BE1030687A1 - CO2-free production of artificial pozzolans, especially from clays - Google Patents

Abstract

The present invention relates to a system 10 for the thermal activation of fine-grained mineral raw materials for producing artificial pozzolans, the system 10 having a drying device 20, a preheater 30, a preheater 30 and a thermal treatment device 40, the fine-grained mineral raw material being transferred from the drying device 20 the preheater 30 is guided to the thermal treatment device 40, wherein a gas stream is supplied to the thermal treatment device 40 and is fed from the thermal treatment device 40 to the preheater 30, characterized in that a first gas flow heater 50 is arranged along the gas stream in front of the thermal treatment device 40.

Description

CO:-free production of artificial pozzolans, especially from clays

The invention relates to a system and a method for producing artificial

Pozzolans, especially from clays, avoiding fossil fuels to reduce CO2 emissions.

In contrast to clinker production, in which large amounts of CO are released from lime when burned, this is not the case when producing artificial pozzolans from natural clays for use as a cement substitute. Here the majority of CO2 emissions come from fossil fuels. However, since the processes rely on gaseous fuels, such as natural gas, or solid fuels, for example

Coal dust, but also designed for substitute fuels, the existing systems cannot simply be converted to energy from wind or solar. In order to be able to use these energy sources, a radical change is required

System construction necessary.

An energy storage system is known from WO 2022/115 721 A2.

A heating element and a process heater are known from DE 10 2014 102 474 A1.

From DE 10 2021 203 071, DE 10 2021 203 072, DE 10 2021 203 073 and the

DE 10 2021 203 074 discloses devices and methods for the thermal treatment of a mineral starting material. 23 Energy recovery when cooling color-optimized activated clays is known from DE 10 2020 211 750 A1.

The object of the invention is to provide a system and a method which also uses these new renewable energy sources for the production of artificial pozzolans in order to avoid CO2 emissions.

This task is solved by the system with those specified in claim 1

Features and by the method specified in claim 18

7 BE2022/5544

characteristics. Advantageous further developments result from the subclaims, the following description and the drawings.

The system according to the invention is used for the thermal activation of fine-grained particles

Mineral raw materials and for the production of artificial pozzolans. The system has a drying device, a preheater and a thermal

Treatment device. The thermal treatment device can be, for example, a calciner or activator. The fine-grained mineral raw material is transferred from the drying device via the preheater to the thermal

Treatment device guided. The thermal treatment device is a

Gas flow is supplied in countercurrent and supplied from the thermal treatment device to the preheater. In this case, the solid stream and gas stream can preferably also be conducted in cocurrent at some points and then separated again, for example, in a cyclone. Such systems are known to those skilled in the art from the prior art; reference is only given as an example

DE 10 2020 211 750 A1referenced.

According to the invention, along the gas flow in front of the thermal

Treatment device arranged a first gas flow heater. The system according to the invention therefore differs fundamentally from a system according to the state of the art

Technology. The energy is therefore no longer supplied via a burner in the thermal

Treatment device generated, but impressed by the first gas flow heater on the gas flow supplied to the thermal treatment device and over the

Gas stream is introduced into the thermal treatment device. This now makes it possible for the first time to use renewable energies, particularly from sun and wind, to produce artificial pozzolans.

The system according to the invention offers a further advantage. Since combustion no longer needs to take place, the gas stream does not have to contain any oxygen. This makes it possible to work with a pure inert gas atmosphere or with a reducing atmosphere for color optimization. This means that color optimization can be carried out in a single step during activation. Will be a different gas than

If air is used, it is preferably recirculated.

3 BE2022/5544

In a further embodiment of the invention, the fine-grained mineral

Raw material is a natural clay, pure or as a mixture, a clay-like substance

Zeolite, waste cement stone or a mixture thereof.

In a further embodiment of the invention, the system has at least one

Device for generating renewable energy, in particular one

Wind turbine or a solar field. The system particularly preferably has at least two different devices for generating renewable energy, for example a wind turbine and a solar field. In addition, the system can, for example, have a biogas plant and a gas turbine to operate in times without

Sun and wind from biogas CO: to generate neutral electricity. This enables greater flexibility even without large battery systems.

In a further embodiment of the invention, the system has at least one first energy storage device. The at least one first

Energy storage device is used in particular to equalize the energy generated from renewable sources, for example as a day-night balance for solar power. Here, a large first energy storage device can be provided, which is designed to supply all electrically operated system components. Alternatively, a plurality of smaller energy storage devices can be provided, each of which supplies individual or a few components of the system. As

Energy storage devices can be all known electrical ones

Energy storage devices are used, for example accumulators and

Capacitors, but also not purely electrical storage, such as a

Pumped storage plant or intermediate storage in a chemical product, for example hydrogen (combination of electrolysis/fuel cell).

In addition, the system can also have a connection to the general power grid. This not only allows fluctuations to be balanced out, but also in the event of an oversupply (and correspondingly low or negative price), electricity can also be used directly or put into an energy storage device.

4 BE2022/5544

Particularly preferably, the connection between the generation and/or

Storage of renewable energy not just the first gas-fired heater, but all energy-requiring components, for example mills, filters, conveyor belts,

compressors and the like.

In a further embodiment of the invention, the first gas flow heater has at least one inner surface. The energy input into the gas occurs exclusively via the inner surface. The inner surface can be, for example, the surface of a heating wire. Likewise, the inner surface can be a metallic surface which is electrically heated from the back. Likewise, the inner surface can be the surface of a body through which a heat exchange medium flows, in particular a pipe. The inner surface can also be the surface of a heated heat storage medium, for example masonry. An inner surface is therefore any surface that is arranged inside the first gas flow heater. This is fundamentally different from a burner where...

The combustion process uses the energy inside the gas stream and not via one

surface provides.

In a further embodiment of the invention, the first gas flow heater is a

Heat exchanger. This embodiment is preferred if the energy is generated using

Solar thermal energy, for example using molten salt, is obtained and provided. In this way, the thermal energy can be optimally used without conversion losses during previous electricity generation. In addition, appropriate solar thermal systems can also be used to temporarily store the warm

Heat exchange medium is known, especially at night and/or in the sun

to bridge the days.

In a further embodiment of the invention, the first gas flow heater is an electric gas flow heater. The gas stream is particularly preferred in just one

An annular gap is guided around an inner surface which is electrically heated. This means that the comparatively high temperatures required for the process are easier

to achieve shape. As an example, a heating element according to the

DE 10 2014 102 474 A1 mentioned as an example.

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In a further embodiment of the invention, the first gas flow heater is as

Tube bundle heating carried out. By designing it as a tube bundle, the inner

surface and thus the heat transfer can be increased. At the same time, the

Reducing the thickness of the gas layer accelerates the diffusion within the gas.

Next is the outer surface, which radiates heat and thus a

Heat loss and thus a decrease in temperature are reduced.

In a further embodiment of the invention is between the first

Gas flow heating and the thermal treatment device have a heat storage arranged. The heat storage can consist of a large mass through which flows.

For example, the heat storage can consist of wall material. The

Heat storage can also be made of metal. The heat storage serves in particular to equalize the temperature and can therefore be used over time

Fluctuations in the renewable energy generated and thus introduced into the process

Balance energy.

In a further embodiment of the invention is between the first

Gas flow heating and the thermal treatment device a gas-gas

Heat exchanger arranged. This becomes a primary fluid between the first

Gas flow heating and the gas-gas heat exchanger run in a circle. This will, for example, prevent dust from entering the first gas flow heater. Rather, an inert gas, for example nitrogen or argon, can be used as the primary fluid, which additionally causes corrosion, for example, at the hot spots of the first

Gas flow heating avoided. Gas-gas heat exchange is particularly preferred

Countercurrent heat exchanger executed. The primary fluid can be used after the first

Gas flow heating and the gas-gas heat exchanger, for example, have a temperature of 1400 ° C to 2000 ° C. zo In a further embodiment of the invention, in the gas flow direction in front of the

Drying device arranged a second gas flow heater. Due to the high

The enthalpy of vaporization of water in the drying device is high

Energy requirement, whereby the temperature can, for example, remain in a range below 400 °C. However, in other embodiments it may be advantageous to

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The temperature after the second gas flow heating should be chosen to be significantly hotter, so that it is in particular above 9800 ° C, for example at 1000 ° C to 1200 ° C. Due to the higher temperature, a smaller gas stream can be used, with the moisture content and the resulting evaporation causing the solid in the

Drying device itself is not brought to this temperature. But there the

Gas flow is intended to provide all the energy, for example to replace combustion and thus avoid CO2 emissions, the gas flow must be adjusted in terms of mass in order to be able to transport the required energy.

Therefore, targeted second heating in a second gas flow heater is advantageous.

In a further embodiment of the invention, the system has a third

Gas flow heating on. The third gas flow heater is gas-conducting with the thermal one

Treatment device connected. In particular, the third gas flow heater is arranged downstream of the first gas flow heater. For example, the gas supply from the first gas flow heater is arranged at the beginning of the thermal treatment device and the gas supply from the third gas flow heater is arranged approximately in the middle of the thermal treatment device. This can result in additional thermal

Energy will be made available after the first part from the first

The gases coming from the gas flow heater have cooled down due to the thermal treatment.

In a further embodiment of the invention, the first gas flow heater and an optional third gas flow heater are designed to fully provide the energy required in the thermal treatment device. The first

Gas electricity heating is therefore not just about supplying a partial amount, but it is about not just a combustion process through the first

Gas electricity heating is not supported, but the gas electricity heating is able to cover the entire energy requirement in regular operation. As an alternative, an additional one can be used

Heating element may be arranged inside the thermal treatment device. zo This offers advantages and disadvantages. A disadvantage is the possibility of the formation of

Temperature peaks when using a heating element in the thermal

Treatment device, which in turn can lead to deactivation of the material if certain temperature values are locally exceeded. The usage

/ BE2022/5544 using only the gas stream as an energy supplier, however, leads to an extremely uniform

Temperature profile within the thermal treatment device.

In a further embodiment of the invention, the thermal

Treatment device has a reserve burner. The reserve burner is used, for example, to be able to maintain emergency operation in the event of a failure of renewable energy, for example to safely shut down the system or to keep it at operating temperature for bridging purposes. However, the reserve burner is not intended for regular or continuous operation and is therefore not designed for this purpose.

In a further embodiment of the invention, the system has a material cooler. The material cooler serves to cool the mineral material and transfer the thermal energy to a gas stream. The thermal

The treatment device is connected to the material cooler to carry solids. The

Material cooler is gas-carrying with the first gas flow heater and the first

Gas flow heating is connected to the thermal treatment device in a gas-carrying manner. As a result, the thermal energy is recovered and used for the

Heating in the first gas flow heater reduces the amount of energy generated from renewable sources.

In a further embodiment of the invention, the system has a

Material pre-cooler. The material pre-cooler is preferably arranged along the material flow in front of the material cooler. The material cooler is used in particular for initial cooling as quickly as possible, for example to a temperature between 400 ° C and 500 ° C. This is preferred if color optimization of the product was carried out, for example in a reducing atmosphere, in order to avoid renewed oxidation and thus new discoloration of the product. For example, one can

Material cooler can be a solid-solid cooler in which the heat is not released into a gas stream. A corresponding cooling concept can be found, for example, in DE 10 2020 211 750 A1.

In a further embodiment of the invention, the system has a reducing

Reactor, in particular a reducing fluidized bed reactor. The

3 BE2022/5544 reducing reactor, in particular the reducing fluidized bed reactor, is usually used to optimize the color of the product under reducing conditions. The thermal treatment device is solid-conducting with the reducing

Fluidized bed reactor connected and the reducing fluidized bed reactor is connected to the material cooler in a solid-carrying manner.

In a further embodiment of the invention, the first gas flow heater or the heat storage downstream of the first gas flow heater is with the

Drying device connected to carry gas. This means that a partial gas stream becomes directly the

Drying device supplied.

In a further embodiment of the invention, the preheater or the

Drying device connected to the first gas flow heater in a gas-carrying manner. Such a circuit is particularly preferred if the gas is not air, but in particular if an inert gas or a reducing gas is used

Atmosphere is used. This allows the valuable gas to be reused.

In a further embodiment of the invention, the thermal

Treatment device has a surface heating element. Although this may involve the risk of local temperature spikes, in this way it is possible

Energy from a renewable energy source directly into the thermal one

To introduce the treatment device or to compensate for radiation losses and thus support the reaction and equalize the average temperature.

In a further embodiment of the invention, a gas connection is between the

Material cooler and the thermal treatment device arranged. In this way, comparatively cold gas can be supplied to the thermal treatment device and the temperature can be regulated easily and very quickly by mixing.

In a further embodiment of the invention, a gas connection is between the

Material cooler and the drying device arranged. This allows the

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Heat generated by material cooling in a simple and efficient manner for the

Drying can be used.

In a further embodiment of the invention, a gas connection is between the

Material cooler and the second gas flow heater arranged. This also allows the

Heat can be used to cool the material for drying.

In a further embodiment of the invention, a gas connection is between the

Material cooler and the third gas flow heater arranged.

In a further embodiment of the invention, a gas connection is between the

Drying device and the first gas flow heater arranged. As a result, the water vapor is introduced into the system, which in turn increases the thermal capacity, which in turn leads to a smaller drop in the temperature within the thermal treatment device.

In a further embodiment of the invention, a gas connection is between the

Drying device and the third gas flow heater arranged. As a result, the water vapor is introduced into the system, which in turn increases the thermal capacity, which in turn leads to a smaller drop in the temperature within the thermal treatment device.

In a further embodiment of the invention, a dust filter is arranged in front of the first gas flow heater.

In a further aspect, the invention relates to a method for thermal

Activation of fine-grained mineral raw materials to produce artificial pozzolans, in particular for a system according to the invention. As is usual in the prior art, the material flow is passed through a preheater and through a thermal treatment device. What is essential to the invention is that the gas stream in front of the

Supply to the thermal treatment device is heated in the first gas flow heater. The energy for the process in the thermal treatment device is therefore not generated and provided in the thermal treatment device by combustion, but before entering the thermal

Treatment device is impressed on the gas flow in the first gas flow heater and introduced into the thermal treatment device by the gas flow. This makes it easy to rely entirely on renewable energy and thus avoid CO2 emissions for energy production and thus make the production of artificial pozzolans climate-neutral.

In a further embodiment of the invention, the gas stream is in the first

Gas stream heating to 800 ° C to 1800 ° C, preferably to 800 ° C to 1600 ° C, preferably to 800 ° C to 1400 ° C, preferably to 800 ° C to 1200 ° C, most preferably to 1000 ° C to 1200 ° C , heated.

In a further embodiment of the invention, it is used as a fine-grained mineral

Raw materials a natural clay, pure or as a mixture, a clay-like substance

Zeolite, waste cement stone or a mixture selected.

In a further embodiment of the invention, the gas in the first

Gas flow heater heated over an inner surface of the first gas flow heater.

In a further embodiment of the invention, a further gas stream is supplied to the drying device. The further gas stream is in a second

Gas flow heater heated. In this way it can be achieved that also for the

Drying device in a simple manner sufficient energy on the right

temperature level is available.

In a further embodiment of the invention, the thermal

An additional gas stream is supplied to the treatment device. The additional gas stream is heated in a third gas stream heater. This enables the addition of a second one

Gas stream, for example in the middle of the thermal treatment device.

This means that hotter gas can be supplied there again and thus the thermal gas can be supplied in a targeted manner

Activation can be controlled/influenced and/or the temperature profile can be evened out via the thermal treatment device.

In a further embodiment of the invention, the first gas flow heater and an optional third gas flow heater provide the entire thermal

Treatment device required energy ready. This makes it possible to dispense with a heating element arranged in the thermal treatment device.

In a further embodiment of the invention, in the event of a failure

Energy supply and thus a reserve burner for the first gas flow heater

Generation of thermal energy used in the thermal treatment device.

This can bridge outages or ensure a safe shutdown. However, using the reserve burner is only for such

Exceptional situations provided.

In a further embodiment of the invention, the gas stream coming from a material cooler is heated in the first gas stream heater. This allows the

Waste heat from the material flow can be used efficiently and thus also

Energy requirements of the first gas flow heater can be reduced.

In a further aspect, the invention relates to a control method, wherein the gas temperature emerging from the first gas flow heater is measured and wherein the gas flow supplied to the first gas flow heater and the electrical energy supplied to the first gas flow heater are regulated depending on the measured gas temperature. The regulation is particularly preferably carried out in such a way that the

Available electrical energy (from the amount of energy currently generated and, for example, the remaining charge of a battery storage) is taken into account.

Particular preference is also given to the amount of solids supplied to the system

Dependence of the available electrical energy (from the amount of energy currently generated and, for example, the remaining charge of a battery storage system). For example, if energy production falls, for example at night with a solar system or with a lull in the wind with a wind turbine, it will

Utilization of the system adjusted accordingly. The system according to the invention is explained in more detail below using the exemplary embodiments shown in the drawings.

Fig. 1 first exemplary embodiment

Fig. 2 second exemplary embodiment

Fig. 3 third exemplary embodiment

Fig. 4 fourth exemplary embodiment

Fig. 5 fifth exemplary embodiment

Fig. 6 sixth exemplary embodiment

Fig. 7 seventh exemplary embodiment

Fig. 8 eighth exemplary embodiment

Fig. 9 ninth exemplary embodiment

Fig. 10 tenth exemplary embodiment

Fig. 11 eleventh exemplary embodiment

Fig. 12 _twelfth exemplary embodiment

The same components are given the same reference numerals in the following

To simplify comparability across the different embodiments.

A first exemplary embodiment is shown in FIG. Appendix 10 has one

Mill 110, in which, for example, clay is ground as a starting product. From there, the solids stream is transferred to the drying device 20 and dried there. From there the solids stream is transferred to the thermal via the preheater 30

Treatment device 40 guided and then guided into a material cooler 100. In the material cooler 100, the solids stream is cooled with a gas stream and the gas stream is thereby warmed up. The preheated gas stream is led from the material cooler 100 into the first gas stream heater 50 and heated there, in particular electrically, to, for example, 1200 ° C. For this purpose, it is particularly preferred to use electricity generated from renewable sources, in particular from a mix of solar and wind power. This means that fossil fuels can be completely avoided and the production of artificial pozzolans can be made climate-neutral. The gas stream is led from the first gas stream heater 50 into the thermal treatment device 40 and provides the energy required for the treatment there.

The gas stream is then led from the thermal treatment device 40 into the preheater and from the preheater 30 into the drying device 20.

Only the differences between the individual embodiments will be discussed below.

Fig. 2 shows a second embodiment, in which, in contrast to the first embodiment shown in Fig. 1, there is also a heat storage 60 between the first gas heater 50 and the thermal treatment device 40. For example, this can be a brick area. This creates a

Temperature comparison is achieved, even if, for example, the regeneratively generated electricity, which is used for the electrical heating in the first gas flow heater 50, has fluctuations.

A third embodiment is shown in FIG.

This allows the energy requirement to be specifically adjusted to the energy required for drying via the amount of gas flow and temperature. In return he will

Gas stream from the preheater 30 is discarded. Alternatively, the gas stream can come from the

Preheater 30 can also be supplied to the second gas flow heater 70.

Fig. 4 shows a fourth embodiment, in which, in contrast to the first embodiment shown in Fig. 1, a third gas flow heater 80 is present. The third

Gas flow heater 80 heats a gas flow that is approximately in the middle of the thermal

Treatment device 40 is supplied. Since in the thermal

Treatment device 40 has no direct internal heating, which is used for the

Energy required for solid conversion is taken from the gas stream, which then cools down. By supplying the gas stream from the third gas stream heater 80, a hot gas stream is again supplied and thus the temperature is above the thermal one

Treatment device 40 is evened out.

Fig. 5 shows a fifth embodiment, in which, in contrast to the first embodiment shown in Fig. 1, a reducing fluidized bed reactor 120, which is arranged between the thermal treatment device 40 and the material cooler 100. In the reducing fluidized bed reactor 120, in a reducing

Atmosphere color optimization was carried out, for example in one

Hydrogen, carbon monoxide, hydrocarbon or a gas mixture containing these

Has substances or is made from them, having atmosphere. For this purpose, a suitable reducing agent is supplied to the reducing fluidized bed reactor 120 accordingly. By separating the gas stream from material cooler 100, thermal treatment device 40 and preheater with an oxygen-containing atmosphere from the reducing atmosphere in the reducing

Fluidized bed reactor 120 can significantly save on reducing medium.

Fig. 6 shows a sixth embodiment, in which, in contrast to the third embodiment shown in Fig. 3, the gas stream after the preheater 30 is optionally fed to the material cooler 100 via a cooling device, not shown. This enables the use of a reducing atmosphere in the thermal

Treatment device 40. In order to be able to separate gas products emerging from the clay, the gas connection between the preheater 30 and the material cooler 100 has a gas flow divider, not shown, in order to separate a partial gas stream and thus prevent enrichment of the gas products emerging from the clay.

Fig. 7 showed a seventh embodiment, in which, in contrast to the first embodiment shown in Fig. 1, additional gas connections are present. From the

Material cooler 100 has gas connections to the thermal treatment device 40 and to the drying device 20. In addition, warm air can also be delivered elsewhere

Location of Appendix 10 can be used. Furthermore, there is also a returning one

Gas connection from the drying device 20 to the material cooler 100 is present.

These additional gas connections are also on the second through sixth

Embodiment applicable analogously.

The eighth embodiment shown in Fig. 8 is a combination of the third embodiment shown in Fig. 3 and the seventh embodiment shown in Fig. 7

Embodiment is particularly important in the eighth embodiment

Gas connection from the preheater 30 to the second gas flow heater.

The ninth embodiment shown in Fig. 9 represents a combination of the fifth embodiment shown in Fig. 5zo and the seventh embodiment shown in Fig. 7

Embodiment. The material pre-cooler 130 is particularly important. A cold material stream is led to this from the material cooler 100, whereby via a

Solid-solid heat transfer efficiently lowers the temperature quickly and a

Discoloration can be prevented. A corresponding material precooler 130 can be found, for example, in DE 10 2020 211 750 A1.

Fig. 10 shows a tenth embodiment different from the ninth shown in Fig. 9

Embodiment differs in that it does not have a reducing effect

Fluidized bed reactor 120. Rather, the treatment takes place thermally

Treatment device 40 is already in a reducing atmosphere, which is why in particular the gas connection from the drying device 20 to the

Material cooler 100 is important. In a further alternative embodiment, in addition to or instead of this gas connection, a gas connection between the

Preheater and the material cooler 100 and / or the first gas flow heater can be arranged in order to be able to circulate the reducing atmosphere.

The eleventh embodiment shown in Fig. 11 differs from the eighth embodiment shown in Fig. 8 by additional gas connections

Preheater 30 to the first gas flow heater 50 and from the drying device 20 to the first gas flow heater 50. In addition, there is a further gas connection between the

Drying device 20 and the second gas flow heater 70 are arranged.

The twelfth embodiment shown in FIG. 12 differs from the seventh embodiment shown in FIG. 7 in that the first gas flow heater 50 is not arranged directly in the gas flow, but rather in a circuit with a gas flow.

Gas heat exchanger 140 is arranged so that the heating surfaces are in the first

Gas flow heater 50 does not come into contact with dust or corrosive gas compounds. This allows the lifespan of the first gas flow heater to be extended. The gas-gas heat exchanger is particularly preferred

Countercurrent heat exchanger designed.

Reference number zo 10 system 20 drying device

Preheater thermal treatment device first gas flow heater

60 heat storage 70 second gas flow heater 80 third gas flow heater 100 material cooler 110 mill 120 reducing fluidized bed reactor 130 material precooler 140 gas-gas heat exchanger

Claims (26)

Expectations 1. Plant (10) for the thermal activation of fine-grained mineral raw materials to produce artificial pozzolans, the plant (10) having a drying device (20), a preheater (30), a preheater (30) and a thermal treatment device (40), wherein the fine-grained mineral raw material is fed from the drying device (20) via the preheater (30) to the thermal treatment device (40), a gas stream being fed to the thermal treatment device (40) and fed from the thermal treatment device (40) to the preheater (30). , characterized in that a first gas flow heater (50) is arranged along the gas flow in front of the thermal treatment device (40). 2. Plant (10) according to claim 1, characterized in that the fine-grained mineral raw material is a natural clay, pure or as a mixture, a clay-like substance, a zeolite, waste cement stone or a mixture thereof. 3. Plant (10) according to one of the preceding claims, characterized in that the first gas flow heater (50) has at least one inner surface, with the energy input into the gas taking place exclusively via the inner surface. 4. Plant (10) according to one of the preceding claims, characterized in that the first gas flow heater (50) is a heat exchanger. 5. Plant (10) according to one of claims 1 to 2, characterized in that the first gas flow heater (50) is an electric gas flow heater. 6. Plant (10) according to one of the preceding claims, characterized in that the first gas flow heater (50) is designed as a tube bundle heater. 7. Plant (10) according to one of the preceding claims, characterized in that a heat accumulator (60) is arranged between the first gas flow heater (50) and the thermal treatment device (40). 8. Plant (10) according to one of the preceding claims, characterized in that a gas-gas heat exchanger (140) is arranged between the first gas flow heater (50) and the thermal treatment device (40). 9. Plant (10) according to one of the preceding claims, characterized in that a second gas flow heater (70) is arranged in the gas flow direction in front of the drying device (20). 10.System (10) according to one of the preceding claims, characterized in that the system (10) has a third gas flow heater (80), the third gas flow heater being connected to the thermal treatment device (40) in a gas-carrying manner. 11.System (10) according to one of the preceding claims, characterized in that the first gas flow heater (50) and an optional third gas flow heater (80) are designed to completely provide the energy required in the thermal treatment device (40). 12.Plant (10) according to one of the preceding claims, characterized in that the thermal treatment device (40) has a reserve burner. 13.Plant (10) according to one of the preceding claims, characterized in that the plant (10) has a material cooler (100), the thermal treatment device (40) being connected to the material cooler (100) in a solid-carrying manner, the material cooler (100) is connected in a gas-carrying manner to the first gas flow heater (50) and the first gas flow heater (50) is connected in a gas-carrying manner to the thermal treatment device (40). 14. Plant (10) according to claim 13, characterized in that the plant (10) has a reducing reactor, in particular a reducing fluidized bed reactor (120), wherein the thermal treatment device (40) carries solids with the reducing reactor, in particular the reducing fluidized bed reactor (120), is connected, wherein the reducing reactor, in particular the reducing fluidized bed reactor (120), is connected to the material cooler (100) in a solid-carrying manner. 15.System (10) according to one of the preceding claims, characterized in that the first gas flow heater (50) or the heat storage (60) downstream of the first gas flow heater (50) is connected to the drying device (20) in a gas-carrying manner. 16.System (10) according to one of the preceding claims, characterized in that the preheater (30) or the drying device (20) is connected to the first gas flow heater (50) in a gas-carrying manner. 17.System (10) according to one of the preceding claims, characterized in that the thermal treatment device (40) has a surface heating element. 18. Process for the thermal activation of fine-grained mineral raw materials to produce artificial pozzolans, the material stream being passed over a preheater (30) and through a thermal treatment device (40), the gas stream being heated in the first gas stream heater before being fed to the thermal treatment device (40). (50) is heated. 19. The method according to claim 18, characterized in that the gas stream in the first gas stream heater (50) is heated to 800 ° C to 1800 ° C, preferably to 1000 ° C to 1200 ° C. 20. The method according to any one of claims 18 to 19, characterized in that a natural clay, pure or as a mixture, a clay-like substance, a zeolite, waste cement stone or a mixture is selected as the fine-grained mineral raw materials. 21. The method according to any one of claims 18 to 20, characterized in that the gas in the first gas flow heater (50) is heated via an inner surface of the first gas flow heater (50). 22. The method according to any one of claims 18 to 21, characterized in that the drying device (20) is supplied with a further gas stream, the further gas stream being heated in a second gas stream heater (70). 23. The method according to any one of claims 18 to 22, characterized in that the thermal treatment device (40) is supplied with an additional gas stream, the additional gas stream being heated in a third gas stream heater (80). 24 Method according to one of claims 18 to 23, characterized in that the first gas flow heater (50) and an optional third gas flow heater (80) provide all of the energy required in the thermal treatment device (40). 25. The method according to any one of claims 18 to 24, characterized in that in the event of a power supply failure, a reserve burner is used to generate thermal energy in the thermal treatment device (40). 26. The method according to any one of claims 18 to 25, characterized in that the gas stream coming from a material cooler is heated in the first gas stream heater (50).