EP3810726B1 - Method for producing a coking product - Google Patents

Description

The invention relates to a process for the production of a coke product formed by solidification of a carbon support material intended for use in the production of metals, metal alloys and metallurgical products or as an intermediate product for the production of graphite elements and having a near-net-shape, monolithic geometry and a density of at least 1.4 g/cm ³ .

Coke products of the type produced and configured according to the invention are used, for example, as anodes in the production of aluminum or as electrodes in the melting or metallurgical treatment of steels in electric arc furnaces and in reduction furnaces.

A review of the current state of the art in the manufacture of electrodes for the metallurgical treatment of metals or metal alloys can be found in the article written by Rick Adams, Wilhelm Frohs, Hubert Jäger and Keith Roussel and published by the American Carbon Society in 2007 "Graphite Electrode and Needle Coke Development" available for download at URL http://acs.omnibooksonline.com/data/papers/ 2007_D031(K).pdf.

Accordingly, carbon in a solid form, typically as coke, is provided for the production of coke products of the type under discussion here. The production of the coke takes place in a conventional manner, usually from residues in the refining of petroleum or other petrochemical processes. In this case, carbon carriers that can be coked, such as residues occurring in the distillation of petroleum or comparable carbon carriers, are subjected to a coking process. Alternatively, coal tar pitch is used as the starting product for coking. If necessary, the so-called green coke also undergoes a calcination process in order to eliminate the volatile hydrocarbons that are still present, particularly in petroleum coke.

So-called needle coke is usually used for applications in which the highest demands are placed on mechanical strength while at the same time minimizing thermal expansion, such as in the melting or metallurgical treatment of steel in an electric arc furnace. This represents the highest level of quality and can only be produced with increased effort ( DE 10 2004 035 934 A1 ). For applications where lower requirements are placed on the mechanical strength or the thermal expansion behavior, the expensive needle coke can be partially or completely replaced by a cheaper type of coke or one of the other carbon carriers (eg anthracite coal).

The coke is ground to a pourable quantity of grains, from which typically eight grain fractions are separated by sieving. Coke of different grain fractions is usually mixed to form a coke grain mixture with a grain size distribution that is considered optimal with regard to the properties to be set for the graphite element. Typically, this creates mixtures that are one-third dust and two-thirds grain to ensure adequate density. Here it is assumed that the coke dust fills the gaps between the coke grains. Additives such as iron oxide can be added to the respective mixture. Iron oxide causes a minimization of the irreversible thermal expansion of the coke ("puffing"), which occurs in the subsequent heat treatments when sulfur still present in the coke is expelled from the carbon lattice.

The grain mixture, which is typically preheated to shorten the process times, is mixed with a binder, such as tar pitch, stearic acid or mixtures of these binders, to form a plastically deformable, pasty, homogeneously mixed mass, the binder content of which is typically 20-24% by weight. The resulting carbon binder mass, which is also referred to as "green mass" in technical jargon, is now formed into a so-called "green body" by pressing, extruding, shaking or tamping: During this forming process, the temperature is below the mixing temperature, so that at this point in time there is a tough, very highly viscous mass.

The green compacts are then slowly heated to a temperature of typically 800 to 950 °C in the absence of oxygen. During this burning process, part of the binder decomposes into gas, which has to escape from the green body. This gas development causes a slowly progressive warming, because otherwise, as a result of the gas pressure arising in the green body, cracking and associated instability of the carbon or graphite element to be produced could occur.

Depending on the binder system used, about a third of the mass of the binder used is lost during the firing process. The binder degassing from the green body leaves cavities in the intermediate product obtained after firing, as a result of which the intermediate product has a reduced density. As a rule, this is not sufficient for the production of carbon or graphite elements, from which high electrical conductivity and high strength are required, such as graphite electrodes for steel melting or treatment. Therefore, the intermediate product obtained after the first firing before the Further processing typically subjected to a so-called "impregnation". For this purpose, a heated impregnating agent that has a lower viscosity than the binder originally used, typically tar pitch, is pressed into the intermediate product in order to fill the pores present there. The intermediate product is then fired again. In the process, part of the previously pressed-in impregnating agent evaporates, with the result that the intermediate product inevitably has open pores that are not filled with carbon even after an impregnation step. Accordingly, if necessary, the impregnation process must be repeated until the intermediate product has the density required for its further processing.

For further processing into a graphite element of the highest quality, the intermediate product is subjected to a graphitization process. The carbon contained in the intermediate product is converted into graphite by heating to approx. 2800 °C, which is characterized by an increasingly three-dimensional order of the carbon atoms. The so-called "Acheson process" or the more economical "Castner process", the so-called longitudinal graphitization (LWG), are usually used here. The process and success of the graphitization can be supported by the lowest possible sulfur and nitrogen content in the starting material and the resulting reduced tendency to puffing. The negative effect of nitrogen and sulfur still present in the intermediate product can, as mentioned, also be reduced by suitable additives such as iron oxide or a targeted temperature control during the graphitization.

Processes based on the so-called "Söderberg process" (see for example US 1,440,724A , US 1,640,735A ) avoid the hassle associated with forming a green body, firing the green body to an intermediate product, and the graphitization process in the manufacture of graphite electrodes.

At one in the US 3,365,533A In the embodiment of this method described above, a pasty carbon carrier material consisting of a mixture of granular coke and liquid tar distillate serving as a binder is filled into a tubular housing of an electrode, one end of which is placed in the furnace chamber of a reduction furnace (electric arc furnace) for the melting/reduction of For example, phosphorus, tantalum or ferromanganese from ores. The housing of the electrode consists of electrically conductive carbon steel. A current is applied to the housing of the electrode, which current is transmitted to the carbon support material filled in the housing. In this way, an arc is ignited in the furnace chamber, causing the temperatures in the area of the end of the electrode reaching into the furnace chamber to rise to over 2000 °C. As a result, there is a temperature gradient in the carbon carrier material contained in the housing of the electrode, which keeps the pasty carbon carrier material in the upper area of the electrode molten at around 200 °C. In the direction of the end of the electrode associated with the furnace chamber, the temperature of the carbon carrier increases continuously. The hydrocarbon compounds contained in the carbon material decompose in the temperature range from 400 °C to 600 °C. The gases thus released should be able to escape in the direction of the upper end of the electrode protruding into the furnace chamber. At the same time, the carbon from the hydrocarbon compounds should fill the spaces between the coke grains. As the tip of the electrode protruding into the furnace chamber is approached, this process continues until the tip of the electrode protruding into the furnace chamber as a solid, compact body has emerged from the carbon carrier material. In melting operation, the electrode wears out and has to be pushed in from above in order to maintain the arc in the furnace chamber.

At one in the DE 600 01 106 T2 described other variant of the Söderberg process is in a furnace to melt a Steel alloy also arranged an electrode with a cylindrical container, which is guided with its upper open end through the wall of the furnace. The container is formed from a conductive stainless steel. The container is charged with a non-baked lumpy electrode mass via its open upper end. On its way to the lower end of the container, which is also open, the electrode mass is liquefied by the supply of heat, which takes place via heated air guided in a central area around the container of the electrode, until it reaches the area of a plate-shaped material positioned adjacent to the lower outlet opening of the container Arrangement for coupling an electric current arrives. As a result of the high temperatures prevailing in the region of the tip of the electrode reaching into the furnace chamber, the electrode mass is also fired "in situ" there. The solid electrode strand burned from the electrode mass in this way is continuously conveyed from the lower outlet opening of the container into the furnace chamber and serves as an electrode for the supply of electrical energy, via which the arc and thus the melting process in the furnace is kept going. The problem of ensuring a specific density of the graphite element produced in this way is also not addressed here, nor is the adjustment of specific mechanical or other properties that are important for the use of coke products with which the invention is concerned.

In addition to the prior art explained above is from the US 4,472,245A discloses a process for heat treating carbonizable materials such as wood, paper, plastic, rubber, hydrocarbonaceous mineral substances, shale oil and oil sands, aimed at generating gas from the feedstocks. For this purpose, the material to be charred is introduced in bulk into the furnace chamber of an electric shaft furnace via a filling opening. A vertically oriented first electrode, carried by the lid of the furnace, protrudes into the furnace chamber treated material is sufficient. A second electrode is placed at the bottom of the furnace chamber. When an electric voltage is applied to the electrodes, electric current runs through the material placed in the furnace, which is heated in this way. The resulting gas, which is in particular H ₂ and CO, is drawn off from the furnace via openings. The residual products in the form of loose ash or loose pyrolysis coke are drawn off through an opening in the bottom of the furnace.

Furthermore, from the U.S. 2008/256852 A1 a multi-stage petroleum refinery process is known in which a coal-oil mixture is coked in a second refining step. For this purpose, the coal-oil mixture is introduced into a delayed coker and heated. A carbon product is produced as a by-product, which is said to be suitable for use as an anode in the production of aluminum. Further details on the manner in which the coking process is carried out are not explained here.

From the US 4,106,996A Finally, a process for improving the mechanical resistance of coke is known, in which a mixture ("liquor") of finely ground coal and oil with an oil content of 5-30% by weight is first formed into briquettes at 100 °C and then into round pellets will. These pellets are fed into a coking oven where they are coked under the influence of a hot gas stream which is passed through the pellets through openings at the bottom of the oven.

Based on the prior art explained above, the task was to name a process with which a coke product can be produced inexpensively which, due to its high density, can be used directly in the production of metals, metal alloys and metallurgical products or as an intermediate product For the production of Corresponding graphite elements can be used, the properties of which are subject to the highest demands.

The invention has solved this problem by the method specified in claim 1.

Advantageous refinements of the invention are specified in the dependent claims and, like the general inventive concept, are explained in detail below.

1. a) Bereitstellen eines Behälters, der einen Innenraum umgrenzt und eine Einfüllöffnung zum Einfüllen eines fließ- oder schüttfähigen Kohlenstoffträgermaterials in den Innenraum sowie eine Heizeinrichtung zum Erwärmen des in den Innenraum des Behälters gefüllten Kohlenstoffträgermaterials umfasst;
2. b) Einbringen des Kohlenstoffträgermaterials über die Einfüllöffnung in den Innenraum des Behälters, wobei das Kohlenstoffträgermaterial eine verflüssigbare, verkokbare Kohlenstoffkomponente sowie optional feste, insbesondere verkokbare Kohlenstoffkomponenten und ebenso optional Additive umfasst, welche zur Einstellung der Eigenschaften des Kohlenstoffträgermaterials dienen;
3. c) Erwärmen des in den Innenraum des Behälters gefüllten Kohlenstoffträgermaterials mittels der Heizeinrichtung auf eine Verkokungstemperatur, wobei das auf die jeweilige Verkokungstemperatur erwärmte Kohlenstoffträgermaterial jeweils so lange bei der Verkokungstemperatur gehalten wird, bis das auf der Verkokungstemperatur gehaltene Kohlenstoffträgermaterial durch Verkokung zu dem Verkokungsprodukt verfestigt ist;
   • wobei während des Arbeitsschritts c) eine längs der Längsachse des Behälters ausgerichtete Relativbewegung zwischen dem jeweils erwärmten Kohlenstoffträgermaterial und der Heizeinrichtung stattfindet,
   • indem die von der Heizeinrichtung abgegebene Wärme jeweils nur ein sich über einen bestimmten Teilabschnitt der Höhe des Innenraums des Behälters erstreckendes Teilvolumen des in den Innenraum gefüllten Kohlenstoffträgermaterials erfasst,
     und
   • entweder das in den Innenraum des Behälters gefüllte Kohlenstoffträgermaterial stillsteht, während die Heizzone ausgehend von dem in Schwerkraftrichtung unten angeordneten Boden entgegen der Schwerkraftrichtung in Richtung des oberen Endes des Behälters bewegt wird,
     oder
   • die Heizeinrichtung ortsfest angeordnet ist und das in den Behälter gefüllte Kohlenstoffträgermaterial relativ zur Heizeinrichtung bewegt wird, indem entweder der Behälter mit dem in ihn gefüllten Kohlenstoffträgermaterial entlang der feststehenden Heizeinrichtung bewegt wird oder im Boden des Behälters eine Abzugsöffnung vorgesehen ist, über die das Verkokungsprodukt als aus dem jeweils verfestigten Kohlenstoffträgermaterial gebildeter Strang kontinuierlich aus dem Behälter entnommen wird (Arbeitsschritt e)); und
4. d) wobei Gas, welches während des Erwärmens und Haltens (Arbeitsschritt c)) aus dem Kohlenstoffträgermaterial entweicht, aus dem Behälter abgeleitet wird;
5. e) Entnehmen des Verkokungsprodukts aus dem Behälter.

The method according to the invention for producing a coke product therefore comprises the following work steps:

1. a) providing a container which delimits an interior space and comprises a filling opening for filling a flowable or pourable carbon support material into the interior space and a heating device for heating the carbon support material filled into the interior space of the container;
2. b) introducing the carbon carrier material into the interior of the container via the filling opening, the carbon carrier material comprising a liquefiable, carbonizable carbon component and optionally solid, in particular carbonizable carbon components and also optionally additives which are used to adjust the properties of the carbon carrier material;
3. c) heating of the carbon carrier material filled into the interior of the container by means of the heating device to a coking temperature, wherein the carbon carrier material heated to the respective coking temperature is kept at the coking temperature until the carbon carrier material held at the coking temperature is solidified by coking to form the coking product;
   • wherein during step c) a relative movement, aligned along the longitudinal axis of the container, takes place between the respectively heated carbon support material and the heating device,
   • in that the heat given off by the heating device covers only a partial volume of the carbon carrier material filled in the interior space that extends over a specific partial section of the height of the interior space of the container,
     and
   • either the carbon carrier material filled into the interior of the container stands still while the heating zone, starting from the bottom arranged in the direction of gravity, is moved counter to the direction of gravity in the direction of the upper end of the container,
     or
   • the heating device is arranged in a stationary manner and the carbon carrier material filled in the container is moved relative to the heating device, either by moving the container with the carbon carrier material filled in it along the fixed heating device or by providing a vent opening in the bottom of the container through which the coke product can be removed the strand formed from the respectively solidified carbon support material is continuously removed from the container (work step e)); and
4. d) wherein gas escaping from the carbon support material during heating and holding (step c)) is discharged from the container;
5. e) removing the char from the container.

• f) Brennen des Verkokungsprodukts;
• g) Imprägnieren des Verkokungsprodukts mit einem flüssigen kohlenstoffbasierten Füllmittel und anschließendes erneutes Brennen des imprägnierten Verkokungsprodukts;
• h) Erzeugen eines Graphitprodukts durch Graphitieren des Verkokungsprodukts.

In order to further refine the coking products produced according to the invention by completing the work steps a) - e) that are necessary according to the invention, in particular to increase the quality of the graphitized products, they can optionally also go through the following work steps after work step e):

• f) burning the char;
• g) impregnating the char with a liquid carbon-based filler and then refiring the impregnated char;
• h) producing a graphite product by graphitizing the coke product.

Unlike the conventional method, in which a granular starting material is used, which is converted into a moldable mass by mixing with a binder to form a green body, which is then subjected to a coking treatment, the method according to the invention starts from a flowable starting product , namely a carbon support material, the essential component of which is a liquid or liquefiable carbon support, the carbon support material also containing solid carbon components and other solid or liquid components (additives), but without losing its liquid character.

Additives include, for example, iron oxide or titanium oxide to reduce the puffing effect, a boron source such as pure boron or

Boron carbide, to improve the crystal structure and thereby reduce the coefficient of thermal expansion, or carbon or graphite fibers are used, which contribute to improving the mechanical properties and also to reducing the coefficient of thermal expansion.

In order to produce a coking product whose mechanical, thermal and electrical properties meet the highest requirements, a carbon-rich, coking product is used as the carbon carrier material, which is already liquid at room temperature or is brought into the flowable state by heating and the associated melting, but in any case is liquid during coke access.

The carbon support materials used according to the invention typically arise in the processing of petroleum from the heavy fraction, as residues in the distillation of petroleum, from coal tar derivatives, from liquid-phase pyrolysis (other free-flowing organic components). The use of products from the processing of biomass, such as cellulose, sugar or starch, is also conceivable. The materials mentioned above are only mentioned here as examples. Of course, other carbon-containing substances which are present in liquid form or which can be liquefied by melting and which can be coked can also be used for the purposes according to the invention. Accordingly, the liquid or liquefiable carbon component of the carbon carrier material consists in particular of at least one component from the following group: "Residues from the distillation of petroleum and the use of coal products such as tar and its derivatives, pitch, free-flowing bitumen, resins or products from processing of biomass such as cellulose, sugar and starch".

As a solid carbon component, at least one component from the following group can be present in the carbon carrier material used according to the invention: "granular form of coke, coal, bitumen in solid form, lignites, anthracite coal, graphite, materials from the recycling of carbon fibers", although these materials are also only mentioned as examples and, of course, other carbon-containing residues that are in solid form and can be coked can also be used for the purposes according to the invention.

Coking products produced according to the invention can be used directly as carbon suppliers for those applications in which they serve as reactants or electrodes for chemical and electrochemical reactions. An important field of application here is the use in plants for producing aluminum, in which coking products produced according to the invention can be used as anodes or cathodes, in particular as anodes, without having to undergo further work steps to change their structure or density.

If higher mechanical, electrical and in particular thermal requirements are placed on the carbonization products according to the invention, the optional work steps f) - h) already mentioned above can be completed after work steps a) - e) of the process according to the invention. In this way, carbonization products produced according to the invention can be used as an intermediate product for the production of high-quality graphite elements, such as are required, for example, as electrodes in melting or in the metallurgical treatment of steels in an electric steel works.

Since the invention uses a carbon carrier material consisting of predominantly liquid or liquefiable components as the starting product, it is possible to produce a coke product with low porosity. The procedure according to the invention ensures that the smallest possible amount of gas bubbles is included in the coke product obtained. The dimensions of the shape of the invention The containers that determine the coking product produced can be chosen so that they correspond to the final dimension adapted for the respective application, taking into account any machining allowance that may be required.

The container provided according to the invention can be manufactured in a manner known per se from a sufficiently temperature-resistant sheet steel.

In order to facilitate the removal of the finished carbonized product from the container in step e), the container can be covered with a sliding layer at least in sections on its inner surfaces bordering the interior of the container. For this purpose, a separately prefabricated liner lying tightly against the inner surface of the container can be introduced into the interior of the container, or a coating consisting of a suitable material can be applied directly to the inner surface in question. A light metal material, in particular an aluminum material, but also a thin sheet steel can be used as the material for the sliding surface.

In step b) of the method according to the invention, the flowable carbon carrier material is introduced into the interior of the container via the filling opening of the container. The filling opening can be formed by a filling tube or the like, which is guided through a cover, a wall or a lid of the container into the interior space delimited by it.

In order to increase the flowability of the liquid or fusible carbon component placed in the container according to the invention, it may be expedient to preheat the carbon component itself or the entire carbon carrier material before filling it into the interior of the container. The preheating is preferably carried out in such a way that the liquid component, if any, is present fusible carbon component is already liquefied when it enters the container. However, the heating in the container can also take place in such a way that an optimally liquid state of the carbon carrier material is first produced and then the coking process begins.

According to a first variant, the filling can be carried out in such a way that the total amount of carbon carrier material to be coked is first filled into the container (step b)) and only after filling is it heated to the coking temperature and maintained at the coking temperature (step c)), ie the heating of the carbon material only begins after the filling of the carbon carrier material (step b)) has been completed.

According to a second variant, it is also possible to start heating a partial volume of the total amount of carbon carrier material (step c)) that is filled into the container and required for the production of the carbonization product, while further carbon carrier material is still being filled into the interior (step b). ).

While the first variant enables a simplified process control, the second variant enables the production of particularly dense, high-quality coke products with minimized porosity.

The coking temperatures set according to the invention during the coking process (step c)) are typically 450-900° C., with coking temperatures of at least 600° C. within a practical coking time, complete coking in the technical sense being able to be reliably achieved even with large-volume coking products.

At the same time, setting the coking temperature in the range of 450 - 900 °C ensures that there is always sufficient free-flowing carbon carrier material available in the process to automatically fill the pores created by the degassing processes in the partial volumes of the carbon carrier material that are in the coking process with subsequent flowing carbon carrier material . The flowable carbon carrier material that follows and fills the openings and cavities left behind by the gas unavoidably produced during coking ensures, according to the invention, an optimally high density of the coking product obtained.

It has been shown that in the method according to the invention, the electrical conductivity of the products produced according to the invention can be directly influenced by adjusting the coking temperature. The electrical conductivity increases with increasing coking temperature. By setting high coking temperatures, electrical conductivities can therefore already be achieved in the coking product produced according to the invention, which allow direct graphitization or another immediate use of these products after the coking process according to the invention. For example, products produced according to the invention can be used directly as anodes or cathodes, in particular as anodes, in the production of aluminum.

At a coking temperature of at least 650 °C, in particular at least 700 °C, there is a further significant reduction in the electrical resistance, with optimally low resistances of 10-50 ohms and an associated optimal electrical conductivity at coking temperatures of at least 800 °C resulting . By suitably setting the coking temperature of usually at least 800° C., longitudinal graphitization of the coke product can already be achieved in the course of the process according to the invention.

If the carbonization temperature is above an upper limit of 1200° C., the conductivity no longer improves, so that in practice the carbonization temperature range can be limited to at most this upper limit.

1. a) sicherzustellen, dass eine ausreichende Menge an flüssigem Kohlenstoffträgermaterial vorhanden ist, um eine automatische Nachfüllung der entstandenen Poren zur gewährleisten,
2. b) gleichzeitig die Menge an flüssigem Kohlenstoffträgermaterial so gering wie möglich zu halten, um Ausgasung und Abtransport der sich bildenden Gasblasen zu begünstigen,
3. c) den Verkokungsvorgang zügig ablaufen zu lassen
   und
4. d) ein spontanes Verkoken und damit einhergehend ein "Einfrieren" von Gasblasen zu vermeiden.

In order to ensure that as few gas bubbles as possible are trapped in the coke, the invention provides a suitable temperature and quantity regime, in particular when passing through the temperature range of 450 - 600°C

1. a) ensure that there is sufficient liquid carbon support material to ensure automatic refilling of the pores formed,
2. b) at the same time keeping the amount of liquid carbon carrier material as low as possible in order to promote outgassing and the removal of the gas bubbles that form,
3. c) to let the coking process run quickly
   and
4. d) to avoid spontaneous coking and the associated "freezing" of gas bubbles.

The coking time, over which the carbon support material is kept at the respective coking temperature, is directly dependent on the respective heated volume. In any case, the coking time is to be dimensioned in such a way that the carbon support material kept at the coking temperature is completely coked in the technical sense after the end of the coking time. The coking time depends on the volume to be coked and, in the case of successive filling, on the progress of the filling process. Typical In practice, coking times for large-volume coking products, such as electrodes, are between 6 hours and 96 hours. When producing coke products with smaller volumes or small cross-sections, the coke time can also be less than an hour.

The atmosphere present in the interior of the container can be sucked off in order to support the escape of the gas produced during coking from the carbon carrier material. This creates a negative pressure in the interior of the container above the carbon carrier material filled in it, which can reach as far as a vacuum. A suitable absolute pressure for this is in the range from 1 to 50 hPa.

The manner of filling the mold (step b)) and heating (step c)) can be selected in the process according to the invention depending on the requirements placed on the density distribution of the coke product produced according to the invention. If, for example, there is a requirement that in the outer edge areas of the coke products there should be maximum density over a sufficient thickness, while a certain residual porosity is accepted in the central core area, it can be sufficient if a stationary container, the total volume filled into the container, is sufficient is arranged on flowable carbon support material detecting heating device. In this case, the coking process proceeds from the edge area of the carbon support material adjacent to the inner surface of the container, which is affected first and most intensively by the heat generated by the heating device, towards the core area of the carbon support material. The gas bubbles formed during coking can escape through the core area of the carbon carrier material, which remains liquid for a long time. At the same time, liquid carbon carrier material pushes out of the liquid core area into the pores left by the gas bubbles in the already carbonized edge area, so that the finished coked product has an optimally sealed edge area of considerable thickness adjusts Only in the last stage of coking, namely when the central core area is also coked, can gas bubbles be trapped there. However, the diameter of the core area affected by the resulting porosity is so small compared to the thickness of the optimally dense surface layer of the coke product produced according to the invention that it is negligible in applications such as electrodes for reduction furnaces.

A porosity that is minimized over the entire cross section of the carbonization product produced according to the invention and, as a result, an optimized density, can be achieved in that during step c) a relative movement, aligned along the longitudinal axis of the mold, takes place between the respectively heated carbon support material and the heating zone generated by the heating device. This relative movement can take place continuously or in steps. In the case of a continuous relative movement, the speed of this movement can also be varied as a function of the progress of the coking of the carbon support material. Likewise, in the case of an incremental relative movement, in which the heating zone or container remains in one position for a certain dwell time before the heating zone or container moves to the next position, the exposure time to the heat can depend on the volume covered by the heating zone Carbon support material can be controlled by adjusting the residence time.

By moving the heating zone relative to the carbon support material or moving the carbon support material relative to the heating zone, it is possible to ensure that the coking process not only moves from the outer edge to the central core area of the volume of the in the interior of the container filled carbon support material progresses, but at the same time also in the direction of relative movement. In this way, an even growth of the each coked volume of the carbon support material is achieved over the entire cross-section, and it is consequently ensured that there is also a high density in the core area of the coke product obtained according to the invention.

According to a first variant of this embodiment of the method according to the invention, the heat emitted by the heating device in the heating zone only covers a partial volume of the carbon carrier material filled in the interior space that extends over a specific partial section of the height of the interior space of the container, with the carbon carrier material filled in the interior space during the heating (step c)) stands still, whereas the heating zone generated by the respective heating device, starting from the bottom arranged in the direction of gravity, is moved counter to the direction of gravity in the direction of the upper end of the container. The gas bubbles escaping from the partial volume of the carbon carrier material contained in the interior of the container that has been heated to the coking temperature by the heating device can, in this embodiment, be expelled by the liquid carbon carrier material that is above the partial volume of the carbon carrier material that is in the coking process (work step c)) and is covered by the heat of the heating device escape upwards against the direction of gravity, while at the same time, due to the effect of gravity, liquid carbon carrier material presses with gravitational pressure into the openings and cavities left by the gas bubbles in the carbon carrier material that has already coked and fills them, so that an overall dense, largely pore-free coking product is automatically obtained.

It has proven to be particularly advantageous here that, in the method according to the invention, the filling of the container and the heating of the volume of carbon carrier material contained in the container can take place at the same time. In this way, the amount of flowable carbon support material during the coking of each of the heat of the heating device is above this partial volume, so that on the one hand the distance covered by the gas bubbles through the still liquid carbon carrier material is optimally short, but on the other hand the column of flowable carbon carrier material weighing on the carbon carrier material that has already coked is so large that it is always a sufficient amount of flowable carbon support material is present above the already coked carbon support material partial volume and optimally the displacement of the flowable carbon support material into the pores of the already coked carbon support material is supported by the weight of the still liquid carbon support material.

With the container mounted in a stationary manner, a relative movement between the heating zone and the carbon support material contained in the container can be brought about by the heating device producing the heating zone being moved along the container.

Alternatively, however, it is also possible to provide a stationarily mounted heating device that extends over the entire length of the volume of carbon carrier material filled in the container and is divided into a plurality of heating segments in the longitudinal direction of the container. These can then be activated and deactivated sequentially so that continuous or stepwise movement of the heating zone generated by the heating segments of the heater along the container is achieved.

In another variant of the method according to the invention, the heat given off by the heating device in the heating zone also only covers a partial volume of the carbon carrier material filled in the interior space, extending over a specific partial section of the height of the interior space of the container, with the heating device being arranged stationary here, however. while the carbon support material filled in the container is moved relative to the heating zone created by the heater. In principle, the container with the filled in it can do this Carbon support material are moved along the fixed heater.

In a particularly productive embodiment of this variant of the process, which is based on a fixed heating device and which also produces coking products of the best possible quality, the container is installed in a stationary manner, with a vent opening being provided in the bottom of the container through which the coking product continuously flows out as a strand formed from the solidified carbon carrier material removed from the container (step e)). In this configuration, the container is designed in the manner of a casting mold. At the same time, the heating device is mounted on the container and the withdrawal speed at which the coked coke product is continuously removed from the container as a strand is selected in such a way that the carbon carrier material filled into the container in a flowable state is on its way to the withdrawal opening in the technical sense is fully coked and accordingly solidified. In addition to the increased productivity, there is also the particular advantage here that the volume of flowable carbon carrier material that is above the already coked partial volume of the carbon carrier material in the container can be adjusted in such a way that on the one hand the path leading from the in the coking process (work step c)) located partial volume emerging gas bubbles must be covered, is short and on the other hand always enough liquid carbon support material is available to fill the pores left by the gas bubbles in the already coked carbon support material. The carbonized product drawn off from the container as a strand can optionally be cooled down more quickly in order to enable speedy further processing. Coke products of the respectively desired length can be separated from the coke product strand obtained.

In the embodiment variants in which there is a relative movement between the carbon support material and the heat source, the depends The speed of the relative movement depends on the diameter or cross-section of the product to be produced. The speed decreases proportionally with increasing diameter or cross-sectional size because of the coking of the volume of carbon support material covered by the heating zone. When producing cylindrical electrodes with diameters that are typical in practice, the speed of the relative movement between the heating zone and the carbon carrier material contained in the container is typically in the range of 0.025-1.5 m/h, in particular 0.05-0.5 m/h .

The degassing (step d)) of the gas escaping from the carbon carrier material in the coking process (step c)) can be supported by the carbon carrier material contained in the container being set in motion at least temporarily. For this purpose, for example, a vibration device or the like can be provided, which excites the carbon carrier material contained in the container as a whole or in certain areas to vibrate, which are ideally in the range from 0.5 Hz to 50 kHz.

The heating device used according to the invention for heating the carbon carrier material can be designed in such a way that it causes a specific temperature profile within the carbon carrier material contained in the container and which is respectively covered by the heat of the heating device. For example, it can be expedient, particularly in the case of process variants in which there is a relative movement between the heating zone generated by the respective heating device and the carbon carrier material, to operate the heating device in such a way that the partial volume of carbon carrier material newly entering the effective range of the heating device slowly expands the respective coking temperature is brought, so that the heating power acting on the respective partial volume of carbon carrier material increases, the further the respective partial volume into the effective range of the heating device retracts and the longer it is exposed to the heat emitted by the heater.

The process according to the invention provides coking products which are already given a geometry close to their final dimensions during coking. This eliminates the work steps of coke preparation, mixing, shaping and first firing that are conventional in the production of electrodes, and it opens up the possibility of also dispensing with impregnation and a second firing of the coke product produced according to the invention in order to produce a fully graphitized end product. Thus, the process according to the invention provides a coke product of high strength and density even without impregnation. These are characterized in that they have an average density of at least 1.4 g/cm ³ , densities of at least 1.5 g/cm ³ being regularly achieved.

Due to the fact that a monolithic structure close to the final dimensions is already realized in the coking process in the method according to the invention, this is characterized by high mechanical strength. Furthermore, the spatial characteristics of the physico-chemical coke properties can be controlled by the targeted application of heat. In particular, a high electrical conductivity in the longitudinal direction and a low thermal expansion coefficient can be set in this way.

Figuren 1a - 1d

eine erste Vorrichtung zur Herstellung eines Verkokungsprodukts zu vier zeitlich in gleichen Abständen beabstandeten Betriebszeitpunkten jeweils in einem Schnitt längs der Längsachse der Vorrichtung;

Figuren 2a - 2d

eine zweite Vorrichtung zur Herstellung eines Verkokungsprodukts zu vier zeitlich in gleichen Abständen beabstandeten Betriebszeitpunkten jeweils in einem Schnitt längs der Längsachse der Vorrichtung;

Fig.3

eine dritte Vorrichtung zur Herstellung eines Verkokungsprodukts in einem Schnitt längs der Längsachse der Vorrichtung;

Fig. 4a

eine vierte Vorrichtung zur Herstellung eines Verkokungsprodukts in einem nicht erfindungsgemäßen Verfahren in einem Schnitt längs der Längsachse der Vorrichtung;

Fig. 4b

ein in der in Fig. 4a dargestellten Vorrichtung erzeugtes Verkokungsprodukt in einem Längsschnitt.

The invention is explained in more detail below with reference to a drawing showing an exemplary embodiment. They each show schematically:

Figures 1a - 1d

a first device for producing a coke product in four equally spaced in time spaced operating times each in a section along the longitudinal axis of the device;

Figures 2a - 2d

a second device for producing a coke product at four equally spaced operating times, each in a section along the longitudinal axis of the device;

Fig.3

a third device for producing a coke product in a section along the longitudinal axis of the device;

Figure 4a

a fourth device for producing a coke product in a method not according to the invention in a section along the longitudinal axis of the device;

Figure 4b

one in the in Figure 4a device shown coke product generated in a longitudinal section.

The in the Figures 1a - 1d The device 1 shown for the production of a coking product VK comprises a container 2, which is aligned vertically with its longitudinal axis L and is shaped like a cylindrical tube and is made of a heat-resistant material, such as steel that is commercially available for this purpose. The container 2 delimits an interior space 3 which widens in a funnel shape in an upper section 4 in the direction of the upper edge of the container 2 .

The slender, cylindrical shape of the interior 3 is selected so that the coking product VK produced in the device 1 has an equally slender cylindrical shape at the end of the coking process completed in the device 1, which is optimally approximated to the shape that the coking product VK or have a graphite product made therefrom target. The dimensions of the coking product VK can include a machining allowance, which is required for final machining in order to give the coking product VK or a graphite product produced therefrom its prescribed dimensional accuracy or surface quality. The shape and dimensions of the cylindrical shape represented by the interior 3 of the container 2 correspond to the shape that graphite electrodes must have in order to be able to be used in electric arc furnaces of steelworks. In the same way, other forms of coking products, such as blocks formed from coked carbon support materials or the like, can be represented by the shape of the interior space 3 . Their shape can then, for example, be optimally adapted to the conditions in plants for the production of aluminum, if necessary also including the required machining allowance.

The inner surfaces of the container 2 bordering the interior 3 can be covered at least in sections as a separating layer with a thin sliding layer 5, for example made of an aluminum material, which can be in the form of a prefabricated liner and inserted into the interior 3 or by a suitable coating process in a manner known per se is applied directly to the relevant portions of the inner surfaces.

The opening present at the top of the container 2 is closed by a removable cover 6 .

A filling tube 7 for filling the interior 3 of the container 2 with a flowable carbon carrier material K is guided through the cover 6 .

In addition, a suction tube 8 is routed through the cover 6 and is connected to an evacuation device (not shown here) via which a negative pressure can be generated in the interior 3 for sucking off gases present in the interior 3 .

The underside of the container 2 stands on a base element 9 which closes the underside of the container 2 .

The device 1 also includes an electrically operated, controllable heating device 10, which is placed with its heating coils 11 in a ring and with play around the outer surface 12 of the container 2. The height H10 of the heating device 10 corresponds to a small fraction of the height H3 of the interior 3 of the container 2. For example, the height H3 can be up to 15 m, whereas the height H10 is typically only 1 m.

The heating device 10 is carried by an actuating device 13 which is set up in a manner known per se to move the heating device 10 in the vertical direction V along the container 2 . For this purpose, the adjusting device 13 can have a linear guide 14 aligned parallel to the longitudinal axis L, along which the heating device 10 can be moved by means of a linear drive 15 of the adjusting device 13 .

The device 1 also includes a device 16 which is provided for subjecting the liquid carbon carrier material K filled into the interior 3 of the container 2 to vibrations in the range from 0.5 Hz to 50 kHz. In order to achieve the most intensive effect possible on the still liquid, non-coked volume of the carbon carrier material K, the vibration device 16 can also be carried by the actuating device 13 and moved along the container 2 with the heating device 10 during the coking process. The vibration device 16 is preferably located above the heating device 10 in order to bring about the best possible effect of the movement of the still flowable carbon carrier material K that it triggers.

To produce a columnar coke product VK, the interior 3 of the container 2 is filled with flowable carbon carrier material K via the filling tube 7 until the level SK of the in the interior 3 contained carbon carrier material K is located approximately in the region of the transition between the funnel-shaped upper section 4 and the underlying cylindrical part of the interior 3.

The heating device 10 is positioned in a starting position at the lower end of the container near the bottom element 9 during the filling process.

After the container 2 has been filled with the free-flowing carbon carrier material K, the heating device 10 is supplied with electrical energy, for example, so that the partial volume of the carbon carrier material K in the effective range of the heating zone generated by the heating device 10 is gradually heated to a coking temperature of 450 - 900 °C , in particular 650 - 850 ° C, is heated. As a result of the heating, decomposition processes set in in the partial volume heated in this way, as a result of which gases are released in the still flowable carbon support material K and rise in the form of gas bubbles G in the carbon support material K counter to the effective direction SR of gravity. The space liberated by the decomposition processes in the carbon carrier material K is replaced by the carbon carrier material column present in the interior 3 of the container 2 , which automatically follows as a result of the effect of gravity. This process continues until the partial volume heated by the heating device 10 in the heating zone it generates has completely carbonized in the technical sense and has assumed a solid form. Since all of the cavities vacated by the gas formation have each been filled directly by the flowable carbon support material K pushing in behind, the density of the partial volume of the carbon support material K coked in this way is at least 1.4 g/cm ³ .

The detachment of the gas bubbles G from the carbon carrier material K is mechanically assisted on the one hand by the vibrations that are induced in the carbon carrier material K via the device 16 . On the other hand, the gas bubbles G are removed from the carbon carrier material K promoted in that a negative pressure is maintained via the suction tube 8 in the interior 3 of the container 2, which can reach to the vacuum.

Since the carbonization starts from the sides of the inner space due to symmetric heating, the carbonization proceeds from the outside to the inside. During coking of the outer layer, liquid, initially low-viscosity carbon carrier material K is present both in the core area and in the layer above it, through which the gas bubbles G can escape and possible pores are thus closed. This allows for a high density of the coke product obtained. During coking of the core area, carbon carrier material K can flow from the layer above. Here, too, the pores are closed.

Should small gas bubbles nevertheless be trapped in the core area KB of the coke product VK, this has only a minor effect on the mechanical properties, since the neutral axis of the respective columnar coke product VK runs along the relevant core area and this area is therefore not exposed to increased tensile forces during use. or compressive stresses.

After the partial volume of the carbon carrier material K adjoining the base element 9 has coked, the heating device 10, which is still in the heating mode, and with it the vibration device 16, which is also still active, are moved by means of the actuating device 13 against the effective direction SR of gravity by means of the linear drive 15 in a continuous movement along the linear guide 14 in the direction of the upper end of the container 2.

The speed of the upward movement of the heating device 10 and the vibration device 16 coupled to it is dimensioned in such a way that the heating zone generated by the heating device 10 is in each case in the effective range located partial volume of the carbon carrier material K is gradually heated and then kept over a coking time at the respective coking temperature, which is sufficient for complete coking in the technical sense and the associated full solidification. In practice, conveying speeds of the heating device 10 are typically in the range of 0.025-1.5 m/h, in particular 0.05-0.5 m/h.

The movement of the heating device 10 is continued until the upper section of the carbon substrate K adjoining the mirror SK of the carbon substrate K is also coked. The level SK of the carbon carrier material K has dropped due to the gas that has escaped from the carbon carrier material K and the associated loss of volume compared to the state when the interior 3 of the container 2 was refilled.

After the upper area BP of the carbon carrier material K adjoining the mirror SK has also coked and assumed a solid form, the container 2 is opened and the coking product VK formed in its interior 3 is removed from the interior 3 . The liner or sliding layer 5 present on the inner space 3 of the container 2 makes it easier to remove the coke product VK.

If it turns out that the required density of at least 1.4 g/cm ³ was not achieved in the upper area BP of the carbonization product VK because there was no longer sufficient free-flowing carbon carrier material K available during the carbonization to Gas bubbles G to fill cavities left behind, the relevant area BP is separated. It can be reused by grinding it into fine particles, which are added to the carbon support material K as solid carbon components can be provided for the production of further carbonization products VK in the device 1.

The carbonization product VK obtained in this way is subjected to a customary graphitization process to produce a graphite electrode, as is required in an electric steelworks, in order to give it a graphitic structure. Due to the monolithic, near-net shape geometry already obtained with the device 1 in the manner described above after the first coking, the grinding, mixing and shaping processes customary in the conventional method are just as obsolete as the associated first firing. Depending on the density of the product, the impregnation step can be omitted. If it turns out that the density of the coking product VK obtained is not sufficient, prior to the further processing of the coking product VK into the graphite product, i.e. into the graphite electrode, impregnation can also be carried out in a conventional manner to increase the density.

The in the Figures 2a - 2d The device 101 shown for producing a coking product VK corresponds in its construction to that in FIGS Figures 1a - 1d shown device 1 with the difference that in the device 101 instead of the device 1 provided fixed filling tube 7 a lance-like insertable into the interior 3 of the container 2 of the device 101 and removable filling tube 107 is provided. The maximum insertion length of the filling tube 107 is dimensioned such that the filling tube 107, when fully inserted into the interior 3, ends just above the height H10 over which the heating zone generated by the heating device 10 extends in the starting position of the heating device 10 ( Fig: 2a ). In this way, negative effects of splashes that can be released during the coking process are avoided.

In order to produce a columnar coke product VK, the interior 3 of the container 2 is filled with the device 101 via the filling tube 107 filled with a partial volume of flowable carbon carrier material K until the level SK of the carbon carrier material K contained in the interior space 3 ends above the height H10 over which the heating zone generated by the heating device 10 in its starting position extends ( Figure 2a ).

This partial volume of the carbon carrier material K, which forms the lower section of the coking product VK to be produced, is then brought to the coking temperature in a stepwise and controlled manner for the device 1 .

With the onset of coking, further flowable carbon carrier material K, which has been preheated for liquefaction if necessary, is fed in quasi-continuously via the filling pipe 107, which has been raised by a corresponding amount, and the heating device 10 with the vibration device 16 coupled to it by means of the actuating device 13 in the for the device 1 moves along the container 2 already described manner. The movement of the filling tube 107, which is height-adjustable via an adjusting device not shown here, and the heating device 10 are coordinated with one another in such a way that the vertical distance between the heating device 10 and the free end of the filling tube 107 protruding into the carbon carrier material K remains constant. The free end of the filling tube 107 always remains close to the level SK of the carbon carrier material K filled in the container, until the maximum filling level in the container 2 is reached.

The height of the level SK of the carbon carrier material K is maintained in such a way that there is always a sufficient quantity of free-flowing carbon carrier material K available above the partial volume of the carbon carrier material K in the coking process in order to fill the cavities left behind by the gas bubbles G. which exit from the partial volume of the carbon support material K which has been heated to the coking temperature and is kept at the coking temperature. The way, The distance that the gas bubbles G have to cover through the liquid carbon carrier material K is shorter than in the device 1, so that an even further optimized density of the coke product VK can be achieved.

In figure 3 a device 201 for the production of a coke product VK is shown, in which, in contrast to the devices 1 and 101, a heating device 210 provided on the device 201 is stationary, i.e. stationary during operation, whereas the carbon carrier material K to be coked moves along the heating device 210 and is coked on this path along the heating device 210 to form a solid coking product VK, which is continuously withdrawn from the device 201 in the manner of a continuous casting process.

For this purpose, the device 201 has a container 202 which delimits an interior space 3 which, like the interior spaces 3 of the devices 1 , 101 , widens in a funnel shape in an upper area and is closed off by a cover 206 . As in the case of the covers 6 of the devices 1, 101, a suction tube 208 and a filling tube 207 arranged in the manner of the filling tube 7 of the device 1 are guided through the cover 206 here.

The cylindrical area 217 of the interior space 203 arranged under the funnel-shaped upper area is open at the bottom in the manner of a chill mold and is significantly shorter than in the devices 1, 101. The section of the container 202 surrounding the area 217 sits in the annular heating device 210, which extends over a significant part of the height of area 217. The heating coils 211 of the heating device 210 can be regulated segment by segment in order to enable an optimal temperature profile in the partial volume of the carbon carrier material K located in the effective area of the heating zone generated by the heating device 10.

To produce a coking product VK, the lower outlet opening of the mold-like area 217 of the interior 203 is first closed with a stopper and a first partial volume of carbon carrier material K is filled into the interior 203 of the container 202 via the filling tube 207 .

The carbon carrier material K located in the active area of the heating zone generated by the heating device 210 is gradually controlled by means of the stationary heating device 210, heated to the coking temperature and held there until it is completely coked in the technical sense and has assumed a solid form.

In the course of the coking process, the carbon carrier material K coked in this way is continuously pulled out of the mold-like region 217 of the interior 203 of the container 202 by means of the stopper via its lower opening as a strand. At the same time, new, possibly preheated carbon carrier material K is also continuously filled into the container 202 via the filling pipe 207 . The lower opening area 218 of the area 217 can widen in the shape of a funnel in the direction of gravity SR in order to make it easier to pull out the coke product VK in the form of a strand. The pull-out forces are dimensioned in such a way that the coke product is continuously pulled out of the container 202 despite the negative pressure/vacuum present in the container 202 above the carbon carrier material filled in it.

The process of drawing off and refilling takes place synchronously with one another so slowly that the dwell time for which the carbon carrier material K passing the heating device 210 is kept at the coking temperature corresponds to the coking time required for its technically complete coking.

As in the case of the device 101, the level of the mirror SK of the flowable carbon support material K is already above that as a result of the Coking solidified carbon carrier material K adjusted so that on the one hand the gas bubbles G, which emerge from the carbon carrier material K in the coking process, only have to cover a short distance through the flowable carbon carrier material K until, after exiting the carbon carrier material K, they are sucked off via the suction pipe 208 on the other hand, there is always a sufficient amount of liquid carbon carrier material K available to fill the pores left behind by the gas bubbles G through liquid carbon carrier material K pushing into the solidifying carbon carrier material K. Also with a device of the in 3 The type shown can thus produce optimally dense coking products with an optimally homogeneous distribution of properties.

The outgassing of the gas bubbles G can be assisted by a vibration device 216 which, as in the devices 1.101, is arranged above the heating device 210, but here, corresponding to the fixed arrangement of the heating device 210, is stationary. As already mentioned, the container 202, which functions in the manner of a mold, can also be subjected to a negative pressure/vacuum in the area above the carbon carrier material K filled in it in order to prevent the gases G formed in the coking process from outgassing from the carbon carrier material K in the container 202 support.

After exiting the container 202, the coking product VK drawn off continuously from the device 201 as a strand passes through a cooling section 219 in which it is cooled to room temperature at an accelerated rate. Then, in a cutting-to-length device 220, coking products VK with the respectively desired length are cut off from the strand in a manner known per se.

As in the case of continuous casting of molten metal, a central distributor, not shown here, which includes the chill-like container areas 217 Carbon carrier material K feeds, two or more such mold-like container areas 217, each with a heating device 210 arranged thereon and a vibration device 216 also mounted thereon, can be provided in order to achieve maximum productivity.

Figure 4a shows a device 301 for producing a coking product VK in a method not according to the invention, which comprises a pot-shaped container 302 made of a suitable steel material, which is closed by a cover 306. A suction tube 308 is guided through the cover 306 and is connected to a suction device (not shown here) for evacuating the interior space 303 surrounded by the container 302 . The container 302 sits in a heating device 310, the stationary, annular heating coil 311 of which extends over the entire height of the container 302, so that the heating device 310 can generate a heating zone corresponding to the entire height of the container 302.

For the production of a block-shaped carbonization product VK ( Figure 4b ) the lid 306 is removed from the container 302 and flowable carbon carrier material K is filled into the interior 303 of the container 302 . The container 302 is then closed by putting on the lid 306 and the carbon carrier material K contained in the container 302 is brought to a coking temperature of 450-900.degree. When the coking temperature is reached, the coking and solidification of the carbon carrier material K begins from the lateral inner surfaces of the interior 303. The core area KB of the carbon carrier material K remains highly fluid over a long period of time, so that gas bubbles G that get there, such as those from the Coking located partial volumes of the carbon support material K exiting gas bubbles G, move against gravity in the direction of the mirror SK of the carbon support material K contained in the container for a long time.

If the coking process has progressed so far that the core area KB is also coked up, it can happen that smaller gas bubbles G are trapped in the inner core area KB. However, the resulting porosity there is harmless, since coking products of the type produced in the device 301 are usually used for applications in which the highest demands are placed on conductivity and stability, particularly in the area of the outer edge sections of the coking product VK, while the quality of the core area KB only plays a subordinate role. Such requirement profiles arise, for example, in plants for the production of aluminum when coking products VK of the type produced according to the invention are to be used there as anodes or cathodes, in particular as anodes.

The flowable carbon carrier material K used in the devices 1, 101, 201, 301 for the production of the respective coking product VK consists of products obtained during the distillation of petroleum products and the utilization of coal, such as tars and their derivatives, pitch, flowable bitumen, resins and products from the processing of biomass, such as cellulosic products, sugar and starch, or other products that can be coked. This carbon support material K is optionally with granular coke or graphite with a maximum grain size of 10 mm and optionally one or more additives such as iron oxide to reduce the puffing effect, a boron source such as boron carbide to reduce the thermal expansion coefficient or to improve the generated Crystal structure, or carbon or graphite fibers, which contribute to improving the mechanical properties and also to reducing the coefficient of thermal expansion. The carbon carrier material K used in each case is liquid at the process temperature in such a way that it flows under the action of gravity into the interior space 3 , 103 , 203 , 303 bounded by the container 2 , 102 , 202 , 302 .

REFERENCE MARKS

• figures 1 , 2

  1

  contraption

  2

  Device 1 container

  3

  Interior of the container 2

  4

  upper section of interior 3

  5

  sliding layer

  6

  Lid of the container 2

  7

  filling pipe (filling opening)

  8th

  suction pipe

  9

  floor element

  10

  heating device

  11

  Heating coil of the heating device 10

  12

  Outer surface of the container 2

  13

  adjusting device

  14

  Linear guide of the adjusting device 13

  15

  Linear drive actuator 13

  16

  vibration device

  101

  Device for the production of a coke product

  107

  filling tube

  bp

  Area of the carbon carrier material K adjoining the mirror SK

  H10

  Height of heater 10

  H3

  Interior height 3

• figure 3

  201

  Apparatus for making a coke product

  202

  container designed in the manner of a mould

  203

  Interior of the container 202 designed in the manner of a permanent mold

  206

  lid

  207

  filling pipe (filling opening)

  208

  suction pipe

  210

  heating device

  211

  Heating coil of the heating device 210

  216

  vibration device

  217

  Lower cylindrical area of the interior 203 of the container 202, which is open at the bottom

  218

  lower funnel-shaped expanded opening area of area 217

  219

  cooling line

  220

  cutting device

• Figures 4a, 4b

  301

  Device for producing a coke product VK

  302

  container

  303

  Interior of the container 302

  306

  lid

  308

  suction pipe

  310

  heating device

  311

  Heating coil of the heating device 310

  KB

  Core area of the carbon support material K

• General

  G

  gas bubbles

  K

  flowable carbon support material

  L

  Longitudinal axis of the device 1

  SR

  direction of gravity

  SK

  Level of the carbon carrier material K contained in the interior 3 of the container 2, 202, 302

  V

  vertical direction

  VK

  carbonization product

Claims (10)

1. Method for producing a coking product (VK) formed by solidification of a carbon carrier material and intended for use in the production of metals, metal alloys and metallurgical products or as an intermediate product for the production of graphite elements, and having a near-net-shape, monolithic geometry and a density of at least 1.4 g/cm³, the method comprising the following work steps:

   a) providing a container (2, 202) which

   - delimits an interior (3) and comprises

   - a filling opening for pouring a flowable carbon carrier material (K) into the interior (3) and

   - a heating device (10, 210) for heating the carbon carrier material (K) poured into the interior (3) of the container (2, 202);

   b) introducing the flowable or pourable carbon carrier material (K) via the filling opening into the interior (3) of the container (2, 202), wherein the carbon carrier material (K) has at least one liquid or meltable, carbonizable carbon component and optionally at least one solid carbonizable carbon component and also optionally at least one additive, which serves to adjust the properties of the carbon carrier material (K);

   c) heating the carbon carrier material (K) poured into the interior (3) of the container (2, 202) to a coking temperature by means of the heating device (10, 210), wherein the carbon carrier material (K) heated to the particular coking temperature is held at the coking temperature until the carbon carrier material (K) held at the coking temperature is solidified by coking to form the coking product (VK),

   - wherein during work step c) a relative movement takes place between the heated carbon carrier material (K) and the heating device (10, 210) along the longitudinal axis of the container (2, 202),

   - by the heat emitted by the heating device (10, 210) covering only a partial volume of the carbon carrier material (K) poured into the interior (3), which partial volume extends over a specific portion of the height of the interior (3) of the container (2, 202), and

   - either the carbon carrier material (K) poured into the interior (3) of the container (2, 202) is at a standstill while the heating zone (10, 210) is moved from the base, arranged at the bottom in the direction of gravity, counter to the direction of gravity in the direction of the upper end of the container (2, 202), or

   - the heating device is stationary and the carbon carrier material (K) poured into the container (2, 202) is moved relative to the heating device (10, 210) either by moving the container with the carbon carrier material poured therein along the fixed heating device or by a discharge opening being provided in the base of the container (202), via which discharge opening the coking product (VK) is continuously removed from the container (2, 202) as a strand formed from the solidified carbon carrier material (K) (work step e)); and

   d) wherein gas escaping from the carbon carrier material (K) during the heating and holding (work step c)) is discharged from the container (2, 202);

   e) removing the coking product (VK) from the container (2, 202).
2. Method according to claim 1, characterized in that the liquid or meltable carbon component of the carbon carrier material (K) consists of at least one component from the following group: "residues from the distillation of petroleum, products resulting from the processing of coal, tars and the derivatives thereof, pitch, flowable bitumen, resins and products from the processing of biomass, cellulose products, sugar and starch."
3. Method according to either of the preceding claims, characterized in that the carbon carrier material (K) contains a solid carbon component consisting of at least one component from the following group: "granular coke, coal, bitumen in solid form, lignites, anthracite coal, graphite, products from the recycling of carbon fibers."
4. Method according to any of the preceding claims, characterized in that the carbon carrier material (K) contains an additive from the following group: "iron oxide, titanium oxide, boron and boron compounds."
5. Method according to any of the preceding claims, characterized in that the heating of the carbon carrier material (K) (work step c)) begins only after the filling of the carbon carrier material (K) (work step b)) has been completed.
6. Method according to any of claims 1-4, characterized in that the heating of the carbon carrier material (K) (work step c)) begins while the carbon carrier material (K) (work step b)) is being poured into the interior (3).
7. Method according to any of the preceding claims, characterized in that the coking temperature in work step c) is 450-900°C.
8. Method according to any of the preceding claims, characterized in that the coking time in work step c) is up to 96 hours.
9. Method according to any of the preceding claims, characterized in that the atmosphere in the interior (3) of the container (2, 202, 302) is evacuated in order to forcibly discharge (work step d)) the gas escaping out of the container (2, 202) from the carbon carrier material (K) heated to the coking temperature.
10. Method according to any of the preceding claims, characterized in that the carbon carrier material (K) inside the container (2, 202) is set in motion at least occasionally.

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