TECHNICAL FIELD

Present disclosure generally relates to a field of material science and metallurgy. Particularly, but not exclusively the present disclosure relates to iron ore sintering process. Further, embodiments of the disclosure disclose a method of agglomerating carbon rich coke breeze fines for iron ore sintering.

BACKGROUND OF THE DISCLOSURE
Sintering is a process which includes processes of compacting and forming solid mass of material by application of heat or pressure or both. During sintering process, application of heat or pressure is carried out in a controlled manner where the temperature and pressure are controlled just enough to a liquation temperature. Conventionally, sintering processes generally involves agglomeration of iron ore and other raw material fines into a compact mass. During sintering process, blended raw materials including such as limestone may be used. Additionally, flux material such as quartz is also used along with coke breeze as fuel. Optionally, water may be added to the iron ores and mixed with each other for granulating. The granulated mixture/ sinter mix may be then fed into sintering bed in a wet condition. During sintering, air may be sucked from a lower portion of the sintering machine underneath the sinter bed, and fuel such as coke breeze contained in the blended raw material may be burned. Therefore, fine iron ore may be melted and thus the mixture may be solidified. Later, the burning zone may be gradually shifted from the upper surface layer to the lower layer, wherein the charged iron ore gets sintered.

During normal sintering process, cold air may be sucked from the wet sinter bed. During this suction. Coke fines present in the sinter mixture may have a low wettability or low contact angle. Hence, these coke fines may get separated from the sinter mixture when in contact with down draft hot gases [suction] and tend to heterogeneously distribute across the sinter bed. This may lead to a different proportion of carbon across the sintering bed. The top portion of the sinter bed may be at a lower percentage of carbon as compared to middle portion and the bottom portion. The bottom portion which may be around 200 mm to 300 mm nearer to the suction system of sintering machine aids in much more efficient removal or suction of the coke fines. Even otherwise, the coke fines move to the bottom portion due to suction and may get separated from the sinter mixture and collected in sinter waste. Due to this, the coke content gets collected at the bottom layer as well. This heterogenous distribution of coke fines across the sintering bed may lead to a non-uniform heat generation across the sintering bed. Hence, during normal sintering, the heat pattern across the sintering bed of an actual sintering machine may be non-uniform in the vertical direction of the bed. This condition may lead to ‘heat deficiency’ at top portion of sinter bed, due insufficient presence of fuel materials at top and may cause generation of weak sinter fines leading to reduction in ‘yield’ of sinter production. Hence, during sintering process, the top portion of the sintering bed may be lower in the bulk temperature and besides shorter in length of time for exposure to elevated temperature than the middle and lower portions. This condition may lead to the problem that a sintered ore formed in the top portion may be low in melt bonding and hence poor in mechanical strength with reduced sintering yield.

Furthermore, when the flame front travels beneath the sinter bed, the top portion of sintering bed may experience the maximum amount of thermal shock. The temperature of the top portion may experience temperature drop in higher magnitude than compared to the middle and bottom portions. Hence, the top portion of sinter bed may become fragile and lead to poor sinterability. Therefore, the top portion may cool at a faster rate compared to middle and bottom portion. Additionally, presence of insufficient amount of coke fines and fast cooling rate may make the top portion of the bed weaker in strength. Due to this, the maximum amount of sinter fines i.e. (-5 mm) may be generated. The partial pressure of oxygen also may be high at the top portion and hence the coke fines would burn at faster rate in top layer as compared to middle and bottom layer. The excess available oxygen in top portion may result in conversion of wüstite into hematite, and hence the top layer may become porous and fragile. Around 20% to 30% of the total sinter bed is unusable owing to its fragile nature and hence it is always reported as return sinter fines (-5 mm).

Conventionally, many methods have been tried to avoid coke segregation. One such method includes varying flame-front speed to improve the sinterability. However, raising the flame front temperature may increase airflow resistance and lead to longer sintering times and a lower productivity. Another method employed to control the air-volume distribution along the length of the sinter bed is to control air flow in an initial length of the sinter machine and also to achieve extension of retention time of heat holding of top layer above 1100 °C. But this leads to only 11% improvement in the yield at the top portion of sintering bed. One more method known in the conventional art, employs a silica based activated mineral binder to prepare coke dry fines agglomerates. However, this method does not utilize coke breeze in maximum amount. Yet another method involves a system for enhancement of carbon and size segregation of sinter mixture in order to achieve uniform heat generation through the sinter bed height. In order to achieve this condition, a system comprising screen type charging means for segregation of sinter mixture has been employed. However, in this method an electrostatic precipitator may be required to collect micro granules of sinter mix. Hence, this method may not be economically feasible. Another method with magnetic loading of sintering material into sintering bed to improve the productivity during sintering has been tried. All these methods require extra capital and huge space working area near to the sintering area and hence makes industrially less adaptable.

The present disclosure is directed to overcome one or more limitations stated above or any other limitation associated with the conventional methods.

SUMMARY OF THE DISCLOSURE
One or more shortcomings of the prior art are overcome by a method as disclosed and additional advantages are provided through the method as described in the present disclosure. Additional features and advantages are realized through the techniques of the present disclosure. Other embodiments and aspects of the disclosure are described in detail herein and are considered a part of the claimed disclosure.

It is to be understood that the aspects and embodiments of the disclosure described above may be used in any combination with each other. Several of the aspects and embodiments may be combined together to form a further embodiment of the disclosure.

In one non-limiting embodiment of the present disclosure, there is provided a method of agglomerating carbon rich coke breeze fines for iron ore sintering. In the method, the coke breeze fines with a binder in absence of moisture, are blended to form a mixture of the coke breeze fines and the binder. Subsequently, the mixture of the coke breeze fines, and the binder is added with moisture. Later, the mixture of coke breeze fines and the binder with the moisture is granulated to form pellets. Finally, the pellets are cured to form carbon rich coke agglomerates.

In an embodiment, the mixture of the coke breeze fines and the binder with the moisture comprises about 2 wt.% to 8 wt.% of the binder, about 7 wt.% to about 8 wt.% of the moisture and remainder being the coke breeze fines.

In an embodiment, the binder is calcined lime fines and size of the calcined lime fines is about 200 mesh with at least 80% passing.

In an embodiment, addition of moisture is carried out by spraying water.

In an embodiment, granulating is carried out in at least one of enrich mixer, high intensity mixer and disc pelletizer.

In an embodiment, the granulating time ranges from about 10 minutes to about 15 minutes.

In an embodiment, the curing is carried out in ambient atmosphere.

In an embodiment, size of the pellets ranges from 0.15 mm to 6 mm.

In an embodiment, particle size of the coke breeze fines ranges from 0.25 mm to 3.15 mm.

In an embodiment, quantity of the coke breeze fines before granulation is about 68 % to about 70 % of total mass or volume of the mixture the mixture of the coke breeze fines and the binder.

In an embodiment, quantity of the coke breeze fines after granulation is about 80 % to about 85 % of total mass or volume of the mixture of the coke breeze fines and the binder with moisture.

In an embodiment, the curing affects the particle size in the carbon rich coke agglomerates.

In an embodiment, the carbon rich coke agglomerates are compounds of carbon and calcium oxide.

In an embodiment, the sinter mix comprises iron ore fines, limestone, carbon rich coke agglomerates, dolomite and moisture. The carbon rich coke agglomerates comprise coke breeze fines, calcined lime fines and moisture.

In an embodiment, the carbon rich coke agglomerates reduce coke segregation across sintering bed during the iron ore sintering.

It is to be understood that the aspects and embodiments of the disclosure described above may be used in any combination with each other. Several of the aspects and embodiments may be combined together to form a further embodiment of the disclosure.

The foregoing summary is illustrative only and is not intended to be in any way limiting. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features will become apparent by reference to the drawings and the following detailed description.

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
The novel features and characteristics of the disclosure are set forth in the appended description. The disclosure itself, however, as well as a preferred mode of use, further objectives and advantages thereof, will best be understood by reference to the following detailed description of an illustrative embodiment when read in conjunction with the accompanying figures. One or more embodiments are now described, by way of example only, with reference to the accompanying figures wherein like reference numerals represent like elements and in which:

Figure 1 is a flowchart illustrating a method of agglomerating carbon rich coke breeze fines for iron ore sintering, according to an exemplary embodiment of the present disclosure.

Figures 2a and 2b illustrate coke breeze fines and carbon rock coke agglomerates respectively, according to an exemplary embodiment of the present disclosure.

Figure 3 is a graphical representation of variation in particle size of the coke breeze fines and carbon rich coke agglomerates, according to an exemplary embodiment of the present disclosure.

Figure 4 is a graphical representation of variation in particle size of carbon rich coke agglomerates during curing, according to an exemplary embodiment of the present disclosure.

Figure 5 illustrates a schematic of the carbon segregation test facility for iron ore sintering, according to an exemplary embodiment of the present disclosure.

Figure 6 is a graphical representation of variation in carbon content across the sintering bed for the coke breeze fines and the carbon rich coke agglomerates, according to an exemplary embodiment of the present disclosure.

Figures 7a and 7b illustrate a schematic representation of coke segregation during sintering using the coke breeze fines and the carbon rich coke agglomerates, according to an exemplary embodiment of the present disclosure.

Figure 8 is a schematic representation of process of iron ore sintering, according to an exemplary embodiment of the present disclosure.

The figures depict embodiments of the disclosure for purposes of illustration only. One skilled in the art will readily recognize from the following description that alternative embodiments of the methods illustrated herein may be employed without departing from the principles of the disclosure described herein.

DETAILED DESCRIPTION

The foregoing has broadly outlined the features and technical advantages of the present disclosure in order that the detailed description of the disclosure that follows may be better understood. Additional features and advantages of the disclosure will be described hereinafter which form the subject of the description of the disclosure. It should also be realized by those skilled in the art that such equivalent methods do not depart from the scope of the disclosure. The novel features which are believed to be characteristic of the disclosure, as to method of operation, together with further objects and advantages will be better understood from the following description when considered in connection with the accompanying figures. It is to be expressly understood, however, that each of the figures is provided for the purpose of illustration and description only and is not intended as a definition of the limits of the present disclosure.

In the present document, the word "exemplary" is used herein to mean "serving as an example, instance, or illustration." Any embodiment or implementation of the present subject matter described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments.

While the disclosure is susceptible to various modifications and alternative forms, specific embodiment thereof has been shown by way of example in the drawings and will be described in detail below. It should be understood, however that it is not intended to limit the disclosure to the particular forms disclosed, but on the contrary, the disclosure is to cover all modifications, equivalents, and alternative falling within the spirit and the scope of the disclosure.

The terms “comprises”, “comprising”, or any other variations thereof, are intended to cover a non-exclusive inclusion, such that a method that comprises a list of acts does not include only those acts but may include other acts not expressly listed or inherent to such method. In other words, one or more acts in a method proceeded by “comprises… a” does not, without more constraints, preclude the existence of other acts or additional acts in the method.

Conventional coke breeze fines employed in iron ore sintering may heterogeneously distribute along a top section, a middle section and a bottom section of a sintering layer leading to carbon segregation. Due to heterogeneous distribution of coke, the top layer or top section may be depleted of fuel in comparison to the middle and bottom sections. This situation may cause insufficient heat at the top layer or sections and non-uniform flame front along the sinter bed. Moreover, this causes poor heat distribution profile leading to uneven sintering across the sinter bed thereby leading to poor sinterability. The top section may also lead to porous and low strength sinters compared to the bottom layer. Thermal stresses may be higher at the top layer due to irregular heat distribution.

From the prior arts, it is evident that obtaining uniform coke distribution during iron ore sintering to obtain improved sinterability by avoiding carbon segregation is still a challenge.

The present disclosure provides a method of agglomerating carbon rich coke breeze fines for iron ore sintering. In this method, the coke breeze fines are provided with a binder, wherein the binder is introduced in absence of moisture. Later these compounds are blended to form a mixture of the coke breeze fines and the binder. Subsequently, the mixture of the coke breeze fines, and the binder is added with moisture or sprinkled with moisture. Later, the mixture of coke breeze fines and the binder with the moisture is granulated to form pellets. Finally, the pellets are cured to form carbon rich coke agglomerates. The carbon rich coke agglomerates are then mixed with the sinter mix which aids in avoiding carbon segregation across the sintering bed and thereby improve overall sinterability during iron ore sintering.

In the following detailed description of the embodiments of the disclosure, reference is made to the accompanying drawings that form a part hereof, and in which are shown by way of illustration specific embodiments in which the disclosure may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the disclosure, and it is to be understood that other embodiments may be utilized and that changes may be made without departing from the scope of the present disclosure. The following description is, therefore, not to be taken in a limiting sense.

In the present disclosure a method of agglomerating carbon rich coke breeze fines for iron ore sintering is explained with the help of figures. However, such exemplary embodiments should not be construed as limitations of the present disclosure, since the method may be used for other types of agglomerations other than coke breeze fines. A person skilled in the art may envisage various such embodiments without deviating from scope of the present disclosure.

Figure 1 is a flow chart illustrating steps involves in a method of agglomerating carbon rich coke breeze fines for iron ore sintering. The method may be particularly applicable for producing pellets of size ranges from 0.15 mm to 6 mm. At block 101, coke breeze fines of size from 0.25 mm to 3.15 mm and a binder is blended in a disc pelletizer in absence of moisture to form a mixture of the coke breeze fines and the binder. It is to be understood that the size limitation of the coke breeze fines is just indicative and should not be construed as limitation. However, it is important to note that, the size of these coke breeze fines may increase or decrease based on requirement. In an embodiment, the binder is calcined from lime fines and size of the calcined lime fines is about 200 mesh with at least 80% passing. Later, the mixture of the coke breeze fines, and the calcined lime fines are added with moisture in a disc pelletizer as shown in block 102. The moisture is introduced by spraying water into the mixture at a predetermined quantity. In the next step, the mixture of the coke breeze fines and the binder with the moisture is granulated to form pellets as shown in block 103. In an embodiment, as the mixture of coke breeze fines and the binder are mixed, they are subjected to granulation in a granular mixer or pelletizer. The pelletizer may be any one of a disc pelletizer, a drum pelletizer and the like. The mixture of the coke breeze fines and the binder with the moisture comprises about 2 wt.% to 8 wt.% of the binder, about 7 wt.% to about 8 wt.% of the moisture and remainder being the coke breeze fines. The process of granulating the mixture of the coke breeze fines, and the calcined lime fines and moisture is carried out in at least one of an enriched mixer, a high intensity mixer and a disc pelletizer. The granulating time ranges from about 10 minutes to about 15 minutes, again the same cannot be considered as a limitation, as this time can vary based on the size of the sinter mix. Furthermore, quantity of the coke breeze fines before granulation is about 68 % to about 70 % of total mass or volume of the mixture of the coke breeze fines and the binder. However, quantity of the coke breeze fines after granulation is about 80 % to about 85 % of total mass or volume of the mixture of the coke breeze fines and the binder with moisture. This increase is mainly contributed to the moisture absorption. Finally, as shown in block 104 the pellets are cured to form the carbon rich coke agglomerates. The curing is carried out in ambient atmosphere for 1 to 7 days.

Figures 2a an 2b depict the schematic of the coke breeze fines prior to agglomeration [figure 2a] and the carbon rich coke agglomerates formed after agglomeration process [figure 2b] using method as disclosed in the present disclosure. These carbon rich coke agglomerates are compounds of the carbon and the calcium oxide (CaO) that reduce the coke segregation across the sintering bed during the iron ore sintering.

Referring now to figure 3 which illustrates the graphical representation of variation in particle size for the coke breeze fines and the carbon rich coke agglomerates. From figure 3, it is clearly seen that the carbon rich coke agglomerates exhibit narrow particle size distribution compared to wider particle distribution observed in case of normal coke breeze fines without subjecting to any aggregation process. Furthermore, fine particles of the carbon rich coke agglomerates having size 0.15 mm and -0.15 mm have been reduced to a large extent indicating good quality of agglomerates. However, decreased amount of fine particles may lead to decreased sinter returns mainly obtained from bottom portion of sintering bed.

In an embodiment, effect of curing time on fines of coke agglomeration is illustrated in a graphical representation as show in Figure 4. The carbon rich coke agglomerates are cured for 1 to 7 days under normal atmospheres. As seen from the Figure 4 it is noticeable that with increase in curing time, -0.5 mm sized particles increase by 2 % when compared to initial value.

Following paragraphs now enumerates examples of carbon rich coke agglomerates using a method of the present disclosure:

EXAMPLES:

Case 1: Carbon segregation test for iron ore sintering at laboratory scale.

In an exemplary embodiment, the magnitude of carbon segregation across the sinter bed may be studied for normal coke breeze fines and the carbon rich coke agglomeration produced by the method of present disclosure, using carbon segregation testing at laboratory scale. Figure 5 depicts carbon segregation test facility for an iron ore sintering. Charging of the sinter base mix into an apparatus may be done in separate trials using normal coke breeze and carbon rich coke agglomerates. The sinter bed height may be maintained at around 600 mm and hearth layer of 50 mm height may be adopted at a bottom section. An ignition hood provided at the top of the sinter bed may help to generate hot air blast. The suction across the sinter bed may be maintained at around 1200 mm of the water column. The testing may be carried out for about around 25 minutes. During testing, percentage of carbon variation may be measured in various locations in the sinter bed (1 to 9) as indicated in figure 5.

Referring now to figure 6, a graphical representation of variation in carbon content across sintering bed for coke breeze fines and carbon rich coke agglomerates is depicted. It is clearly seen that, while sintering of normal coke breeze, the top potion of the sintering bed may be depleted of carbon. Further, carbon segregation at the middle portion may be more comparable to the bottom portion of the sinter bed. The coke in the bottom portion may accumulate as the carbon dust leading to carbon loss occurs during sintering process. This condition may lead to increase in overall carbon rate requirement during the sintering process. However, a uniform carbon distribution is achieved when the carbon rich coke agglomerates prepared by the method as disclosed in the present discourse. Every location in sinter bed may have nearly equal percentage of carbon variation indicating homogenous distribution of the coke without forming to any segregation. Hence, presence of carbon rich coke agglomeration may greatly reduce the carbon segregation across the sintering bed.

In an embodiment, figures 7a and 7b illustrate schematic representation of the coke segregation during sintering by using the coke breeze fines and the carbon rich coke agglomerates. As shown in figure 7a, it is estimated that the fine sized coke breeze may get segregated in the middle portion of the sinter bed, and the increase in the carbon content in the middle portion of bed is due to the transfer of coke from the top portion of bed of the sinter bed. Further, the top portion of sinter bed may become depleted of the coke fines, due to the suction during sintering. Subsequently, the carbon in the bottom potion of the sinter bed also get sucked as it is closest to the suction system. Hence, a heterogenous distribution of carbon may be occur across the sinter bed. On the other hand, the carbon rich coke agglomerates produced using method of the present disclosure may control the segregation across the sinter bed as shown in figure 7b.

Case II: Carbon segregation test for iron ore sintering at sintering plant.

In an exemplary embodiment, the magnitude of carbon segregation across the sinter bed may be studied with carbon rich coke agglomeration in the iron sintering plant.

In trial I, 100 kg sinter mix was mixed in a drum such as a rotary mixing drum, wherein the compositions include normal coke breeze fines (un-agglomerated) iron ore fines, lime, sinter return fines and moisture. Similarly in trial II, 100 kg sinter mix was be prepared using iron ore fines, limestone, carbon rich coke agglomerates (prepared by a method of present disclose), dolomite or pyroxenite, sinter return fines and moisture stored in individual bins A, B, C, D, E respectively as shown in Figure 8. The sinter mix may be subjected to uniform mixing in a granulator drum or a rotary mixing drum for a granulated mixture. This sinter mix may be later transformed into a feeding hopper of sinter plant straight grate furnace. The feeding hopper then feeds the granulated mixture into a pallet car of a sinter pot to form a sinter bed. Hearth layer sinter bins were used to layer the granulated mixture on the pallet car. Total height of sintering bed was 600 mm with top, middle and bottom portions each at a distance of about 200 mm. This unsintered granulated mixture present on the pallet car was made to move in a forward direction. When the sinter bed come under induration furnace, top portion of the sinter bed may get ignited. Hot air was made to pass at from the top portion of sinter bed at 120-150 °C for about 30 minutes. A suction generator system present underneath of the sinter bed. The section generator system basically contains two values. One valve which is near initial ignition which was be maintained at 600 mm of water column pressure. This valve was kept at 100 percentage open throughout the sintering process. A second value for remaining length of sintering process may be maintain at 1200 mm of water column pressure. In the beginning of section operation, the second valve was kept 100 % opened state; later at an interval of about 1 minute to 2 minutes, the second value was closed to 30 %, 60% and 100 %. The value may remain 100 % closed for next 20 seconds to 30 second and then once again kept 100 % opened state. After ignition, flame front generated may travel downwards from top portion to bottom portion of sinter bed and when the amount of heat may be sufficiently high as 1200 °C sintering of iron ore may take place. The heating rate, cooling rate including controlling of retention time of flame front may be controlled based on the time of opening and closing of second value of section generator. Hot air sucked by suction generator system may be supplied to a gas cleaning unit. Sintered iron ore may be separated using + 5 mm and -5 mm screen.

Screen Size, mm +6 -6, +5 -5+,3.15 -3.15, +2 -2, +1 -1+0.25 -0.25
Wt. % carbon as per size Top 9 18 19 20 14 9 11
Middle 5 14 12 22 8 14 25
Bottom 7 14 12 20 18 15 14

Table-1

Table 1 tabulates size wise weight % carbon in sinter base mix with normal coke breeze for trial I. Here, the coke fines so added are in un agglomerated condition. From the table 1, it is clear that the fine fraction of coke fines mainly below 1 mm is around 20 % in top portion and around 39 % in the middle portion which reveals that the carbon in finer fraction travels to the middle section from the top section of the sinter mix. However, in case of the bottom portion of the bed, the coke fines fraction is 29 % being still more than top bed as carbon get accumulated in sinter dust.

In order to control the above limitation of coke segregation in sintering process, the fuel mainly coke breeze fines are converted in agglomerates according to the method as disclosed in present disclosure.

Size +6 -6, +5 -5+,3.15 -3.15, +2 -2, +1 -1+0.25 -0.25
Wt. % carbon as per size Top 9 18 20 23 18 8 4
Middle 11 16 19 27 16 6 5
Bottom 8 16 22 21 26 4 3

Table-2

Table 2 tabulates size wise weight % carbon in sinter base mix with carbon rich agglomerated coke breeze during trail II. It is clear that -1 mm fraction in the top, middle and bottom portions of the sintering bed of the dried sinter mix is in the range of about 7% to about 12% which is largely reduced owing to lower fraction of fines available in carbon rich agglomerate of coke breeze. It is also found that the fired sinter density may be about 3.4 g/cc to about 3.9 g/cc for sintering process using carbon rich coke agglomerates compared to about 3.1 g/cc to about 3.3 g/cc in normal sintering process.

Referring to figure 8, the sinter mix comprises compositions of iron ore fines, limestone, coke breeze, dolomite or pyroxenite, burnt line or calcined lime and some return fines. These compositions are stored in individual bins [A, B, C, D, E] as shown in figure 8. It is important to note that the percentage composition of the above-mentioned composites may vary based on requirement. To these composites stored in the bins [A, B, C, D, E], a mixture of coke breeze fines, lime fines and moisture are added. Further, the above-mentioned mixtures are transferred to a bin (F) shown in figure 8 and which are then transferred to the rotating drum in order to form the sinter mix.

In an embodiment, carbon rich coke agglomerates obtained from the method as disclosed in present disclosure may avoid carbon segregation by providing homogeneous carbon distribution across top, middle and bottom section of the sinter bed. Homogenous distribution coke may also provide uniform flame front across the sintering bed. These conditions may lead to improved sinterability. The present disclosure may be thus successful in providing a simple, easy, economic and efficient method of carbon rich agglomerating coke breeze fines for iron ore sintering.

Equivalents:

With respect to the use of substantially any plural and/or singular terms herein, those having skill in the art can translate from the plural to the singular and/or from the singular to the plural as is appropriate to the context and/or application. The various singular/plural permutations may be expressly set forth herein for sake of clarity.

It will be understood by those within the art that, in general, terms used herein, and especially in the appended claims (e.g., bodies of the appended claims) are generally intended as "open" terms (e.g., the term "including" should be interpreted as "including but not limited to," the term "having" should be interpreted as "having at least," the term "includes" should be interpreted as "includes but is not limited to," etc.). It will be further understood by those within the art that if a specific number of an introduced claim recitation is intended, such an intent will be explicitly recited in the claim, and in the absence of such recitation no such intent is present. For example, as an aid to understanding, the following appended claims may contain usage of the introductory phrases "at least one" and "one or more" to introduce claim recitations. However, the use of such phrases should not be construed to imply that the introduction of a claim recitation by the indefinite articles "a" or "an" limits any particular claim containing such introduced claim recitation to inventions containing only one such recitation, even when the same claim includes the introductory phrases "one or more" or "at least one" and indefinite articles such as "a" or "an" (e.g., "a" and/or "an" should typically be interpreted to mean "at least one" or "one or more"); the same holds true for the use of definite articles used to introduce claim recitations. In addition, even if a specific number of an introduced claim recitation is explicitly recited, those skilled in the art will recognize that such recitation should typically be interpreted to mean at least the recited number (e.g., the bare recitation of "two recitations," without other modifiers, typically means at least two recitations, or two or more recitations). Furthermore, in those instances where a convention analogous to "at least one of A, B, and C, etc." is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (e.g., "a system having at least one of A, B, and C" would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). In those instances where a convention analogous to "at least one of A, B, or C, etc." is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (e.g., "a system having at least one of A, B, or C" would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). It will be further understood by those within the art that virtually any disjunctive word and/or phrase presenting two or more alternative terms, whether in the description, claims, or drawings, should be understood to contemplate the possibilities of including one of the terms, either of the terms, or both terms. For example, the phrase "A or B" will be understood to include the possibilities of "A" or "B" or "A and B."

While various aspects and embodiments have been disclosed herein, other aspects and embodiments will be apparent to those skilled in the art. The various aspects and embodiments disclosed herein are for purposes of illustration and are not intended to be limiting, with the true scope and spirit being indicated by the following claims.

Referral Numerals

Referral Numerals Description
101 Blending
102 Wetting
103 Granulating
104 Curing

We claim:

1. A method of agglomerating carbon rich coke breeze fines for iron ore sintering, the method comprising:
blending, coke breeze fines with a binder in absence of moisture, wherein the blending forms a mixture of the carbon rich coke breeze fines and the binder;
adding moisture to the mixture of the carbon rich coke breeze fines and the binder;
granulating the mixture of the carbon rich coke breeze fines and the binder with the moisture to form pellets; and
curing the pellets to form the carbon rich coke agglomerates.

2. The method as claimed in claim 1, wherein the mixture of the coke breeze fines and the binder with the moisture comprises about 2 wt.% to 8 wt.% of the binder, about 7 wt.% to about 8 wt.% of the moisture and remainder being the coke breeze fines.

3. The method as claimed in claim 1, wherein the binder is calcined lime fines.

4. The method as claimed in claim 3, wherein size of the calcined lime fines is about 200 mesh with at least 80% passing.

5. The method as claimed in claim 1, wherein addition of moisture is carried out by spraying water.

6. The method as claimed in claim 1, wherein granulating is carried out in at least one of enrich mixer, high intensity mixer and disc pelletizer.

7. The method as claimed in claim 1, wherein the granulating time ranges from about 10 minutes to about 15 minutes.

8. The method as claimed in claim 1, wherein the curing is carried out in ambient atmosphere.

9. The method as claimed in claim 1, wherein size of the pellets ranges from 0.15 mm to 6 mm.

10. The method as claimed in claim 1, wherein particle size of the coke breeze fines ranges from 0.25 mm to 3.15 mm.

11. The method as claimed in claim 1, wherein quantity of the coke breeze fines before granulation is about 68 % to about 70 % of total mass or volume of the mixture the mixture of the coke breeze fines and the binder.

12. The method as claimed in claim 1, wherein quantity of the coke breeze fines after granulation is about 80 % to about 85 % of total mass or volume of the mixture of the coke breeze fines and the binder with moisture.

13. The method as claimed in claim 1, wherein the curing affects the particle size in the carbon rich coke agglomerates.

14. The method as claimed in claim 1, wherein the carbon rich coke agglomerates are compounds of carbon and calcium oxide (CaO).

15. The method as claimed in claim 1, wherein the sinter mix comprises compositions of iron ore fines, limestone, carbon rich coke agglomerates, dolomite and moisture.

16. The method as claimed in claim 15, wherein the carbon rich coke agglomerates comprises compositions of coke breeze fines, calcined lime fines and moisture.

17. The method as claimed in claim 1, wherein the carbon rich coke agglomerates reduce coke segregation across sintering bed during the iron ore sintering.