Method, dryer device, battery recycling system and open-loop and / or closed-loop control unit

Abstract

The invention relates to a method for drying at least one battery material using a dryer device (10), in particular an industrial dryer device (12), comprising at least the following steps: drying (100) the battery material in a low-temperature region and / or low-pressure region, wherein, in at least one drying step (120), low boilers are removed from the battery material, wherein, in at least one further drying step (122), high boilers are removed from the battery material.

Description

[0001] Method, drying device, battery recycling system and control and / or regulating unit

[0002] State of the art

[0003] The invention relates to a method for drying at least one battery material according to claim 1, a drying device according to claim 9, a battery recycling system according to claim 12 and a control and / or regulating unit according to claim 14.

[0004] A method for drying batteries has already been proposed in EP 3289627 B1, in which both the low-boiling and high-boiling components are removed in a drying step in the low-temperature and low-pressure range.

[0005] The object of the invention is, in particular, to provide a generic method with advantageous properties with regard to drying efficiency. This object is achieved according to the invention by the features of claim 1, while advantageous embodiments and further developments of the invention can be found in the dependent claims.

[0006] Advantages of the invention

[0007] A method for drying at least one battery material using a drying device, in particular an industrial drying device, is described, comprising at least the following steps:

[0008] Drying the battery material in a low-temperature and / or low-pressure range, wherein in at least one drying step low-boiling substances are removed from the battery material, and wherein in at least one further drying step high-boiling substances are removed from the battery material, is proposed.

[0009] Such a process can advantageously increase drying efficiency, as optimal drying conditions for low-boiling and high-boiling substances can be provided in each drying step. This allows for a reduction in drying time. Particularly advantageous is the further improvement of the cost-effectiveness of drying battery materials. Furthermore, the scalability of the drying process, especially in industrial applications, can be improved by separating the drying steps for low-boiling and high-boiling substances. Additionally, drying in the low-temperature and / or low-pressure range can advantageously improve the durability of the drying equipment and, in particular, a battery recycling system, by largely preventing the formation of hazardous substances during drying, especially hydrogen fluoride.Furthermore, drying can advantageously remove so much electrolyte from the battery material that an electrochemical reaction is no longer possible or only possible to a negligible extent.

[0010] The process is specifically for drying battery material for recycling batteries, particularly accumulators. Specifically, the battery material is a battery and / or at least a part of a battery, particularly an accumulator and / or a part of an accumulator, which is used in particular in the manufacture or assembly of batteries, preferably including the parts and materials that arise as rejects during the manufacturing process. Furthermore, the term "battery material" includes all material resulting from the recycling process, in particular the material produced by crushing batteries. "At least one" battery material is understood to mean, in particular, the material of at least one battery, or preferably, the material of a plurality of batteries.Preferably, the method for drying battery material comprises all batteries suitable for recycling and / or inactivation, such as lead-acid batteries, nickel-cadmium batteries, nickel-metal hydride batteries, sodium-ion batteries, and / or, particularly preferably, lithium-ion batteries. The drying step for drying the low-boiling components and the drying step for drying the high-boiling components are carried out using the drying device, for example, by vacuum drying, contact drying, convection drying, and / or radiation drying. The drying device includes a drying chamber into which the battery material is introduced for drying. Preferably, the drying chamber is hermetically sealed, at least for the drying of the battery material.The term "industrial drying device" shall be understood to mean, in particular, a drying device specifically designed for large-scale use in industrial processes. Specifically, the drying vessel has a capacity of at least 50 liters, preferably at least 200 liters, advantageously at least 1000 liters, particularly preferably at least 10,000 liters, and most advantageously at least 20,000 liters.

[0011] Preferably, drying is carried out under stirring and / or mixing, wherein the drying device has at least one agitator, in particular for mixing and / or granulating the battery material at least in the drying container, with at least one agitator with agitator blades, in particular at least two agitator blades, which are preferably connected to a motor-driven shaft, and which, in particular, are flat, agitator blades are arranged inclined upwards from the inside to the outside at an angle α, which is preferably in a range of about 15° to about 60°, wherein in particular at least one of the agitator blades is equipped at its inner end with a bottom blade forming a bottom scraper.Preferably, the drying vessel consists of an upper cylindrical part and an adjoining lower conical bottom part, the angle of which is particularly in the range of about 60° to about 120° and preferably substantially 90°. Preferably, the stirring blades are arranged at least substantially within the conical part of the drying vessel. In particular, the battery material is stirred by the stirring blades in the conical part of the drying vessel. This advantageously further improves the drying of the battery material.

[0012] In particular, the set temperature and / or pressure in the drying device, especially in the drying vessel, define drying parameters for removing the low-boiling and / or high-boiling elements. Specifically, in the drying step for removing the low-boiling elements and / or the drying step for removing the high-boiling elements, water is removed from the battery material. Preferably, the drying takes place in a low-temperature range at a temperature below the boiling point under standard conditions of at least one low-boiling element and / or one high-boiling element, preferably at least to a substantial extent below 200°C, advantageously at least to a substantial extent below 150°C, and particularly preferably at least to a substantial extent below 120°C. In particular, a low-pressure range is understood to mean a controlled vacuum.Preferably, drying takes place in the low-pressure range at a pressure below the vapor pressure of at least one low-boiling and / or high-boiling substance at the set temperature. In particular, a pressure of at least a substantial portion of a maximum of 500 hPa, preferably at least a substantial portion of at most 400 hPa, and most preferably at least a substantial portion of at most 350 hPa is used for drying in the low-temperature range.The term "at least to a substantial extent" shall be understood in particular to mean that at least 20%, preferably at least 50%, advantageously at least 75%, particularly preferably at least 90% of the drying step and / or process step are carried out with the corresponding parameters, wherein in particular the further proportion also includes a fall below and / or an exceedance of the value, and particularly advantageously the entire drying step and / or process step is carried out with the corresponding parameters.

[0013] In particular, during drying, the electrolyte content, especially the proportion of electrolyte solvent, in the battery material is reduced, and the battery material is inactivated, preferably until an electrochemical reaction is impossible. Preferably, after drying, the electrolyte content is below a threshold value, in particular at which the cell voltage has decreased to at most one-third, preferably to one-quarter. Preferably, the drying of the comminuted material is stopped when, after completion of the drying process, no flammable or explosive gas mixture can form above the battery material and / or when the battery material is so dry that it is at least substantially inert, in particular so that no flammable or explosive gas mixture can form during further processing.Preferably, the drying, in particular the drying steps for removing the low and high boiling points, is carried out until the electrolyte content is at most 6 wt.%, preferably at most 4 wt.%, advantageously at most 3 wt.% and particularly preferably at most 2 wt.%.

[0014] Preferably, during the drying step to remove the low-boiling components, the portions of the battery material containing easily volatile components, which have a boiling point below 150 °C, particularly under standard conditions, are removed, wherein preferably the proportion of the low-boiling components remaining after the drying step is at most 6 vol%, more preferably at most 4 vol%, and most preferably at most 3 vol%. Low-boiling components, particularly in lithium-ion batteries, are, for example, solvents such as dimethyl carbonate (DMC) and / or ethyl methyl carbonate (EMC).

[0015] Preferably, during the drying step to remove high-boiling components, the portions of the battery material containing components that are difficult to vaporize and which, particularly under standard conditions, have a boiling point above 150 °C, are removed. Preferably, the proportion of high-boiling components remaining after the drying step is at most 6 vol%, more preferably at most 3 vol%, advantageously at most 1 vol%, and most preferably at most 0.5 vol%. Examples of high-boiling components are organic electrolytes such as ethylene carbonate (EC) and / or propylene carbonate (PC), and / or additives such as cyclohexylbenzene and / or various flame retardants.

[0016] Preferably, the drying step for removing the low-boiling components is carried out, in particular immediately, before the drying step for removing the high-boiling components, and preferably after the drying step for removing the low-boiling components has been completed. In particular, the drying step for removing the low-boiling components and / or high-boiling components is carried out under drying parameters that are specifically adjusted to remove the low-boiling components and / or high-boiling components. In particular, the drying parameters are adjusted during the transition from the drying step for removing the low-boiling components to the drying step for removing the high-boiling components.

[0017] Alternatively, it is conceivable that the drying step for removing the low-boiling substances overlaps at least partially with the drying step for removing the high-boiling substances, wherein, in particular, at most 80%, preferably at most 50%, and most preferably at most 20% of the drying step for removing the low-boiling substances overlaps with the drying step for removing the high-boiling substances, and / or, in particular, at most 80%, preferably at most 50%, and most preferably at most 20% of the drying step for removing the high-boiling substances overlaps with the drying step for removing the low-boiling substances. Preferably, during the overlap of the drying steps for removing the low-boiling substances and for removing the high-boiling substances, drying parameters, in particular a low-temperature range and / or a low-pressure range, are set under which the removal of the low-boiling substances and the high-boiling substances takes place.

[0018] Preferably, in at least one further process step, the battery material is comminuted, preferably providing the comminuted material to separate, for example, cathode and anode materials, separators, and electrolytes. In principle, it is conceivable that the process step for comminuting the battery material takes place after drying the battery material. Particularly preferably, the process step for comminuting the battery material takes place, preferably immediately, before drying the battery material. Preferably, the comminution in this process step is carried out using shear, impact, and collision forces to ensure efficient separation of the materials and to prepare the comminuted material for subsequent sieving.Preferably, the shredded battery material is passed through at least one sieve, and in particular several sieves with different mesh sizes, of the shredding device, which is preferably arranged below a shredding shaft of the shredding device. The sieve is preferably provided for this purpose.

[0019] Preferably, in a further process step, advantageously after drying the battery material in a low-temperature and / or low-pressure environment, high-temperature drying is carried out. In particular, the high-temperature drying is intended to decompose a binder, for example, consisting of polyvinylidene fluoride, polytetrafluoroethylene, carboxymethylcellulose, styrene-butadiene rubber, and / or another material suitable for the respective battery material. Preferably, the high-temperature drying is carried out at a drying temperature and for a drying duration selected such that the binder, which binds the active material of the lithium battery to a support, decomposes at least predominantly.The decomposition temperature is understood in particular to be the lowest temperature at which, after holding the battery material at this temperature for one hour, at least 80 percent by mass of the binder has decomposed into gaseous components, in particular at least to a substantial extent at a temperature of at least 200 °C, preferably at least to a substantial extent at a temperature between 200°C and 500°C.

[0020] Furthermore, it is proposed that the drying step for removing the low-boiling elements and the drying step for removing the high-boiling elements be carried out in a single drying chamber of the drying device and / or in batch operation. This advantageously allows for precise control of the drying parameters for each batch of battery material, resulting in a more uniform and reliable removal of low-boiling and high-boiling elements. Costs can also be reduced, as maintenance is advantageously simpler and energy consumption is lowered. Specifically, a single drying chamber is understood to be a drying space bounded by an outer wall, which may, in particular, have several drying chambers; however, preferably the drying chamber has only one receiving chamber for drying the battery material.The battery material is preferably fed from a bunker into the drying device, with the battery material for batch operation being advantageously stored in the bunker.

[0021] In an alternative embodiment of the invention, drying takes place in at least two drying containers of the drying device and / or in continuous operation. In particular, the removal of the low-boiling components is carried out in at least a first drying container or in a first part of the drying container, and the removal of the high-boiling components is carried out in at least a second drying container or in a second part of the drying container. In particular, the battery material is continuously fed to and removed from the drying device. In continuous operation, with only one drying container, the battery material is continuously passed through several drying chambers within the drying container.

[0022] It is further proposed that the drying step for removing the high-boiling components be carried out at a higher temperature than the drying step for removing the low-boiling components. By adjusting the drying temperatures to the specific boiling points of the low-boiling and high-boiling components, a more precise and effective removal of the various components can advantageously be achieved. In particular, the formation of hydrogen fluoride can be advantageously prevented, at least substantially, and the high-boiling components can be removed as efficiently as possible. Specifically, the temperature is increased from the drying step for removing the low-boiling components to the drying step for removing the high-boiling components. Preferably, the transition between the drying step for removing the low-boiling components and the drying step for removing the high-boiling components is achieved by controlled self-heating of the battery material.Preferably, after the drying step to remove the low-boiling substances, further thermal energy is supplied, which is set to evaporate the low-boiling substances, so that, in particular due to the higher boiling point of the high-boiling substances, the battery material heats up further, preferably until the high-boiling substances evaporate at these higher temperatures.

[0023] Alternatively, the temperature, and in particular the supply of thermal energy, is actively controlled, especially during the transition between the drying step for removing the low-boiling components and the drying step for removing the high-boiling components. This could be done, for example, to accelerate the heating of the battery material to the temperature required for removing the high-boiling components. In particular, it is conceivable that the temperature, and especially the supply of thermal energy, is increased prematurely. This can advantageously accelerate the drying process. Alternatively, it is conceivable that the supply of thermal energy is initially reduced after the drying step for removing the low-boiling components, so that the temperature in the drying step for removing the high-boiling components is initially constant compared to the temperature in the drying step for removing the low-boiling components.This allows for a further advantageous reduction in the proportion of low-boiling substances and the water content of the battery material, while also ensuring that the formation of hydrogen fluoride during heating is prevented. Premature or delayed heating leads to an overlap of the drying steps required to remove the low-boiling and high-boiling substances.

[0024] Furthermore, it is proposed that in the drying step for removing the high-boiling components, the drying process be carried out at least to a substantial extent at a temperature of at least 80 °C. This advantageously ensures that the high-boiling components evaporate efficiently. Moreover, the two separate drying stages can advantageously reduce the required vacuum level in industrial dryers with numerous sealing points and openings, as the temperature, particularly for the high-boiling components, is adjusted. Specifically, the removal of the high-boiling components is carried out at a temperature at least to a substantial extent between 80 °C and 150 °C, preferably at least to a substantial extent between 80 °C and 120 °C, and most preferably at least to a substantial extent between 80 °C and 110 °C.Furthermore, investigations have shown that a temperature range between 100 °C and 120 °C is advantageous for removing the high-boiling components, at least to a significant extent. Preferably, the battery material is dried in the drying step for removing the high-boiling components at least approximately and to a significant extent at a constant temperature profile, in particular at a constant temperature of at least 80 °C. An at least approximately constant temperature profile is understood to mean, in particular, a deviation, in particular a temperature fluctuation, of at most 20%, preferably 10%, advantageously 5%, and most preferably 1%. In a further embodiment of the invention, the battery material is dried in the drying step for removing the high-boiling components using a multi-stage temperature profile, wherein, in particular, different temperatures are set for different high-boiling components.

[0025] Furthermore, it is proposed that in the drying step for removing the low-boiling components, the drying process be carried out at least to a substantial extent at a temperature of no more than 80 °C. This advantageously minimizes the risk of the formation of hazardous gases, particularly hydrogen fluoride, which arises especially when fluorine-containing compounds decompose at higher temperatures. Preferably, in the drying step for removing the low-boiling components, the battery material is dried at least approximately and to a substantial extent at a constant temperature profile, particularly at a constant temperature of no more than 80 °C. In a further embodiment of the invention, the battery material is dried in the drying step for removing the low-boiling components using a multi-stage temperature profile, with different temperatures being set for different high-boiling components.Furthermore, it is proposed that the pressure in the drying step for removing the high-boiling substances be set lower than in the drying step for removing the low-boiling substances. This advantageously lowers the evaporation temperature of the high-boiling substances, thus increasing the efficiency of the drying process. Furthermore, the formation of undesirable byproducts such as hydrogen fluoride can be advantageously avoided, at least substantially, during the removal of the high-boiling substances. In particular, the pressure is reduced from the drying step for removing the low-boiling substances to the drying step for removing the high-boiling substances. Specifically, in the drying step for removing the low-boiling substances, drying takes place at least to a substantial extent at a pressure of at least 100 hPa, preferably at least 200 hPa, advantageously at least 250 hPa, and particularly preferably at least 300 hPa.In particular, during the drying step for removing the high-boiling components, drying is carried out, at least to a substantial extent, at a pressure of no more than 300 hPa, preferably no more than 250 hPa, advantageously no more than 200 hPa, particularly preferably no more than 100 hPa, and most advantageously no more than 50 hPa. Preferably, the pressure is adjusted using a vacuum unit.

[0026] Furthermore, it is proposed that a fluid generated during the drying step for removing low-boiling substances and / or during the drying step for removing high-boiling substances be purified by a cleaning unit, particularly to remove at least hydrogen fluoride. This advantageously allows for more flexible temperature and / or pressure adjustment, as the release of hazardous substances such as hydrogen fluoride into other system components or the environment is at least substantially prevented. Specifically, the fluid, particularly the exhaust gas from the drying process, is purified by the cleaning unit located between the drying vessel and the vacuum unit.Preferably, the fluid is cleaned by a cleaning unit designed as a filter, in particular an activated carbon filter and / or a filter containing substances that react with hydrogen fluoride, and / or a cleaning unit designed as a gas scrubber, wherein the hydrogen fluoride is preferably absorbed from the fluid into a scrubbing liquid. In particular, the cleaning unit designed as a gas scrubber can advantageously prevent the release of hydrogen fluoride to a large extent, even when larger quantities are generated. Furthermore, it is proposed that after at least one drying cycle, the at least one drying container can be cleaned and / or maintained by opening a closure unit of at least one drying container. This allows for the advantageous regular cleaning and maintenance of the drying container, which improves the efficiency and reliability of the drying process.Furthermore, it is advantageous to set a lower vacuum in the drying chamber during the drying step for removing the high-boiling components at a temperature above 80 °C. This allows for multiple sealing points in the drying device, particularly on the drying chamber. In particular, a drying cycle includes at least drying the battery material in the low-temperature and / or low-pressure range. Preferably, the drying chamber requires maintenance and / or cleaning after a plurality of drying cycles, in particular at least two, preferably at least five, advantageously at least 10, and most preferably at least 100. In particular, the sealing unit is sealed with a gasket. Preferably, a pressure is set during the drying step for removing the high-boiling components, which is then sealed by the gasket.

[0027] Preferably, the dryer device, in particular the drying container, has further sealing points, such as an inlet and outlet opening for the battery material, safety valves and further valves, gas lines, rinsing lines and a shaft access for the stirring device.

[0028] Furthermore, it is proposed that during a pressure reduction phase into the low-pressure range, the exhaust gases be routed around a scrubber via a bypass and / or that the pressure reduction into the low-pressure range be achieved over a longer period. This advantageously avoids overloading downstream cleaning and safety devices, particularly a scrubber, thus enabling a more compact and economical design of these components. The exhaust gases are preferably routed via an adjustable bypass line with a controllable bypass valve, so that during the initial pressure reduction phase, the exhaust gases are routed around the scrubber and, in particular, directly subjected to thermal oxidation. Alternatively or additionally, it is proposed that the pressure reduction into the low-pressure range be achieved via an extendable pressure ramp.The ramp-up time for reaching the low-pressure range for removing the low-boiling substances is preferably extended by at least 50%, and particularly preferably by at least 100%, compared to a direct pressure reduction. In particular, the pressure reduction takes place over at least 5 minutes, preferably over at least 10 minutes, and particularly preferably over at least 20 minutes. Furthermore, it is conceivable that the pressure reduction to the low-pressure range for removing the low-boiling substances occurs in several stages, with a stepwise reduction via intermediate pressures being particularly advantageous, for example, at an intermediate pressure between 400 hPa and 700 hPa, before a final pressure in the desired low-pressure range is reached. Pressure control is preferably achieved by the control unit using a speed-controlled vacuum unit and a pressure sensor.

[0029] Furthermore, it is proposed that, to reduce pressure loss in the dryer, an exhaust gas stream be filtered in multiple stages using a vapor filter unit and / or bypassed around at least one vapor filter element of the vapor filter unit. This advantageously prevents dust and aerosol loads generated during drying from successively accumulating on a single vapor filter element. In particular, it is provided that the exhaust gas stream is first passed over a first, preferably coarse-pored, vapor filter element, in which solid agglomerates and fiber fragments, especially with a mean particle diameter greater than 10 µm, are preferably separated. The coarse-pored vapor filter element is, for example, designed as a cyclone or screen candle with a nominal mesh size of, for example, 25 µm, preferably at least 10 µm.A further, fine-pored vapor filter element, for example a PTFE or sintered metal filter element, preferably with a pore size of less than 1 pm, is preferably installed downstream to retain remaining fine dust particles and condensing aerosols. In particular, the vapor filter unit is equipped with a switchable bypass that opens at a defined differential pressure, preferably more than 200 mbar, more preferably more than 100 mbar, and most preferably more than 50 mbar. Preferably, the valve is switched to bypass the exhaust gas flow based on continuous monitoring of the differential pressure by the control unit.Preferably, the bypass is designed such that it diverts the main exhaust gas flow only for the duration of a regeneration phase of the vapor filter unit, with the return to normal operation occurring automatically as soon as the differential pressure drops below a defined threshold value. Furthermore, it is conceivable that, in a multi-stage vapor filter unit, at least one of the vapor filter elements, particularly preferably the coarse-pored vapor filter element, is equipped with the bypass.

[0030] Furthermore, it is proposed that a defrosting unit of a condenser unit, in particular a pre-condenser of the condenser unit, prevents icing of high-boiling elements and / or defrosts existing ice formation. This advantageously ensures continuous and low-maintenance operation, especially in the case of process fluctuations or longer operating intervals. The condenser unit preferably incorporates solvent recovery. Preferably, the defrosting unit includes an integrated ice storage unit, which is thermally coupled to the heat exchanger of the pre-condenser and activated by a controlled heat input. Particularly preferably, the defrosting unit is controlled by the control unit of the dryer device, utilizing sensor data such as pressure losses, heat flow, or condensate return volumes.Alternatively or additionally, the icing can be thawed manually, in particular by short-term temperature increase or by temporarily diverting the exhaust gas flow via a maintenance bypass of the pre-condenser.

[0031] Furthermore, it is proposed that the battery material be fed into an intermediate storage device before drying. This advantageously enables controlled intermediate storage as well as inerting and homogenization of the battery material before the drying step. The intermediate storage device is preferably arranged between the shredding device and the drying device. The battery material is preferably mixed in the intermediate storage device. Particularly preferably, the intermediate storage device is inerted, with nitrogen being supplied via at least one nitrogen line. The nitrogen line is preferably connected to a nitrogen supply unit, which is preferably provided for inerting the shredding device, the intermediate storage device, and / or the drying device.Nitrogen is preferably metered via valves, which in particular control the supply to the comminution device, the intermediate storage device, and / or the dryer. It is also proposed that the battery material be temperature-controlled in the intermediate storage device. This advantageously allows for faster and more controlled temperature control before the start of the drying process, thereby reducing the heating time of the dryer. Temperature control is preferably achieved by heating the intermediate storage device from the wall. The intermediate storage device is particularly preferably designed as a heated intermediate tank with a surrounding double jacket. Temperature control is particularly achieved below 80 °C, preferably in a temperature range between 40 °C and 80 °C, and most preferably in a temperature range between 60 °C and 70 °C.Particularly preferably, a portion of the low-boiling components is evaporated by tempering before the drying step in the dryer, preferably at a temperature that is below the decomposition temperature of halogen-containing conducting salts. Furthermore, tempering at a defined temperature preferably limits local temperature peaks in the battery material. It is also conceivable that the battery material is tempered using a heated shaft of the mixing unit.

[0032] It is further proposed that a negative pressure be established, at least partially, within the intermediate storage device. This advantageously allows for targeted pressure control within the intermediate storage device, thereby enabling the controlled discharge of gases and volatile components. The negative pressure is set, in particular, within a pressure range of -5 mbar to -100 mbar, and preferably between -5 mbar and -30 mbar, relative to ambient pressure. Particularly preferred is the continuous extraction of the gases located in the intermediate storage device, especially the supplied nitrogen, via a fan unit with at least one fan or blower. The fan unit is preferably designed such that the extracted gases are immediately subjected to thermal treatment.Particularly preferably, the exhaust gas is routed directly into a thermal oxidizer, which is also provided for the exhaust gas treatment of the dryer device and / or a comminution device.

[0033] Furthermore, a drying device, in particular an industrial drying device, for drying at least one battery material, in particular at least partially for carrying out the method, is proposed, comprising a vacuum unit and / or a heating unit, and a control and / or regulating unit, which is provided to regulate the vacuum unit and / or the heating unit in a low temperature range and / or low pressure range, wherein the control and / or regulating unit controls the vacuum unit and / or the heating unit in multiple stages during the drying of the battery material.

[0034] Such a drying device can advantageously increase drying efficiency when drying battery material, as it allows for the provision of optimal drying conditions for individual components in the battery material, particularly for the low-boiling and high-boiling components, in several stages. Furthermore, the scalability of the drying process, especially in industrial applications, can be improved due to the multiple stages. Additionally, drying in the low-temperature and / or low-pressure range can advantageously improve the durability of the drying device, particularly by preventing the formation of hazardous substances during drying, especially hydrogen fluoride. Specifically, the control unit is designed to control the heating unit and / or vacuum unit in multiple stages, depending on the components of the battery material to be removed.In particular, the control and / or regulating unit is designed to control at least two stages, especially the drying step for the removal of the low-boiling substances and the drying step for the removal of the high-boiling substances.

[0035] Furthermore, it is proposed that the drying device comprise at least one drying container in which a pressure can be set by means of the vacuum unit. This pressure unit has at least one closure unit, which is designed to be opened, at least substantially, for cleaning and / or maintenance of the drying container. This advantageously allows for regular cleaning and maintenance of the drying container, which in particular increases the efficiency and reliability of the drying process. Specifically, the closure unit is sealed by means of a gasket. Preferably, the heating unit is provided for setting a temperature in the drying container and / or the vacuum unit is provided for setting a pressure in the drying container.Furthermore, it is proposed that the dryer device includes at least one sensor unit designed to detect at least one drying parameter, in particular temperature, humidity, and / or gas composition, in the drying vessel, with the control unit performing multi-stage control based on the drying parameters. This advantageously provides optimized control of the drying parameters. In particular, the sensor unit is at least a temperature sensor element, a humidity sensor element, a pressure sensor element, and / or a gas composition sensor element. The sensor unit is especially preferably designed to detect at least one of the drying steps at the end, in particular the drying step for removing the low-boiling substances.Preferably, the sensor unit is designed to detect a temperature increase after the removal of the low-boiling substances, wherein the control and / or regulating unit controls at least the vacuum unit on the basis thereof, in particular the vacuum unit reduces a pressure in the drying container.

[0036] Furthermore, it is proposed that the vacuum unit be designed as a screw-displacement vacuum pump and / or rotary vane pump. This advantageously allows the low-pressure range with an absolute pressure of less than 20 mbar to be reached as efficiently as possible. Particularly preferred for maintaining the vacuum performance of the vacuum unit is the provision of, preferably regular, flushing of the screw-displacement vacuum pump and / or rotary vane pump, preferably with a suitable flushing medium.

[0037] Furthermore, it is proposed that at least the drying device, in particular the drying vessel and / or the solvent recovery of the drying device, be designed to be at least substantially resistant to halogenated hydrogen gases. This advantageously allows for high process reliability and plant availability, especially in the event of the potential release of corrosive decomposition products such as hydrogen fluoride during drying. Structural components of the drying device are preferably made of highly corrosion-resistant materials, such as Hastelloy C-276 or Hastelloy C-22. Heat exchangers within the solvent recovery system are preferably designed as graphite heat exchangers or lined with PTFE or PFA.Furthermore, seals are preferably made of FFKM elastomers, while in dynamically stressed areas, such as on vacuum pump shafts, metal bellows-encapsulated sealing systems are particularly used.

[0038] Furthermore, a battery recycling system is proposed, at least for carrying out the drying process of at least one type of battery material using a drying device. Such a battery recycling system can advantageously increase drying efficiency in the drying of battery material, as optimal drying conditions for the low-boiling and high-boiling components can be advantageously provided in each drying step. Moreover, the separation of the drying steps for low-boiling and high-boiling components can advantageously improve the scalability of the drying process and the battery recycling system, particularly in industrial applications.Furthermore, drying in the low-temperature and / or low-pressure range can advantageously improve the durability of the battery recycling system, particularly by preventing the formation of hazardous substances during drying, especially hydrogen fluoride. Specifically, the battery recycling system is a specialized facility for the environmentally sound and efficient recovery of valuable materials from used batteries and / or materials generated as waste during the battery manufacturing process, especially from lithium-ion batteries.

[0039] Furthermore, it is proposed that the battery recycling system includes a shredding unit designed to provide shredded battery material, with a drying unit designed to dry the shredded material. This advantageously ensures more efficient and uniform drying of the battery material. In particular, the shredding unit is designed to shred the battery material, especially subunits such as modules and / or stacks, and / or cells, for example, by means of at least one rotary shear, at least one rotor, and / or at least one cutting mill, preferably under a protective gas atmosphere.Furthermore, it is proposed that the battery recycling system includes at least one intermediate bunker device, wherein the intermediate bunker device has a fluid circuit for temperature control of the battery material, which is decoupled from the dryer device. This advantageously provides efficient and uniform thermal conditioning of the battery material before the drying step. The intermediate bunker device is preferably designed as a horizontally oriented pre-bunker, preferably with a horizontally arranged mixing unit. The mixing unit is particularly preferably equipped with at least one comb-blade agitator, preferably to ensure a uniform distribution of the battery material during filling. This advantageously avoids accumulations and uneven material distributions, thus enabling homogeneous feeding of the dryer device.The fluid circuit is preferably designed as a water circuit, which is particularly preferably routed within a jacketed heating element with a partition wall. Alternatively or additionally, the fluid circuit comprises a water-glycol mixture, a silicone oil, or a similar fluid. The water circuit is, in particular, hydraulically decoupled from the oil circuit of the dryer. Additionally or alternatively, the thermal contact is supported by a heated shaft. Temperature control is preferably achieved by a heating element, especially a heating element separate from the dryer, which is designed to heat the water circuit. In an alternative embodiment, a heat exchanger is provided that utilizes the residual heat from the oil circuit of the dryer to temperature control the water circuit.

[0040] Furthermore, it is proposed that the nominal volume of the intermediate storage device be at least a multiple of the nominal volume of the dryer. The nominal volume of the intermediate storage device is preferably at least 150% of the nominal volume of the dryer, and particularly preferably at least twice that. In particular, it is provided that the larger volume of the intermediate storage device allows for refilling of the dryer during an ongoing drying cycle. Preferably, any volume loss of the battery material due to drying within the first drying step is compensated for, whereby, after a defined time, such as after 20 minutes of drying time, or when a defined volume loss occurs, such as when the dryer's free volume reaches 20%, battery material is again fed from the intermediate storage device.In an alternative embodiment, the intermediate bunker device is designed as a central pre-bunker to which at least two dryer devices are assigned, preferably with parallel or alternating feeding of the dryer devices with battery material.

[0041] Furthermore, the control unit for carrying out the drying process of the at least one battery material is proposed to be integrated with the drying device, in particular at least partially with the drying device. The phrase "at least partially attributable to the drying device" is understood to mean, in particular, that the control unit is implemented at least partially externally, specifically on a local computer in a local network of the drying device and / or on an external computer, in particular in the cloud. Alternatively, the drying device may fully encompass the control unit.

[0042] The inventive method for drying battery material, the drying device, the battery recycling system, and the control and / or regulating unit are not limited to the application and embodiment described above. In particular, the inventive method for drying battery material, the drying device, the battery recycling system, and the control and / or regulating unit may, to achieve a functionality described herein, comprise a different number of individual elements, components, and units than the number specified herein. Furthermore, when specifying a number of an element, component, or unit using the term "at least," the minimum number should also be explicitly disclosed, in particular by a limitation with "only."

[0043] Drawings

[0044] Further advantages will become apparent from the following description of the drawings. The drawings illustrate an embodiment of the invention. The drawings, the description, and the claims contain numerous features in combination. A person skilled in the art will expediently consider the features individually and combine them into meaningful further combinations. The drawings show:

[0045] Fig. 1 shows a schematic representation of a battery recycling system, at least with a drying device.

[0046] Fig. 2 shows a schematic representation of the battery recycling system with an intermediate bunker device,

[0047] Fig. 3 shows a schematic representation of the dryer device with at least one control and / or regulating unit for regulating at least one heating unit and / or vacuum unit.

[0048] Fig. 4 shows a schematic representation of the dryer device with at least a vapor filter unit, a solvent recovery unit and a cleaning unit.

[0049] Fig. 5 shows a flowchart of a method for drying at least one battery material using the dryer device,

[0050] Fig. 6 shows a flowchart of a method for drying at least one battery material using the dryer device and

[0051] Fig. 7 shows a schematic temperature and pressure profile during the drying of at least one battery material with the dryer device.

[0052] Description of the exemplary embodiment

[0053] Figure 1 schematically shows a battery recycling system 90 with a drying device 10. The battery recycling system 90 is designed to carry out at least one method for drying at least one type of battery material using the drying device 10. The battery recycling system 90 is designed to recover valuable materials from used batteries. The battery recycling system 90 is designed to recover valuable materials from parts that are generated as rejects during a battery manufacturing process. The battery recycling system 90 is designed to at least partially recycle battery material. Preferably, the battery recycling system is designed for recycling lithium-ion batteries.

[0054] The battery recycling system 90 comprises at least one shredding device 14. The shredding device 14 is designed to provide the battery material for shredding. The shredding device 14 is designed to mechanically shred the battery material. The shredding device 14 is designed to shred the battery material using shear, impact, and / or collision forces. The shredded material is conveyed to the drying device 10. The battery recycling system 90 comprises a conveying system consisting of conveyor belts. The conveying system transports the shredded material from the shredding device 14 to the drying device 10. The drying device 10 is designed to dry the shredded material.

[0055] The battery recycling system 90 has a hopper (not shown) between the shredding device 14 and the drying device 10. The hopper collects the shredded material from the shredding device 14 before it reaches the drying device 10 to enable batch operation of the drying device 10.

[0056] The dryer 10 is an industrial dryer 12. The dryer 10 is specifically designed for large-scale use in industrial processes. The dryer 10 is designed as a vacuum dryer. The dryer 10 is intended for drying 100 of at least one battery material. The dryer 10 is at least partially intended for carrying out the process of drying the battery material.

[0057] The battery recycling system 90 includes at least one vacuum unit 20. The vacuum unit 20 is designed to remove the fluid produced during drying from the dryer 10. The vacuum unit 20 then passes the fluid produced during drying through a solvent recovery unit 16. The solvent recovery unit 16 is designed to adsorb the solvent dissolved in the fluid. The solvent recovery unit 16 includes distillation columns or condensers designed to condense the solvent. This recovery process allows the solvents to be regenerated and reused in the process, thus increasing the efficiency and sustainability of the battery recycling system 90.

[0058] The battery recycling system 90 has at least one recovery tank 22 for the solvent dissolved from the fluid produced during drying. The battery recycling system 90 has at least one cleaning unit 18. The vacuum unit 20 guides the fluid produced during drying through the cleaning unit 18. The cleaning unit 18 is connected downstream of the solvent recovery unit 16. The cleaning unit 18 is designed to remove hazardous substances from the fluid. The cleaning unit 18 is configured as a gas scrubber. The cleaning unit 18 is designed to remove hydrogen fluoride from the fluid produced during drying. The battery recycling system 90 has at least one outlet 24. The fluid produced during drying is discharged from the battery recycling system 90 through the outlet 24 after the cleaning unit 18.

[0059] The battery recycling system 90 has at least one storage container 26 for storing the dried battery material. The storage container 26 for the dried battery material is located downstream of the drying device 10. The storage container 26 for the dried battery material is designed to receive the battery material after drying. The storage container 26 is, for example, designed as a container in which the battery material can be stored airtight.

[0060] Figure 2 shows the battery recycling system 90 with an intermediate storage device 32. The battery recycling system 90 includes at least the intermediate storage device 32. The intermediate storage device 32 is arranged between the shredding device 14 and a drying device 10. The intermediate storage device 32 is designed to temporarily store a defined quantity of battery material.

[0061] The intermediate storage device 32 is designed as a horizontally oriented pre-storage hopper. The intermediate storage device 32 includes a mixing unit 34. The mixing unit 34 is designed at least substantially horizontally. The mixing unit 34 includes at least one comb-blade agitator. The nominal volume of the intermediate storage device 32 is at least a multiple of the nominal volume of the dryer 10. The nominal volume of the intermediate storage device 32 is at least 150% of the nominal volume of the dryer 10.

[0062] The intermediate bunker device 32 has a heating unit 52.

[0063] The intermediate storage device 32 has a fluid circuit, decoupled from the dryer device 10, for temperature control of the battery material. The heating unit 52 includes the fluid circuit. The intermediate storage device 32 has a fluid circuit, decoupled from the dryer device 10, for temperature control of the battery material. The fluid circuit is designed as a water circuit. The fluid circuit is guided in a jacket heater 54 with a partition wall. The water circuit is hydraulically decoupled from an oil circuit of the dryer device 10. Temperature control is achieved by a heating element 56, which is provided for heating the water circuit.

[0064] The intermediate storage device 32 has at least one fan unit 58. The fan unit 58 is designed for the continuous extraction of the nitrogen supplied to the intermediate storage device 32. The fan unit 58 is configured such that the extracted gases are immediately subjected to thermal treatment. The exhaust gas is routed directly to a thermal oxidizer 36, which is additionally provided for the exhaust gas treatment of the dryer 10 and / or a comminution device 14.

[0065] The battery recycling system 90 has at least one inerting unit 38. The inerting unit 38 is intended for inerting the shredding device 14. The inerting unit 38 is intended for inerting the intermediate storage device 32. The inerting unit 38 is intended for inerting the dryer device 10. The inerting unit 38 has an inert gas supply to the shredding device 14, the intermediate storage device 32, and / or the dryer device 10. The inerting unit 38 uses nitrogen as the inert gas. The inert gas is metered via valves, the valves being controlled by the control and / or regulating unit 60, which controls a supply 28 to the shredding device 14, the intermediate storage device 32, and / or the dryer device 10.

[0066] Figure 3 schematically shows the dryer 10. The dryer 10 includes the vacuum unit 20. The dryer 10 includes a heating unit 50. The dryer 10 includes a control unit 60. The control unit 60 is provided for carrying out the method for drying the at least one battery material with at least part of the dryer 10. The control unit 60 is provided for carrying out the method for drying the at least one battery material with the dryer 10. The control unit 60 is provided for controlling the vacuum unit 20 in a low-pressure range. The control unit 60 is provided for controlling the heating unit 50 in a low-temperature range. The control unit 60 controls the vacuum unit 20 in multiple stages during the drying 100 of the battery material.The control unit 60 controls the heating unit 50 in multiple stages during the drying process 100 of the battery material. The control unit 60 controls the vacuum unit 20 at least to remove low-boiling substances from the battery material. The control unit 60 controls the vacuum unit 20 at least to remove high-boiling substances from the battery material. The control unit 60 controls the heating unit 50 at least to remove low-boiling substances from the battery material. The control unit 60 controls the heating unit 50 at least to remove high-boiling substances from the battery material.

[0067] The drying device 10 has at least one drying container 30. The drying container 30 is designed to hold the at least one battery material. The drying container 30 has a capacity of at least substantially between 50 l and 32,000 l. The battery material is fed in via a feed 28 from the comminution device 14. The drying container 30 has an inlet 70, which is designed for feeding the battery material into the drying container 30. The drying container 30 has at least one fluid valve 72, which is designed to release fluids generated during the drying process of the battery material from the drying container 30. The drying container 30 has at least one outlet 74, which is designed for discharging the dried battery material.

[0068] The drying device 10 includes an agitator 42. The agitator 42 has a stirring element 44, which is designed to mix the battery material in the drying container 30. The agitator 42 has an agitator shaft 46 to which the stirring element 44 is attached. The agitator 42 has a drive unit 40, which is designed to drive at least the stirring element 44. The drying container 30 has at least one sealing unit 80. The sealing unit 80 is designed to be at least substantially openable for cleaning and / or maintenance of the drying container 30. The drying container 30 is hermetically sealed for drying the battery material. The sealing unit 80 has a gasket 82. The gasket 82 seals the drying container 30 during the drying of the battery material. A temperature can be set in the drying container 30 by means of the heating unit 50.The heating unit 50 is designed to set a temperature in the drying container 30. The vacuum unit 20 is used to set a pressure in the drying container 30.

[0069] The dryer 10 has at least one sensor unit 62. The sensor unit 62 is designed to detect at least one drying parameter. The control unit 60 performs the multi-stage control of the heating unit 50 based on the drying parameters detected by the sensor unit 62. The control unit 60 performs the multi-stage control of the vacuum unit 20 based on the drying parameters detected by the sensor unit 62. The sensor unit 62 is designed to detect at least one temperature in the drying container 30. The sensor unit 62 has at least one temperature sensor element. The sensor unit 62 is designed to detect the completion of the removal of the low-boiling substances. The sensor unit 62 is designed to detect a temperature increase after the removal of the low-boiling substances.The vacuum unit 20 reduces the pressure in the drying container 30 by means of a control unit 60 based on the temperature increase detected by the sensor unit 62.

[0070] Figure 4 shows the dryer device 10 with at least one vapor filter unit 92. The vapor filter unit 92 has a vapor line. The vapor line is designed to discharge the exhaust gas stream generated during drying from the drying hopper 30. The vapor filter unit 92 is designed to separate entrained solid particles from the vapor stream. The vapor filter unit 92 has a vapor filter element 94. The vapor filter element 94 is designed to separate solid particles from the vapor stream. The vapor filter unit 92 is optionally designed as a multi-stage unit. The vapor filter unit 92 has a further vapor filter element 96. The further vapor filter element 96 is designed to separate solid particles from the vapor stream. The vapor filter unit 92 has a bypass 98.The bypass 98 is designed to divert the exhaust gas flow in the event of excessive differential pressure via the vapor filter element 94 and / or the further vapor filter element 96. The vapor filter unit 92 is designed to be heated by a heating unit 48. The control unit 60 is designed to control the heating unit 48 of the vapor filter unit 92.

[0071] The solvent recovery unit 16 includes a condenser unit 84. The condenser unit 84 includes a pre-capacitor 86. The condenser unit 84 includes a post-capacitor 88. The condenser unit 84 includes a defrosting unit 68. The defrosting unit 68 is designed to prevent the higher-boiling electrolytes in the exhaust gas stream from freezing. The defrosting unit 68 is designed to defrost at least the high-boiling electrolytes. The solvent recovery unit 16 is connected to a heating unit 49 for temperature control. The control unit 60 is designed to control the heating unit 49 of the solvent recovery unit 16.

[0072] The vacuum unit 20 is located in the solvent recovery unit 16. The vacuum unit 20 is situated between the pre-condenser 86 and the post-condenser 88. The vacuum unit 20 is configured as a screw-type positive displacement vacuum pump. Alternatively, the vacuum unit 20 is configured as a rotary vane pump. To maintain the vacuum performance of the vacuum unit 20, regular flushing of the screw-type positive displacement vacuum pump and / or rotary vane pump with a flushing medium is provided.

[0073] The heating unit 50 of the dryer 10 has a fluid circuit. The heating unit 50 has at least one heating element 66 for heating the fluid circuit. The fluid circuit is preferably designed as an oil circuit. The heating unit 50 has at least one jacket heating element 64. The fluid circuit passes through the jacket heating element 64. The jacket heating element 64 is designed to heat the battery material on the wall side for the removal of the low-boiling elements and / or the high-boiling elements. The dryer 10 has an alkaline scrubber 76. The dryer 10 has the alkaline scrubber 76 after the solvent recovery unit 16. The scrubber 76 is supplied with an alkaline washing solution, such as a sodium and / or potassium hydroxide solution, which neutralizes the acidic exhaust gas components.The Wäscher 76 is equipped with a pH control system which provides continuous monitoring and re-dosing of the alkali component via inline pH probes.

[0074] The dryer device 10 includes a thermal oxidizer 36. The thermal oxidizer 36 is designed for afterburning the exhaust gas stream. Alternatively or additionally, the dryer device 10 includes a sorptive exhaust gas purification system 78. The sorptive exhaust gas purification system 78 is designed as an activated carbon monolith or in the form of a zeolite-coated rotor.

[0075] The dryer 10 is designed to be at least substantially resistant to halogenated hydrogen gases. The dryer hopper 30 of the dryer 10 is designed to be at least substantially resistant to halogenated hydrogen gases. The solvent recovery unit 16 of the dryer 10 is designed to be at least substantially resistant to halogenated hydrogen gases. Components of the dryer 10 are made of Hastelloy. Heat exchangers within the solvent recovery unit 16 are designed as graphite heat exchangers or are provided with PTFE and / or PFA linings. Seals of the dryer 10 and / or the solvent recovery unit 16 are made of FFKM elastomers.

[0076] Figure 5 shows a flowchart of the process for drying the at least one battery material. The process is for drying the at least one battery material using the drying device 10. The process is for drying the at least one battery material using the industrial drying device 10.

[0077] In at least one process step, battery material is crushed 102. The crushing 102 of the battery material takes place in the crushing device 14. The crushed battery material is fed to the drying device 10.

[0078] In a further process step, the battery material is dried in a low-temperature environment. In this process step, the battery material is dried in a low-pressure environment. The drying of the battery material in the low-temperature and / or low-pressure environment comprises at least two drying steps.

[0079] In at least one drying step 120, the low-boiling elements are removed from the battery material. In at least one further drying step 122, the high-boiling elements are removed from the battery material.

[0080] Drying step 120 for removing the low-boiling components and drying step 122 for removing the high-boiling components are carried out in the individual drying vessel 30 of the dryer 10. These drying steps are performed in batch mode. The dryer 30 has a receiving chamber in which drying step 120 and drying step 122 are performed. Drying 100 is carried out with stirring and / or mixing, and the dryer 10 includes at least the agitator 42 for mixing the battery material, at least in the dryer 30.

[0081] The drying step 122 for removing the high-boiling elements takes place at a higher temperature 162 than the drying step 120 for removing the low-boiling elements. Figure 7 shows a temperature profile 150 during the drying 100 of the battery material in the low-temperature and low-pressure range, plotted against a temperature axis 206 and a time axis 204. The temperature 160 of the drying step 120 for removing the low-boiling elements is increased to that of the drying step 122 for removing the high-boiling elements. After completion 200 of the drying step 120 for removing the low-boiling elements, a transition to the drying step 122 for removing the high-boiling elements occurs. The temperature profile 158 during the transition between the drying step 120 for removing the low-boiling elements and the drying step 122 for removing the low-boiling elements is caused by controlled self-heating of the battery material.After the completion of drying step 120 for the removal of the low-boiling components, thermal energy is further supplied, adjusted to remove the low-boiling components. Due to the higher boiling point of the high-boiling components at a set pressure of 180, the battery material continues to heat up until the high-boiling components evaporate at the higher temperatures. The thermal energy is supplied by the heating unit 50. Once the high-boiling components have been at least substantially removed from the battery material, drying step 122 for the removal of the high-boiling components is completed.

[0082] In drying step 120 for the removal of the low-boiling elements, drying takes place at least to a significant extent at a temperature of 160, not exceeding 80 °C. The battery material is dried in drying step 120 for the removal of the low-boiling elements, at least approximately and to a significant extent, at a constant temperature profile 152, with a temperature of 160, not exceeding 80 °C. During a temperature start-up 156, the temperature of the drying device 10 for drying step 120 for the removal of the low-boiling elements is set. The battery material is fed into the drying container 30 after the temperature start-up 156. Alternatively, the battery material is fed into the drying container 30 either before or during the temperature start-up 156.

[0083] In drying step 122 for the removal of high-boiling components, drying takes place at least to a substantial extent at a temperature of at least 80 °C. The removal of high-boiling components takes place at a temperature of at least 80 °C to a substantial extent between 80 °C and 110 °C. In drying step 122 for the removal of high-boiling components, the battery material is dried at least approximately and to a substantial extent at a constant temperature profile 154 with a temperature of at least 80 °C.

[0084] The pressure 180 in drying step 122 for removing the high-boiling elements is set lower than in drying step 120 for removing the low-boiling elements. Figure 7 shows a pressure profile 170 during the drying 100 of the battery material in the low-temperature and low-pressure range, plotted against a pressure axis 208 and a time axis 204. The pressure 182 is reduced from drying step 120 for removing the low-boiling elements to drying step 122 for removing the high-boiling elements. The pressure 180, 182 is set by the vacuum unit 20. A pressure profile 178 in a transition between drying step 120 for removing the low-boiling elements and drying step 122 for removing the high-boiling elements is achieved by lowering the pressure set in the drying vessel 30.

[0085] In drying step 120 for the removal of the low-boiling elements, drying takes place at least to a substantial extent at a pressure of at least 300 hPa. The battery material is dried in drying step 120 for the removal of the low-boiling elements at least approximately and to a substantial extent at a constant pressure profile 172 at a pressure of at least 300 hPa. During a pressure start 176, the pressure of the dryer device 10 for drying step 120 for the removal of the low-boiling elements is set. The pressure start 176 is simultaneous with the temperature start 156.

[0086] In drying step 122 for the removal of the high-boiling substances, drying takes place at least to a significant extent at pressure 180 of at most 300 hPa. In drying step 120 for the removal of the low-boiling substances, the battery material is dried at least approximately and at least to a significant extent at a constant pressure profile 174 with pressure 180 of at most 300 hPa.

[0087] In a further process step, solvent recovery 104 of the fluid produced during drying takes place. Solvent recovery 104 occurs during the drying 100 of the battery material. A fluid produced in the drying step 120 to remove the low-boiling substances is further processed in solvent recovery 104. A fluid produced in the drying step 122 to remove the high-boiling substances is further processed in solvent recovery 104. The evaporated solvents are condensed in solvent recovery 104 and collected in at least one recovery tank 22.

[0088] In a further process step, the fluid produced during drying 100 is purified. The fluid produced in drying step 120 to remove the low-boiling substances is purified by the purification unit 18. The low-boiling substances evaporated during drying step 120 are extracted from the dryer 10 and directed to the purification unit 18. The fluid produced in drying step 120 to remove the low-boiling substances is purified of hydrogen fluoride in the purification unit 18. The fluid produced in drying step 122 to remove the high-boiling substances is purified by the purification unit 18. The high-boiling substances evaporated during drying step 122 are extracted from the dryer 10 and directed to the purification unit 18. The fluid produced in drying step 122 to remove the high-boiling substances is purified of hydrogen fluoride in the purification unit 18.In a further process step, the purified fluid leaves the cleaning unit 18 at output 108 and is safely released into an environment.

[0089] The cleaning unit 18 functions as a gas scrubber, absorbing hydrogen fluoride in a scrubbing liquid. The contaminated fluid from the drying tank 30 enters the gas scrubber, where it passes through the scrubbing liquid and absorbs the pollutants, such as hydrogen fluoride. The scrubbing liquid is distributed within the gas scrubber via spray nozzles or packing material. The cleaned fluid exits the gas scrubber and is safely released into the environment. The scrubbing liquid is circulated by a pump and regenerated or replaced as needed. The loaded scrubbing liquid, containing the absorbed hydrogen fluoride, is collected and treated. This treatment step involves removing the absorbed pollutants to prepare the scrubbing liquid for reuse.

[0090] In a further process step, the dried battery material is stored. The dried battery material is stored in at least one storage container. After storage, the dried battery material undergoes further processing. Alternatively, the dried battery material is processed directly after drying. The dried battery material is conveyed on a conveyor belt to a further processing plant.

[0091] After at least one drying cycle 220, the drying container 30 is cleaned and / or serviced by opening the closure unit 80. The drying cycle 220 includes at least the drying 100 of the battery material in the low-temperature and low-pressure range. The cleaning and / or service of the drying container 30 is performed after a number of drying cycles 220. The closure unit 80 is sealed with the gasket 82 during the drying 100 of the battery material in the low-temperature and low-pressure range. In the drying step 120 for removing the low-boiling elements, the pressure 102 is set, which is sealed with the gasket 82. In the drying step 122 for removing the high-boiling elements, the pressure 180 is set, which is sealed with the gasket 82.

[0092] Figure 6 shows a flowchart of an alternative method for drying at least one battery material using the dryer device 10. The process steps in Figure 6, which are assigned the same reference numerals as in Figure 5, are essentially the same.

[0093] During tempering 116, the crushed battery material is fed to the intermediate storage device 32. The battery material is fed to the intermediate storage device 32 before drying. In the intermediate storage device 32, the battery material is mixed. The intermediate storage device 32 is inerted by supplying nitrogen via at least one nitrogen line. The battery material is tempered in the intermediate storage device 32. Tempering 116 is achieved by heating the wall of the intermediate storage device 32. Tempering 116 takes place within a temperature range of 60 °C to 70 °C. This tempering causes some of the low-boiling elements to evaporate before the drying step in the dryer 10. Tempering 116 at a defined temperature limits local temperature peaks in the battery material. A partial negative pressure is established in the intermediate storage device 32.The negative pressure is set within a pressure range of -5 mbar to -30 mbar relative to ambient pressure. The nitrogen supplied to the intermediate storage device 32 is continuously extracted via a fan unit 58 with at least one fan or blower. The exhaust gas is routed directly to the thermal oxidizer 36, which is also intended for the exhaust gas treatment of the dryer 10 and / or a comminution device 14.

[0094] After the battery material has been tempered 116 in the intermediate storage unit 32, it is fed to the dryer unit 10. During a pressure reduction 118 phase into the low-pressure range, the exhaust gases are bypassed 98 around the scrubber 76. The exhaust gases are routed via an adjustable bypass line with a controllable bypass valve. The exhaust gases are then fed directly to the thermal oxidizer 36.

[0095] Alternatively, in pressure reduction 118, the pressure is lowered into the low-pressure range via a prolonged pressure reduction phase. The ramp time to reach the low-pressure range for removing the low-boiling substances is extended by at least 50% compared to a direct pressure reduction. The pressure reduction takes place over at least 5 minutes. In supply 122, the exhaust gas flow is fed to the vapor filter unit 92 during the drying of the battery material in the dryer 10. To reduce pressure loss in the dryer 10, the vapor filter unit 92 is heated. A temperature of at least 40 °C is set at the vapor filter unit 92. Temperature control of the vapor filter unit 92 is carried out via the control unit 60 of the dryer 10.

[0096] To reduce pressure loss in the dryer 10, an exhaust gas stream is filtered in multiple stages by the vapor filter unit 92. During coarse filtration 124, the exhaust gas stream passes over the first, coarse-pored vapor filter element 94. This coarse-pored vapor filter element 94 separates solid agglomerates and fiber fragments. During fine filtration 126, the exhaust gas stream passes over the second, fine-pored vapor filter element 96. This fine-pored vapor filter element 96 retains any remaining fine dust particles and condensing aerosols.

[0097] In a bypass 128, an exhaust gas flow is routed through a bypass 98 past at least one vapor filter element 94, 96 of the vapor filter unit 92 to reduce pressure loss in the dryer device 10. Alternatively, in a bypass 128, an exhaust gas flow is routed through a bypass 98 past both vapor filter elements 94, 96 of the vapor filter unit 92 to reduce pressure loss in the dryer device 10. The bypass 98 opens when the differential pressure exceeds 50 mbar. The switching of the valve to the exhaust gas flow via the bypass 98 is based on continuous differential pressure monitoring by the control unit 60. In an alternative embodiment, the exhaust gas flow is routed via the bypass 98 only past the coarse-pored vapor filter element 94 in the bypass 128 (shown with dashed lines).

[0098] In solvent recovery 104, at least the lighter-boiling substances are at least partially recovered from the exhaust gas stream. In solvent recovery 104, at least the higher-boiling substances are at least partially recovered from the exhaust gas stream. The exhaust gas stream from the drying tank 30 is transferred to solvent recovery 16 after passing through the vapor filter unit 92, where the lighter-boiling substances and / or higher-boiling substances are liquefied and / or frozen by condensation. The lighter-boiling substances and / or higher-boiling substances are separated by solvent recovery 16. Solvent recovery 16 is at least partially heated. The piping units of solvent recovery 16 are heated. The pre-condenser 86 of solvent recovery unit 16 is heated. A temperature of at least 40 °C is maintained in solvent recovery unit 16.

[0099] The exhaust gas stream from solvent recovery 16 is fed to the condenser unit 84. In the condenser unit 84, evaporated components, at least the low-boiling and / or high-boiling substances, are liquefied and / or frozen. In particular, the condenser unit 84 has several condenser stages.

[0100] During condensation 130, the exhaust gas stream is fed to the pre-condenser 86 of the condenser unit 84. In the pre-condenser 86, the vaporized components of the exhaust gas stream are at least partially liquefied by cooling in the temperature range between 35 °C and 50 °C.

[0101] In a further condensation step 132, the exhaust gas stream is fed to the post-condenser 88 of the solvent recovery unit 16 after passing through the pre-condenser 86. Any remaining condensable vapors are separated in the post-condenser 88.

[0102] The defrosting unit 68 of the pre-capacitor 86 of the condenser unit 84 prevents icing of high-boiling elements. The defrosting unit 68 of the pre-capacitor 86 of the condenser unit 84 also defrosts any ice that has formed. The defrosting unit 68 is controlled by the control and / or regulating unit 60.

[0103] In alkaline scrubbing 134, the exhaust gas stream is fed to the scrubber 76 after solvent recovery 16. A pH value between 8 and 10 is set.

[0104] The exhaust gas stream undergoes thermal oxidation 36 after solvent recovery 16 and scrubber 76. This thermal oxidation is carried out using a regenerative afterburner system and takes place at temperatures between 750 °C and 850 °C.

[0105] Alternatively or additionally, the exhaust gas flow is treated in a sorptive exhaust gas purification stage.

[0106] 138 after solvent recovery 16, the exhaust gas is subjected to sorptive cleaning 78 after scrubber 76. The sorptive cleaning 78 is carried out at a maximum temperature of 120 °C.

[0107] In further processing 112, the exhaust gas is discharged into a further process or into the open air after sorptive exhaust gas purification 78 and / or thermal oxidation 36.

[0108] Reference sign

[0109] 10 Dryer device

[0110] 12 Industrial drying device

[0111] 14. Shredding device

[0112] 16 Solvent recovery

[0113] 18 cleaning units

[0114] 20 vacuum units

[0115] 22 Recovery tank

[0116] 24th issue

[0117] 26 storage containers

[0118] 28 Supply

[0119] 30 drying containers

[0120] 32 Intermediate bunker device

[0121] 34 Mixing plant

[0122] 36 Thermal Oxidation

[0123] 38 inerting units

[0124] 40 drive unit

[0125] 42 Agitator

[0126] 44 Stirring element

[0127] 46 Stirrer shaft

[0128] 48 heating units

[0129] 49 heating units

[0130] 50 heating units

[0131] 52 heating units

[0132] 54 Jacket heating element

[0133] 56 Heating element

[0134] 58 fan unit

[0135] 60 Control and / or regulating unit

[0136] 62 sensor units

[0137] 64 Sheath heating element Heating element

[0138] defrost unit

[0139] inlet

[0140] Fluid valve

[0141] Outlet

[0142] washer

[0143] Sorptive exhaust gas purification

[0144] Locking unit

[0145] Mechanical seal

[0146] Capacitor unit

[0147] pre-capacitor

[0148] Post-capacitor

[0149] Battery recycling system

[0150] Vapor filter unit

[0151] Vapor filter element

[0152] Vapor filter element

[0153] bypass

[0154] T dry

[0155] Shredding

[0156] Solvent recovery

[0157] Clean

[0158] output

[0159] storage

[0160] Further processing

[0161] storage

[0162] Tempering

[0163] Pressure reduction

[0164] Drying step

[0165] Drying step

[0166] supply

[0167] Coarse filtration Fine filtration

[0168] Bypass

[0169] Condense

[0170] Condense

[0171] Alkaline laundry

[0172] Thermal oxidation

[0173] Sorptive exhaust gas purification stage

[0174] Temperature profile

[0175] Temperature profile

[0176] Temperature profile

[0177] Temperature start-up

[0178] Temperature profile

[0179] temperature

[0180] temperature

[0181] Pressure curve

[0182] Pressure curve

[0183] Pressure curve

[0184] Pressure start

[0185] Pressure curve

[0186] Pressure

[0187] Pressure

[0188] Diploma

[0189] Diploma

[0190] Timeline

[0191] Temperature axis

[0192] Pressure axis

[0193] Drying cycle

Claims

Claims 1. Method for drying at least one battery material with a drying device (10), in particular an industrial drying device (12), comprising at least the following steps: Drying (100) the battery material in a low temperature and / or low pressure range, wherein in at least one drying step (120) low-boiling substances are removed from the battery material, and wherein in at least one further drying step (122) high-boiling substances are removed from the battery material.

2. Method according to claim 1, characterized in that the drying step (120) for removing the low-boiling substances and the drying step (122) for removing the high-boiling substances are carried out in a single drying container (30) of the dryer device (10) and / or in a batch operation.

3. Method according to claim 1 or 2, characterized in that the drying step (122) for removing the high boiling points is carried out at a higher temperature (162) than the drying step (120) for removing the low boiling points.

4. Method according to one of the preceding claims, characterized in that in the drying step (122) for removing the high boiling points, the drying takes place at least to a substantial extent at a temperature (162) of at least 80 °C.

5. Method according to one of the preceding claims, characterized in that in the drying step (120) for removing the low boiling points, the drying takes place at least to a substantial extent at a temperature (160) of at most 80 °C.

6. Method according to one of the preceding claims, characterized in that the pressure (180) in the drying step (122) for removing the high-boiling substances is set lower than in the drying step (120) for removing the low-boiling substances.

7. Method according to one of the preceding claims, characterized in that a fluid formed in the drying step (120) for removing the low-boiling substances and / or in the drying step (122) for removing the high-boiling substances is purified by a purification unit (18), in particular of at least hydrogen fluoride.

8. Method according to one of the preceding claims, characterized in that after at least one drying cycle (220), at least one drying container (30) is cleaned and / or serviced by opening a closure unit (80).

9. Method according to one of the preceding claims, characterized in that in a pressure reduction phase into the low-pressure range the exhaust gases are routed past a scrubber (76) via a bypass and / or a reduction of the pressure into the low-pressure range takes place over a time-extended pressure reduction phase.

10. Method according to one of the preceding claims, characterized in that an exhaust gas stream of the dryer device (10) is filtered in multiple stages with a vapor filter unit (92) and / or is passed by a bypass (98) past at least one vapor filter element (94; 96) of the vapor filter unit (92).

11. Method of at least one of the preceding claims, characterized in that a defrosting unit (68) of a capacitor unit (84), in particular a pre-capacitor (86) of the capacitor unit (84), prevents icing of high-boiling elements and / or defrosts icing.

12. Method according to one of the preceding claims, characterized in that the battery material is supplied to an intermediate storage device (32) before drying (100).

13. Method according to claim 12, characterized in that the battery material is temperature controlled in the intermediate storage device (84).

14. Method at least according to claim 12, characterized in that a negative pressure is set at least partially in the intermediate bunker device (84).

15. Drying device (10), in particular industrial drying device (12), for drying at least one battery material, in particular at least partially for carrying out the method according to one of the preceding claims, comprising a vacuum unit (20) and / or a heating unit (50), and a control and / or regulating unit (60) which is provided to regulate the vacuum unit (20) and / or the heating unit (50) in a low temperature range and / or low pressure range, characterized in that the control and / or regulating unit (60) controls the vacuum unit (20) and / or the heating unit (50) in multiple stages during the drying of the battery material.

16. Drying device (10) according to claim 15, characterized by at least one drying container (30) in which a pressure can be set by means of the vacuum unit (20) which has at least one closure unit (80) which is designed to be at least substantially openable for cleaning and / or maintenance of the drying container (30).

17. Drying device (10) according to one of claims 15 to 16, characterized by at least one sensor unit (62) which is at least provided to detect at least one drying parameter, in particular a temperature, humidity and / or a gas composition, in the drying container (30), wherein the control and / or regulating unit (30) performs the multi-stage control based on the drying parameters.

18. Dryer device (10) at least according to claim 15, characterized in that the vacuum unit (20) is designed as a screw displacement vacuum pump and / or rotary vane pump.

19. Drying device (10) at least according to claim 15, characterized in that at least the drying device (10), in particular a drying container (30) and / or a solvent recovery (16) of the drying device (10), is designed to be at least substantially resistant to halogenated hydrogen gases.

20. Battery recycling system (90) at least for carrying out the method according to one of claims 1 to 14 with a drying device (10) according to one of claims 15 to 19.

21. Battery recycling system (90) according to claim 20, characterized by a shredding device (14) which is provided to supply shredded battery material, wherein the drying device (10) is provided to dry the shredded material.

22. Battery recycling system (90) at least according to claim 20, characterized by an intermediate storage device (32), wherein the intermediate storage device (32) has a fluid circuit for temperature control of the battery material, in particular decoupled from the dryer device (10).

23. Battery recycling system (90) at least according to claim 20, characterized in that a nominal volume of the intermediate storage device (32) is at least a multiple of a nominal volume of the dryer device (10).

24. Control and / or regulating unit (60), in particular at least partially of the dryer device (10) according to one of claims 15 to 19, for carrying out the method according to one of claims 1 to 14.

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