SU985093A1 - Method and apparatus for charging burden onto sintering machine - Google Patents

Description

(5) METHOD FOR LOADING A DRAWING ON ANGLOMERATION MACHINE AND A DEVICE FOR ITS IMPLEMENTATION The invention relates to ferrous metallurgy and can be used in the sintering of iron ores and concentrates. Methods are known for the agglomeration of iron ores and concentrates, including loading, blending and sintering of the charge on an sintering machine. Loading of the charge on the grate of the sintering machine is carried out in such a way that its particle size distribution across the width of the bulk layer, with the exception of parts located at the sides of the grate, is unchanged. The disadvantage of these methods is that it is not possible to increase the gas permeability of the central part by the width of the bulk layer. Along with the loading of larger fractions jJJxts to the sides of the grate, this causes the onboard air swabs, leads to a decrease in the productivity of the sintering machine and the presence of underheat in the sinter, increases the mechanical loss of raw materials in the quail and enhances the blocking of the grate. Conducting a process with an extended high temperature zone leads to an increase in the residence time of the sintering machine's grates at temperatures above 1000 ° C, accelerating their burning, and an increase in the temperature of the hot sinter. Therefore, the process of its cooling, for example, on linear coolers, is characterized by their low productivity and large thermal damage with the formation of a high content of fines less than mm in it and an increase in the loss of raw materials. The closest to the proposed technical essence and the achieved result is a method of sintering iron ores and concentrates, including loading with the formation in the layer of vertical layers of materials with increased gas permeability, ignition and sintering of the charge on the sintering machine. Relatively large components of the charge are used as materials with increased gas permeability: return or a mixture of lime with solid fuel 2 3. Increasing gas permeability, especially in the center of the batch, contributes to the intensification of the process: increase in productivity of the sintering machine and, due to the increase in height layer, reducing the consumption of solid fuel in the charge and the content of fines less than mm in a suitable sinter. A device for loading the charge on an sintering machine is known, which includes a hopper with a window for dispensing material, a drum and an inclined sheet. A feature of this device is that when the drum is rotated out of the bunker, the charge through the window of dispensing, scattering along the inclined sheet, segregates along the height of the sintering machine formed on the belt. In this case, the small parts of the charge are placed in the upper horizons of the f3 bulk layer. Technological drawbacks of the method are due to the fact that the use of return for interlayers leads to the formation of volumes in the sintered layer, used for the production of ag-. lomerata. The return in the process practically does not bake, in connection with which it is a source of an increase in the fines content of less than mm in a suitable ai-meromate and the removal of charge materials from the layer. The use of a return with a particle size of more than 5.0 mm causes a sharp increase in the gas permeability of the interlayers and, as a consequence, insufficient batching of the lower layers of the bulk layer, a decrease in the yield of suitable agglomerate. The need for a large number of return to the charge and for interlayers complicates the operation of crushers and sinter screens. The use of a mixture of limestone and solid fuel for interlayers additionally requires the adoption of measures to prevent significant dusting and loss of raw materials during the transportation of oaglomerate, which is especially enhanced when decomposing undissolved lime. In addition, in this method, the average mass temperature of the agglomerate is not reached, since conditions for its mastic cooling are not created on the sintering machine. The cooling of the agglomerate on the linear cooler still occurs with a significant increase in the content of fines less than 5.0 mm and the loss of raw materials. The presence of these drawbacks does not allow the use of this method in industry and does not provide the maximum possible improvement in the performance of agloprocesses. The drawback of the device is that with its help it is not possible to form vertical interlayers with large fractions of the sinter blend in the bulk layer. The purpose of the invention is to improve the performance of the sintering machine, improve the quality of sinter and save solid fuel. The goal is achieved by the fact that according to the method of sintering iron ores and concentrates, including loading with the formation in the layer of vertical layers of materials with increased gas permeability, ignition, and sintering of the charge on the sintering machine, for vertical layers, during loading, separate the mixture with the content of the class less than 1.6 mm is equal to 6 - (C%. In addition, vertical interlayers form 3/3 of the height of the bulk layer of the charge. A device for loading the charge on the sintering machine, including a hopper with a window material, drum and inclined sheet, are provided with horizontal plates evenly spaced above the drum with a width of 0.01-0.08 of the drum width, height O, A-1.2 of the dispensing window at a distance from it during the rotation of the drum 0, , 8 of its diameter. In addition, the device is equipped with plates installed below the edge of an inclined sheet at a distance of l / lO-l / its length at an angle of 60-135 to it with an offset from the plane of the sheet to 1 / 10-1 / 3 of the window height issuing. FIG. 1-3 shows the device for loading the charge on the sintering machine, general view. The device comprises a hopper 1 with a window 2 for dispensing the material, a drum 3, an inclined sheet k, along which the charge is poured, onto the grid 5 of the sintering machine. FIG. 1, the plates 6 are shown when they are installed above the drum 3 at a distance from the dispensing window 2 in the course of the rotation of the drum 3, equal to 0.6 of its diameter 598. The width of the plates is equal to 0.05 of the width of the drum 3, and the height 1, 2 of the height of the window 2 of the issue. In FIG. 3, four plates 6 are shown when they are installed in the charge layer formed on the tape 5 below the edge of the inclined sheet at a distance of 1/20 of a length under the yoke 135 to it with an offset from the plane of the sheet equal to 1/5 of the height of the window 2 issuing. J The mixture of increased gas permeability for vertical interlayers, t, that is, its class content is less than 1.6 mm, and the height of interlayers in the bulk layer, as well as the size and location of the plates 6 of the device for loading charge 7 to the sintering machine are selected from the following conditions: sinter machine; solid fuel savings; quality improvement. aglo merata; lower average mass temperature of sinter; ensuring the operability of the device for carrying out the method; reduction of mechanical losses of raw materials; reduction of the grate dwell time at high temperatures. As can be seen from the table. 1, these conditions are fulfilled when creating vertical interlayers of increased gas permeability in the sintered layer of the charge with a grade less than 1.6 mm in it equal to 6-14, i.e., 12.720, 7 less than in the total weight of the charge. Increasing the grade of less than 1.6 mm 8 of the charge of layers 8 more than 1 does not allow to significantly increase the gas permeability of the layer and to ensure the improvement of the performance of the agglomeration process in comparison with the known technologies. In order to ensure high-quality sintering of the charge of the interlayers 8, the content in them of small classes up to 1.6 mm, having a developed contact surface and an increased content of solid fuel, must be at least 6%. 8 Otherwise, a poorly sintered agglomerate is obtained from the charge of interlayers 8. An excessive increase in their gas permeability also causes deterioration of the sintering conditions and the rest of the mass of the charge layer. A device for implementing the method {FIG. 1 and 2) is performed with evenly spaced widths above the drum 3 110 plates 6 width jj 0.01-0.08 of the width of the drum 3, height 0.1-1.2 of the height of the dispensing window 2 at a distance from it during the rotation of the drum 3 0,, 8 of its diameter. 3 The regulation of the content of fine fractions in the charge of the interlayers 8 is carried out by changing the width and height of the plates 6. A decrease in the class content of less than 1.6 mm to k% in the charge of the interlayers 8 is observed only along the width of the plates 6 of at least 0 mm, and above 6% - to 200 mm. In addition, the width of the plates 6 more than 200 mm can lead to the formation of furrows under the bulk layer, which makes it difficult to maintain the charge level above the lower edge of the inclined sheet k per mm (to create segregation along the height of the charge) according to a typical technological instruction. Sintering machines are used in industry, mainly having a width of the working surface, and therefore a drum, 2.5 and A. m. The width of the plates 6 ,, is 40-200 mm, for an sinter machine with a working surface width of 2.5 m corresponds to 0, 01b-0.08 of the width of the drum 3, and for ag machines with the width of the working surface m 0, 01-0.05 of the width of the drum 3- In general: for 1 standard agglomachines, the width of the plates 6 should be 0.01-0, 08 drum width 3- In practice, sintering machines with a working width of 2 m are rarely but still used. In the claimed limits, the upper limit of widths plates 6 for them is 160 mm. As can be seen from the table. 1, with this width of the plates 6, it is possible to obtain results that are only slightly inferior to the results obtained with a plate width of 200 mm. The height of the plates 6 determines which part of the height of the flow of the charge of the plates 6 coming to them through the dispensing window 2 from the hopper 1 of the plate 6 is cut off to form a vertical layer in the bulk layer. 8. The height of the flow entering the plates 6 depends on the height of the output window 2. A decrease in the height of the plate 6 is less than 0, the height of the output window 2 causes the more than necessary amount of charge to be poured through the plates 6, and lower the maintenance of small classes in layers 8 is not possible. In order to reduce the content of small classes in bulk by 8 to 6%, it is necessary to almost completely eliminate pouring of the charge through the plates 6. Since, when the charge of the charge on the plates 6, there is some increase in the height of the moving material flow, the plates are about to completely eliminate the charge, It is necessary to perform slightly higher than the height of window 2 of the dispensing, namely, 1.2 times. Increasing the height of the plates 6 to more than 1.2 the height of the delivery window 2 leads to the formation of non-working parts and does not affect the performance of the agglomeration process. These parts of the plates 6 are not technologically advanced, but can be used for fastening, i.e., in some cases are supports. The uniform arrangement of the plates 6 above the drum 3 ensures a uniform increase in the gas permeability of the central part across the width of the blended blend In the course of the tests carried out, it was determined that the installation of plates 6 with a displacement relative to a uniform arrangement of 0.005 width of the drum 3 leads, for example, to a decrease in the performance of the sintering plant on O, to an increase in the consumption of TV rdogo fuel by O, 1 kg / t and sinter fines content of less than 5,0mm in the tympanic agglomerate sample at 0.02% (abs.). Improved performance aglomashiny observed during installation of the first plate 6 to the center of the bar-30

Ban 3. An increase in the gas permeability of the central part of the bulk layer, which occurs in this case, is particularly effective in eliminating the shortage of vaglomer. An increase in the number of 35 wa plates of 6 more than ten does not lead to an additional improvement in the performance of the agloprocessor.

In order to ensure the operability of the device, the plate 6 must be set at a distance of at least 0.3 of its diameter from the delivery window 2 in the course of rotation of the typical drum 3. Otherwise, the conditions for the release of the charge 7 from the bunker 1 are worsened, it is possible to charge back wedge-shaped protrusions from the charge, which are formed above the plates 6, of the material and the filling of the discharge window 2. At a distance of more than 0.8 of the diameter of the drum 3, the charge 7 begins to flow 50 onto an inclined sheet, the face of plate 6 ,. Their effect on the redistribution of the charge across the width of the bulk layer is eliminated. Placing the plates 6 on an inclined sheet is impractical, jj since in this case the build-up of charge on it increases, which is one of the reasons for the deterioration of the agglomeration indicators. 98

ek 8 Leads to heat deficiency in the upper layers of the layer and does not allow improving the performance of the agloprocess. Reducing the height of the layers 8 to less than 3 / the height of the layer leads to the creation of excess heat in the lower horizons and, as with conventional technology, adversely affects the operation of the sintering machine.

The device for carrying out the method can be performed with the plates 6 installed below the edge of the inclined sheet k at a distance of 1/10 - 1/7 of its length at an angle of 60-135 ° to it with displacement relative to the plane of the sheet. k, equal to 1 / 10-1 / 3 the height of the window 2 of the issue.

The height adjustment of the interlayers 8 is carried out by changing the distance of the plates 6 from the lower edge of the inclined sheet k. Since the height of the layer of sintered charge usually varies between 250-300 mm, and sometimes 200-AOO mm, it is generally necessary to set the depths of the lower edge of the sheet k to at least 5 35 mm, and for interlayers 8 with a height of 3 / layer height - 100 mm. At 3-8 table. 2 shows the results of experiments on RO sintering of charges with the formation of vertical interlayers 8 at a given height of the bulk layer due to the installation of four plates 6 with a width of 100 m below the edge of the inclined sheet k. From tab. 2, it follows that the formation of vertical interlayers 8 at the height of the bulk charge layer is optimal. This is due to the fact that in the upper layers of the layer during sintering, as a rule, there is a shortage of heat, while in the subsequent layers there is an excess of it. When the interlayers 8 are formed over the entire height of the bulk layer, the heat deficit, due to the decrease in the content of small classes, and hence solid fuel in the upper horizons, can be somewhat exacerbated. A positive effect, besides improving the gas permeability of the layer, is achieved by eliminating the excess heat in the lower horizons of the interlayers 8. In order to compensate for the lack of heat in the upper horizons of the interlayers 8, it is necessary to cover them with a charge with an increased content of small classes. The desired effect is achieved even when the height of the layers 8 is not more than 5/6 of the height of the layer. A further increase in the height of the progressed aglo-machines, the length of the inclined sheet k is 700-100 mm. With a length of 700 mm of an inclined sheet t, the limits of the distance mm from the plates 6 correspond to 1 / 20-1 / 7 of the sheet length, and with its length mm 1 / AO-1 / 1A sheet length i. In general, plates should be installed from an inclined sheet at a distance of 1/1/7 of its length. In order to feed the charge cut off by the plates 6 onto the grate 5 of the sintering machine over the bulk layer, which is necessary to create segregation of the charge over the height of the layer, and transverse with the formation of vertical layers 8, the plates 6 should be set at an angle of no more than 135 to the inclined sheet. If this area is not observed, the charge supplied to the plates 6 is poured over them directly onto the grate 5 and the bulk layer formed is not formed. As a result, a charge with a higher content of fine fractions can enter the lower layers of the layer 25 than with conventional technology. This dramatically worsens the performance of the agloprocess. An angle of less than 60 ° leads to the fact that, due to a decrease in the volume bounded by the plates to it by the layer being formed, the height of the ledge from small fractions of the charge increases sharply. This ledge begins to form 35, already above the edge of the inclined sheet A, the build-up of charge on it increases. It is necessary to constantly clean the inclined sheet k, which is impossible under industrial conditions. In addition, in addition, the bottles and lumps of more than 200 mm falling in this case are wedged between the plates 6 and the bulk layer, disrupting the operation of the device, as for. Clinical treatment of butts and lumps of identity-45 but installing plates 6 more than 200 mm, or descend from partitions to the upper rather than to the lower horizons of the layer, where there are no conditions for their sintering due to the shortage of heat. The displacement of the plates 6 is relative, but the plane of the sheet determines the amount of batch that spills during the formation of the layer under the plates 6 and is intended to control the content jj of the fraction less than 1.6 mm in the vertical interlayers 8. The selection of this displacement relative to the height of the dispensing window 2 is due to That this cell height determines the thickness of the charge flow that is flowing in the formed layer. When the plates 6 are displaced more than 1/3 of the height of the window 2 of the discharge relative to the plane of the sheet, the plate 6 does not provide a predetermined reduction of fine fractions (to It) in the vertical layers 8. The plates 6 completely overlap. The charge flow is transferred at their displacement relative to the plane of the sheet, equal to 1/10 of the height of window 2, and ensure the minimum content of fines in the vertical layers 8. Further, a decrease in this displacement causes the plates 6 to begin enter the formed layer, breaking its structure. A part of the material is captured and accumulated under the plates 6. The hollows below them, necessary for the transverse segregation of the charge, disappear. The formation of the vertical layers 8 stops. The essence of the method is as follows. The vertical layers 8 do not create from the large components of the sintering mixture, but from itself, but only containing a reduced amount of a class less than 1.6 mm (), while in the total weight of the mixture the content of this class is 20-30. Besides the fact that it allows using the sintering technology of the charge with vertical layers 8 of increased gas permeability in the industry, improving it makes it possible to further improve the performance of the agglomerate: to increase the productivity of the sinter machine, to reduce the consumption of solid fuel into the charge, and to improve the quality of the sinter. This is due to the fact that, with a selected grade of less than 1.6 mm, the mixture of vertical interlayers 8 has an increased gas permeability and is sufficiently sintered, which results in an increase in the yield of agglomerate, as well as in a reduction in raw material losses in the redistribution. The lack of heat in the vertical layers 8 is eliminated when laying on them small classes of the charge containing an increased amount of solid fuel. In this case, a vertical distribution of B creates a more rational distribution of solid fuel along the height of the bulk layer, and m, in the rest of its mass, in which the distribution of solid fuel across the height of the bulk layer is carried out, as with the usual loading of the charge 7 on the grid 5 of the sintering machine . At the same time, the interlayers 8 allow not only to increase the gas permeability of the entire layer and, accordingly, to improve the performance of the process, but also are parts of the layer that contribute the least amount of fines less than 5.0 mm to a suitable agglomerate. The narrowing of the high temperature zone, the elimination of excess heat in the lower horizons of a significant part of the layer (in the vertical layers 8), and the absence of underheating affect the working conditions of the grate. Sleep: the increase in the residence time of grates at temperatures above allows increasing their durability, i.e., reducing consumption. It is also characteristic that during sintering of the charge by this method, two consecutive processes are combined on the sintering machine: sintering of the charge and cooling of the agglomerate. The agglomerate of the interlayers 8 after the sintering of the total mass of the charge is completed is sufficiently cooled. The maximum temperature in it is BOO-HEO C, while in the rest of the mass, as usual, it reaches 1300 ° C. This can be estimated as a partial cooling of the agglomerate on a sintering machine, but without special allocation for this working area. Thus, the average mass temperature of the agglomerate decreases, which has a positive effect on the crushing and grit and cooling characteristics of the agglomerate, and also allows an increase in equipment durability. The vertical interlayers 8 are like a rigid framework of the entire bulk layer of the charge. A thin layer of sinter formed in the uppermost horizons takes on itself a shock of the gas stream entering the layer. Layers 8 rigidly back spec the upper horizons. This reduces the shrinkage of the entire sintered layer and provides increased permeability to the parts of the layer 7, located between the layers 8, throughout the whole process. In addition, the simplicity of the apparatus for carrying out the method minimizes the complexity of the technology. The device for loading the charge on the sintering machine operates as follows. Charge 7, unloaded when the drum 3 is rotated. Through the output window 2 of bunker 3, ker 1, flows along the inclined sheet k in separate streams (Fig. 1 and 2) between the plates 6. While maintaining the charge level above the lower edge of the inclined sheet C, not less than by 20 mm, according to the standard technological instruction, wedge-shaped protrusions are formed on it in the places where the charge 7 falls from the drum 3. According to their forming segregation of charge 7 occurs not only in height, but also in width of the formed layer. Very large granules, including the bottles, do not change their linear motion and, together with the uncombed charge, the angle of repose of which is significant, after segregation in height, are loaded with a layer on the grid 5 into places located between the plates 6. A mixture of intermediate classes, having an angle of repose smaller than its non-clawed part, with a minor content of the latter, the ho lateral forming wedge-shaped projections changes the direction of its movement and is loaded onto the grating 5 in places located x under. plates 6. Over the entire width of the bulk layer, vertical F | 5 layers 8 of increased gas permeability appear. For laying small classes of the charge 7 on the vertical windows of the 8 (Fig. 3) plates 6 are installed under the loading sheet k in a pouring 1LYHT flow. The wedge-shaped protrusions for the transverse segregation of charge 7 in this case mainly form directly on the slope of the charge already formed on the grate 5. The small classes accumulate on the plates 6, and then fall down into vertical layers. 8, cover them. The formation in the layer of vertical interlayers 8 at a certain height of the bulk layer is achieved. The use of the proposed invention in comparison with the known ones will provide (at a height of the sintered batch of the mixture of 300 mm) an increase in the productivity of the sintering plant by 2.1-7.9%; reducing the fines content of less than 5.0 mm in the agglomerate by 0.22-1, (abs.); reduction of solid fuel consumption to the charge by 0 kg / ton of sinter; reduction of charge losses by 0,, 30 (abs.); lowering the average temperature of the hot sinter to 10120 C. At the same time, the equipment durability will increase and the grate consumption will decrease.

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Claims (3)

LA 17 Invention 1. The method of loading the charge on the sintering machine includes, in particular, the formation in the layer of vertical layers of materials with a higher gas permeability, characterized in that, in order to increase the productivity of the sintering machine, improve the quality of sinter and save solid fuel,. when loading the charge, vertical layers separate the charge with a class content of less than 1.6 mm, equal to 6-14 .. 2. The method according to claim 1, is also distinguished by the fact that the vertical layers form on the heights of the bulk layer . 3. A device for loading the charge on the sintering machine, containing a hopper with a window for dispensing material, a drum and a sloped sheet, which is provided with horizontal plates that are evenly 98 18 widthwise above the drum at a distance from the dispensing window in the direction of rotation of the drum is 0.3-0.8 of its diameter, the width of the plates being 0.01-0.08 of the width of the drum and the length 0.4-1.2 of the height of the dispensing window. k. The device according to claim. 3 | This is due to the fact that the plates are installed below the edge of an inclined sheet at a distance of 1 / 0-1 / 7 of its length at an angle to it 60-135, offset from the plane of the sheet equal to 1 / 10-1 / 3 of height window issue. Sources of information taken into account in the examination 1. S. Bazilevich, V. Vogman. Agglomeration. Moscow, Metallurgists, 1967 p. ten. 2. USSR author's certificate number 20659, cl. From 21 to 1/20, 19b5. 3.V.Korrtic Fundamentals of the theory and technology of preparation of raw materials for blast furnace smelting. M., Metallurgists, 1978, p. 167.