System and process for producing asphalt

Abstract

A system (1) for producing asphalt comprises at least one energy supply device (7, 8, 9) for supplying energy, an energy store (5, 12), connected to the at least one energy supply device (7, 8, 9), for storing the supplied energy, and an asphalt mixing system (2) having at least one drying system (3) which is connected to the energy store (5, 12).

Description

[0001] Plant and process for asphalt production

[0002] The content of the German patent application DE 10 2024 202 765.0 is incorporated herein by reference.

[0003] The invention relates to a plant and a method for producing asphalt.

[0004] During asphalt production, various components are prepared, particularly dried, and mixed together. Asphalt production is notably not constant and occurs in batch operation. Depending on the order, asphalt production may need to be carried out at short notice. Sufficient energy must be provided for asphalt production. The requirements of short-term availability and high energy quantities are met by fossil fuels burned in industrial combustion plants. To reduce emissions, especially those containing CCE, strict regulations apply to the combustion process. In particular, complex preparatory measures are required, especially for solid fuels, such as a fine grading curve. The investment costs for industrial combustion plants are high. The combustion of fossil fuels is problematic from an ecological perspective.

[0005] The invention is based on the object of improving the energy supply for asphalt production, in particular enabling a flexible, particularly time-independent, energy supply for asphalt production. This object is achieved by a system having the features of claim 1 and by a method having the features of claim 9.

[0006] The core of the invention is that energy is provided by an energy supply device and stored in an energy storage device. The energy storage device is connected, in particular directly, to the at least one energy supply device. Multiple, in particular different, energy storage devices can also be present.

[0007] The energy storage unit is connected to at least one drying system of an asphalt mixing plant, in particular directly and in particular by heat transfer. In the drying system, which is designed in particular as a drying drum, a component required for asphalt production is dried. The component is in particular white mineral and / or old asphalt granulate, also known as recycled asphalt.

[0008] Surprisingly, it was discovered that the use of the energy storage system makes it possible to temporally and / or spatially decouple energy supply on the one hand from energy use in the asphalt mixing plant on the other. This allows energy to be made available in advance and stored in the energy storage system. Whenever there is an energy demand in the asphalt mixing plant, this can be met by the energy storage system.

[0009] It is also possible for at least one further energy supply device to be directly connected to the asphalt mixing plant, in particular to the at least one drying plant, in an energy-transmitting manner. This further energy supply device is, in particular, designed separately from the energy storage device, i.e., is not connected to the energy storage device. The at least one further energy supply device can be used to cover energy peaks during operation of the asphalt mixing plant. It is advantageous if the at least one further energy supply device enables short-term operation, which is, in particular, independent of external influences, such as sunshine and / or wind.

[0010] According to the invention, it was recognized that the use of the energy storage system makes it possible to tap into energy sources for asphalt production that were previously unsuitable for asphalt production, particularly due to the volatility of energy supply. In particular, renewable primary energy sources can be used for electricity generation and / or heat utilization. In principle, electrical power, which can also be generated non-renewably, can be stored as supplied energy, particularly in the form of heat. This makes asphalt production independent of fossil energy sources and / or fossil fuels. This results in a more flexible energy supply for asphalt production.

[0011] In particular, it was also recognized that sector coupling is possible by using energy from other industrial sectors as waste heat for asphalt production.

[0012] A system according to claim 2 enables efficient energy storage, particularly in the energy form required for the at least one drying system. Energy losses due to energy conversion are avoided. The overall efficiency of the system's operation is increased.

[0013] The thermal storage device comprises, in particular, a heat storage material with which heat can be stored easily and, in particular, over a longer period of time, in particular with a reduced loss rate and, in particular, essentially without loss. The heat storage material is, in particular, hot water, molten salt and / or rock, which in particular has a porous surface, and / or phase change material. The rock comprises, in particular, ceramic materials. Energy, in the form of heat, can advantageously be absorbed via hot gas, in particular hot exhaust gas and / or hot air, due to the surface area of ​​the rock being enlarged by the pores. In particular, the hot gas flows through the porous rock, which is thereby heated and serves as a storage medium. The porous rock is, in particular, in the form of a bulk material, in particular as a bulk material storage device.

[0014] The discharging of the energy storage device, i.e. the release of heat from the energy storage device to the drying system, takes place in particular by means of a fan to generate a cold gas stream that is guided through the thermal storage device. The cold gas absorbs the heat stored in the thermal storage device, in particular in the porous rock, and can be supplied to the at least one drying system as hot gas, in particular as hot air, in particular with a temperature of at least 400°C, in particular of at least 500°C, and in particular of at least 550°C. A system according to claim 3 enables advantageous loading of the energy storage device. The fact that the at least one energy supply device provides heat at a sufficient temperature level ensures the heat supply to the drying system.In particular, it is possible that the energy to be stored in the energy storage device is formed from a combination of waste heat from an energy supply device and generated heat.

[0015] A system according to claim 4 enables uncomplicated combustion. In particular, the combustion device is designed as a grate firing device in which the fuel lies on a grate and burns. The grate can be designed as a flat grate, a traveling grate, a stepped grate, a bulk grate, or a roller grate. The combustion device particularly enables the use of biogenic solid fuels. In particular, it is not necessary to provide the solid fuels in dust form. The preparation effort for providing the solid fuel is reduced. In particular, the preparation effort for grinding and / or sieving the solid fuel is eliminated. For example, wood chips, pellets, and / or split logs can be burned. The overall efficiency of the system's operation is increased.

[0016] In principle, any combustion device capable of providing combustion energy in the form of heat can be considered as a combustion device according to claim 4. In particular, a combustion device is a stationary hot gas generator system.

[0017] A system according to claim 5 is particularly ecologically advantageous. Although renewable energy is volatile, it can be advantageously used for asphalt production through decoupling via the energy storage system. In particular, electrical power and / or heat, each generated using renewable energy, can be advantageously stored directly or indirectly in the energy storage system.

[0018] A system according to claim 6 simplifies energy conversion, in particular from electrical current to heat. An energy conversion device is directly connected to the at least one energy supply device and in particular to the energy storage device. The energy supply device is designed in particular as an electric heating device to generate hot gas, in particular hot air, using the electrical current, which serves to charge the thermal storage device.

[0019] A system according to claim 7 enables the storage of electrical energy, in particular in the form of a thermal battery storage device. This makes it possible, in particular, to spatially decouple the energy supply device and the energy storage device from one another. It is particularly conceivable for the energy storage device to be connected to an electrical supply network, in particular to a public power grid. The electrical storage device is connected, in particular, to an energy conversion device, in particular an electric heating device.

[0020] A system according to claim 8 enables flexibility with regard to the temperature level at which heat is delivered to the drying system. By means of a temperature conversion device, the temperature level provided by the at least one energy supply device, in particular in the form of waste heat or as heat from a combustion plant, can be converted to a temperature level required for the thermal storage device. In particular, the temperature conversion device is designed to raise or lower the temperature in the energy storage device. The temperature conversion device is designed in particular as a high-temperature heat pump. A high-temperature heat pump is suitable for generating heat for a temperature range up to 150°C. A high-temperature heat pump is suitable for various applications, in particular when a heat source provides waste heat at a required temperature level.

[0021] A method according to claim 9 essentially has the advantages of the system according to the invention, to which reference is hereby made.

[0022] Both the features specified in the patent claims and the features specified in the following exemplary embodiment of a system according to the invention are suitable, either individually or in combination with one another, for further developing the subject matter of the invention. The respective combinations of features do not represent any limitation with regard to further developments of the subject matter of the invention, but are essentially merely exemplary in nature.

[0023] Further advantageous embodiments, additional features, and details of the invention will become apparent from the following description of an embodiment with reference to the drawings. They show:

[0024] Fig. 1 is a schematic representation of an asphalt production plant according to the invention. A plant designated as a whole by 1 in Fig. 1 is used for asphalt production.

[0025] Plant 1 comprises an asphalt mixing plant 2, in which components such as white mineral and / or recycled asphalt required for asphalt production are dried in at least one drying plant 3 and mixed in an associated mixing unit 4. The at least one drying plant 3 is designed, in particular, as a drying drum. It is understood that multiple drying plants 3 may be present. Storage containers and / or dosing devices may also be connected to the mixing unit 4 to add further components to the mixing unit 4.

[0026] It is understood that the asphalt mixing plant 2 may include additional components required for its operation, such as a filter dust removal system. For illustrative purposes, these additional components are not shown in Fig. 1.

[0027] An energy storage device 5, designed as a thermal storage device, is connected to the at least one drying system 3. The energy storage device 5 comprises, in particular, a thermal storage material that allows energy to be absorbed, stored, and released again as needed. The thermal storage material is, in particular, a porous rock. The thermal storage device 5 serves to transfer heat to the drying system 3 of the asphalt mixing plant 2.

[0028] A fluid flow unit 6 is connected to the energy storage device 5, which can generate a fluid flow and supply it to the energy storage device 5. The fluid flow unit 6 is, in particular, a fan. At least one energy supply device 7, 8, 9 is also connected to the energy storage device 5.

[0029] A first energy supply device 7 enables the use of renewable energies. In particular, the first energy supply device 7 is a device for converting renewable energy into electricity, in particular a solar energy device, in particular a photovoltaic device, a wind energy device, in particular a wind turbine, and / or a hydropower device. The first energy supply device 7 is electrically connected to an energy conversion device 10. The energy conversion device 10 is in particular an electrical heating device, in particular an electrical air heater, for heating gas, in particular air, using the electrical energy provided by the first energy supply device 7. The energy conversion device 10 is connected to the energy storage device 5.This means that the first energy supply device 7, which serves to generate electricity from renewable primary energy sources, is connected indirectly, i.e. via the energy conversion device 10, to the energy storage device 5.

[0030] It is understood that the first energy supply device 7 can also comprise power generation systems that are only partially or not at all powered by renewable primary energy sources. It is essential that the generated electrical energy is converted into heat and / or temporarily stored.

[0031] Additionally or alternatively, the first energy supply device 7 can also be used to utilize heat from renewable primary energy sources and can be designed, in particular, as a geothermal device and / or solar thermal device. In this case, the first energy supply device 7 is directly connected to the energy storage device 5 via a direct line. The heat obtained from the renewable primary energy sources can be directly supplied to the energy storage device 5 via the direct line.

[0032] The second energy supply device 8 is a separate device, in particular from a different industrial sector. The second energy supply device 8 is operated, in particular, independently of the asphalt mixing plant 2. The second energy supply device 8 is connected to the energy storage device 5. The second energy supply device 8 is, in particular, a waste incineration plant. The second energy supply device simplifies and, in particular, enables sector coupling, i.e., in particular, the coupling of heat and electricity.

[0033] The third energy supply device 9 is a combustion device, which serves in particular for dispersing renewable and / or alternative fuels, which can be burned in particular unground form and in particular in the form of wood chips, pellets, and / or logs. The combustion device is designed in particular as a grate firing device. The third energy supply device 9 is connected to the energy storage device 5.

[0034] The system 1 has a temperature conversion device 11, which can be connected to the energy conversion device 10 and / or to the second and third energy supply devices 8, 9. The temperature conversion device 11 is connected upstream of the energy storage device 5 and enables a conversion of the temperature level of the heat provided by the energy supply devices 7, 8, 9, in particular to the temperature level required for the energy storage device 5. The temperature conversion device 11 is optional. The temperature conversion device 11 is, in particular, a heat pump and, in particular, a high-temperature heat pump.

[0035] The system 1 has a further energy storage device 12, which is designed as an electrical storage device, in particular in the form of a battery storage device. The electrical energy storage device 12 is in particular directly connected, in particular electrically, to the first energy supply device 7. Electrical current generated by the first energy supply device 7 using regenerative primary energy can be stored in the electrical energy storage device 12. The electrical energy storage device 12 is in particular electrically connected to the energy conversion device 10.

[0036] If the energy conversion device 10 is powered by the electrical energy storage device 12, the heat from the energy conversion device 10 can also be transferred directly to the drying system 3. In this case, the drying system 3 is not directly connected to the electrical energy storage device 12, but indirectly via the energy conversion device 10.

[0037] The electrical energy storage device 12 can also be connected to a power supply line, in particular to a public power grid, or connected to the first energy supply device 7 via the public power grid. A method for operating the system 1, in particular a method for producing asphalt, is explained in more detail below.

[0038] Energy is provided by the at least one energy supply device 7, 8, 9. Electrical energy is converted into heat in the energy conversion device 10 and supplied to the thermal energy storage device 5. Energy provided in the form of heat by the second and / or third energy supply device 8, 9 can be supplied directly to the thermal energy storage device 5. Alternatively, it is possible for the heat from the energy supply devices 7, 8, 9 and / or from the energy conversion device 10 to be converted, in particular lowered or raised, to a required temperature level by means of the temperature conversion device 11.

[0039] The thermal energy storage device 5 is charged by supplying heated gas, in particular heated air, to the energy storage device, with the heated gas flowing around the thermal energy storage material and thereby being heated. The heat can be stored by the thermal energy storage material. The gas cooled as a result of the heat transfer can be removed from the thermal energy storage device 5 via an exhaust air line (not shown in detail). If necessary, the cooled gas is cleaned, in particular in the thermal energy storage device 5 by means of the thermal storage material and / or in a filter system, in particular in the filter dedusting system of the asphalt mixing plant 2.

[0040] The charging process of the thermal energy storage device 5 is temporally and, in particular, spatially decoupled from the operation of the asphalt mixing plant 2 and, in particular, decoupled from an actual energy requirement in the asphalt mixing plant 2. The thermal energy storage device 5 can, in particular, also be charged when there is no energy requirement in the asphalt mixing plant 2, in particular if the thermal energy storage device 5 still has a thermal absorption capacity.

[0041] If there is an energy demand in the asphalt mixing plant 2, in particular because a component required for asphalt production, such as white mineral or recycled asphalt, is to be dried in the at least one drying plant 3, energy, in particular thermal energy, can be transferred from the thermal energy storage device 5 to the at least one drying plant 3. This is achieved in particular by the fluid flow unit 6, which generates a fluid flow in the form of a cold air flow and feeds it to the energy storage device 5. The cold air flow heats up as it flows through the energy storage device 5, exits the thermal energy storage device 5 as a heated air flow, and is then fed to the at least one drying plant 3 at a minimum temperature of 500°C.

[0042] It is advantageous if the energy supply, in particular the heat supply, from the thermal energy storage device 5 for the drying plant 3 is controlled and in particular regulated. This is advantageously done by means of a control / regulation unit 13, which is shown purely schematically in Fig. 1. The control / regulation unit 13 is in particular in signal connection with the fluid flow unit 6 andZor with the asphalt mixing plant 2, in particular with the at least one drying plant 3, in particular with sensors of the drying plant 3. The signal connection can be wired andZor wireless. In particular, a control signal can be generated with the control / regulation unit 13 and transmitted to the fluid flow unit 6 in order to trigger a fluid flow.The control signal is generated in particular as a function of a status signal which is transmitted in particular from the at least one drying system 3 itself and / or a corresponding sensor in and / or on the drying system 3 to the control / regulation unit 13.

[0043] The plant 1 enables an advantageous temporal decoupling of the energy supply by means of the energy supply devices 7, 8, 9 and the energy use in the at least one drying plant 3 of the asphalt mixing plant 2.

Claims

Patent claims 1. Plant for asphalt production comprising a. at least one energy supply device (7, 8, 9) for providing energy, b. an energy storage device (5, 12) connected to the at least one energy supply device (7, 8, 9) for storing the provided energy, c. an asphalt mixing plant (2) with at least one drying plant (3) connected to the energy storage device (5, 12).

2. System according to claim 1, characterized in that the energy storage device (5) is designed as a thermal storage device.

3. Plant according to one of the preceding claims, characterized in that the at least one energy supply device (7, 8, 9) provides heat at a temperature level of at least 400 °C in normal operation.

4. Plant according to one of the preceding claims, characterized in that the at least one energy supply device (9) is designed as a spreading device.

5. Plant according to one of the preceding claims, characterized in that the at least one energy supply device (7) is designed for the use of renewable energy, in particular for the conversion of renewable energy into electricity as a solar energy device, wind energy device and / or hydropower device, and / or for the use of heat from renewable energy, in particular as a geothermal device and / or solar thermal device.

6. Plant according to claim 5, characterized in that the at least one energy supply device (7) is connected to an energy conversion device (10), in particular an electric heating device, in particular an electric air heater.

7. System according to one of the preceding claims, characterized in that the energy storage device (12) is designed as an electrical storage device.

8. System according to one of the preceding claims, characterized by a temperature conversion device (11) which is connected to the at least one energy supply device (7, 8, 9) and the energy storage device (5), in particular arranged therebetween.

9. A method for producing asphalt, comprising the method steps a. providing energy by means of at least one energy supply device (7, 8, 9), b. storing the provided energy in an energy storage device (5, 12) connected to the at least one energy supply device (7, 8, 9), c. drying a component required for asphalt production in at least one drying system (3) of an asphalt mixing plant (2), d. mixing the dried component with further components to form asphalt.

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