Reactor for chemical process engineering

Abstract

A device (1) for carrying out at least one chemical process, the device (1) comprising: a reactor (10) having a reactor housing (11) defining a reactor chamber (12) and configured to carry out the at least one chemical process; wherein the reactor housing (11) has at least one resistance-heated section (18) designed as an electrical resistance heater for heating the reactor chamber (12).

Description

[0001] The present invention relates to a device having a reactor for carrying out at least one chemical process.

[0002] In many areas of chemical process engineering, reactors, catalysts, heat exchangers, and evaporators are used to split or synthesize substances. A basic principle of such systems is based on the spatial separation of material flows and the transfer of thermal energy through the reactor structure. High temperatures, possibly elevated pressures, and a catalyst are often required to activate these processes.

[0003] The materials used must meet stringent requirements regarding corrosion resistance and chemical resistance at high temperatures and under the influence of the starting materials and reaction products. If heating is performed with a burner, resistance to an oxidizing atmosphere is also required.

[0004] To activate and maintain endothermic processes, heat energy must be supplied, for example through electrical heating or a burner.

[0005] In all cases, heat transfer occurs through conduction and, where appropriate, radiation. This is inherently subject to losses, whether through conduction losses (in the case of external burners) and / or through heat transfer losses (in the case of indirect electrical heating in an electrically heated furnace environment).

[0006] While integrated gas burners for heat generation can reduce line losses, they increase system complexity. Difficult access may also increase maintenance costs and thus system downtime in the event of a failure.

[0007] A main requirement for heating a reaction chamber is therefore to achieve an adapted heat transfer performance with the highest possible efficiency and the lowest possible heat losses.

[0008] In many chemical processes, heat is supplied by gas burners or electric heating. Reactor systems often comprise a furnace with a pipe system that carries the starting media and reaction products through the furnace. In the case of catalytically supported processes, the pipe system may contain beds of catalytically coated material.

[0009] The Fig. Figure 1 shows such a reactor system 100, which comprises a furnace 110 and a pipe system 120 arranged at least partially therein. The furnace 110 is heated by an electric heater 111.

[0010] The pipe system 120 is embodied, for example, as a double pipe, comprising a reactant section 121 through which a reactant E or reactant is guided into and through the furnace 110 on one side, and a product section 122 through which, following the chemical process, the product P is guided through and out of the furnace 110 on the same side. The reactant section 121 and the product section 122 are embodied as a pipe-in-pipe design. Alternatively, a design is possible in which the pipe system 120 is embodied as a single pipe, and the reactant section 121 and the product section 122 are guided out of the furnace 110 on opposite sides.

[0011] In the lower region of the reactant section 121, a catalyst K is introduced as a bed of catalytic material. In this way, the reactor system 100 is divided into a heat exchanger section 101 and a catalyst section 102.

[0012] Depending on the external thermal insulation, more or less large heat losses occur via the outer wall of the furnace 110.

[0013] The Fig. 1 shows only one pipe system 120, however, several pipe systems 120 can be installed in the furnace 110. Within the furnace 110, the individual pipe systems 120 or reactor tubes are to be supplied with as equal heat flows as possible to ensure equal conversion rates. Therefore, both in the case of convective heating by hot gas and in the case of the Fig. For the electric heating shown in Figure 1, a minimum distance between the pipe systems 120 is required to achieve the most uniform flow of hot gas around the pipes and to transfer the radiant heat from electric heaters 111 as evenly as possible to the individual pipes. This means that the furnace volume must be significantly larger than the pipe volume, which limits the power density.

[0014] An object of the invention is to provide an improved device with a reactor for carrying out a chemical process.

[0015] The object is achieved by a device having the features of claim 1. Advantageous further developments follow from the subclaims, the following presentation of the invention and the description of preferred embodiments.

[0016] The device according to the invention serves to carry out at least one chemical process. The device is used in chemical process engineering, for example, for the splitting, synthesizing, or other production or conversion of substances.

[0017] The device comprises a reactor having a reactor housing defining a reactor space and configured to carry out the at least one chemical process.

[0018] According to the invention, the reactor housing has at least one resistance-heated section designed as an electrical resistance heater for heating the reactor chamber. In other words, heating of the reactor chamber is achieved by integrating the heating function into the geometry forming the reactor chamber, i.e., by integrating the heating function into the reactor housing.

[0019] Compared to furnace systems operated with gas burners or electric heaters, the device designed in this way enables a reduction in the volume to be heated by directly heating the reactor chamber. This results in a reduction in the external surface area and in heat loss. The device enables particularly high power density and control dynamics, i.e., rapid power adjustment, with a small installation space requirement, thus enabling a wide scalability range and, in particular, small sizes. This also results in a comparatively low weight of the device, which is particularly advantageous in non-stationary applications.

[0020] A further technical contribution of the device is its high efficiency by reducing heat losses due to a small external surface.

[0021] The device enables a modular design that allows scaling for a wide range of performance.

[0022] The compact design of the device, achieved through the synergistic use of the reactor housing as a resistance heater, results in a reduction in manufacturing costs as well as operating costs and resource consumption due to lower energy requirements for the activation and maintenance of endothermic processes.

[0023] Preferably, the reactor is designed as a flow-through tube or as a flow-through double tube or tube-in-tube concept, which allows the device to be realized in a particularly compact mechanical design.

[0024] The reactor preferably comprises a reactant section through which a reactant can be fed into and at least partially through the reactor, and a product section through which a product can be fed at least partially through and out of the reactor following the at least one chemical process. In this way, a continuous process can be carried out in a compact reactor design.

[0025] A catalyst may be provided in the reactor chamber to carry out and / or support at least one chemical process.

[0026] The catalyst can, for example, be implemented as a bed of a catalytic material and / or a catalytically coated material. Alternatively or additionally, the reactor chamber can be provided with a catalytic coating.

[0027] Preferably, the reactor has two electrical connections connected to the reactor housing and configured to supply electrical power to the reactor housing, with the resistance-heated section arranged between the two connections. In this way, the reactor housing can be directly connected to a power supply.

[0028] Preferably, an electrical insulator is installed on each side of the electrical connections opposite the resistance-heated section. The electrical insulators can be located directly adjacent to the electrical connections or further outward, thereby electrically isolating any areas of the reactor not to be heated from the resistance-heated section.

[0029] Preferably, at least the resistance-heated section of the reactor housing is made of reaction-bonded silicon-infiltrated silicon carbide. This allows for rapid heating due to the thermal-mechanical material properties of SiSiC and thus a short start-up delay, enabling the device to be used, for example, in cyclically operated systems. The device also exhibits high corrosion resistance to a wide variety of media, particularly to the influence of water vapor, ammonia, hydrogen, and nitrogen.

[0030] Preferably, the reactor is manufactured by means of continuous casting, slip casting or an additive process, which allows the device to be manufactured structurally simply and reliably.

[0031] The resistance-heated section of the reactor chamber preferably contains a honeycomb body, preferably an extruded honeycomb body, an alternative geometric structure with a raised surface, in particular ribs, and / or a filling, in particular a ceramic bed. In this way, the heat transfer surface in the reactor chamber can be increased.

[0032] Preferably, the device comprises thermal insulation that at least partially surrounds the reactor, in particular the resistance-heated section, thereby achieving the principle of a hot reactor core with a temperature level decreasing towards the outside. Since the heat is generated in the reactor core or reactor chamber itself, no introduction losses occur due to a heat flow supplied from the outside.

[0033] Further advantages and features of the present invention will become apparent from the following description of preferred embodiments. The features described therein can be implemented alone or in combination with one or more of the features presented above, provided the features do not contradict each other. The following description of preferred embodiments is provided with reference to the accompanying drawings. Short description of the characters

[0034] Preferred further embodiments of the invention are explained in more detail in the following description of the figures. In the figures: Fig. 1 schematically shows a conventional reactor system with an electrically heated furnace and a pipe system; Fig. 2 schematically shows an apparatus for carrying out a chemical process with a resistance-heated reactor according to an embodiment; Fig. 3 is a sectional perspective view of an apparatus for carrying out a chemical process according to a further embodiment; Fig. 4 schematically shows an apparatus for carrying out a chemical process according to a further embodiment. Detailed description of preferred embodiments

[0035] Preferred embodiments are described below with reference to the figures. Identical, similar, or equivalent elements are provided with identical reference numerals in the figures, and a repeated description of these elements is partially omitted to avoid redundancy.

[0036] The Fig. Figure 2 shows a device 1 for carrying out a chemical process, which device comprises a resistance-heated reactor 10. The device 1 is used in chemical process engineering, for example for the splitting, synthesizing, or other production or conversion of substances.

[0037] In this case, the reactor 10 has the shape of a simple flow-through tube. However, other geometries are also possible, for example a double-tube design or a tube-in-tube design similar to that of the Fig. 1. The reactor 10 has a reactor housing 11 which has a reactor chamber 12 (cf. Fig. 3). In the case of a tubular design of the reactor 10, the reactor housing 11 is realized by the (hollow cylindrical) tube wall.

[0038] The reactor 10 comprises a reactant section 13, through which a reactant E or reactant is passed into and at least partially through the reactor 10, and a product section 14, through which a product P is passed through and out of the reactor 10 following a chemical process.

[0039] A catalyst 15 can be provided in the reactor chamber 12 to carry out the chemical process. The catalyst 15 can, for example, be designed as a bed of a catalytic material and / or a catalytically coated material. Alternatively or additionally, the reactor chamber 12 can be provided with a catalytic coating.

[0040] The goal of heating the reactor chamber 12 with minimal heat loss is achieved by integrating the heating function into the geometry forming the reactor chamber 12. In other words, the reactor geometry itself, i.e., the reactor housing 11, is designed, at least in sections, as an electrical resistance heater.

[0041] The principle of integrated resistance heating is in the Fig. 2 in the form of a simple geometric variant of the flow-through tube. The reactor 10 has two electrical connections 16, 17 connected to the reactor housing 11, whereby the reactor housing 11 can be directly supplied with electrical power. At least the central region of the reactor housing 11 between the two electrical connections 16, 17, also referred to herein as the resistance-heated section 18, is made of a material suitable for converting the electrical energy provided by the connections 16, 17 into thermal energy.

[0042] An electrical insulator 19 may be installed immediately adjacent to the electrical terminals 16, 17 (on the side opposite the resistance heated section 18) or further out.

[0043] Such resistance heating of the reactor geometry significantly reduces the heated volume compared to, for example, a reactor tube heated in a combustion chamber or furnace. Further efficiency benefits result from minimizing heat loss surfaces and improving heat transfer. The reduced energy requirement results in lower operating costs.

[0044] The integration of the electrical resistance heating function into the reactor geometry or reactor housing 11 imposes special material requirements. High temperature resistance, high strength at high temperatures, and high thermal shock resistance are required or desired, as are high HT corrosion resistance and a suitable specific electrical resistivity. To ensure tightness, the material of the reactor housing 11 should be pore-free.

[0045] The required or desired material properties of reactor 10 are met in particular by reaction-bonded silicon-infiltrated silicon carbide (SiSiC). Shaping can be achieved using ceramic forming processes, such as continuous casting or slip casting, as well as additive processes (3D printing), thus resulting in a wide range of geometrical degrees of freedom for reactor 10.

[0046] In order to increase the heat transfer surface in the reactor chamber 12, the resistance-heated section 18 can comprise an extruded honeycomb body 20, as in the embodiment of the Fig. 3, or another geometric structure with a raised surface (e.g., fins). The heat transfer surface can also be increased by filling it with a ceramic bed.

[0047] The resistance-heated reactor 10 can be combined with a thermal insulation 30, see embodiment of the Fig.4, thereby achieving the principle of a hot reactor core with a temperature level decreasing towards the outside. Since the heat is generated in the reactor core or reactor chamber 12 itself, there are no losses due to the introduction of a heat flow supplied from the outside.

[0048] Compared to furnace systems operated with gas burners or electric heaters, the devices 1 described above enable a reduction in the volume to be heated by directly heating the reactor chamber 12. This results in a reduction in the external surface area and in the loss of heat. The device 1 enables a particularly high power density and control dynamics, i.e., rapid power adjustment, with a small installation space requirement, thus enabling a wide scalability range and, in particular, small sizes.

[0049] Further technical contributions of device 1 include high efficiency through reduced heat losses due to a small external surface area, rapid heating due to the thermal-mechanical material properties, particularly of SiSiC, and thus a short switch-on delay, which enables its use, for example, in cyclically operated systems. Furthermore, device 1 is comparatively lightweight, particularly due to the use of SiSiC, which is particularly advantageous in non-stationary applications. Device 1 exhibits high corrosion resistance against a variety of media, in particular against the influence of water vapor, ammonia, hydrogen, and nitrogen.

[0050] The device 1 enables a modular design, which allows scaling for a wide range of performance.

[0051] The compact design of the device 1 and the synergistic use of the reactor housing 11 as a resistance heater result in a reduction in manufacturing costs as well as operating costs and resource consumption due to lower energy requirements for the activation and maintenance of endothermic processes.

[0052] Where applicable, all individual features presented in the embodiments may be combined and / or exchanged without departing from the scope of the invention. List of reference symbols 1 device for carrying out a chemical process 10 reactor 11 Reactor casing 12 reactor room 13 Educt section 14 Product section 15 Catalyst 16 Electrical connection 17 Electrical connection 18 Resistance heated section 19 Insulator 20 honeycomb bodies 30 Thermal insulation 100 reactor system 101 Heat exchanger section 102 Catalyst section 110 Oven 111 Electric heating 120 pipe system 121 Educt section 122 Product section E reactant P Product K catalyst

Claims

[1] Device (1) for carrying out at least one chemical process, the device (1) comprising: a reactor (10) having a reactor housing (11) defining a reactor chamber (12) and configured to carry out the at least one chemical process; wherein the reactor housing (11) has at least one resistance-heated section (18) for heating the reactor chamber (12), which is designed as an electrical resistance heater. [2] Device (1) according to claim 1, characterized by that the reactor (10) is designed as a flow-through tube, double tube or tube-in-tube concept. [3] Device (1) according to claim 1 or 2, characterized byin that the reactor (10) has a reactant section (13) through which a reactant (E) can be guided into and at least partially through the reactor (10), and a product section (14) through which a product (P) can be guided at least partially through and out of the reactor (10) following the at least one chemical process. [4] Device (1) according to one of the preceding claims, characterized by that a catalyst (15) is provided in the reactor chamber (12). [5] Device (1) according to claim 4, characterized by that the catalyst (15) is realized as beds of a catalytic material and / or a catalytically coated material and / or in that the reactor space (12) is provided with a catalytic coating. [6] Device (1) according to one of the preceding claims, characterized bythat the reactor (10) has two electrical connections (16, 17) which are connected to the reactor housing (11) and are designed to supply the reactor housing (11) with electrical power, wherein the resistance-heated section (18) is arranged between the two connections (16, 17). [7] Device (1) according to claim 6, characterized by that an electrical insulator (19) is installed on each side of the electrical connections (16, 17) opposite the resistance-heated section (18). [8] Device (1) according to one of the preceding claims, characterized by that at least the resistance-heated section (18) is made of reaction-bonded silicon-infiltrated silicon carbide. [9] Device (1) according to one of the preceding claims, characterized by that the reactor (10) is manufactured by means of continuous casting, slip casting or an additive process. [10] Device (1) according to one of the preceding claims, characterized by that the resistance-heated section (18) of the reactor chamber (12) contains a honeycomb body (20), preferably an extruded honeycomb body (20), an alternative geometric structure with a raised surface, preferably ribs, and / or a filling, preferably a ceramic bed. [11] Device (1) according to one of the preceding claims, characterized by that the device (1) has a thermal insulation (30) which at least partially surrounds the reactor (10), preferably the resistance-heated section (18).

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