belt at 700-950T / H, so that the moisture content of the blended raw materials is 6.7-7.0%. While sintering ore was prepared. At this time, the sintering machine speed was 3.0-3.5 m / min, and productivity maintained 32.0-34.5 T / D / m <2>.

division Actual moisture of blended raw materials (%) Moisture measured by moisture meter (%) Main quantity (kg / Ton) Blended raw material Productivity (T / D / ㎡) burglar (%) Sintered light intensity -10mm (%) + 5mm -0.125mm Conventional Example 1 7.4 to 7.7 5.8 to 6.3 27.1 to 29.1 12.8-13.4 8.8 to 9.5 32.0 to 33.5 90.0 to 91.0 37-40 Conventional Example 2 7.0 to 7.3 6.4 to 6.6 24.6-26.6 12.4 to 13.0 9.5 to 10.0 33.5 to 34.0 91.0 to 91.5 35 to 37 Inventive Example 1 6.7 to 7.0 6.7 to 7.0 22.1 to 24.1 12.0-12.5 10.0 to 10.5 34.0 to 34.5 91.5 to 92.0 34-36 Conventional Example 3 6.3 to 6.7 7.1 to 7.3 19.6 to 21.6 11.0 to 12.0 10.5 to 12.0 33.2-34.0 91.0 to 91.6 36-38 Conventional Example 4 5.8 to 6.3 7.4-7.8 16.3-18.3 9.0-11.5 12.0 to 13.0 32.0 to 33.3 90.0 to 90.5 38-41

As shown in Table 2, when the moisture content of the blended raw material is increased, the blended raw material is not mixed well in the mixer, and the primary and secondary raw materials are excessively assembled due to the occurrence of unbalanced phenomenon and the stress action of water. There is no gap in between. That is, in the conventional example (1-2), the productivity is 1.5-2.0T / D / m2 due to the deterioration of air permeability due to the + 5mm increase of 0.8-1.5% and the decrease of -0.125mm of 1.0-1.2% compared to the invention example (1). Of course, the strength was reduced by 1.0-1.5%.

On the contrary, in the case of the conventional examples (3 to 4) in which the moisture content of the blended material is lower than 6.7%, the water content is too small and the stress action of the water is reduced in the mixer. In order to deteriorate the dust collection capacity, the thermal efficiency deteriorates due to poor heat transfer during combustion of the fuel during firing, and thus the plastic bond is not formed. Occurred. For this reason, the conventional example (3-4) has a decrease in granulation capacity due to a decrease in the moisture content of the blended raw materials, and thus the water content +5 mm is reduced by 1 to 3%, -0.125 mm is increased by 2 to 2.5%, and the granularity is increased. Productivity decreased by 2 ~ 2.2T / D / m2, and the strength of sintered ore deteriorated to 1.5 ~ 2.0% due to deterioration of air permeability during firing due to a decrease in capacity.

On the other hand, in the present invention, the target moisture content is set to 6.7 to 7.0% in advance, and as a result of determining the relationship between the increase and decrease of water content, the increase and decrease of water consumption is 0.8 to 1.0 kg / T with respect to the water increase and decrease of ± 0.1%. Data was obtained. Therefore, the moisture content of the blended raw material is measured within the target moisture as a result of measuring the water content of the blended raw material according to the present invention and correcting the main water content in consideration of the relationship obtained above when the measured moisture content is different from the target water content. Could be adjusted.

As described above, the present invention is capable of mixing the moisture content effective for operation in the mixer by measuring the measurement range of the moisture meter at a distance without an error range, regardless of the discharge amount of the blended raw material in the mixer. Increasing and improving the breathability and sintering state when charging the raw material in the balance of the sintering machine has a useful effect of producing a sintered ore with excellent productivity and quality of the sintered ore.

Claims (4)

In the method of measuring the moisture content of the blended raw material discharged from the mixer of the sintering equipment and conveyed on the conveyor belt, Continuously exposing a predetermined amount of the compounding material in the compounding material layer transferred on the conveyor belt to the surface; The pressing roller 33 connected to one side of the hinge shaft contacts the surface of the blending material to flatten the blending material so that the eccentric load acts on the hinge shaft 35 installed on the conveyor belt, and rearwards the pressing roller 33. Measuring the moisture content of the blended raw material comprising a; measuring the water content of the blended raw material flattened by a moisture meter (20) integrally connected to (in the raw material transfer direction). In the manufacturing method of the sintered ore which mixes raw materials by correcting the amount of main water in the mixer while measuring the moisture content of the blended raw materials discharged from the mixer, Setting a target moisture content of the blended raw material in advance, and obtaining a relationship between the water increase and decrease in the main ingredient increase and decrease in the blending raw material in a mixer; Measuring the moisture content of the blended raw material discharged from the mixer in actual operation by the method of claim 1; Calculating the amount of water increase and decrease by comparing the measured amount of water in the blended raw material with the target amount of water; Calculating the increase and decrease in water by substituting the water increase and decrease amount calculated as described above into the relationship between the increase and decrease in water in the blended raw material; Mixing the blending raw materials while correcting the amount of the increase and decrease of the obtained main water and pouring the blending raw materials. The method of blending sintered raw materials according to claim 2, wherein the target moisture content of the blended raw materials is 6.7 to 7.0%. The sintering method according to claim 1 or 2, wherein the relation between the increase and decrease in water content of the blended raw material is 0.8 to 1.0 kg / T with respect to the increase or decrease in water content of ± 0.1%. Blending method of raw materials.

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