DEVICE FOR MAKING A MULTI-COMPONENTS PRODUCT MATERIAL
20190076798 · 2019-03-14
Inventors
Cpc classification
B01F27/84
PERFORMING OPERATIONS; TRANSPORTING
B01F23/711
PERFORMING OPERATIONS; TRANSPORTING
B01F35/752
PERFORMING OPERATIONS; TRANSPORTING
B01F27/85
PERFORMING OPERATIONS; TRANSPORTING
B01F23/57
PERFORMING OPERATIONS; TRANSPORTING
B01F27/706
PERFORMING OPERATIONS; TRANSPORTING
B01F35/751
PERFORMING OPERATIONS; TRANSPORTING
B01F27/703
PERFORMING OPERATIONS; TRANSPORTING
Y02E60/10
GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
B01F27/0724
PERFORMING OPERATIONS; TRANSPORTING
B01F23/511
PERFORMING OPERATIONS; TRANSPORTING
B01F35/91
PERFORMING OPERATIONS; TRANSPORTING
B01F35/715
PERFORMING OPERATIONS; TRANSPORTING
International classification
Abstract
A device for making of a multi-components product material. The device includes a processing and homogenizing chamber for primary particle components. The chamber includes at least two sets of rotary shovels, which rotate in parallel in a mutually counter-rotating, homogenizing mode, inlet(s) into the chamber for at least one secondary component in a fluid state and/or fine particulate material state, which interacts with the primary components while they are moved around in the chamber by sets of the shovels, and an outlet in the chamber to allow the primary and secondary components to leave the chamber as the multi-component product material.
Claims
1. A device for making of a multi-components product material, comprising: a processing chamber with at least one supply inlet for primary particle components, said chamber configured to homogenize the primary components; at least two sets of rotary shovels, each set with a plurality of rotary shovels on a common rotary shaft in order to homogenize the primary components in the chamber, the rotary shafts of the at least two sets of rotary shovels being caused to rotate in parallel in a mutually counter-rotating, homogenizing mode; inlet(s) into the chamber for at least one secondary component in a fluid state and/or fine particulate material state, e.g. powder, and which is to interact with said primary components in the chamber while the primary components are moved about in the processing chamber by sets of the rotary shovels, and an outlet in a bottom region of the processing chamber to allow the primary and secondary components to be discharged from the chamber as the multi-component product material, wherein at least one heating agent inlet into the processing chamber is provided to let a heating agent enter the processing chamber to heat at least partly primary components therein and to dry off any unwanted liquid moisture from the primary components, wherein the device is configured to process primary particle components and fine particulate materials which are made from coke, and configured to process secondary component in fluid state which is pitch, and wherein the bottom region outlet is directly upstream of a product finalizing stage being a pressure operated mould to yield a final product of said multi-component product material being an electrode.
2. The device of claim 1, wherein the heating agent is superheated steam or inert gas.
3. The device of claim 1, wherein the chamber inlets for the secondary component(s) provide for delivery of said secondary component(s) as a sprayed liquid.
4. The device of claim 1, wherein the processing chamber and the at least two sets of rotary shovels are configured to process the primary components which are a mixture of differently sized particles.
5. The device of claim 1, wherein multiple inlets into the processing chamber are provided to enable multiple second components to be delivered in succession to the processing chamber to yield multiple layers of second components on the primary components.
6. The device of claim 1, wherein a heating agent composition status and property sensor is located upstream of the at least one heating agent inlet to the processing chamber.
7. The device of claim 6, wherein a supply of heating agent restoring fluid is connectable to the processing chamber if the heating agent requires restoration to its nominal properties.
8. The device of claim 1, wherein the shovels of each set of shovels extend radially from a respective surface of a common rotary shaft, wherein each shovel, as viewed radially from the rotary shaft, has a curved cross-section so as to present upon rotation of the set of shovels a convex surface to face the primary component(s) to be homogenized, wherein the shovel at an radially outer region is forwardly flared in a direction of a homogenizing mode of rotation, the outer region thereby having a forward face forming an angle with the rotary forwardly facing convex surface of the remainder of the shovel, wherein an aerodynamic member extends rearwards from a concave side of the shovel, transversely of a radial direction of the shovel, wherein the aerodynamic member has its widest dimension closest to said concave side, and wherein a space between said concave side of the shovel and the aerodynamic member yields a sealed cavity.
9. The device of claim 1, wherein a radially extending side edge region of at least some of the shovels is provided with a wing-like side member protruding laterally from said side edge region, and wherein the wing-like side member is turned forwardly in the direction of rotation of the shovel in its homogenizing operational mode, so as to form an angle with an edge of a convex side of the shovel and a forwardly flared region of the shovel.
10. The device of claim 7, wherein the heating agent restoring fluid is one of inert gas, vapour, superheated steam and air.
11. The device of claim 8, wherein the aerodynamic member has a drop or wedge shaped configuration.
12. The device of claim 8, wherein a radially extending side edge region of at least some of the shovels is provided with a wing-like side member protruding laterally from said side region, and wherein the wing-like side member is turned forwardly in the direction of rotation of the shovel in its homogenizing operational mode, so as to form an angle with an edge of the convex surface side of the shovel and the forwardly flared region of the shovel.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
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DETAILED DESCRIPTION OF THE INVENTION
[0062] In its simplest form, the present device is as shown on
[0063] In this first mode of operation containers 1, 2, 3 with primary components 4, 5, 6 of different size, respectively, are heated to provide that the petroleum coke, which comprises each of the primary components, has a correct temperature when at least one secondary component, in the example pitch 7, in heated liquid state from a tank 8 is delivered via line 9 into a chamber 10 of a homogenizer 10. It is possible to consider that more than one secondary component may need to be delivered, in which case further container(s) 8 may be provided to supply its/their contents 7 via line 9 into said chamber 10. The pitch may in some cases contain particulate material, e.g. in powder form, or if more than one secondary component is supplied, one may e.g. be pitch and the other particulate material, as will be further described.
[0064] This way of operation is in order to obtain optimal coverage by pitch on the coke and to save time and wear in use of the final product, i.e. the electrode. However, in a production line of asphalt, the use of such pre-heating of containers is well known.
[0065] If the containers heat the coke particles/components to a correct temperature and the blender or homogenizer 10 is without any required heating inside the chamber 10, but only takes care of the addition of pitch onto the coke particles, this is the simplest approach of making the mass material.
[0066] Pitch 7 is in a conventional manner added from the pre-heated tank 8 and the proper amount is delivered to the chamber 10 via line 9 according to weight of the pitch as defined in a production prescription. Additional secondary component(s) 7 may be supplied to the chamber 10, if required, via line 9.
[0067] The homogenizer 10 blends the secondary component(s) 7; 7, e.g. pitch and/or particulate material, and the composition of coke particles 4; 5; 6 according to size to obtain an optimal homogeneous mass material 10 which is well suited for repetitive manufacturing of electrodes.
[0068] When the electrode mass material 10 is completely made, then it is fed from the homogenizer 10 to a moulding apparatus 11 where it is compacted by applied pressure to yield the final product, i.e. the electrode 12.
[0069] With reference to e.g.
[0070] A modification of the sets 13; 14 of shovels on
[0071] It will be readily appreciated by an average expert in the art that more than two sets of shovels could be contemplated, as e.g. indicated on
[0072] Further, although in the example three primary components are indicated, a less or a greater number of component of could be used, as required. Thus, the example is in no way meant to limit the scope of the present invention.
[0073] Each shovel, on
[0074] The shafts 25; 26 have one respective end 25; 26 linked to drive motors 27; 28 and gear boxes 27; 28, see
[0075] The directions of rotation of the at least two sets 13; 14 of shovels could be mutually reversed upon a phase of operation causing the product material 10 to leave the chamber 10, thereby yielding a second mutually counter-rotating mode, i.e. a mode of rotation opposite to that shown on
[0076] In order to enhance homogenization properties for certain types of primary components, such as e.g. petroleum coke, to be processed, an aerodynamic member 33 is provided, the member 33 e.g. having a drop shaped or wedge shaped configuration and extending rearwards from a concave side 34 of the shovel, thus essentially preventing the concave surface from being visible. The aerodynamic member 33 has its widest dimension closest to said concave surface 34. The aerodynamic member 33 prevents build-up of particlecakes and is useful also in a situation with a product mixture having non-consistent composition. The top 33and bottom 33 of the member 33 will be closed, as indicated by the elements 35; 36 so that the member 33 with the associated elements 35; 36 in co-operation with the concave side 34 of the shovel constitutes a closed cavity. The aerodynamic member may be of a slightly flexible type such as e.g. of a material known as Viton or may have a non-stick coating such as e.g. Teflon. It could be made of a rigid material if e.g. provided with as non-stick coating.
[0077] Such aerodynamic member 33 may be particularly suitable for use in the case that the components which are to be processed, i.e. to be dried and/or heated, as well as to be homogenized, include fractions of fine particulate materials, and/or being combined with addition of liquids from low to high viscosity.
[0078] The issue of a build-up of finely divided particulate material on the rear side (concave side) 34 of a shovel is indeed of concern when processing some specific types of material. The problem is that when such build-up of material detaches from a shovel, it will be in the form of large lumps. This must be avoided when processing e.g. finely divided particulate material or powder type of material having air inducing powders and powders having properties of static electricity build-up or formation of crystalline bonding.
[0079] Further, in the present context, homogenizing primary components like petroleum coke of different sizes is a challenge, and it is important not to have shovels with an open concave rear side at which build-up of sticky coke particles as well as pitch could occur, thereby creating operational problems. Thus, with the use of an aerodynamic member 33 as generally described, there will no longer be present a visible concave region on rear side of the shovel for build-up of such problematic material to be processed.
[0080] As shown on
[0081] This yields a most suitable sub-dividing of the shovels from a manufacturing point of view with shovels on each side of the square profile. In the examples shown, one side may have two shovels and the other sides just one shovel. However, this is not to be construed as a limitation of the embodiment, as there may be more shovels on either side, dependent on the axial length of the shafts 25, 26. Shovels can also be mounted diagonally, with 180 in between in each longitudinal segment, or even by every 90 for certain processes.
[0082] In order to obtain with the at least one rotary set of shovels enhanced properties, as regards lifting capability on the particulate primary components which are to be homogenized, possibly be heated and/or dried or otherwise processed, both radially and tangentially, as well as obtaining an increased arc length in axial direction, the shovel 29 having the features of as just described could be further improved.
[0083] As mentioned above, the shovel 29 has a convex side 30 and the rear of the side thereby forming a concave side 34, the concave side however being covered by said aerodynamic member 33. The improvement involves a wing-like side member 37 at a radially extending side edge of the convex side 30. The member 37 has a radially extending part 37 and a forwarded flared part 37 at a radially outer region thereof. In an embodiment of the invention, these two parts 37, 37 are suitably turned forwardly in the direction of rotation to form an angle with said convex side 30. The member 37 contributes to the enhanced properties as mentioned above. It will be appreciated that the shovels located on a rotary shaft 25; 26, as shown on
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[0085] Although only two sets 13; 14 of shovels are shown on
[0086] Using a square cross-section for the shafts 25; 26 it becomes very simple to position the respective shovels on the shafts with proper and preferred angular orientation or twisting relative to an axial direction of the shaft or the rectilinear sides of the shaft. A shaft with a square cross-section has also an inherent high stiffness or rigidity against twisting about and bending relative to its longitudinal axis. Although the shafts 25; 26 may have, as seen from their outside, a square cross-section, a shaft with a circular cross-section could be mounted inside the shaft of square cross-section and be fixedly attached thereto by welding, gluing, bolts or screws and be supported at one end 25; 26 by roller bearings 38; 39 at one end and letting the other end 25; 26 engage the respective gear boxes 27; 28 which are operated by respective motors 27; 28.
[0087] The shafts of circular cross-section when passing through the walls of the chamber 10 are sealed against fluid leakage to the outside by means of a packing material (not shown) riding on the circumference of the shafts thereat.
[0088] It is clearly seen from e.g.
[0089] As indicated on
[0090] In a second and alternative mode of operation, see
[0091] Some component(s) to be processed in the chamber 10 may be inflammable or cause the atmosphere in the chamber 10 to be inflammable, and in such a case the heating agent should be of a nature which prevents any fire in the chamber 10 or its vicinity, thereby avoiding a risk of an explosion.
[0092] It may in a particular application, e.g. when making an electrode product material 10, be of advantage to pre-heat at least one of the primary components before all of the primary components are heated, and dried, if required, in the chamber 10. In this process, the fan 47 will operate to provide a required circulation volume per time unit of the heating agent.
[0093] The loop includes a filter unit 46 at a heating agent exit end 51 of the homogenizer chamber 10, a fan 47 downstream thereof, and a heater 48 downstream thereof for the heating agent and upstream of heating agent inlet(s) 48 to the chamber 10. In addition, there is present a tank 49 of pressurized fluid, such as e.g. nitrogen, to shoot such fluid via filter unit inlets 50 into filter bags 46 of the filter unit 46 in order that the filter unit 46 retains its ability to filter petroleum coke dust. The filter unit outlet 51 serving also as the heater agent exit end from the chamber 10 may be located at the same location as the inlets 50, if possible.
[0094] In addition, there is an evacuation line 52, suitably associated with the heater 48 to evacuate the shooting fluid and the small amount of air which inherently is present in the supplied petroleum coke. The evacuated fluid may either be recycled or ventilated into the open air, i.e. the environment, via line 52.
[0095] When the petroleum coke has the right temperature, then heated pitch 7 is supplied into the homogenizing chamber 10 via line 9 to mix with the coke 4, 5, 6, yielding that the product material 10 exiting the chamber 10 has an optimal homogenous property when supplied to the mould 11 in which the electrode 12 is made.
[0096] As indicated above, the homogenizer is associated with a heating agent supply, suitably in the form of dry, superheated steam or inert gas, e.g. nitrogen, in a closed loop configuration, suitably delivered from a supply 53. A sensor 54 is suitably located at a branch-off from the loop, e.g. at the outlet of the fan 47. The sensor is capable of sensing the properties of the heating agent, such as e.g. amount of inert gas therein, gas composition, its temperature etc. If the required property of the heating agent is not met, the sensor 54 may via line 55 trigger the supply 53 to deliver proper heating agent add-on via line 53 to the heating agent via the chamber 10, and the heater 48 may be required to increase the temperature of the heating agent. As indicated above, the heating agent also serves to prevent any risk of explosions inside the chamber 10.
[0097] The second component(s), in the present case exemplified as pitch 7, will be supplied from a tank or reservoir 8 via one or more lines 9, the pitch being supplied according to required weight value thereof and in a pre-heated state to have a satisfactory fluid flow into the chamber 10. If it is desired to have not only one secondary component, but at least two, additional reservoir(s) and associated supply lines may be provided, as indicated by references numeral 7 and 8 on
[0098] When a supply of secondary component(s) is made to the chamber 10 via line(s) 9; or 9; 9, the fan 47 is made inoperative to avoid e.g. a mist of small particles of the secondary component(s) to be drawn to the filter unit 46 and its filter bags 46, thereby avoiding a potential clogging of the bags. However, the sets 13, 14 ; 13; 14 of shovels will rotate in order to aid the secondary components to settle on or interact with the primary component(s).
[0099] Once the secondary component(s) have settled onto or have interacted with the primary components, then the fan 47 may be re-started, or await re-starting until the made product material 10 has been discharged from the chamber 10 and a new batch of primary component(s) is fed into the chamber 10 for processing therein.
[0100] During the heating process, the sets 13, 14 ; 13; 14 of shovels will rotate and the fan will operate to maintain a circulation of heating agent.
[0101] The heating agent will not only heat the primary component(s), e.g. coke, but also provide a drying function to dry off any unwanted moisture in or on such primary components. Thus, the heating agent also serves as drying agent. Using this approach along with the second mode of operation, there is achieved also control as regards moisture in case there is water or other liquids present in or on the primary components and which in the context are to be considered as pollutions and will be a bar to obtain an optimal production result, the control being achieved by having a combined heating and drying process in the homogenization chamber 10.
[0102] As indicated on
[0103] An advantage of the second mode of operation is that the electrode mass material 10 in this case also becomes homogenized as regards temperature in a repetitive manner. Thereby, complaints related to electrode mass material 10 of poor or insufficient quality will be non-existent.
[0104] As indicated above, it is also possible to a certain extent to combine the first and second modes of operation. In such a case, heating of the container(s) having the largest particle size(s) takes place or the containers having large particles of different sizes, respectively, are heated, i.e. causing heating of the primary components which take the longest time to heat all the way into the particle nucleus.
[0105] However, it may be conceivable that it is not required to heat the larger ones of the particles all the way into the nucleus thereof, but merely e.g. halfway towards the nucleus so that there obtained a satisfactory application of pitch onto the available surface of the coke before the lower nucleus temperature causes the pitch to solidify. Such a manner to carry out the process may yield a higher consumption of pitch than if the coke is heated enough to cause the nucleus of the primary component to have a desirable temperature. The critical point to be considered is that the rest of the mixture should be satisfactorily homogenized before the pitch is introduced and is caused to settle on or interact with the primary components and be cooled or solidified/get a higher viscosity property on the surface of the larger particles.
[0106] The processing chamber 10 and the at least two sets of rotary shovels 13, 14; 13 14 are suitably configured to process primary components 4; 5; 6 which are of a single type of material. As described earlier, homogenizing action is performed by the sets 13; 14; 13; 14 of rotary shovels.
[0107] However, the primary components could just as well be of mutually different types of material. In a further variant, the primary components to be processed could be a mixture of differently sized particles, or they could be a mixture of particles having substantially same size or weight.
[0108] In e.g. the production of electrode product material the primary components are normally comprised of batches having mutually different particle size. When all batches are supplied into the chamber 10 to be homogenized simultaneously, there may be a tendency that a comparatively larger amount of the secondary component(s), e.g. a binder such as pitch, will interact with, settle on or adhere onto the smallest particle size components than onto the larger particle size components supplied into the chamber 10. Such a situation is not desirable, as it will yield a much higher consumption of secondary component(s) than necessary.
[0109] It is therefore advantageous to supply in a first step the primary components which have a larger particle size, e.g. components 4 and 5, into the chamber 10 and homogenize these components and add the secondary component 7; 7 into the chamber 10 to interact with or adhere onto these larger primary components, beforein a second stepthe primary components having smallest particle size, e.g. components 6, are added into the chamber 10 and are caused to be homogenized with the primary components having the larger particle size and which have already interacted with the secondary component(s) 7; 7 and an amount of secondary components 7; 7 is added into the chamber 10 to interact with or adhere onto the smaller particle size primary components 6 and as well as on the larger particle size components 4; 5.
[0110] An important aspect of this exemplary use of the invention is that the layer of pitch on the primary components should have as uniform thickness as possible. The primary components 4; 5; 6 will, according to the invention, obtain approximately the same amount of surface thickness of the secondary component(s) 7; 7.
[0111] As indicated on
[0112] The direction of rotation of the shafts 25; 26 of at least one of the at least two sets 13; 14; 13; 14 of shovels is optionally reversible upon a phase of operation involving the final product to leave the processing chamber. For certain types of final product material leaving the chamber 10, such reversed direction of rotation will in an efficient manner enhance discharging of the final product from the chamber 10 when the doors 42; 43 in the bottom region or floor 40, 41 of the chamber 10 of the homogenizer 10 open to provide a discharge position for the material 10, as indicated on
[0113] As described in the exemplifying embodiments above, the at least one secondary component is a binder agent for the primary components. In another embodiment, the secondary component(s) could have properties other than being a binder agent, or at least one of the secondary components could have other properties. As such, it could be visualized that a first type of secondary component is applied onto the primary components to seal pores in the primary components, and the binder agent as second type of secondary component is subsequently applied.
[0114] In another application of the invention, the primary components need not be petroleum coke, but could be any other type of material(s) to be mixed with the secondary component(s). As such, it is contemplated that a part of the primary components could be in a fine particulate material, e.g. in powder form, and could be mixed into the pitch material and the mixture supplied into the chamber 10 as the secondary component(s). The advantage of such approach is that a uniform mixture of pitch and fine particulate material, e.g. powder is supplied to interact with the homogenized primary components already in the chamber.
[0115] Such an approach, i.e. mixing a fine particulate material, such as powder, into the pitch will still yield sprayable secondary component(s), and an improved coverage on the primary components already in the chamber 10 is obtained. However, the viscosity will increase and may in certain cases yield not optimal coverage. In such a case, a volatile component, e.g. Hexan, could be added to the mixture, although other volatile components could be used.
[0116] As an alternative, said powder and said pitch could be supplied into the chamber 10 simultaneously from different locations.
[0117] Still another approach could be to let a secondary component, such as pitch, be supplied to the chamber 10 to interact with/settle on the surface of the primary components in the chamber, and then in a next step supply a fine, particulate material, e.g. powder, into the chamber to interact with the pitch already on or having interacted with the primary components. Such fine particulate material could be of the same type of material as the primary components or with same material properties as the primary components, although it may be of a type entirely different from the material of the primary components.
[0118] In other applications than the present one, the secondary component(s) need not be a binder or be a material in liquid form. In general, it could be in fluid form or as a fine particulate material, e.g. powder.
[0119] It could in a particular application be e.g. one of: a plasma, a gas, a gas having the property of being able to condense and settle on cold primary components, or a powder.
[0120] If a powder is applied, it should be able to adhere to the primary components, suitably by aid of static electricity or the primary components having a slightly sticky surface. In such a case, it could also be envisaged that application of heat into the chamber 10 could change the properties of the powder, e.g. to melt and become sticky, to melt and subsequently solidify, to melt and migrate into the primary components, to change its adherence to the primary components, or change its physical appearance related to e.g. evenness or colour.
[0121] It could also be envisaged that interaction of the secondary component(s) with the primary component(s) could imply that such secondary component(s) will e.g.: [0122] migrate into the body of the first components, [0123] change surface properties of the primary component, [0124] cause a chemical reaction between the two types of components, or [0125] cause the second component to adhere to the first components and be transformable into another property when subjected to heat, artificial ultraviolet light or another second component of a different type.
[0126] Other variations as regards use of the method and the device are all within the framework of the present invention and easily put to practice by the average expert in the art.
[0127] The use of the present invention, in particular used with the novel sets of shovels will result in substantial advantages over the prior art solutions, inter alia: [0128] 1. Reduction of formation of cracks in cast electrodes 12 due to the electrodes being made from a completely homogeneous mixture of coke and pitch. [0129] 2. Reduction of electrode consumption because the electric current flux is uniform from the entire surface of the electrode. [0130] 3. Reduction of electrode consumption does yield formation of damages or any concavities on the electrode surface. [0131] 4. Reduction of electrode residues in manufactured aluminium, implying a cleaner quality of the manufactured aluminium bars. [0132] 5. Less need for removal of slag residues from the melting bath. [0133] 6. Less operator costs due to longer life of the electrode. [0134] 7. Less complaints both in-house and externally when selling electrodes to other manufacturers of aluminium bars. [0135] 8. Increased sale of high quality electrodes is made possible. [0136] 9. Reduction of power consumption in the manufacturing of aluminium. [0137] 10. Reduced power consumption in making electrode mass material 10. [0138] 11. Reduced costs when casting electrodes 12 due to less need for removing electrodes having cracks and milling thereof for recycling of the electrode material for re-use. [0139] 12. Less need for use of milling and sieving systems for electrodes having cracks. [0140] 13. Reduced structural volume of electrode material manufacturing plant. [0141] 14. Reduced need for electrical installations at production plants for making the electrode material. [0142] 15. Reduced operation and maintenance costs are provided due to simpler structural configuration. (Currently used components blenders require substantial amount of maintenance due to abrasive wear, and do not offer a product material being satisfactory homogeneous, although such blenders are frequently used in the metals industry and foundries).
[0143] As indicated in the introduction and the detailed description, the current invention is not all limited to the making of electrode manufacturing material.
[0144] Indeed, all typical processes which involve blending of particles with one or more types of binders are always dependent on obtaining a homogeneous compound or mixture material in order to subsequently be able to manufacture a final product having optimal quality.
[0145] Most current technical solutions related to such processes all have deficiencies as regards efficiency of homogenization. One example of such a process is the manufacturing of asphalt, irrespective of whether it is warm asphalt or cold asphalt.