A sintering machine and a method for improving the sintering yield

Abstract

The present invention discloses a sintering machine and a method for improving the sintering finished product rate. A dust bin is added to the existing sintering process, and at the same time, a dust spreader is added. A layer of dust with a high carbon content is arranged behind the sintering ignition. Due to the negative pressure effect, the fine dust is sucked into the sintering material layer together with the wind and burns to supply heat in the combustion layer, promoting sintering. In the sintering process of the present invention, dust is laid, and the wind box sucks the dust downward to fill the voids in the filler layer, especially at the edge of the sintering trolley, reducing the phenomenon of uneven air extraction in the cross section. The carbon content in the dust is greater than 20%, increasing the heat in the sintering process of the upper layer of the sintering material, promoting the agglomeration of the upper layer of the sintering material, and improving the finished product rate.

Description

Technical Field

[0001] The present invention relates to the technical field of sintering, and particularly to a sintering machine and a method for improving the sintering yield. Background Art

[0002] Sinter is the main iron-containing raw material in the iron-making process of iron and steel enterprises, accounting for about 70%. The sintering process not only produces sinter for iron-making, but also treats various iron-containing dusts and sludge and other wastes of iron and steel enterprises. Sintering is to proportionally add and mix various powdered iron-containing raw materials with fuel, flux and water, mix and granulate on a mixer, spread it on a sintering machine, ignite from the upper part and draw air from the lower part, and sinter from top to bottom. When sintering, the fuel burns to release heat, forming a high temperature, which promotes a series of physical and chemical reactions. Some fusible substances in the mixture soften and melt to produce a certain amount of liquid phase, which wets and binds the surrounding ore powder particles. When the fuel is exhausted and the temperature drops, the liquid phase solidifies to form a porous product with a certain strength, which is called sinter.

[0003] The sintering process starts from the surface of the material layer and gradually proceeds downward, so there is an obvious stratification phenomenon along the height of the material layer. The sintering material layer is divided into five layers from top to bottom, namely the sinter layer, the combustion layer, the preheating layer, the drying layer and the over-wet layer. As the sintering trolley moves, the five layers appear and disappear in turn, and finally only the sinter layer remains.

[0004] Currently, most of the dust and sludge in each iron and steel plant are recycled to the sintering raw material yard, mixed with sinter ore powder to form a sintering mixture, and then flux and fuel are added for sintering. In this process, most of the dust with high carbon content is not included in the calculation of sintering fuel when mixed and sintered with the homogenized material, and the fluctuation is also large, resulting in large fluctuations in sintering indexes, which is not conducive to the stability of sintering and iron-making production.

[0005] At the same time, the main reasons for the low sintering yield are mainly the following two aspects: one is that due to insufficient heat and fast cooling on the surface of the sintering material layer, the amount of liquid phase is small, and it is difficult to form blocks on the surface layer, resulting in a low sintering yield. Currently, methods such as extending the ignition time or adding a heat preservation cover after ignition are used to solve this problem. However, the effect is not very good. The other is due to the edge effect, the gap at the edge of the sintering trolley is large, resulting in a large amount of air passing through the edge of the sintering trolley, a short heat preservation time, and it is difficult for the sintering material to form blocks.

[0006] Patent CN105132673B discloses a method for reducing the solid energy consumption of composite agglomeration of carbon-containing and iron-containing dust pellets. This method involves mixing carbon-containing and iron-containing dust with a binder to form pellets; mixing raw materials including iron ore powder, flux, and coke powder to make granules; mixing the obtained pellet materials and granular materials, and successively passing through feeding, ignition, sintering, and cooling to obtain composite agglomerates. By regulating the matching relationship between the combustion of fixed carbon in the dust pellets and the combustion of coke powder in the granular materials, and on this basis, through appropriate feeding, the heat storage effect of the composite agglomerate layer is fully utilized, so that there is sufficient heat in both the upper and lower parts of the sintering material layer to ensure the consolidation strength of the pellet materials and granular materials. However, there are large voids inside the material layer, the sintering temperatures of the sintering raw materials close to the dust pellets and the fillers far from the dust pellets are inconsistent, the sintering of the cross-section of the material layer is uneven, and the sintering yield is low. Summary of the Invention

[0007] In view of the above-mentioned prior art, the object of the present invention is to provide a sintering machine and a method for improving the sintering yield. To achieve the above object, the present invention adopts the following technical solutions:

[0008] The first aspect of the present invention provides a sintering machine, including a sintering trolley, a feeder, an igniter arranged successively along the running direction of the sintering trolley, a wind box located below the sintering trolley, and further including a dust bin and a dust spreader. The dust bin is located downstream of the igniter, the bottom of the dust bin is connected to the top of the dust spreader, and the bottom discharge port of the dust spreader is located above the sintering trolley.

[0009] Preferably, the dust bin is vertically placed and the dust spreader is inclined.

[0010] More preferably, the included angle between the dust spreader and the vertical direction is 30° - 60°.

[0011] Preferably, the distance between the discharge port of the dust spreader and the bottom of the sintering trolley is 900 - 1100 mm, and the horizontal distance between the discharge port of the dust spreader and the igniter is greater than 2 m; the length of the discharge port of the dust spreader is equal to the width of the sintering trolley, and the width of the discharge port of the dust spreader is 3 - 8 cm.

[0012] Preferably, it further includes a crusher at the tail of the sintering trolley, a ring cooler is arranged behind the crusher, a screen is arranged below the ring cooler, the bottom of the wind box is connected to a dust collector through a pipeline, the dust collector is connected to a suction fan through a pipeline, and a base material bin is arranged upstream of the feeder.

[0013] The second aspect of the present invention provides a method for improving the sintering yield by using the above sintering machine, which is characterized by including the following steps:

[0014] The base material bin lays the base material in the sintering trolley, the feeder lays the sintering raw materials above the base material, the sintering trolley runs, the igniter ignites, the dust is collected in the dust bin, the dust spreader conducts dust spreading in the width direction of the sintering trolley, and the air box sucks air under the sintering trolley and sucks the dust into the sintering raw materials.

[0015] Preferably, the cloth thickness of the dust is 10 - 30 mm, and the dust is sucked into the sintering raw materials at 1 / 3 - 1 / 2 of the sintering section. The sintering section is between the sintering ignition and the sintering end point. The sintering end point is judged by the waste gas temperature of the air box under the trolley, and the vicinity of the highest point of the waste gas temperature of the air box is the sintering end point position.

[0016] Preferably, the carbon content of the dust is greater than 20%, and more than 50% of the dust particle size is 200 mesh.

[0017] Preferably, the dust is one or more of blast furnace bag dust and coking environmental dust.

[0018] Preferably, the cloth thickness of the base material is 50 - 60 mm, and the cloth thickness of the sintering raw materials is 800 - 1000 mm.

[0019] The present invention utilizes the characteristics of the sintering process, adds a dust bin and a dust spreader, and distributes the fine dust with high carbon content on the surface of the sintering material layer after sintering ignition, solving the problem of fluctuations in sintering indexes caused by unknown carbon in this part of the dust in the past. At the same time, due to the sintering suction effect, the dust is sucked downward, blocking most of the voids in the material layer, making the cross-section of the material layer sinter more evenly. At the same time, the dust enters the sintering layer, and the carbon in the dust is ignited and burned, providing heat and promoting the formation of sintering liquid phase. On the other hand, the dust is distributed on the surface of the sintering material layer, playing a surface heat preservation role and also being beneficial to improving the sintering yield.

[0020] When the surface of the sintering material layer is ignited and air is sucked in, the combustion zone in the sintering process gradually moves downward along the height of the material layer from the start of sintering. In the upper part of the sintering material layer, due to insufficient heat and surface heat dissipation, the sintering is insufficient, and the upper sintering material cannot form lumps or the strength of the formed lumps is insufficient. The added dust mainly solves the problem of the upper sintering material. Due to the heat storage effect, the heat of the lower sintering material is sufficient. At this time, the upper sintering has been formed and does not need to rely on carbon-containing dust to provide heat. Therefore, the dust only needs to be sucked into the material layer at 1 / 3 - 1 / 2 of the sintering section.

[0021] The beneficial effects of the present invention:

[0022] The present invention lays dust during the sintering process. The air box sucks the dust downward to fill the voids in the material layer, reducing the vertical sintering speed. When the carbon content in the dust is greater than 20%, it increases the heat in the sintering process of the upper sintering material layer, promotes the agglomeration of the upper sintering material, and improves the yield.

[0023] In the present invention, dust is distributed on the surface of the sintering material layer, and a part of the dust is sucked into the material layer by the air box to fill the voids, thereby reducing the uneven air extraction phenomenon in the cross section and improving the sintering yield. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 : Schematic diagram of the sintering material distribution of the present invention;

[0025] Figure 2 : Front view of the dust bin and the dust spreader of the present invention;

[0026] Figure 3 : Left view of the dust bin and the dust spreader of the present invention;

[0027] As shown in the figure: 1. Sintering trolley, 2. Igniter, 3. Dust bin, 4. Dust spreader, 5. Material distributor, 6. Dust collector, 7. Ring cooler, 8. Air box, 9. Crusher, 10. Exhaust fan, 11. Internal space of the sintering trolley, 12. Screen, 13. Discharge port, 14. Bottom material bin. DETAILED DESCRIPTION OF THE INVENTION

[0028] It should be noted that the following detailed description is exemplary and is intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present application belongs.

[0029] As described in the background art, due to insufficient heat, rapid cooling, small amount of liquid phase on the surface of the sintering material layer, it is difficult for the surface layer to form lumps, resulting in low sintering yield. The air volume passing through the edge of the sintering trolley is large, the heat preservation time is short, and it is difficult for the sintering material to form lumps.

[0030] Based on this, the present invention provides a sintering machine, which includes a sintering trolley 1, a material distributor 5 and an igniter 2 arranged in sequence along the running direction of the sintering trolley, a plurality of air boxes 8 located below the sintering trolley, and also includes a dust bin 3 and a dust spreader 4. The dust bin 3 is located downstream of the igniter 2. The dust bin 3 and the dust spreader 4 are cuboids. The dust bin 3 is placed vertically, the dust spreader 4 is placed obliquely, and the angle between the dust spreader 4 and the vertical direction is 30° - 60°. The bottom of the dust bin 3 is connected to the top of the dust spreader 4. The distance between the discharge port 13 of the dust spreader 4 and the bottom of the sintering trolley 1 is 900 - 1100 mm, and the horizontal distance between the discharge port 13 of the dust spreader 4 and the igniter 2 is greater than 2 m; the length of the discharge port 13 of the dust spreader 4 is equal to the width of the sintering trolley 1, and the width of the discharge port 13 of the dust spreader 4 is 3 - 8 cm.

[0031] It also includes a crusher 9 located at the tail of the sintering trolley. A ring cooler 7 is provided behind the crusher. A screen 12 is provided below the ring cooler 7. The bottom of the air box 8 is connected to a dust collector 6 through a pipeline. The dust collector 6 is connected to a suction fan 10 through a pipeline. A base material bin 14 is provided upstream of the feeder 5.

[0032] Using the base material bin 14, sintered ore is laid as the base material in the sintering trolley 1 to form a base material layer with a thickness of 50 - 60 mm. The sintering raw materials are evenly laid above the base material by the feeder 5 to form a sintering material layer with a thickness of 800 - 1000 mm. The igniter 2 ignites. Dust with a carbon content greater than 20% and a particle size of 200 mesh for more than 50% is collected in the dust bin 3. The dust spreader 4 conducts dust spreading in the width direction of the sintering trolley 1, and the dust is evenly sprayed on the surface of the sintering raw materials. The thickness of the dust spreading is 10 - 30 mm. Under the action of the suction fan 10, the air box 8 sucks the dust into the sintering material layer. According to the position of the sintering end point, the thickness of the dust spreading is adjusted so that the dust is sucked into the material layer at 1 / 3 - 1 / 2 of the sintering section. After the dust and the material layer are sintered, sintered ore is formed. The sintered ore enters the crusher 9 at the tail of the sintering trolley 1 for crushing and then enters the ring cooler 7 for cooling. The screen 12 screens the crushed sintered ore and then enters the blast furnace for the next process.

[0033] In order to enable those skilled in the art to more clearly understand the technical solution of this application, the technical solution of this application will be described in detail below in conjunction with specific embodiments.

[0034] The test materials used in the embodiments of the present invention are all conventional test materials in the art and can be obtained through commercial channels.

[0035] Embodiment 1

[0036] A sintering machine includes a sintering trolley 1, a base material bin 14, a feeder 5, and an igniter 2 arranged in sequence along the running direction of the sintering trolley. A number of air boxes 8 are located below the sintering trolley. It also includes a dust bin 3 and a dust spreader 4. The dust bin 3 is located downstream of the igniter 2. The dust bin 3 and the dust spreader 4 are cuboids. The dust bin 3 is placed vertically, and the dust spreader 4 is placed obliquely. The included angle between the dust spreader 4 and the vertical direction is 45°. The bottom of the dust bin 3 is connected to the top of the dust spreader 4. The distance between the discharge port 13 of the dust spreader 4 and the bottom of the sintering trolley 1 is 900 mm. The horizontal distance between the discharge port 13 of the dust spreader 4 and the igniter 2 is greater than 2 m. The length of the discharge port 13 of the dust spreader 4 is equal to the width of the sintering trolley 1, and the width of the discharge port 13 of the dust spreader 4 is 5 cm.

[0037] Using the base material bin 14, the sintered ore is laid as the base material in the sintering pallet car 1. The sintering raw materials are evenly laid above the base material by the feeder 5. The igniter 2 ignites. The dust with a carbon content greater than 20% and a particle size of 200 mesh or more is collected in the dust bin 3. The dust spreader 4 conducts dust spreading in the width direction of the sintering pallet car 1, and the dust is evenly sprayed on the surface of the sintering raw materials. The air box 8 sucks the dust into the sintering material layer under the action of the induced draft fan 10. According to the position of the sintering end point, the thickness of the dust spreading is adjusted so that the dust is sucked into the material layer at 1 / 3 - 1 / 2 of the sintering section. After the dust and the material layer are sintered, sintered ore is formed. The sintered ore enters the crusher 9 at the tail of the sintering pallet car 1, is crushed, and then enters the annular cooler 7 for cooling. The screen 12 screens the crushed sintered ore and then enters the blast furnace to continue the next process.

[0038] The dust used is blast furnace bag dust, and its composition and particle size composition are as shown in Table 1 below. Now, for a 480m 2 The length of the pallet car of the sintering machine is 96 meters. During normal sintering, the position of the sintering end point fluctuates little, and the length of the sintering section is about 80 meters. The thickness of the base material spreading is 50 mm, and the thickness of the sintering raw material spreading is 800 mm. The dust is collected in the sintering dust bin. After ignition and sintering, dust spreading is carried out 2 meters away from the sintering igniter, and the spreading thickness is 20 mm. At about 25 meters away from the ignition point, all the fine dust on the surface layer of the sintering is sucked into the sintering material layer. The sintering indexes are as shown in Table 3 below.

[0039] Table 1 Dust composition and particle size composition (mass fraction)

[0040]

[0041] It can be seen from the comparison of the sintering indexes before and after without dust spreading on the surface of the sintering material layer. During the sintering suction process, due to the addition of dust, the vertical sintering speed is reduced. However, due to the addition of carbon, the heat in the sintering process of the upper layer of the sintering material is increased, promoting the agglomeration of the upper layer of the sintering material, increasing the sintering drum index by 1.9% and the finished product rate by 1%.

[0042] Example 2

[0043] A sintering machine includes a sintering pallet 1, a feeder 5, an igniter 2 arranged in sequence along the running direction of the sintering pallet, and a plurality of wind boxes 8 located below the sintering pallet. It also includes a dust bin 3 and a dust spreader 4. The dust bin 3 is located downstream of the igniter 2. The dust bin 3 and the dust spreader 4 are cuboids. The dust bin 3 is placed vertically, and the dust spreader 4 is placed obliquely. The angle between the dust spreader 4 and the vertical direction is 45°. The bottom of the dust bin 3 is connected to the top of the dust spreader 4. The distance between the discharge port 13 of the dust spreader 4 and the bottom of the sintering pallet 1 is 1100 mm. The horizontal distance between the discharge port 13 of the dust spreader 4 and the igniter 2 is greater than 2 m. The length of the discharge port 13 of the dust spreader 4 is equal to the width of the sintering pallet 1, and the width of the discharge port 13 of the dust spreader 4 is 5 cm.

[0044] Using the base material bin 14, sintered ore is laid as the base material in the sintering pallet 1. The sintering raw materials are evenly laid above the base material by the feeder 5. The igniter 2 ignites. Dust with a carbon content greater than 20% and a particle size of 200 mesh for more than 50% is collected in the dust bin 3. The dust spreader 4 conducts dust distribution in the width direction of the sintering pallet 1, and the dust is evenly sprayed on the surface of the sintering raw materials. The wind boxes 8 suck the dust into the sintering material layer under the action of the induced draft fan 10. According to the position of the sintering end point, the cloth thickness of the dust is adjusted so that the dust is sucked into the material layer at 1 / 3 - 1 / 2 of the sintering section. After the dust and the material layer are sintered, sintered ore is formed. The sintered ore enters the crusher 9 at the tail of the sintering pallet 1, is crushed, and then enters the ring cooler 7 for cooling. The screen 12 screens the crushed sintered ore and then enters the blast furnace for the next process.

[0045] The dust used is blast furnace bag dust, and its composition and particle size composition are as shown in Table 4 below. Now, 480 m 2 The length of the pallet of the sintering machine is 96 meters. During normal sintering, the position of the sintering end point fluctuates little, and the length of the sintering section is about 80 meters. The cloth thickness of the base material is 60 mm, and the cloth thickness of the sintering raw materials is 800 mm. The dust is collected in the sintering dust bin. After ignition and sintering, dust distribution is carried out 2.5 meters away from the sintering igniter, and the cloth thickness is 30 mm. At about 35 meters away from the ignition, all the fine dust on the surface of the sintering layer is sucked into the sintering material layer. The sintering indexes are as shown in Table 6 below.

[0046] Table 2 Dust Composition and Particle Size Composition (Mass Fraction)

[0047]

[0048] It can be seen from the comparison of the sintering indexes before and after the dust is not distributed on the surface of the sintering material layer. During the sintering induced draft process, due to the addition of dust, the vertical sintering speed is reduced. However, due to the addition of carbon, the heat in the sintering process of the upper layer of the material is increased, promoting the agglomeration of the upper layer of the sintering material, increasing the sintering drum index by 2% and the yield by 1.5%.

[0049] Example 3

[0050] A sintering machine includes a sintering trolley 1, a feeder 5, an igniter 2 arranged in sequence along the running direction of the sintering trolley, several wind boxes 8 located below the sintering trolley, and also includes a dust bin 3 and a dust spreader 4. The dust bin 3 is located downstream of the igniter 2. The dust bin 3 and the dust spreader 4 are cuboids. The dust bin 3 is placed vertically, and the dust spreader 4 is placed obliquely. The included angle between the dust spreader 4 and the vertical direction is 45°. The bottom of the dust bin 3 is connected to the top of the dust spreader 4. The distance between the discharge port 13 of the dust spreader 4 and the bottom of the sintering trolley 1 is 900 mm. The horizontal distance between the discharge port 13 of the dust spreader 4 and the igniter 2 is greater than 2 m. The length of the discharge port 13 of the dust spreader 4 is equal to the width of the sintering trolley 1, and the width of the discharge port 13 of the dust spreader 4 is 5 cm.

[0051] Using the base material bin 14, sintered ore is laid as the base material in the sintering trolley 1. The sintering raw materials are evenly laid above the base material by the feeder 5. The igniter 2 ignites. Dust with a carbon content greater than 20% and a particle size of 200 mesh for more than 50% is collected in the dust bin 3. The dust spreader 4 conducts dust distribution in the width direction of the sintering trolley 1, and the dust is evenly sprayed on the surface of the sintering raw materials. The wind box 8 sucks the dust into the sintering material layer under the action of the exhaust fan 10. According to the position of the sintering end point, the cloth thickness of the dust is adjusted so that the dust is sucked into the material layer at 1 / 3 - 1 / 2 of the sintering section. After the dust and the material layer are sintered, sintered ore is formed. The sintered ore enters the crusher 9 at the tail of the sintering trolley 1 for crushing and then enters the annular cooler 7 for cooling. The screen 12 screens the crushed sintered ore and then enters the blast furnace for the next process.

[0052] The dust used is blast furnace bag dust and coking environmental dust with a mass ratio of 1:1. Its composition and particle size composition are as shown in Table 1 below. Now, 480 m 2 The normal production indexes of the surface of the sintering machine material layer without dust cloth are shown in Table 2. The length of the trolley is 96 meters. During normal sintering, the position of the sintering end point fluctuates little, and the length of the sintering section is about 80 meters. The cloth thickness of the base material is 60 mm, and the cloth thickness of the sintering raw materials is 800 mm. The dust is collected in the sintering dust bin. After ignition and sintering, dust cloth is carried out 2 meters away from the sintering igniter, and the cloth thickness is 20 mm. At about 25 meters away from the ignition, all the fine dust on the sintering surface layer is sucked into the sintering material layer.

[0053] Table 3 Dust Composition and Particle Size Composition (Mass Fraction)

[0054]

[0055] It can be seen from the comparison of sintering indexes before and after without dust distribution on the surface of the sintering material layer that during the sintering suction process, due to the addition of dust, the vertical sintering speed decreases. However, due to the addition of carbon, the heat in the sintering process of the upper layer of the sintering material increases, promoting the agglomeration of the upper layer of the sintering material, increasing the sintering drum index by 2.3% and the finished product rate by 1.2%.

[0056] Comparative Example 1

[0057] Using the sintering machine described in Example 3, without dust distribution, 480m 2 The trolley length of the sintering machine is 96 meters. During normal sintering, the position of the sintering end point fluctuates little, and the length of the sintering section is about 80 meters. The thickness of the sintering raw material distribution is 60mm.

[0058] Comparative Example 2

[0059] Using the sintering machine described in Example 3, the dust used is blast furnace bag dust, and its composition and particle size distribution are as shown in Table 4 below. Now, 480m 2 The trolley length of the sintering machine is 96 meters. During normal sintering, the position of the sintering end point fluctuates little, and the length of the sintering section is about 80 meters. The thickness of the bottom material distribution is 60mm, and the thickness of the sintering raw material distribution is 800mm. The dust is collected in the sintering dust bin. After ignition sintering, dust distribution is carried out 2 meters away from the sintering igniter, with a distribution thickness of 20mm. At about 25 meters away from the ignition point, all the fine dust on the sintering surface layer is sucked into the sintering material layer.

[0060] Table 4 Dust composition and particle size distribution (mass fraction)

[0061]

[0062] Comparative Example 3

[0063] Using the sintering machine described in Example 3, the dust used is coking environmental ash, and its composition and particle size distribution are as shown in Table 5 below. Now, 480m 2 The trolley length of the sintering machine is 96 meters. During normal sintering, the position of the sintering end point fluctuates little, and the length of the sintering section is about 80 meters. The thickness of the bottom material distribution is 60mm, and the thickness of the sintering raw material distribution is 800mm. The dust is collected in the sintering dust bin. After ignition sintering, dust distribution is carried out 2 meters away from the sintering igniter, with a distribution thickness of 20mm. At about 25 meters away from the ignition point, all the fine dust on the sintering surface layer is sucked into the sintering material layer.

[0064] Table 5 Dust composition and particle size distribution (mass fraction)

[0065]

[0066] The sintering production indexes of Examples 1 - 3 and Comparative Examples 1 - 3 are shown in Table 6.

[0067] Table 6 Sintering Production Indexes

[0068]

[0069]

[0070] As can be seen from Table 6, during the sintering process, the addition of dust reduces the vertical sintering speed. However, due to the addition of carbon, the heat in the sintering process of the upper layer of the sintering material increases, promoting the agglomeration of the upper layer of the sintering material and improving both the sintering drum index and the finished product rate.

[0071] In Example 1 and Example 2 using blast furnace bag dust, the finished product rate increased by 1.5% and 1.8% respectively compared to Comparative Example 1 without using dust. In Example 3 using blast furnace bag dust and coking environmental dust, the finished product rate increased by 2.4% compared to Comparative Example 1. In Comparative Example 2 using blast furnace bag dust, the finished product rate increased by 1.1% compared to Comparative Example 1. In Comparative Example 3 using coking environmental dust, the finished product rate increased by 1% compared to Comparative Example 1. Thus, it can be seen that laying dust on the surface of the sintering material layer in the present invention can improve the finished product rate and the sintering drum index and reduce the vertical sintering speed.

[0072] The present invention utilizes the characteristics of the sintering process, adds a dust bin and a dust spreader, and distributes fine dust with a high carbon content on the surface of the sintering material layer after sintering ignition, solving the problem of fluctuations in sintering indexes caused by unknown carbon in this part of the dust in the past. At the same time, due to the sintering suction effect, the dust is drawn downward, blocking most of the voids in the material layer and making the cross-section of the material layer sinter more uniformly. At the same time, the dust enters the sintering layer and is ignited and burned, providing heat and promoting the formation of the sintering liquid phase. On the other hand, the dust distributed on the surface of the sintering material layer plays a surface heat preservation role and is also beneficial to improving the sintering finished product rate.

[0073] The above are only the preferred embodiments of the present application and are not used to limit the present application. For those skilled in the art, various changes and modifications can be made to the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included within the protection scope of the present application.

Claims

1. A sintering machine, characterized in that, It includes a sintering trolley, a feeder, an igniter arranged successively along the running direction of the sintering trolley, an air box located below the sintering trolley, and also includes a dust bin and a dust spreader. The dust bin is located downstream of the igniter. The bottom of the dust bin is connected to the top of the dust spreader. The bottom discharge port of the dust spreader is located above the sintering trolley. The carbon content of the dust is greater than 20%, and more than 50% of the dust particle size is 200 mesh.

2. The sintering machine according to claim 1, characterized in that, The dust bin is placed vertically, and the dust spreader is placed obliquely.

3. The sintering machine according to claim 2, wherein, The included angle between the dust spreader and the vertical direction is 30° - 60°.

4. The sintering machine according to claim 1, characterized in that, The distance between the discharge port of the dust spreader and the bottom of the sintering trolley is 900 - 1100 mm, and the horizontal distance between the discharge port of the dust spreader and the igniter is greater than 2 m. The length of the discharge port of the dust spreader is equal to the width of the sintering trolley, and the width of the discharge port of the dust spreader is 3 - 8 cm.

5. The sintering machine according to claim 1, wherein, It also includes a crusher located at the tail of the sintering trolley. There is a ring cooler behind the crusher. There is a screen below the ring cooler. The bottom of the air box is connected to a dust collector through a pipeline. The dust collector is connected to a suction fan through a pipeline. There is a base material bin upstream of the feeder.

6. The method for improving the sintering finished product rate by using the sintering machine according to any one of claims 1-5, characterized in that, It includes the following steps: The base material bin lays the base material in the sintering trolley. The feeder lays the sintering raw materials above the base material. The sintering trolley runs. The igniter ignites. The dust is collected in the dust bin. The dust spreader conducts dust spreading in the width direction of the sintering trolley. The air box sucks air to the lower part of the sintering trolley and sucks the dust into the sintering raw materials. The carbon content of the dust is greater than 20%, and more than 50% of the dust particle size is 200 mesh.

7. The method for improving the sintering finished product rate according to claim 6, characterized in that, The cloth thickness of the dust is 10 - 30 mm, and the dust is sucked into the sintering raw materials at 1 / 3 - 1 / 2 of the sintering section.

8. The method for improving the sintered finished product rate according to claim 6, characterized in that, The dust is one or more of blast furnace bag dust, coking environmental dust, etc.

9. The method for improving the sintering finished product rate according to claim 6, characterized in that, The cloth thickness of the base material is 50 - 60 mm, and the cloth thickness of the sintering raw materials is 800 - 1000 mm.

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