PROCESS AND SYSTEM FOR MANUFACTURING A SOLID AGGLOMERATE

Abstract

The present invention relates to systems and processes for manufacturing solid agglomerates. In this scenario, the present invention provides a process for manufacturing a solid agglomerate (5), by means of a roller press (10) comprising two rollers (10a, 10b) provided with cavities (11) fillable with granulated compositions, the process comprising the steps of (i) supplying, from above, a first composition in a first upper angular portion (12a) of each of the rollers (10a, 10b) of the roller press (10); (ii) supply, from above, a second composition on a second upper angular portion (12b) of each of the rollers (10a, 10b) of the roller press (10), where, for the same roller (10a, 10b), the second upper angular portion (12b) is located downstream of the first upper angular portion (12a) with reference to the direction of rotation of each roller (10a, 10b); and (iii) pressing the material supplied on the rollers (10a, 10b) so as to form a solid agglomerate (5) comprising a core (5n) formed by the second composition and a cladding (5r) formed by the first composition. The present invention also provides a system associated with the method described above.

Claims

1. The process for manufacturing a solid agglomerate, by means of a roller press comprising two rollers fitted with cavities fillable with granulated compositions, characterized in that it comprises the steps of: providing, from above, through a first means for providing the first composition, a first composition on a first upper angled portion of each of the rollers of the roller press; providing, from above, through a second means for providing the second composition, a second composition in a second upper angled portion of each of the rollers of the roller press, wherein, for the same roller, the second composition received in the second upper angular portion is located downstream of the first upper angular portion that receives the first composition, with reference to the direction of rotation of each roller; and pressing the material supplied onto the rollers to form a solid agglomerate comprising a core formed by the second composition and a cladding formed by the first composition.

2. Process according to claim 1, characterized in that the step of providing a first composition in a first upper angular portion is carried out simultaneously and separately for each roll.

3. Process according to claim 1, characterized in that the step of providing a second composition in a second upper angular portion is carried out in the same place for both rollers.

4. Process according to claim 3, characterized in that the step of providing a second composition in a second upper angular portion is carried out between the rollers.

5. Process according to claim 1, characterized in that it further comprises the step of pre-compacting the second composition prior to the step of supplying a second composition into a second upper angular portion of each of the rollers of the roller press.

6. System for manufacturing a solid agglomerate, comprising a roller press having two rollers provided with cavities fillable with granulated compositions, the system characterized in that it comprises: first means for providing, from above, a first composition on a first upper angled portion of each of the rollers of the roller press; second means for supplying, from above, a second composition on a second upper angled portion of each of the rollers of the roller press, wherein the means are positioned so that, for the same roller, the second composition received in the second upper angular portion is located downstream of the first upper angular portion that receives the first composition, with reference to the direction of rotation of each roller; and means for pressing the material supplied onto the rollers to form a solid agglomerate comprising a core formed by the second composition and a cladding formed by the first composition.

7. System according to claim 6, characterized in that the means for providing a first composition in a first upper angular portion are at least one of: at least one side silo adapted to store the first composition; at least one side dosing screw of the first composition; and at least one passage silo adapted to direct the first composition over the first upper angular portion of each of the rollers of the roller press.

8. System according to claim 6, characterized in that the means for providing a second composition in a second upper angular portion are at least one of: at least one central silo adapted to store the second composition; and at least one central dosing screw of the second composition driven by a motor.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The detailed description below refers to the attached figures and their respective reference numbers.

[0017] FIG. 1 illustrates a schematic sectional view of a roller press system according to the state of the art.

[0018] FIG. 2 illustrates a schematic sectional view of a preferred embodiment of the system of the present invention.

[0019] FIG. 3 illustrates a schematic view of the roller press according to a preferred embodiment of the system of the present invention.

[0020] FIG. 4 illustrates a schematic view of a solid agglomerate manufactured using the process and system of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

[0021] Preliminarily, it should be noted that the following description is based on a preferred embodiment of the invention. As will be evident to anyone skilled in the art, however, the invention is not limited to this particular embodiment.

[0022] The present invention provides a system for manufacturing a solid agglomerate 5, comprising a roller press 10 which has two rollers 10a, 10b rotating in opposite directions and provided with cavities 11 fillable with granulated compositions, as illustrated in FIG. 1. Said technique, which is already known from the state of the art, comprises a central feeder provided with a dosing screw 42 for feeding a granulated composition between rollers 10a, 10b for pressing and forming the solid agglomerates 5.

[0023] In the present invention, unlike the technique in FIG. 1, two different compositions are supplied to the rollers 10a, 10b at different locations so as to form a solid agglomerate 5 comprising a core formed by one composition and a cladding formed by another composition.

[0024] With reference to FIGS. 2 and 3, which illustrate a preferred embodiment of the system of the present invention, means are provided for supplying, from above, a first composition into a first upper angled portion 12a of each of the rollers 10a, 10b of the roller press 10. The supply of the first composition is indicated in FIGS. 2 and 3 by green arrows.

[0025] The means for supplying the first composition onto a first upper angular portion 12a of each of the rollers 10a, 10b of the roller press 10 may comprise, for example, (i) at least one side silo 30 adapted to store the first composition, (ii) at least one side dosing screw 32 of the first composition and/or (iii) at least one passage silo 34 adapted to direct the first composition onto the first upper angular portion 12a of each of the rollers 10a, 10b of the roller press 10.

[0026] Additionally, the present invention will further comprise means for providing, from above, a second composition on a second upper angled portion 12b of each of the rollers 10a, 10b of the roller press 10. The supply of the second composition is indicated in FIGS. 2 and 3 by red arrows.

[0027] The means for supplying the second composition to a second upper angular portion 12b of each of the rollers 10a, 10b of the roller press 10 can include, for example, (i) at least one central silo 40, which stores the second composition (ii) at least one central dosing screw 42 of the second composition driven by a motor 44. Preferably, the central dosing screw 42 also pre-compacts the second composition prior to the step of supplying it to the roller press 10.

[0028] It is defined in this description that the first 12a and second upper angular portions 12b of each roller 10a, 10b correspond to the complementary upper angles of the cylinders (rollers), which together add up to 180. In FIG. 3, the first upper angular portion 12a is represented on each roller by the green quarter circle, while the second upper angular portion 12b is represented on each roller by the red quarter circle.

[0029] Although each of the angular portions is represented in FIG. 3 by an opening angle of 90 (a quarter of a circle), these portions are not limited to this specific angle and can vary according to need. The important thing is to ensure that for the same roller 10a, 10b, the second upper angular portion 12b is located downstream of the first upper angular portion 12a with reference to the direction of rotation of each roller 10a, 10b.

[0030] Thus, for a given solid agglomerate manufactured by the system of the present invention, its cladding material (first composition) will first be deposited on the rollers in the first upper angular portion 12a. This material will partially or completely fill the cavities 11 of the rollers 10a, 10b. Then, in the second upper angular portion 12b, close to the point of least distance between rollers 10a, 10b, which is where the pressing takes place, the core material of the solid agglomerate (second composition) is supplied onto rollers 10a, 10b. Thus, when pressing takes place, an agglomerate 5 will be formed comprising the first composition in its 5r cladding and the second composition in its 5n core, as shown in FIG. 4.

[0031] The ratio between the amount of material in the core and in the cladding of the solid agglomerate 5 will be regulated by the feed rate of each material in the press 10. By increasing, for example, the feed rate of the second composition and leaving the first unchanged, a solid agglomerate with a larger and/or denser core is achieved.

[0032] The present invention further provides a process for manufacturing a solid agglomerate 5, by means of a roller press 10 comprising two rollers 10a, 10b provided with cavities 11 fillable with granulated compositions, the process comprising the steps of: [0033] a) providing, from above, a first composition on a first upper angular portion 12a of each of the rollers 10a, 10b of the roller press 10; [0034] b) providing, from above, a second composition on a second upper angular portion 12b of each of the rollers 10a, 10b of the roller press 10, whereby, for the same roller 10a, 10b, the second upper angular portion 12b is located downstream of the first upper angular portion 12a with reference to the direction of rotation of each roller 10a, 10b; and [0035] c) pressing the material supplied onto rollers 10a, 10b to form a solid agglomerate 5 comprising a core 5n formed by the second composition and a cladding 5r formed by the first composition.

[0036] Preferably, the step of providing a first composition on a first upper angular portion 12a is carried out simultaneously and separately for each roll 10a, 10b, as shown in FIGS. 2 and 3.

[0037] Preferably, the step of providing a second composition on a second upper angled portion 12b is carried out at the same location for both rollers 10a, 10b. More preferably, this step is carried out between the rollers 10a, 10b.

[0038] Preferably, the process of the present invention additionally comprises the step of pre-compacting the second composition prior to the step of supplying a second composition into a second upper angled portion 12b of each of the rollers 10a, 10b of the roller press 10. As already mentioned, this step is preferably carried out by the central dosing screw 42.

[0039] The solid agglomerate 5 formed by the process and system described above is illustrated in FIG. 4 and comprises a core 5n formed by the second composition and a cladding 5r formed by the first composition. The solid agglomerate 5 of the present invention may be, for example, a combustible coal briquette or a metallic agglomerate, such as a pellet or a ferrous briquette.

[0040] In the case of fuel briquettes, preferably the second composition, which forms the 5n core, comprises at least one coking coal and at least one binder. The core material 5n, therefore, is the coking material commonly used in fuel briquettes. More preferably, the second composition, which forms the 5n core, comprises 60 to 70% by mass of coking coal and 6 to 10% by mass of binder.

[0041] Preferably, the first composition, which forms the 5r cladding, comprises a non-coking coal, or residue thereof, and at least one binder. The coal in the cladding composition 5r can be, for example, coke grindings or coal waste in general, low quality coals, etc. It is worth noting here that any inert coal waste (non-coking) can be used in the composition of the 5r cladding. In this way, when heated inside the reduction furnace, the 5r cladding material will not coke, which prevents the surfaces of the agglomerates from sticking together and, consequently, the formation of curls.

[0042] Most preferably, the first composition, which forms the 5r cladding, comprises 70 to 95% by mass of non-coking coal, coke grindings, coal waste or any combination thereof, and 5 to 15% by mass of binder.

[0043] In a second embodiment of the present invention, the solid agglomerate 5 is a metallic agglomerate, such as a ferrous pellet or briquette. In this case, an inert material, preferably metallic, is used in the cladding 5r of the agglomerate to serve as a sacrificial material. The core 5n would be formed by the material of interest.

[0044] The solid chipboard 5 of the present invention can be manufactured in any existing geometric shape, so that the scope of protection of the present invention is not limited to the oval shape represented in FIG. 4.

[0045] Thus, as explained above, the present invention provides a system and a process for manufacturing a solid agglomerate so that it comprises more than one distinct composition in its structure, where each composition would be located in a certain region of it (cladding and core).

[0046] Numerous variations affecting the scope of protection of the present application are permitted. This reinforces the fact that the present invention is not limited to the particular configurations/concretizations described above.