Claims:We Claim:
1. A process for sintering iron ore including step of systematic generation of raw material mix for required subsequent nodulization and sintering comprising: selectively and sequentially involving raw materials fluxes including dolomite, limestone with iron ore for mixing comprises sequentially piling for mixing the said dolomite, iron ore and limestone following a sandwich layering technique with said iron ore sandwiched between either of the flux selectively said dolomite and limestone such that during mixing finer particles of said fluxes form a coating over the iron ore whereby the thus coated iron ore provide desired adherence for effective granulometry of any variety of iron ore during nodulizing for effective sintering.
2. The process as claimed in claims 1 including :
i) step of mixing of raw materials involving said systemic generation of raw materials fluxes including dolomite, limestone with iron ore for mixing involving sandwiched pile of iron ore blend comprising: a) providing a sandwiched pile of iron ore blend comprising of layering of iron ore , lime stone and dolomite including any variety of iron ore content including selected from porous and/or soft iron ore and/or hard and/or dense iron ore ;
b) carrying out sequential mixing of said flux and iron ore from said sandwiched pile of iron ore blend homogenously to coat the iron ore with limestone and form a green mix ;
ii) involving the thus obtained green mix to granulation to form granules ; and
iii) finally sintering the granules in a sinter bed.
3. The process as claimed in anyone of claims 1 or 2 comprising:
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preparing a pile by layering limestone, iron ore dolomite and coke; wherein the iron ore is sandwiched between the limestone and dolomite; mixing the pile homogeneously to coat the iron ore with limestone and form a green mix; mixing the green mix in the mixing drum; adding the green mix, coke, calcined limes, return fines and water in the granulating drum; subjecting the green mix, coke, calcined limes, return fines and water to granulation to form granules; and sintering the granules on a sinter bed.
4.The process as claimed in anyone of claims 1 to 3 wherein the porous and/or soft iron ore is pisoliteore, goethiteore, limoniteore, sideriteore or a combination thereof.
5. The process as claimed in anyone of claims 1 to 4 wherein the porous and/or soft iron ore has the porosity value greater than 15%.
6. The process as claimed in anyone of claims 1 to 5 wherein optionally the iron ore is a blend of porous and/or soft iron ore and hard and/or dense iron ore.
7. The process of sintering iron ore as claimed in anyone of claims 1 to 6 comprising preparing said green mix in mixing drum at the speed of 20 rpm for 300 seconds; carrying out said granulation of green mix, coke, calcined limes, return fines and water in the granulating drum at the speed of 20 rpm for 480 seconds; and
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carrying out said sintering of granulated mix with sinter bed height maintained constant at 700 mm and hearth layer at 60 mm and ignition conditions of sinter bed comprising Suction air flow volume before ignition 2.0 m3/min Ignition holding time 60 sec Suction pressure after ignition -1200 mm H2O , Description:FIELD OF THE INVENTION
The present invention relates to a method to produce a sintered iron ore, involving sandwiched pile of iron ore blend including porous iron ore, to achieve required sinter quality for iron making in a blast furnace. More particularly, the present invention is directed to a method to produce sintered iron ore using porous iron ore by selectively piling in layers as iron ore sandwiched between limestone and dolomite layers, followed by thorough mixing, granulating and sintering to obtain iron ore sinter of required properties for use in blast furnace.
BACKGROUND OF THE INVENTION
In recent years, along with shortage of superior lump ore and deterioration of quality of ore fines, the raw material for sinter has deteriorated further than before, therefore, there have been strong demands for higher techniques that effectively improve the iron ore sinter quality. Several factors influence the sinter quality and sinter plant productivity. The nature and type of iron ore have a major impact on it. These different types of iron ore such as goethite, limonite, hematite and magnetite content impacts the agglomeration behavior differently. The physical nature of iron ore like porous or dense structure also influences the sinter quality and sinter plant productivity. The reduction in productivity is due to absorption of significant water by the porous iron ore which is added during the granulation process. This water is otherwise being available for inter-particle adhesion of raw materials and solid fuel. To facilitate the inter-particle adhesion during the granulation process requirement of water is increased. Increased water addition, during granulation also results in the formation of a "very wet" moisture condensation zone, which is ahead of the high temperature formation zone, during sintering. This could have an adverse influence on the permeability of the moisture condensation zone, the breakdown of granules in the moisture condensation zone and, consequently, the permeability of the sintering bed and the airflow distribution through the bed during sintering. In addition, a high water load in a sinter plant causes a lowering of exhaust gas temperatures, increased
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load on the fans, and, possibly, condensation in the wind legs and deterioration in electrostatic precipitator performance.
In various different reports, researchers have reported improvement in sinter plant productivity by blending the porous pisolite ore with the dense hematite ore.Japanese Patent No. 58-55221and Nisshin Steel Technical Report 1988, December, No. 59, 68-75entitled "Increase of Sinter Productivity by Pregranulation Process" discloses serpentine coating of the pisolite iron ore surface before granulation with other components to form a green mix. Further, Japanese patent No. 58-141341 discloses coating the surface of particles of pisolite ores with fine ores (greater than 80% of the fine ore particles less than 0.25 mm) prior to granulation with other components to form a green mix. The coated pisolite iron ore either with serpentine or fine ore is expected to alter the assimilation reaction of the ore particles during sintering and thereby improve sinter plant productivity.
Further, it was proposed to increase the water molecules during sintering so that the water requirement of the porous ore for granulation can be achieved with better granules. As pisolite iron ore is a goethitic type of ore already containing significant water, it may not be favorable to the sinter plant. In general, increased water content in the green mix causes a lowering of exhaust gas temperatures, increased fan load, and possibly, condensation in the wind legs and deterioration in electrostatic precipitator performance. Increased water addition may result in moisture condensation zone at the lower bed during sintering which could have an adverse effect on the bed-permeability and the airflow distribution through the bed during sintering.
Patent publication No. WO 1996001333-A1 discloses adding additives to alter the surface behavior of blend of iron ore and inhibit absorption of water into the porous ores. The additive may be any suitable material and includes, but is not limited to, starches, natural and synthetic gums, plant sugars and syrups, starch
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gums such as dextrin, by-products and wastes from sugar refineries such as molasses, animal and plant glues, gelatine, synthetic polymers such as polyelectrolytes, and substances such as polyethylene glycol, polyvinyl acetate, polyvinyl alcohol, and waxes. The patent discloses additives that have beneficial effect on granulation and also increase in productivity of the sinter plant. However, the Patent Publication No. WO 1996001333-A1is only based on the realisation that it is possible to incorporate soft/porous ores into iron ore blends without loss of sinter performance (measured by way of example by plant productivity) and sinter quality (measured by way of example by sinter strength) by inhibiting absorption of water into the iron ores. In addition, there are other factors also such as formation of slag during sintering that plays a very important role in increasing the sinter strength and productivity of the sintered iron ore. Slag formation increases the agglomeration during the sintering process. The additives disclosed in patent publication No. WO 1996001333-A1 fails to act as flux which in turn reduces the slag formation during sintering. Hence the sinter productivity and strength is low.
Applicant’s co-pending Patent Application No: 201721042832 entitled “A process for sintering of iron ore blend involving pre-processing of porous iron ore to improve sinter quality and plant productivity” worked on sintering of iron ore blend comprising highly porous iron ore involving pre-processing of such porous iron ore to block the pores and prevent water absorption during granulation in mixing and nodulizing drum in presence of water to improve sinter quality and plant productivity. In this method, calcined lime temporarily fills the pores and coat over the iron ore surface which helps in less water adsorption and early slag formation resulting in significant improvement in sinter quality and plant productivity.
As a result, a different water absorption additive is to be used that can be inhibiting absorption of water in the iron ore and in addition also acts as flux for agglomeration during sintering. Further, a detailed treatment step is required for
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coating the water absorption inhibitor additive evenly on the iron ore. The current disclosure provides a process to sinter iron ores of any kind to achieve better plant productivity and sinter quality than the conventional process. The present disclosure provides a new process of sintering of porous and/or soft iron ore overcome the disadvantages of low slag formation, lower sinter productivity.
OBJECTS OF THE INVENTION
The basic object of the present invention is directed to provide a process of sintering iron ore containing soft or porous ores to achieve higher sinter plant productivity and sinter quality.
A further object of the present invention is directed to provide a process of sintering iron ore containing soft or porous ores involving reduction in water requirements during granulation.
A still further object of the present invention is directed to provide process of sintering iron ore containing soft or porous ores wherein pre-processing of porous iron ore to avoid water absorption or involvement of any water absorption inhibitor can be eliminated.
A still further object of the present disclosure is directed to provide a process for sintering of iron ore blend for effective utilization of iron ores of different characteristics like limonite, goethite, and hematite, which can be dense or porous in nature and achieve higher sinter plant productivity and sinter quality.
A still further object of the present disclosure is directed to a process of sintering iron ore blend for increasing slag formation and higher sinter productivity.
SUMMARY OF THE INVENTION
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The basic aspect of the present invention is directed to a process for sintering iron ore including step of systematic generation of raw material mix for required subsequent nodulization and sintering comprising: selectively and sequentially involving raw materials fluxes including dolomite, limestone with iron ore for mixing comprises sequentially piling for mixing the said dolomite, iron ore and limestone following a sandwich layering technique with said iron ore sandwiched between either of the flux selectively said dolomite and limestone such that during mixing finer particles of said fluxes form a coating over the iron ore whereby the thus coated iron ore provide desired adherence for effective granulometry of any variety of iron ore during nodulizing for effective sintering. .
A further aspect of the present invention is directed to said process including (i) step of mixing of raw materials involving said systematic generation of raw materials fluxes including dolomite, limestone with iron ore for mixing involving sandwiched pile of iron ore blend comprising: a) providing a sandwiched pile of iron ore blend comprising of layering of iron ore , lime stone and dolomite including any variety of iron ore content including selected from porous and/or soft iron ore and/or hard and/or dense iron ore ;
b) carrying out sequential mixing of said flux and iron ore from said sandwiched pile of iron ore blend homogenously to coat the iron ore with limestone and form a green mix ;
(ii) involving the thus obtained green mix to granulation to form granules ; and
(iii) finally sintering the granules in a sinter bed.
A further aspect of the present invention is directed to said process of sintering iron ore comprising:
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preparing a pile by layering limestone, iron ore dolomite and coke; wherein the iron ore is sandwiched between the limestone and dolomite; mixing the pile homogeneously to coat the iron ore with limestone and form a green mix; mixing the green mix in the mixing drum; adding the green mix, coke, calcined limes, return fines and water in the granulating drum; subjecting the green mix, coke, calcined limes, return fines and water to granulation to form granules; and sintering the granules on a sinter bed.
A still further aspect of the present invention is directed to said process of sintering ore, wherein the porous and/or soft iron ore is pisolite ore, goethite ore, limonite ore, siderite ore or a combination thereof.
According to a further aspect of the present invention, said porous and/or soft iron ore has the porosity value greater than 15%.
A still further aspect of the present invention is directed to said process of sintering iron ore, wherein optionally the iron ore is a blend of porous and/or soft iron ore and hard and/or dense iron ore.
A further aspect of the present invention is directed to said process of sintering iron ore, comprising preparing said green mix in mixing drum at the speed of 20 rpm for 300 seconds; carrying out said granulation of green mix, coke, calcined limes, return fines and water in the granulating drum at the speed of 20 rpm for 480 seconds; and carrying out said sintering of granulated mix with sinter bed height maintained constant at 700 mm and hearth layer at 60 mm and ignition conditions of sinter bed comprising Suction air flow volume before ignition 2.0 m3/min
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The above and other objects and advantages of the present disclosure are described hereunder in greater details with reference to following accompanying non limiting illustrative drawings.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
FIG. 1: illustrates schematically the flow chart for conventional sintering process.
FIG. 2: illustrates the flow chart for a process for sintering porous and/or soft iron according to present invention.
FIG. 3 : illustrates sandwich layering of iron ore between limestone and dolomite.
Skilled artisans appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help to improve understanding of embodiments of the invention.
DETAILED DESCRIPTION OF THE INVENTION WITH REFERENCE TO THE ACCOMPANYING DRAWINGS
The present disclosure discloses a process of sintering iron ore. The steps include firstly, preparing a pile by layering limestone, iron ore dolomite and coke; wherein the iron ore is sandwiched between the limestone and dolomite. Secondly, mixing the pile homogeneously to coat the iron ore with limestone and form a green mix. Thirdly, mixing the green mix in the mixing drum. Fourthly, adding the green mix, coke, calcined limes, return fines and water in the granulating drum. Fifthly, subjecting the green mix, coke, calcined limes, return
Ignition holding time 60 sec Suction pressure after ignition -1200 mm H2O
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fines and water to granulation to form granules. Lastly, sintering the granules on a sinter bed.
Other features and aspects of the present advancement will be apparent from the following description and the accompanying drawings, wherein embodiments are illustrated by way of example and are not limited in the accompanying figures.
To illustrate the distinguishing features of the present invention over existing process of iron ore sintering, the steps of conventional sintering process, particularly the mixing and nodulizing steps are first explained below as illustrated through accompanying Figure 1:
In conventional sintering process, two methods are adopted for raw materials preparation (1) through bins or (2) through blend preparation. During Bin processing, raw materials are stored in bins which are added to mixer drum for homogeneous mixing followed by nodulization in mixer drum as shown in figure. During blend preparation processing, raw materials are piled one above the other and mixed using reclaimer. Once the raw materials are mixed thoroughly they are sent to mixer drum again and followed the similar process for sinter making as mentioned above. In this process the raw materials are piled in any fashion to fullfill the purpose of mixing during reclaimer process.
The present invention is now discussed in more detail referring to the drawings that accompany the present application. In the accompanying drawings, like and/or corresponding elements are referred to by like reference numbers.
Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or the like parts.
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The present invention relates to a process of sintering of iron ore. Preferably, the present advancement relates particularly to sintering an iron ore blend containing porous reactive ores, such as pisolite ore. According to the present invention, the process for sintering iron ore comprising: (i) preparing a pile by layering limestone, iron ore and dolomite; (ii) mixing the pile homogeneously to coat the iron ore with limestone and form a green mix; (iii) mixing the green mix in the mixing drum; (iv) adding the green mix, coke, calcined limes, return fines and water in the granulating drum; (v) subjecting the green mix, coke, calcined limes, return fines and water to granulation to form granules; (vi) sintering the granules on a sinter bed.
The present advancement is based on the realization that it is possible to incorporate soft and/or porous ores into iron ore without loss of sinter performance (measured by way of example by plant productivity) and sinter quality (measured by way of example by sinter strength) by inhibiting absorption of water into the soft or porous iron ores.
In this process, a systematic approach is adopted for stacking the raw materials, where the iron ore should be sandwiched between either of the flux (dolomite and limestone) so that the finer particles of these fluxes should form a coating over iron ore. The coated iron ore provides better adherence capability and thus improve granulometry of iron ore during nodulizing. The above said novel process is effective for any kind of iron ore. However, it has shown remarkable benefit to porous iron ore by filling the pores of iron ore and thus the subsequent benefits associated with it.
Accompanying FIG 2 illustrates the flow chart 100 for a process for sintering iron ore. Step 102 includes preparing a pile by layering limestone, iron ore and
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dolomite. The iron ore, limestone and dolomite are layered to form a pile. Preferably, the iron ore is sandwiched between the limestone and the dolomite. Accompanying Fig. 3 illustrates the layering of iron ore, limestone and dolomite. The iron ore 204 is sandwiched between the limestone 202 and dolomite 206. The iron is soft and/or porous iron ore or dense and/or hard iron ore. The porous and/or soft iron ore is pisolite ore, goethite ore, limonite ore, siderite ore or a combination thereof. The hard and/or dense iron ore is hematite ore. The porous and/or soft iron ore has the porosity value greater than 15%.Optionally, the iron ore is blend of porous and/or soft iron ore and hard and/or dense iron ore.
Alternatively, other raw materials are also piled to form layers. Other raw materials include return fines, coke breeze, calcined lime and other metallurgical wastes are also piled layer by layer. Preferably, bottom layer is made up of limestone, middle layer made up of iron ore and top layer made up of dolomite. The other raw materials are layered over the limestone or dolomite.
Step 104 includes mixing the pile homogeneously to coat the iron ore with limestone and form a green mix. These layer structure is mixed homogeneously to make a sandwiched product of iron ore covered with limestone. Alternatively, the limestone alters the properties, such as the surface properties, of the iron ores. For example, the limestone may have the effect of blocking or sealing the pores of the iron ores. The limestone also acts as a flux. The limestone promotes fluidity. The outcome is better agglomeration during the sintering. The limestone promotes more slag formation which will leads to better agglomeration and in turn higher sinter strength and also higher sinter productivity. During sintering of granules, the formation of slag increases which is indicated by sinter physical strength i.e. tumbler index. At the same time, sinter productivity also increases due to the increase in sintering kinetics with the use of such sandwich iron ore pile. The above said improvement is attributed due to the presence of limestone and its interaction with iron ore at high temperature during sintering which may result in formation of low viscous slag due to presence of excess flux near to the ore
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surface. Alternatively, the limestone also improves granulometry of green mix which subsequently improves the sinter bed permeability, flame front movement and productivity. The limestone also promotes rich formation of calcium ferrite phases during sintering which is expected to give better strength to the sinter.
Step 106 includes mixing the green mix in the mixing drum. Preferably, mixing of the green mix in the mixing drum is for a period of 5 minutes. Preferably, the green mix is dry mixed in the mixing drum at a speed of 19-20 rpm.
Step 108 includes adding green mix, coke, calcined limes, return fines and water to the granulating drum. Preferably, the moisture of green mix is maintained between 7.5 to 8.0%. Accordingly, the water is added based on the moisture of the green mix. Preferably, size of the calcined lime is 0.212 mm. Preferably, size of the coke breeze is 3.15 mm.
Step 110 includes granulating the green mix, coke, calcined limes, return fines and water in the granulating drum to form granules. Preferably, granulating the green mix in the granulating drum is performed for 5 minutes. The whole materials are wet mixed in granulating drum for a duration of 5 minutes at a speed of 19-20 rpm. The green mix granules are in the size range of ~2-3 mm. Alternatively; the limestone inhibits absorption of water into the iron ores. The limestone forms a slurry when water is added in the granulating drum. Alternatively, the limestone also acts as a binder to improve the adhesion of iron ore particles in the green mix during granulation and/or the structural integrity of the granules in the different regions of the sinter bed during sintering, such as in the drying zone and the moisture condensation zone of the sinter bed.
Step 112 includes sintering the granules. Then the top layer of sinter bed is heated with the gas based fuel for duration of 90-120 seconds. At the same time, the negative suction pressure below the sinter bed is maintained at 400-500 mm
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Water Column for duration of 90-120 seconds. After 120 seconds of top layer firing, the negative suction pressure increased to 1200-1300 mm Water Column.
Alternatively, the limestone may be also added in any suitable manner during the sintering process. By way of example, the limestone can be: (i) dissolved in the water and added to the granulating drum; (ii) added as a solid into the greenmix in the granulating drum.
More particularly, the present disclosure is directed to provide a novel process to deal with all types of iron ore having different chemical, physical and phase characteristics like limonite, goethite, hematite, dense and porous iron ore to achieve better sinter productivity and quality.
In an embodiment, the process of sintering iron ore can be an online or offline process.
A major advantage of this process is that it will overcome the detrimental impact of limonite, goethite, and porous characteristics of iron ore in the sintering process.
The present invention is described further hereinafter by reference to a series of examples.
Experiments that were actually performed are now described by way of following examples:
Example I: Components in percentage by weight The following amount of iron ore, limestone, dolomite, coke, return fine and calcined lime wasused for sintering by conventional methodas well as sintering by the process of the present advancement through experiments 1-6 comprising of Porous/Soft Iron Ore and Dense/Hard Iron Ore having composition of raw mix as shown in Table 1. These samples are sintered by conventional method (Example
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II) and sintering by the process of the present invention (Example III). Table 2 illustrate the chemical analysis of the composition of Samples.
Three types of iron ore are used to validate the novel process through experiments, their names are as under:
1. Dense Iron ore 2. Porous Iron ore 3. Goethite Iron ore
The blend compositions for the experiments under the example are given as under:
Table 1:
Raw materials Expt-1 Expt-2 Expt-3 Expt-4 Expt-5 Expt-6 Dense I/O 61.6 61.6 0 0 0 0 Porous I/O 0 0 61.6 61.6 0 0 Goethite I/O 0 0 0 0 61.6 61.6 Return Fines 18 18 18 18 18 18 Limestone 6.9 6.9 6.9 6.9 6.9 6.9 Dolomite 7.5 7.5 7.5 7.5 7.5 7.5 Calcined Lime 1.8 1.8 1.8 1.8 1.8 1.8 Coal/Coke 4.2 4.2 4.2 4.2 4.2 4.2 Total 100 100 100 100 100 100
The blend composition is decided based upon the chemical analysis of the raw materials and the requirement from blast furnace. The fluxes are added to maintain basicity (CaO/SiO2 ratio) of sinter.
The chemical analysis of the raw materials used for the present investigation is given below in Table 2.
Table-2: Chemical Analysis of Raw Materials: Blend Fe(T) FeO SiO2 Al2O3 CaO MgO LOI Goethite I/O 57.47 -- 5.69 2.79 0.10 0.06 8.21 Dense I/O 63.77 -- 2.87 2.41 0.76 0.24 2.22 Porous I/O 64.94 -- 2.02 1.09 0.33 0.45 2.39 Return fines 53.59 6.15 6.15 3.25 11.95 2.12 --
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Limestone 0.89 -- 2.05 0.47 50.49 2.73 42.59 Dolomite 0.79 -- 5.22 0.67 29.05 19.49 43.97 Calcined Lime 0.31 -- 0.81 0.28 93.94 1.49 3.05 Ash VM S Fixed Carbon Coke breeze/Coal 12.6 3.18 0.42 84.23
The mineralogy and physical characteristics of input materials vary with their originating place.
Due to the drastic change in chemical analysis of iron ore, iron ores with varying compositions are sintered. A blend of two or more iron ores are also carried out to achieve the required chemistry of the material.
Example II: Sintering the Iron Ore by Conventional Method Firstly, the limestone, iron ore, dolomite and coke were mixed homogeneously to form a green mix. Secondly, the green mix was mixed in the mixing drum. Approximately 90 kg of green mix blended using the balling drum. The green mix was mixed at the speed of 20 rpm for 300 seconds. Thirdly,the green mix, coke, calcined limes, return fines and water was charged charged in the granulating drum and subjected to granulation to form granules. The granulation was done at the speed of 20 rpm for 480 seconds. Fourthly, the granules were charged on the sinter bed and the granules were then sintered. The sinter bed height is maintained constant at 700 mm and hearth layer at 60 mm. Table 3 shows the ignition conditions of sinter bed.
Table 3: Ignition Conditions Suction air flow volume before ignition 2.0 m3/min Ignition holding time 60 sec Suction pressure after ignition -1200 mm H2O
The sintering of the iron ore by conventional method was performed separately for each sample as in Table 1 .
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Example III: Sintering the Iron Ore by the Process of the Present invention
Firstly, a pile was made by layering limestone, iron ore dolomite and coke. The iron ore was sandwiched between the limestone and dolomite. Secondly, the limestone, iron ore, dolomite and coke were mixed homogeneously to form a green mix. Thirdly, the green mix was mixed in the mixing drum. Approximately 90 kg of green mix blended using the balling drum. The green mix was mixed at the speed of 20 rpm for 300 seconds. Fourthly, the green mix, coke, calcined limes, return fines and water was added to the granulating drum. The coke, calcined limes and/ return fines were added as per the amount mentioned in Table1.Fifthly, the green mix, coke, calcined limes, return fines and water was mixed in the granulating drum to form granules. The granulation was done at the speed of 20 rpm for 480 seconds. Lastly, the granules were charged on the sinter bed and the granules were then sintered. The sinter bed height is maintained constant at 700 mm and hearth layer at 60 mm. Table 3 shows the ignition conditions of sinter bed. The sintering of the iron ore by above method was performed as per Table 3 separately for each sample as in Table 1 .
Example IV: Tumbler Index and Productivity
The tumbler Index is a relative measure of the resistance of the material to breakage or degradation by impact. The tumbler index test complies with the standard ISO 3271:2015.ISO 3271:2015 specifies a method to provide a relative measure for evaluating the resistance of iron ores to size degradation by impact and abrasion. It covers the determination of the tumble and abrasion indices.This International Standard is applicable to lump ores, sinters, and hot-bonded pellets.
The sintered iron ore was crushed. The tumbler index and productivity tests were carried out.
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The important parameters to consider with respect to quality and sintering performance are tumbler index and sinter productivity. The sintering parameters are given below in Table 4:
Table 4:
Results
Expt1 Expt2 Expt3 Expt4 Expt5 Expt6 Dense I/O Porous I/O Goethite I/O Conv. New Conv. New Conv. New
Tumbler Index (+6.3mm, %)
72.13 73.50 75.20 77.25 74.50 76.50
Productivity (+5mm) (t/m2/h) 2.00 2.35 2.26 2.35 1.98 2.25
The sinter qualities improved while processing it through new route over conventional process. Every iron ores shown improvement in their qualities and productivity.
Thus, the sintering of iron ore by the method of the present disclosure is advantageous over the conventional method of sintering iron ore.