A DOUBLE CONE COAL CRUSHER TO ENHANCE MACERAL LIBERATION IN COAL FOR COKING
FIELD OF INVENTION:

[001] The present subject matter described herein, relates to a cone crusher used for comminution of ores. The present subject matter in particularly relates to a double cone coal crusher to enhance maceral liberation of coal particles to improve coking potential of coal.
BACKGROUND AND PRIOR ART AND PROBLEM IN PRIOR ART:
[002] Background description includes information that may be useful in understanding the present invention. It is not an admission that any of the information provided herein is prior art or relevant to the presently claimed invention, or that any publication specifically or implicitly referenced is prior art.
[003] Coke is utilized as a major fuel in producing pig iron in blast furnace. The coke making process accounts for majority of costs involved in a steel plant. In coke making process, coal is converted into coke which have highly porous strong structure with almost 90% of carbon. The steps involved in coke making process are:
1. Coal sourcing/ coal beneficiation
2. Coal blending
3. Coal crushing
4. Coal charging in the oven
5. Heating of coal mass in the absence of air
6. Pushing and collection of coke
7. Quenching the hot coke produced
8. Transport to blast furnace for use
[004] Quality of coke majorly depends upon the chemical structure of the coal. Better the quality of coke, better is the coking potential. But coking potential of coal can be enhanced by improving different processing and operational variables of the coke making process. One such variable is crushing of coal particles.
[005] Coals are organic detrital sedimentary rocks originating from a variety of plant material and different tissues along with dispersion of mineral matter. Embedded together coal forms a highly heterogeneous structure. The structure of coal can be understood by dividing the same into three macerals (vitrinite, inertinite, liptinite) and ash/mineral constituents. The macerals compositions are the categories which can be underlined for understanding coking potential of coal. The vitrinite contributes majorly for defining the coking potential of a coal. But it’s just not the presence of the macerals that contribute in the coke making, the positioning or the way they are dispersed in coal plays an important role in coke making.
[006] Vitrinite and exinite are viscoelastic solids. When force is applied to them, they undergo a temporary deformation with a gradual return to the initial state on release of force, and a permanent viscous deformation which is considerable for vitrinites of medium rank if shattering of the particle is avoided. During coke making, as the temperature rises the viscoelasticity of these macerals contributes towards the softening and this enhance coking.
[007] But the exposure of the vitrinites in normal conditions is restricted due to either the tectonic movements or due to the industrial mining & crushing processes which shatters/breaks the particle in a random manner and the thereby results in the lower coking properties.
[008] Existing crushing mills can be broadly classified as impact-attrition, compression-attrition, or attrition mills based on the forces. Highest strain rates are induced in the impact mills. In these kinds of mills, the momentum is transferred from the rotating media on to the particles. Mostly all the impact mills transfer their high inertia on to the particles to cause fracture. As a result, high stress values are applied on to a particle for a smaller residence time and the crack growth happens randomly through the media and non-uniform product is obtained depending on the parent particle. This kind of the behavior can be seen typically in mills which operate on impact phenomena such as hammer mills, ball mills, rod mills, jet mills, etc. Conventionally, coke plant operations deploy hammer mills for coal processing due to low maintenance and stabilized operations.
[009] For applying slower strain rates, slow speed mills like roller mill, vertical roller mill, cone crusher etc., are extensively used based on the feed and product sizes. But, in terms of coke making the granulometry of the particles is of great importance, particularly in the case of stamp charged coke making. For coke making applications the size of coal particles for stamp charged should have a mean size less than 1mm and in case of top charged it should be in the range of 1.5-1.8mm. These size fractions can be obtained from the hammer mills and roller mills. Impact mills like hammer mills can produce the particle size distributions but the nature of the forces shatters the reactive macerals. The impact mills like ball mills create very fine product. The roller mills can produce a controlled particle size distribution but the directionality of forces along with the magnitude again produces grain with higher sphericity and elongation of the reactive macerals is not observed.
[0010] While cone crushers in the prior art are used majorly for coarser crushing applications in the mining industries. Some other hybrid type of cone crushers is also being reported which can be used for fine grinding with efficient energy usage. Cone crushers if used with appropriate geometries could produce size applicable for coke making applications. But these cone mills have inner cone as a gyrating mandrel which imparts compression and impact forces onto the particles which needs to be broken. The gyration helps for the energy conservation but doing so energy is transferred in impact mode to the particles and thus shatter the particles into finer size fractions. Cone crusher mills with gyrating action come with two co-axial cones with one or the other cone as gyrating member. Generally, for coarser crushing applications outer cone has a gyrating axis and for finer grinding inner cone is kept as a gyration member.
[0011] It is an object of the invention to provide a double cone coal crusher which overcomes the impact phenomenon by removing the gyratory member whilst providing specially grooved shear pads on the surfaces of inner and outer cone.
[0012] The information disclosed in this background of the disclosure section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.

OBJECTS OF THE INVENTION:
[0013] It is therefore the object of the invention to overcome the aforementioned and other drawbacks in prior method/product/apparatus.
[0014] The principal objective of the present invention is to develop a double cone coal crusher to enhance maceral liberation of coal particles to improve coking potential of coal.
[0015] Another object of the present invention is to develop a double cone coal crusher to break the coal particles in shear mode by application of surficial and bodily shear forces.
[0016] Another object of the present invention is to develop a double cone coal crusher to achieve particle size distribution for stable coal cake with varying feed sizes.
[0017] Yet another object of the present invention is to develop a double cone coal crusher to increase the number of cutting surfaces and increase the feed size range of the particles.
[0018] These and other objects and advantages of the present subject matter will be apparent to a person skilled in the art after consideration of the following detailed description taken into consideration with accompanying drawings in which preferred embodiments of the present subject matter are illustrated.

SUMMARY OF THE INVENTION:
[0019] Solution to one or more drawbacks of conventional coal crushers, and additional advantages are provided through the double cone coal crusher as claimed in the present disclosure. Additional features and advantages are realized through the technicalities of the present disclosure. Other embodiments and aspects of the disclosure are described in detail herein and are considered to be a part of the claimed disclosure.
[0020] The presented subject matter discloses a double cone coal crusher with special shear pads which fracture the coal particles in shear mode. The cones are fabricated with unique design which makes easier for maintenance. The removable design of shear pads makes opportunity to use different geometric configurations & materials. Double cone coal crusher tackles the problem of slow deformation rates for coal crushing with respect to coke making applications. By applying the forces on the coal particles in a specified magnitude and direction better liberation of macerals along with particle size reduction is obtained.
[0021] According to one of the embodiment, the double cone coal crusher includes, a feed hopper to feed coal in the cone type coal crusher; a crushing unit positioned below the feed hopper; a drive unit to drive the crushing unit, the drive unit includes a gear box assembly having input end driven by a motor and output end connected to a transmission belt; and a product collection unit positioned below the crushing unit comprising a product collection hopper, a discharge chute and a plurality of scrapper blades to move the enhance maceral liberated crushed coal out from the discharge chute; wherein the crushing unit includes an inner cone having bottom end mounted on a bottom cone screw with matching threads to adjust the height of the inner cone, wherein a plurality of outer shear pads are provided on the outer surface of the inner cone; an outer cone placed coaxially outside the inner cone having bearing on both bottom and top end, wherein top end bearing is in connection with the transmission belt which provide the outer cone rotating motion and wherein a plurality of inner shear pads are provided on inner surface of the outer cone.
[0022] In an aspect, the inner cone has fixtures holes on its outer surface to accommodate the plurality of inner shear pads.
[0023] In an aspect, each shear pad of the plurality of outer shear pads is machined out from metal blocks, with different radius, to cover rows of differential curvature on the outer surface of the inner cone.
[0024] In an aspect, the mounting surface of the plurality of outer shear pads are plain and machined to gain the convexity to match the surface of inner cone and cutting surface has a plurality of grooves forming cutting edges giving serrated configuration to cutting surface, to obtain defined gap in the crushing space.
[0025] In an aspect, the plurality of outer shear pads are arranged on the inner cone in a circumferential staggered manner to avoid vertical alignment of edges of corresponding outer shear pads.
[0026] In an aspect, the outer cone has fixtures holes on its inner surface to accommodate the plurality of inner shear pads.
[0027] In an aspect, each shear pad of the plurality of inner shear pads is machined out from a metal blocks with different radius, to cover differential curvature of the inner surface of the outer cone.
[0028] In an aspect, the metal of the metal blocks is a specialized metal which can resist the aberration caused by the coal.
[0029] In an aspect, the mounting surface of the plurality of inner shear pads are plain and machined to gain the concavity to match the surface of outer cone and cutting surface has a plurality of grooves forming cutting edges, to obtain defined gap in the crushing space.
[0030] In an aspect, the plurality of inner shear pads are arranged on the outer cone in a circumferential staggered manner to avoid vertical alignment of edges of corresponding inner shear pads.
[0031] In an aspect, the feeder hopper is one of standard vibratory feeder or bucket elevator.
[0032] In an aspect, the motor is a variable frequency drive motor mounted on the exterior frame of the double cone coal crusher, having shaft parallel to the cone shaft.
[0033] 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 DRAWINGS
[0034] It is to be noted, however, that the appended drawings illustrate only typical embodiments of the present subject matter and are therefore not to be considered for limiting of its scope, for the invention may admit to other equally effective embodiments. The detailed description is described with reference to the accompanying figures. In the figures, a reference number identifies the figure in which the reference number first appears. The same numbers are used throughout the figures to reference like features and components. Some embodiments of system or methods or structure in accordance with embodiments of the present subject matter are now described, by way of example, and with reference to the accompanying figures, in which:
[0035] Fig. 1a illustrates front view of double cone coal crusher, according to one of the embodiment of present subject matter;
[0036] Fig. 1b illustrates side view of the double cone coal crusher, according to one of the embodiment of present subject matter;
[0037] Fig. 2 illustrates cross sectional view of double cone coal crusher, according to one of the embodiment of present subject matter;
[0038] Fig. 3a and 3b illustrates inner cone without shear pads and with shear pads, respectively, according to one of the embodiment of present subject matter;
[0039] Fig. 4 illustrates cross sectional view of the inner cone, according to one of the embodiment of present subject matter;
[0040] Fig. 5 illustrates outer shear pads for the inner cone, according to one of the embodiment of present subject matter;
[0041] Fig. 6 illustrates outer cone exterior and cut section view without shear pad assembly, according to one of the embodiment of present subject matter;
[0042] Fig. 7 illustrates inner shear pads for the outer cone, according to one of the embodiment of present subject matter;
[0043] Fig. 8 illustrates assembled outer cone with shear pads, according to one of the embodiment of present subject matter;
[0044] Fig. 9 illustrates assembled inner and outer core assembly, according to one of the embodiment of present subject matter; and
[0045] Fig. 10 illustrates top view of outer cone with assembled shear pads, according to one of the embodiment of present subject matters.
[0046] The figures depict embodiments of the present subject matter for the purposes of illustration only. A person skilled in the art will easily recognize from the following description that alternative embodiments of the structures and methods illustrated herein may be employed without departing from the principles of the disclosure described herein.

DESCRIPTION OF THE PREFERRED EMBODIMENTS:
[0047] While the embodiments of the disclosure are subject to various modifications and alternative forms, specific embodiment thereof have been shown by way of example in the figures and will be described 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 scope of the disclosure.
[0048] The terms “comprises”, “comprising”, or any other variations thereof used in the disclosure, are intended to cover a non-exclusive inclusion, such that a device, system, assembly that comprises a list of components does not include only those components but may include other components not expressly listed or inherent to such system, or assembly, or device. In other words, one or more elements in a system or device proceeded by “comprises… a” does not, without more constraints, preclude the existence of other elements or additional elements in the system or device.
[0049] The present subject matter relates to a double cone coal crusher to enhance maceral liberation of coal particles to improve coking potential of coal.
[0050] It should be noted that the description and figures merely illustrate the principles of the present subject matter. It should be appreciated by those skilled in the art that conception and specific embodiment disclosed may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present subject matter. It should also be appreciated by those skilled in the art that by devising various arrangements that, although not explicitly described or shown herein, embody the principles of the present subject matter. Furthermore, all examples recited herein are principally intended expressly to be for pedagogical purposes to aid the reader in understanding the principles of the present subject matter and the concepts contributed by the inventor(s) to furthering the art, and are to be construed as being without limitation to such specifically recited examples and conditions. The novel features which are believed to be characteristic of the present subject matter, both as to its organization and 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.
[0051] These and other advantages of the present subject matter would be described in greater detail with reference to the following figures. It should be noted that the description merely illustrates the principles of the present subject matter. It will thus be appreciated that those skilled in the art will be able to devise various arrangements that, although not explicitly described herein, embody the principles of the present subject matter and are included within its scope.
[0052] Figure 1a and 1b illustrates front view and side view of the double cone coal crusher 100. The double cone coal crusher 100 includes a crushing unit (not shown in figure), gear box assembly 101, motor 102, transmission belt cover by a cover 103, product collection hopper 104, product discharge chute 105. Further, the double cone coal crusher 100 is covered by a sheet metal cover 106. Referring to Fig. 2 illustrating cross sectional view of a double cone coal crusher 100 according to one of the embodiment of present subject matter. The present double cone coal crusher 100 comprises a crushing unit having two coaxial cones namely an inner cone 201 and an outer cone 202, having different cone angles. The cone angles are selected in a way to form the gap between the two cones 201, 202 which is defining the crushing zone. The inner cone 201 is placed coaxially inside the outer cone 202, with a crushing space provided between both of the inner cone 201 and the outer cone 202. The inner cone 201 is mounted on a bottom cone screw 203 with matching threads to adjust the height of the inner cone 201. The bottom cone screw 203 is used to adjust the gap between the inner cone 201 and the outer cone 202 to obtain desired product size distribution. The outer cone 202 having greater cone angle than the inner cone 201, is in the shape of a frustum having a bearing on both the top end and the bottom end. In the crushing unit, the outer cone 202 is powered cone means rotatable cone and the inner cone 201 is a stationary cone.
[0053] The inner cone 201 can be rotated to slides through threads of the screw for lifting or lowering of the inner cone 201. The purpose of the above arrangement is to adjust the gap between the inner cone 201 and the outer cone 202 to obtain desired product size distribution. The top bearing of the outer cone 202 is equipped with a timer pulley arrangement which is powered by a geared motor 102 with a variable frequency drive. The motor 102 is mounted on the exterior frame with shaft parallel to the cone shaft and transmitting power by a timer belt for better transmission efficiency. The machine can also be modified to be powered with a gear arrangement from the bottom portion of the cone. This arrangement shall be provided in the event of higher size machine or for higher capacities.
[0054] In the present crushing unit, the inner cone 201 comprises a plurality of outer shear pads 301 on the outer surface and the outer cone 202 comprises a plurality of inner shear pads 701 on the inner surface.
[0055] Referring to Fig. 3a and 3b illustrating the inner cone without shear pads and with shear pads respectively, according to one of the embodiment. The outer surface of the inner cone 201 have a plurality of fixture holes 302 and the outer shear pads 301 have fixtures holes 504. The outer shear pads 301 are mounted through bolts on the outer surface of the inner cone 201 through a plurality of screws or bolts engaging with the inline fixture holes 302, 504. The inner cone 201 is vertically layered into rows 303 of different radius and staggered along the circumference. The outer shear pads 301 are machined out from a blocks of metal, having radius corresponding to these rows 303. A specialized metal which can resist the aberration caused by the coal is used as the block metal for machining the outer shear pads 301. All the shear pads 301 are mounted different in the geometric aspect to fit the curvature of the inner cone 201.
[0056] Referring to Fig. 5 illustrating outer shear pads. The outer shear pads 301 have a cutting surface 501 and a mounting surface 502. The outer shear pads 301 are mounted on the outer surface of the inner cone 201 from the mounting surface 502 side. The mounting surface 502 is a smooth surface which is machined to gain the convexity of the outer surface of the inner cone 201. The cutting surface 502 is provided with a groove pattern forming cutting edges 503, which are specifically designed to obtain defined gap in the crushing space as well as providing the specialized force field for the coal particle crushing. After forming cutting edges 503 on the outer shear pads 301, the cutting surface 501 forms serrated configuration. These outer shear pads 301 having serrated configuration, of different sizes are mounted on the outer surface of the inner cone 201 in a staggered manner. The staggered arrangement of the outer shear pads 301 is such that no two cutting edges 503 are aligning in vertical direction with each other. This staggered arrangement of the outer shear pads 301 thus provides more effective numbers of cutting edges 503 for coal particle crushing during the material flow.
[0057] Design of the outer shear pads 301 depends on the characteristics of crushing material and desired product required after crushing. Other embodiments of the outer shear pads 301 are possible, but the core concept of providing such pads 301 on the inner cone 201 is same.
[0058] Referring to Fig. 6 illustrating the outer cone 202 exterior and cut section view without cone pad assembly. The inner surface of the outer cone 202 have fixture holes 602 and the inner shear pads 701 have fixtures holes 705. The inner shear pads 701 are mounted through bolts on inner surface of the outer cone 202 through these fixture holes 602, 705 via a fastener means such as screw of bolt. The outer cone 202 is vertically divided into rows of different radius and staggered along the circumference. The inner shear pads 701 are machined out from blocks of metal with radius corresponding to these rows. A specialized metal which can resist the aberration caused by the coal is used as the block metal for machining the inner shear pads 701.
[0059] Referring to Fig. 7 illustrating inner shear pads 701. The inner shear pads 701 have a cutting surface 702 and a mounting surface 703. The mounting surface 703 is mounted on the inner surface of the outer cone 202. The mounting surface 703 is a smooth surface which is machined to gain the concavity of the inner surface of the outer cone 202. The cutting surface 702 is provided with a groove pattern forming cutting edges 704, which are specifically designed to obtain defined gap in the crushing space as well as providing the specialized force field for the coal particle crushing. These inner shear pads 701 of different sizes are mounted on the inner surface of the outer cone 202 in a staggered manner. The staggered arrangement of the inner shear pads is such that no two cutting edges 704 are aligning in vertical direction. This staggered arrangement of the inner shear pads 701 thus provides more effective numbers of cutting edges 704 for coal particle crushing during the material flow.
[0060] Design of the inner shear pads 704 depends on the characteristics of crushing material and desired product required after crushing. Other embodiments of the inner shear pads 701 are possible, but the core concept of providing such pads 701 on the outer cone 202 is same.
[0061] Referring to figure 6, the bearing 601 on top end of the outer cone 202 is connected to drive unit via. a transmission belt 103. Referring back to figure 1, the drive unit includes a gear box assembly 101 with its input shaft driven by the motor 102 and output shaft connected to the transmission belt 103. The motor 102 is mounted on the exterior frame with shaft of the motor 102 parallel to shaft of the inner cone 201 and outer cone 202. According to another embodiments of the present double cone coal crusher 100, the outer cone top bearing 601 is equipped with timer pulley arrangement which is powered by a geared motor with a variable frequency drive. The geared motor is mounted on the exterior frame with shaft of the motor parallel to shaft of the inner cone 201 and the outer cone 202.
[0062] According to another embodiment the crushing unit can be driven by a gear arrangement from the bottom portion of the cones. This embodiment has advantages in the event of higher size crusher or for crushers of higher capacities.
[0063] Again referring to Fig. 2 feeding of coal in crushing space between the outer cone 202 and the inner cone 201 is done through a feed hopper 204. A standard vibratory feeder or a bucket elevator can be used as feed hopper 204. Further, a product collection unit is positioned below the crushing unit. The product collection unit includes a product collection hopper 104, a discharge chute 105 and a plurality of scrapper blades 205 to move the enhanced maceral liberated crushed coal out from the discharge chute 105.
[0064] The coal is fed from the feed hopper 204 in the crushing space between the inner cone 201 and the outer cone 202. The inner shear pad 701 on the outer cone 202 and outer shear pad 301 on the inner cone 201 applies a shear force on to the coal. The coal breaks in accordance with these three conditions -
a) By getting arrested between the grooves of both the inner shear pad 701 and outer shear pads 301
b) By getting arrested between the groove of cutting surface of one and inclined surface of the other shear pads.
c) By getting arrested between smooth surfaces of the inner shear pads 701 and outer shear pads 301.
[0065] When the particle is subjected to condition (a) the fracture will be along the tangential planes and resulting in the coarse breakage of the particle. Due to the application of the bodily shear force as described, the vitrinite gets elongated until fracture point, by this time the breakage of the inertinites is already completed as they are most friable maceral. Resulting particles have elongated grains of exposed vitrinite along with the small inertinite portions.
[0066] When the particle is subjected to condition (b) the fracture of the particle will be caused by a joint action of shear forces on the body and on the surface on the particle. The resultant particle will have less number of elongated grains as compared to case (a) but good balance of the particle size distribution as fines will be generated due to the surficial shear forces.
[0067] When the particle is subjected to case (c) condition the fracture will be mostly from the periphery of the particle, this breaks the parent particle from the surface while inducing shear strain on to the large particle.
[0068] A particle goes through different combinations of case a, case b and case c, resulting in a product which is primarily broken in shear mode. The product is collected in the collection hopper 104 then to discharge chute 105. The scraper blades 205 move the material out of the discharge chute 105 and is collected for further processing.
[0069] The entire assembly is covered with the help of steel panels or side covers 106 to limit the dust extraction and to have additional safety against the rotating members.
[0070] The presented double cone coal crusher 100 can process coal not only for the particle granulometry but enhanced liberation of macerals. Presented double cone coal crusher 100 can apply forces on the tangential parallel planes of the particles. The shear force applied onto the particle are of two types; tangential or surficial shear and bodily shear force.
[0071] Presented double cone coal crusher produce the coal particles in the desired range for coke making applications. The machined curved inner shear pads 701 and outer shear pads 301 are designed to provide cutting edges 503, 704 which are helpful in providing the offset shear forces which can enhance liberation of the particles and subsequently increase the coking potential of the coal.
[0072] Due to the enhanced liberation of the particles, inferior grade coals can be effectively utilized in the coke making application. The introduction of the inferior grade coal in the coal blend can reduce the coke cost.
[0073] 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.”
[0074] It will be further appreciated that functions or structures of a plurality of components or steps may be combined into a single component or step, or the functions or structures of one-step or component may be split among plural steps or components. The present invention contemplates all of these combinations. Unless stated otherwise, dimensions and geometries of the various structures depicted herein are not intended to be restrictive of the invention, and other dimensions or geometries are possible. In addition, while a feature of the present invention may have been described in the context of only one of the illustrated embodiments, such feature may be combined with one or more other features of other embodiments, for any given application. It will also be appreciated from the above that the fabrication of the unique structures herein and the operation thereof also constitute methods in accordance with the present invention. The present invention also encompasses intermediate and end products resulting from the practice of the methods herein. The use of “comprising” or “including” also contemplates embodiments that “consist essentially of” or “consist of” the recited feature.
[0075] Although embodiments for the present subject matter have been described in language specific to structural features, it is to be understood that the present subject matter is not necessarily limited to the specific features described. Rather, the specific features and methods are disclosed as embodiments for the present subject matter. Numerous modifications and adaptations of the system/component of the present invention will be apparent to those skilled in the art, and thus it is intended by the appended claims to cover all such modifications and adaptations which fall within the scope of the present subject matter.

We claim:

1. A double cone coal crusher (100) to enhance maceral liberation in coal to improve coking, the double cone coal crusher (100) comprises:
a feed hopper (204) to feed coal in the cone type coal crusher (100);
a crushing unit positioned below the feed hopper (204);
a drive unit to drive the crushing unit, the drive unit comprising a gear box assembly (101) having input end driven by a motor (102) and output end connected to a transmission belt (103); and
a product collection unit positioned below the crushing unit comprising a product collection hopper (104), a discharge chute (105) and a plurality of scrapper blades (205) to move the enhance maceral liberated crushed coal out from the discharge chute (105);
characterized in that
the crushing unit comprises:
an inner cone (201) having bottom end mounted on a bottom cone screw (203) with matching threads to adjust the height of the inner cone (201), wherein a plurality of outer shear pads (301) are provided on the outer surface of the inner cone (201);
an outer cone (202) placed coaxially outside the inner cone (201) having bearing on bottom and top end, wherein top end bearing (601) is in connection with the transmission belt (103) which provide the outer cone (202) rotating motion and wherein a plurality of inner shear pads (701) are provided on inner surface of the outer cone (202).
2. The double cone coal crusher (100) as claimed in claim 1, wherein the inner cone (201) has fixtures holes (303) on the outer surface to accommodate the plurality of inner shear pads (301).
3. The double cone coal crusher (100) as claimed in claim 1, wherein each shear pad of the plurality of outer shear pads (301) is machined out from metal blocks, with different radius, to cover rows (303) of differential curvature on the outer surface of the inner cone (202).
4. The double cone coal crusher as claimed in claim 1, wherein the mounting surface (502) of the plurality of outer shear pads (301) are plain and machined to gain the convexity to match the surface of inner cone (201) and cutting surface (501) has a plurality of grooves forming cutting edges (503) giving serrated configuration to cutting surface (501), to obtain defined gap in the crushing space.
5. The double cone coal crusher (100) as claimed in claim 1, wherein the plurality of outer shear pads (301) are arranged on the inner cone (201) in a circumferential staggered manner to avoid vertical alignment of edges of corresponding outer shear pads (301).
6. The double cone coal crusher as claimed in claim 1, wherein the outer cone 202 has fixtures holes (602) on the inner surface to accommodate the plurality of inner shear pads (701).
7. The double cone coal crusher (100) as claimed in claim 1, wherein each shear pad of the plurality of inner shear pads (701) is machined out from a metal blocks with different radius, to cover differential curvature of the inner surface of the outer cone (202).
8. The double cone coal crusher (100) as claimed in claim 1, wherein the metal of the metal blocks is a specialized metal which can resist the aberration caused by the coal.
9. The double cone coal crusher (100) as claimed in claim 1, wherein the mounting surface (703) of the plurality of inner shear pads (701) are plain and machined to gain the concavity to match the surface of outer cone (202) and cutting surface (702) has a plurality of grooves forming cutting edges (704), to obtain defined gap in the crushing space.
10. The double cone coal crusher (100) as claimed in claim 1, wherein the plurality of inner shear pads (701) are arranged on the outer cone (202) in a circumferential staggered manner to avoid vertical alignment of edges of corresponding inner shear pads (701).