Reactor for chemical process technology

Abstract

The invention relates to a device (1) for carrying out at least one chemical process, wherein the device (1) comprises: a reactor (10) which has a reactor housing (11) defining a reactor chamber (12) and is designed 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), said section being designed as an electrical resistance heater.

Description

[0001] Description

[0002] Reactor for chemical process engineering

[0003] The present invention relates to a device with a reactor for carrying out at least one chemical process.

[0004] Reactors, catalysts, heat exchangers, and evaporators are used in many areas of chemical process engineering 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.

[0005] 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.

[0006] To activate and maintain endothermic processes, heat energy must be supplied, for example by electrical heating or a burner.

[0007] In all cases, heat transfer takes place in the form of heat conduction and, where appropriate, heat radiation. This is generally subject to losses, either through conduction losses (in the case of external burners) and / or through

[0008] Heat transfer losses (in the case of indirect electrical heating in an electrically heated furnace environment). 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.

[0009] 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.

[0010] 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.

[0011] 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 means of an electric heater 111.

[0012] The pipe system 120 is designed, for example, as a double pipe, comprising a reactant section 121, through which a reactant E or reactant is passed into and through the furnace 110 on one side, and a product section 122, through which the product P is passed through after the chemical process and out of the furnace 110 on the same side. The reactant section 121 and the product section 122 are designed as a pipe-in-pipe construction. Alternatively, a construction is possible in which the pipe system 120 is designed as a single pipe and the reactant section 121 and the product section 122 are passed out of the furnace 110 on opposite sides. In the lower region of the reactant section 121, a catalyst K is introduced as a bed of a catalytic material. In this way, the reactor system 100 is divided into a heat exchanger section 101 and a catalyst section 102.

[0013] Depending on the external thermal insulation, more or less large heat losses occur across the outer wall of the furnace 110.

[0014] Figure 1 shows only one pipe system 120, although several pipe systems 120 can be installed in the furnace 110. Within the furnace 110, the individual pipe systems 120 or reactor tubes must be supplied with heat flows that are as equal as possible in order to ensure equal conversion rates. Therefore, both in the case of convective heating by hot gas and in the case of the electrical heating shown in Figure 1, a minimum distance between the pipe systems 120 is required in order to achieve the most even flow around the tubes with hot gas and to transfer the radiant heat from electrical heaters 111 as evenly as possible to the individual tubes. It follows that the furnace volume must be significantly larger than the tube volume, which limits the power density.

[0015] An object of the invention is to provide an improved device with a reactor for carrying out a chemical process.

[0016] This object is achieved by a device having the features of claim 1. Advantageous further developments follow from the subclaims, the following description of the invention, and the description of preferred embodiments.

[0017] 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.

[0018] The device comprises a reactor having a reactor housing defining a reactor space and being configured to carry out the at least one chemical process.

[0019] 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, the 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.

[0020] 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 losses. 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 installation sizes. This also results in a comparatively low weight of the device, which is particularly advantageous in non-stationary applications.

[0021] A further technical contribution of the device is its high efficiency by reducing heat losses due to a small external surface.

[0022] The device enables a modular design, allowing scaling across a wide power spectrum. 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 activating and maintaining 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, whereby the device can 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, following the at least one chemical process, a product can be fed at least partially through and out of the reactor. 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] The reactor preferably has two electrical connections which are connected to the reactor housing and are configured to supply the reactor housing with electrical power, the resistance-heated section being arranged between the two connections. In this way, the reactor housing can be directly connected to a power supply. Preferably, an electrical insulator is installed on each side of the electrical connections opposite the resistance-heated section. The electrical insulators can be provided directly next to the electrical connections or further outwards, whereby any areas of the reactor which are not to be heated are electrically insulated from the resistance-heated section.

[0028] 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 switch-on 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 effects of water vapor, ammonia, hydrogen, and nitrogen.

[0029] Preferably, the reactor is manufactured by means of continuous casting, slip casting or an additive process, whereby the device can be manufactured in a structurally simple and reliable manner.

[0030] 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 area in the reactor chamber can be increased.

[0031] 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 toward 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.

[0032] 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 set forth above, provided the features do not contradict one another. The following description of preferred embodiments is made with reference to the accompanying drawings.

[0033] Short description of the characters

[0034] Preferred further embodiments of the invention are explained in more detail by the following description of the figures. In the figures:

[0035] Figure 1 schematically shows a conventional reactor system with an electrically heated furnace and a pipe system;

[0036] Figure 2 shows schematically an apparatus for carrying out a chemical process with a resistance-heated reactor according to an embodiment;

[0037] Figure 3 is a sectional, perspective view of an apparatus for carrying out a chemical process according to a further embodiment;

[0038] Figure 4 schematically shows an apparatus for carrying out a chemical process according to a further embodiment.

[0039] Detailed description of preferred embodiments

[0040] Preferred embodiments are described below with reference to the figures. Identical, similar, or equivalent elements in the figures are provided with identical reference symbols, and a repeated description of these elements is partially omitted to avoid redundancy.

[0041] 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.

[0042] In the present case, the reactor 10 has the shape of a simple flow-through tube. However, other geometries, such as a double-tube design or a tube-in-tube design similar to that shown in Figure 1, are also conceivable. The reactor 10 has a reactor housing 11 that defines a reactor chamber 12 (cf. Figure 3). In the case of a tube design of the reactor 10, the reactor housing 11 is realized by the (hollow-cylindrical) tube wall.

[0043] 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.

[0044] 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.

[0045] The goal of minimizing heat loss in the reactor chamber 12 is achieved by integrating the heating function into the geometry forming the reactor chamber 12. In other words, the reactor geometry itself, ie, the reactor housing 11, is designed, at least in sections, as an electrical resistance heater.

[0046] The principle of integrated resistance heating is illustrated in Figure 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.

[0047] 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.

[0048] 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.

[0049] The integration of the electrical resistance heating function into the reactor geometry or the 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 resistance. To ensure tightness, the material of the reactor housing 11 should be pore-free.

[0050] The required or desired material properties of the reactor 10 are met in particular by reaction-bonded silicon-infiltrated silicon carbide (SiSiC). Shaping can be achieved by ceramic forming processes, such as continuous casting or slip casting, as well as by additive processes (3D printing), thus resulting in a broad spectrum of geometrical degrees of freedom for the reactor 10.

[0051] To increase the heat transfer area in the reactor chamber 12, the resistance-heated section 18 can comprise an extruded honeycomb body 20, as shown in the exemplary embodiment of Figure 3, or another geometric structure with a raised surface (for example, fins). The heat transfer area can also be increased by filling it with a ceramic bed.

[0052] The resistance-heated reactor 10 can be combined with thermal insulation 30, see the exemplary embodiment in Figure 4, thereby achieving the principle of a hot reactor core with a temperature level decreasing toward the outside. Since the heat is generated in the reactor core or reactor chamber 12 itself, no losses occur due to the introduction of a heat flow supplied from the outside.

[0053] 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 heat losses. The device 1 enables a particularly high power density and control dynamics, i.e., rapid power adaptability, with a small installation space requirement, thus enabling a wide scalability range and, in particular, small installation sizes.

[0054] Further technical contributions of the device 1 include high efficiency through reduced heat losses due to a small external surface, rapid heating behavior due to the thermal-mechanical material properties, in particular of SiSiC, and thus a short switch-on delay, which enables use in cyclically operated systems, for example. Furthermore, the device 1 is comparatively lightweight, in particular due to the use of SiSiC, which is particularly advantageous in non-stationary applications. The device 1 is highly corrosion-resistant against a variety of media, in particular against the influence of water vapor, ammonia, hydrogen, and nitrogen.

[0055] The device 1 enables a modular structure with which scaling for a wide performance spectrum can be realized.

[0056] 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.

[0057] Where applicable, all individual features shown in the embodiments may be combined and / or interchanged without departing from the scope of the invention. List of reference symbols

[0058] I Device for carrying out a chemical process

[0059] 10 reactor

[0060] II reactor casing

[0061] 12 reactor room

[0062] 13 Educt section

[0063] 14 Product section

[0064] 15 Catalyst

[0065] 16 Electrical connection

[0066] 17 Electrical connection

[0067] 18 Resistance heated section

[0068] 19 I insulator

[0069] 20 honeycomb bodies

[0070] 30 Thermal insulation

[0071] 100 reactor system

[0072] 101 Heat exchanger section

[0073] 102 Catalyst section

[0074] 110 Oven

[0075] III Electric heating

[0076] 120 pipe system

[0077] 121 Educt section

[0078] 122 Product section

[0079] E reactant

[0080] P Product

[0081] K catalyst

Claims

Claims 1. 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).

2. Device (1) according to claim 1, characterized in 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 in 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 in that a catalyst (15) is provided in the reactor chamber (12).

5. Device (1) according to claim 4, characterized in that the catalyst (15) is realized as beds of a catalytic material and / or a catalytically coated material and / or in that the Reactor chamber (12) is provided with a catalytic coating.

6. Device (1) according to one of the preceding claims, characterized in that 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 in that an electrical insulator (19) is installed on the side of the electrical connections (16, 17) opposite the resistance-heated section (18).

8. Device (1) according to one of the preceding claims, characterized in 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 in 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 in that the resistance-heated section (18) of the reactor chamber (12) comprises a honeycomb body (20), preferably extruded honeycomb body (20), contains an alternative geometric structure with a raised surface, preferably ribs, and / or a filling, preferably a ceramic fill.

11. Device (1) according to one of the preceding claims, characterized in 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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