KR19990013132A - Sintered Ore Manufacturing Method - Google Patents

Abstract

The present invention relates to a method for producing a sintered ore used as a blast furnace raw material, the particle used as the bottom light to effectively prevent the loss of raw materials and cope with fusion and light distribution in the gap between the large bar when charging the blending raw material sintering machine (1) Method for producing iron ore sintered ore that can increase the air permeability and improve productivity by distributing segregation in the raw material in the bed through the drum-type grain-light extractor (4) through the grain-shaped storage tank (3) sized from 8 to 13 mm to be.

The present invention has been a problem in improving the sintering productivity by effectively reducing the density of the water staging zone that forms the negative pressure until the light distribution is completed by the raw material loading and the grained light mixing and cutting device in the method of manufacturing the suction sintered ore suction downward The negative pressure is drastically lowered, and the method for producing iron ore sintered ore is the main point.

Description

Sintered ore manufacturing method

The present invention relates to a method for producing a sintered ore that is used as a blast furnace raw material.

In general, the sintered ore is manufactured by mixing a variety of iron ore as a main raw material, limestone, silica sand and serpentine as a main raw material, and powdered buncoke as a fuel in a first mixer and adding a suitable moisture, as shown in FIG. 1. It is granulated in the granulator, charged into the sintering machine, and the surface is ignited at 1200 ° C. in the ignition furnace 7, and then the outside air is sucked by the main blower 11 below the sintering machine to burn the coke as fuel. By the temperature rises to 1300 ~ 1400 ℃ by sintered body having a strong bonding force between the particles is completed is completed.

The sintering operation should satisfy the target output and quality, but the relationship between output and quality tends to be in opposition, so that each characteristic value can be maintained in the existing process control system to maintain the optimum quality while achieving the target output. It is managed by (Process Pontrol System) and Distribution Control System.

However, the method of improving the sintering productivity includes increasing the amount of raw materials charged per unit area at the sintering speed, that is, raising the layer thickness of the blended raw materials loaded on the sintering machine to maintain the yield and the quality. Increasing aeration resistance in the product improves the quality and recovery rate, but decreases the quantity of production. Therefore, advanced technology is needed to manage both production and quality upwards in terms of production and quality.

The present invention was devised to solve the above problems, the high productivity sintered ore manufacturing method that can increase the air permeability in the sintering machine bogie (1) bed having a large impact on the sintered ore productivity and quality and improve productivity The purpose is to provide.

1 is a process chart showing a D.L type sintered ore manufacturing process.

Figure 2 is a schematic diagram of a sintering reaction state in a conventional sintering machine.

3 is a perspective view showing an embodiment according to the present invention.

4 is a signal flow diagram for explaining the operation of the present invention.

5 is a graph of the time (F.F.S) the sintered ore is prepared before, after the implementation of the present invention.

Figure 6 is a graph showing the productivity and quality changes of sintered ore according to the amount of grain size of the present invention.

7 is a graph showing the productivity relationship of the sintered ore according to the amount of charged grain of the present invention.

8 is a graph showing the quality relationship of the sintered ore according to the amount of charged grain of the present invention.

Explanation of symbols on the main parts of the drawings

1: Sintering machine pallet

2: Surge hopper

3: hearth layer hopper

4: drum type feeder

5: angle light plate

6: upright light guide plate angle adjuster (screw jack)

7: ignition hood

8: slope controller

9: drum feeder

10: raw material inclination plate

11 main blower

12: wind box

13: load cell

Hereinafter, a sintered ore manufacturing method according to the present invention will be described in detail with reference to the accompanying drawings.

1 and 2 illustrate a DL continuous sintering machine that is easy to automate mass production and operation, and includes a compound raw material storage tank 2, a grained light storage tank 3, a post-layer detection rod 8, a drum-type raw material extruder ( 9) and a charging device and an ignition device 7 composed of a raw material inclined guide plate 10 are installed in a fixed position, and a continuous sintering machine pallet 1 is mounted on a drive sprocket wheel (not shown). The raw materials are charged into the moving sintering machine trolley 1 and ignited, and the calcined ore is discharged while sucking and sintering and inverting air from under the grate.

FIG. 3 shows a sintering reaction state occurring in a sintering machine within an effective burn distance of 100 m and appears in several reaction zones in a bed during sintering, which is roughly classified into a water condensation zone 14 and a combustion zone 17. ), A cooling zone 15, which is an initial region that maintains the same moisture content as the blended raw material and a moisture content region above the critical moisture content, and propagates to the entire sintered layer within 3 minutes after surface ignition of the sintered fuel to maintain a constant moisture content. (14), and the hot and humid inlet air flowing from the upper layer passes through the raw material layer, releasing moisture contained below the dew point into the raw material layer to be below the critical moisture content, and overheated by coke combustion. Combustion zone in which ore is melted into reaction zones such as coke and limestone in which free water adhered to the particle surface by exhaust gas is evaporated. 17) and the cooling stand which is solidified to form a cake (C 15), and the amount of water condensation zone 14 in the first half of the sintering increases and decreases the sintering productivity and breathability. By absorbing these problems it can be seen that the ventilation is improved.

Referring to FIG. 2, the blended raw material transported to the raw material storage tank 2 by the charging method according to the conventional sintered ore manufacturing method is a simple angle of repose (58 °) after the sintering machine bogie 1 is layered by the drum type cutting machine 9. The amount of raw material charged by the post-layer detection rod 8 is determined while charging is performed, and the present invention is carried out before the compounded raw material charged by the method of establishing the compounding material layer and selecting charging method in the existing equipment before reaching the ignition furnace 7. Through the drum-shaped grain-light cutting machine (4) below the grain-light storage tank (3), the amount of grain light cutting is proportionally cut out to 0-15% of the amount of raw material cutting. By mixing and mixing the grain light to effectively remove the first half of the water condensate 14 from the water, the granulated grain is uniformly distributed in the bottom 300mm of the sintering machine trolley (1). Condenser By technically absorbing the evaporation of the water serves to suppress the recondensation phenomenon in the lower layer.

The present invention will be described in more detail with reference to examples.

EXAMPLE

The compounding charged in the bed in the sintering machine trolley 1 according to the present invention and the conventional method controlled by the angle of repose naturally obtained by the induction of the raw material inclined guide plate 10 when charging the raw material in the sintering machine trolley 1. The sintering machine (8 ~ 13mm) sintered granules (8 ~ 13mm) sintered in the raw material layer is added by the drum type sintering machine (4) to add 2 ~ 10% of the grains in the amount of the raw materials. The temperature change of the sintered raw material layer was observed by selective charging so as to distribute 300 mm from the bottom of the trolley | bogie in the trolley width direction, and the result is shown in the graph of FIG.

As shown in FIG. 4, the time for which the sintered ore is manufactured is represented by the flame front speed of the sintered ore manufacturing process, in which the raw material charged in the sintering machine trolley 1 undergoes surface ignition and the sintering trolley 1 proceeds. In the process of being sintered by the main blower 11 which sucks downward, it becomes an important factor in the production of sintered ore.

If the sintering time, ie, the sintering speed (ffs) is fast, the transpiration is increased, but if it is too fast, the time is shorter than the maximum temperature, and the drop strength (Shatter Index) and the recovery rate are lowered, so that a reduction effect is obtained (# 24 in FIG. 3). The curve is gentle and the highest achieved temperature is low (# 20 in Fig. 3). When the sintering speed (ffs) is constant, the highest temperature point (btp) in the bed is shown in the sinterer bogie (1) bed as shown in the curve of Fig. 4. If the sintered ore is quenched on the sintering machine trolley 1, the quality is poor. If the sintering machine trolley 1 is too fast, BTP (Burn Through Point sintered ore firing completion point) as shown in ⓒ of FIG. Since the light distribution is not performed and sintering before the formation of), the operation is performed to slow the bogie speed to become the ⓑ curve of FIG. 4.

The embodiment of the present invention was automatically operated by a process control system in order to maintain a constant sintering machine speed, and accordingly, in the method of manufacturing high productivity sintered ore by the step-by-step configuration device, the sintered ore sintered at 8 to 13 mm was transported. The first collecting step of transporting to the reservoir 3, and the appropriate height in the bed of the sintering machine trolley (1) from the first collecting step to the sizing light guide plate angle adjuster 6 installed in the sizing guide plate 5 A third change amount calculated to determine the required amount of the grained light of the present invention according to the operation situation on the basis of the second layer adjustment step of adjusting the height by the step and the amount of charge determined at the time of cutting the conventional blended raw materials from the first and second steps. A step of detecting an alarm to a control room worker through a distributed control system (DCS) by detecting whether the difference cut out from the calculation step and the third change amount calculation step is within an allowable value In the present invention characterized by consisting of four sensing step was to reduce the moisture condensing band effect on the sintering intra-layer air permeability in order to improve the productivity.

Sintering raw materials added with water sintering as the combustion zone of the narrow width moves to the lower part of the bed after ignition.

At this time, the raw material layer is preheated by hot gas at the front end of the combustion zone at 1200 to 1400 ° C., and thus a dry layer is formed. Moisture moving from the condensate is formed at a temperature where the temperature drops below the dew point of the gas to form a water condensation zone.

This moisture stand usually ends at a temperature that reaches the dew point of the gas between 55 and 65 ° C. Moisture of the moisture measuring zone deteriorates the air permeability of the raw material layer during the sintering process, so that the optimum amount of moisture is generally controlled lower than the amount of moisture that provides the best ventilation before ignition, and the moisture measuring zone is controlled at the sinter hole (12) # 9, 10. According to the results of the water survey, the water content of the raw material was 7.5% and 8.0%, respectively, compared with the water content of 5.8%.

This moisture content can be said to start the destruction of the pseudo particles, reducing the porosity in the layer and cause air resistance. Therefore, in order to minimize the impact on the operation by using the sintered mineral mixture, the results of the mixing raw materials with the same conditions as the other raw materials and the change of the obesity of the sintered mineral mixing were investigated. Raw materials and preparation conditions are shown in Table 1 below.

TABLE 1

Reference Table for Compound Raw Material for Sintering Operations According to Examples

In the sintering productivity according to the use of the grained light mixture, the yield recovery rate decreases as the composition of the quicklime mixture and the grain size of the layer are increased under a constant state after the layer formation (FIG. 6a). (FIG. 6b)

The reason for the increase in productivity is that even though the grain size of the blended raw material is increased due to the increase in the use ratio of the grain light (FIG. 6c), the air permeability in the sintering bed is improved (FIG. 5d), thereby improving the advancing speed (ffs) of the sintering machine. It turns out that the width | variety of productivity is larger than productivity fall range in the fall of a recovery rate.

In addition to the above operating conditions, the fuel ratio is within the range of 3.71 to 3.77% in order to more clearly understand the sintered ore quality fluctuations when the use of the grained light mixture according to the layered grained light mixing of the present invention is 3-7%. Analyzing the average working data for each shift (8 hours), the fraction (-10mm) and the drop strength (si) have little effect as the upright light ratio increases as shown in a, b, and c of FIG. Can be.

This increases the air permeability in the same bed it can be seen that the holding time at a high temperature (1300 ℃) is relatively reduced to reduce the occurrence of the bonding slag (Bonding Slag) to have a strong binding force at room temperature.

However, the reduction of the high temperature holding time plays a role of shortening the time for generation of secondary hematite (Fe ₂ O ₃ ), which causes RDI deterioration, so that the reduction differentiation strength (RDI) is further improved at 3-7% of the grain size mixing. .

Therefore, in the bed of the granulated granules used in the present invention, it was found that the effects of the present invention were shown to be greatest when 3 to 7% was used as shown in the graph shown in FIG. It can be seen that the improvement is 15 ~ 23% without change.

As described above, according to the sintered ore manufacturing method according to the present invention, the effect of improving the sintering productivity by effectively reducing the density of the water condensation zone which is completed firing from the raw material loading and the grained light mixing and cutting device to form the negative pressure until light distribution without deterioration of quality. There is.

Claims (1)

A collecting step of transporting the sintered ore sintered at 8 to 13 mm and transporting it to the sintering light storage tank 3, and the sintering light installed at the sintering guide plate 5 at an appropriate height in the bed of the sintering machine trolley 1 from the collecting step. Floor-level adjustment step of adjusting the height by the guide plate angle adjuster (6), A change amount calculation step of calculating the amount of grain light to be determined according to the operation situation based on the amount of charge determined at the time of cutting the blended raw materials from the collection step and the adjustment of each layer; And a sensing step of detecting whether a difference cut out from the change calculation step is within an allowable value and notifying an alarm to a control room worker through a distributed control system (D.C.S).