DEVICE AND METHOD FOR HEATING A FLUID IN A PIPELINE

Abstract

An apparatus (112) for heating a fluid is proposed. The apparatus (112) comprises at least one electrically conductive pipeline (120) for receiving the fluid at least one electrically conductive coil (110) at least one AC voltage source (114), which is connected to the coil (110) and is designed for an AC voltage to be applied to the coil (110).

The coil (110) is designed for generating at least one electromagnetic field by applying the AC voltage. The pipeline (120) and the coil (110) are arranged in such a way that the electromagnetic field of the coil (110) induces in the pipeline (120) an electrical current, which warms up the pipeline (120) by Joulean heat, which is produced when the electrical current passes through conducting pipe material, for heating the fluid.

Claims

1.-15. (canceled)

16. An apparatus for heating a fluid, the apparatus being part of an installation, the installation being configured to carry out at least one process selected from the group consisting of: steam cracking; steam reforming; and alkane dehydrogenation, the apparatus comprising: at least one electrically conductive pipeline for receiving the fluid at least one electrically conductive coil, at least one AC voltage source, which is connected to the coil and is designed for an AC voltage to be applied to the coil, the coil being configured to generate at least one electromagnetic field by applying the AC voltage, the pipeline and the coil being arranged in such a way that the electromagnetic field of the coil induces in the pipeline an electrical current, which warms up the pipeline by Joulean heat, which is produced when the electrical current passes through conducting pipe material, for heating the fluid.

17. The apparatus according to claim 16, wherein the apparatus comprises a plurality of coils, the coils forming a substantially planar coil array.

18. The apparatus according to claim 17, wherein the coil array is adapted to a path followed by the pipeline.

19. The apparatus according to claim 17, wherein the apparatus comprises a plurality of AC voltage sources, each coil of the coil array being assigned an AC voltage source, the AC voltage sources being electrically controllable independently of one another.

20. The apparatus according to claim 16, wherein the apparatus comprises a plurality of pipelines, the pipelines being through-connected and thus forming a substantially planar pipe system for receiving the fluid.

21. The apparatus according to claim 16, wherein the apparatus comprises a plurality of coil arrays and/or pipe systems, the coil arrays and the pipe systems being arranged alternating in a horizontal direction in at least one stack.

22. The apparatus according to claim 16, wherein the apparatus comprises at least one heat insulator, configured to decouple the at least one coil from the temperature of the pipeline, the heat insulator comprising at least one element selected from the group consisting of: ceramic fiber mats, a ceramic foam, refractory bricks, refractory concrete.

23. The apparatus according to claim 16, wherein the coil comprises at least one conductor pipe, the apparatus being designed for conducting at least one coolant through the conductor pipe.

24. The apparatus according to claim 23, wherein the conductor pipe is of a pressure-resistant configuration.

25. The apparatus according to claim 16, wherein the pipeline is arranged in a gas space, the pipeline being arranged freely suspended in the gas space.

26. The apparatus according to claim 25, wherein a length and/or width and/or height of the gas space is configured in such a way as to allow changes in the position and length due to warming up.

27. The apparatus according to claim 25, wherein the apparatus is designed for the gas space to be flowed through by a chemically inert and oxygen-free inert gas.

28. The apparatus according to claim 25, wherein the apparatus comprises at least one leakage detection device, the leakage detection device being designed for monitoring a gas composition at an output of the gas space.

29. An installation comprising at least one apparatus according to claim 16, the installation being selected from the group consisting of: a steam cracker, a steam reformer, an apparatus for alkane dehydrogenation.

30. A method for heating a fluid by using an apparatus according to claim 16, the method comprising the following steps: providing at least one electrically conductive pipeline for receiving the fluid, receiving the fluid in the pipeline, providing at least one electrically conductive coil, providing at least one AC voltage source, the coil being connected to the AC voltage source, and applying an AC voltage to the coil, generating at least one electromagnetic field by applying the AC voltage to the coil, inducing an electrical current in the pipeline by the electromagnetic field of the coil, which warms up the pipeline by Joulean heat, which is produced when the electrical current passes through conducting pipe material, for heating the fluid.

31. The apparatus according to claim 19, wherein the AC voltage sources are configured to implement closed-loop control for adaptation of a level and/or frequency of the AC voltage.

Description

BRIEF DESCRIPTION OF THE FIGURES

[0073] Further details and features of the invention may be found in the following description of preferred examples, in particular in conjunction with the subclaims. The respective features may be implemented separately, or several of them may be implemented in combination with one another. The invention is not restricted to the examples. The examples are diagrammatically represented in the figures. References which are the same in the individual figures denote elements which are the same or have the same function, i.e. they correspond to one another in respect of their functions.

[0074] Specifically:

[0075] FIGS. 1A and 1B show diagrammatic representations of an example of a coil according to the invention and an example of a coil array according to the invention;

[0076] FIG. 2 shows a diagrammatic representation of an example of a pipe system according to the invention; and

[0077] FIGS. 3A and 3B show an exploded drawing of an example of an apparatus according to the invention and a perspective representation of a further example of the apparatus.

EXAMPLES

[0078] FIG. 1A shows a diagrammatic representation of an example of an electrically conductive coil 110 according to the invention of an apparatus 112 for heating at least one fluid. The fluid may for example be selected from the group consisting of: water, steam, a combustion air, a hydrocarbon mixture, a hydrocarbon to be cracked. For example, the fluid may be a hydrocarbon to be thermally cracked, in particular a mixture of hydrocarbons to be thermally cracked. For example, the fluid may be water or steam and additionally comprise a hydrocarbon to be thermally cracked, in particular a mixture of hydrocarbons to be thermally cracked. The fluid may for example be a preheated mixture of hydrocarbons to be thermally cracked and steam. Other fluids are also conceivable. For example, by the heating, the fluid may be warmed up to a prescribed or predetermined temperature value. The prescribed or predetermined temperature value may be a high-temperature value. For example, the fluid may be heated to a temperature in the range of 550° C. to 700° C. For example, the fluid may be a combustion air of a reformer furnace which is prewarmed or heated up, for example to a temperature in the range of 200° C. to 800° C., preferably of 400° C. to 700° C. However, other temperatures and temperature ranges are also conceivable.

[0079] The coil 110 may comprise at least one complete or partially closed conductor loop or winding. The coil 110 may generate a magnetic flux when an electrical voltage and/or an electrical current is applied. The electrically conductive coil may be an induction coil. The electrically conductive coil 110 may comprise at least one conducting material, for example copper or aluminum. The coil 110 may be constructed from tubular conductors that are flowed through by cooling medium. The winding form and number of windings of the coil may be selected in such a way that a maximum current intensity and/or maximum voltage and/or maximum frequency is achieved.

[0080] The apparatus 112 comprises at least one AC voltage source 114. The AC voltage source 114 is connected to the coil 110, in particular electrically connected. The apparatus 112 may comprise for this purpose at least one connecting element 116, for example a terminal and/or a feed line, which electrically connects the coil 110 and the AC voltage source 114. The AC voltage source 114 is designed for applying an AC voltage to the coil 110. The coil 110 is designed for generating at least one electromagnetic field in response to the application of the AC voltage.

[0081] The apparatus 112 may comprise a plurality of coils 110. The apparatus 112 may comprise M coils 110, M being a natural number greater than or equal to two. For example, the apparatus 112 may comprise at least two, three, four, five or more coils 110. The coils 110 may form a substantially planar coil array 118. An example of a coil array 118 is shown by FIG. 1B. The apparatus 112 may comprise a plurality of AC voltage sources 114. In the case of an apparatus 112 with a coil array 118, each coil 110 or a group of coils 110 may each be assigned an AC voltage source 114, which is connected to the respective coil 110 and/or group of coils 110, in particular electrically by way of at least one electrical connection. The AC voltage sources 114 may in each case be configured with a possibility of closed-loop control for adaptation of a level and/or frequency of the AC voltage. The AC voltage sources 114 may be electrically controllable independently of one another.

[0082] The apparatus 112 at least one electrically conductive pipeline 120 for receiving the fluid. The pipeline 120 may be a process pipe. The pipeline 120 may be designed as a reaction pipe of a reformer furnace. The pipeline 120 may comprise at least one pipeline segment. The geometry and/or surfaces and/or material of the pipeline 120 may be dependent on a fluid to be transported. The apparatus 112 may comprise a plurality of pipelines 120. The apparatus 112 may comprise L pipelines 112, L being a natural number greater than or equal to two. For example, the apparatus 112 may comprise at least two, three, four, five or more pipelines 120. The apparatus 112 may for example comprise up to several hundred pipelines 120. The pipelines 120 may be configured identically or differently. The pipelines 120 may comprise different numbers of legs or windings. The pipelines 120 may comprise different numbers of branches. The pipelines 120 may be configured as so-called single-pass or multi-pass pipes.

[0083] The pipelines 120 may comprise identical or different geometries and/or surfaces and/or materials. The pipelines 120 may be through-connected, and thus form a substantially planar pipe system 122 for receiving the fluid. An example of a pipe system 122 is shown by FIG. 2. The pipe system 122 may comprise incoming and outgoing pipelines 120. The pipe system 122 may comprise at least one inlet 124 for receiving the fluid. The pipe system 122 may comprise at least one outlet 126 for discharging the fluid. The pipelines 120 may be arranged and connected in such a way that the fluid flows through the pipelines 120 one after the other. The pipelines 120 may be interconnected parallel to one another in such a way that the fluid can flow through at least two pipelines 120 in parallel. The pipelines 120, in particular the pipelines 120 connected in parallel, may be designed in such a way as to transport different fluids in parallel. In particular, the pipelines 120 connected in parallel may comprise geometries and/or surfaces and/or materials that are different from one another for transporting different fluids. In particular for the transport of a fluid, a number or all of the pipelines 120 may be configured as parallel, so that the fluid can be divided among those pipelines 120 configured as parallel. Combinations of a series connection and a parallel connection are also conceivable.

[0084] The pipeline 120 may be arranged in a gas space 128. The pipeline 120 may be arranged freely suspended in the gas space 128. Thus, temperature-induced changes in length of the pipeline 120 can be made possible. Suspensions and procedures are known to a person skilled in the art. A length 130 and/or height 132 and/or width 134 of the gas space 128 may be configured in such a way as to allow changes in position and length due to warming up. For example, the pipe system 122 may define a plane. The length 130 of the gas space 128 may be an extent of the gas space 128 horizontally in relation to the path followed by the pipe system 122. The height 132 of the gas space 128 may be an extent in the plane of the pipe system 122 perpendicularly to the length 130 of the gas space 128. The width 134 of the gas space 128 may be an extent of the gas space 128 perpendicularly to the plane of the pipe system 122, see for example FIG. 3A. By contrast with directly fired radiant boilers, a minimum gas layer thickness is not required, so that the width 134 of the gas space 128 may enclose the pipeline 120 as closely as the changes in its position and length due to warming up allow, and/or that, in the case of a pipe rupture, the process gas can be safely removed in the plane of the planar pipe system 122. The apparatus 122 may be designed for the gas space 128 to be flowed through by a chemically inert and oxygen-free inert gas, for example nitrogen, in particular slowly. Thus, the pipeline 120 can be protected from scaling, and at the same time possible minor leakages can be safely removed before large amounts of combustible gases accumulate. The apparatus 112 may comprise at least one leakage detection device 136. The leakage detection device 136 may be designed for monitoring a gas composition at an output of the gas space 128.

[0085] FIGS. 3A and 3B show by way of example two examples of the apparatus 112, in an exploded drawing (FIG. 3A) and in a perspective representation (FIG. 3B). The coil 110 is designed for generating at least one electromagnetic field by applying the AC voltage. The pipeline 120 and the coil 110 are arranged in such a way that the electromagnetic field of the coil 110 induces an electrical current in the pipeline 120. In particular, a spacing of the pipeline 120 and the coil 110 may be such that the pipeline 120 is arranged in the electromagnetic field of the coil 110. The electrical current warms up the pipeline 120 by Joulean heat, which is produced when the electrical current passes through conducting pipe material, for heating the fluid.

[0086] The apparatus 112 may comprise a plurality of coil arrays 118 and/or pipe systems 122. The coil array 118 may be adapted to a path followed by the pipeline 122. In particular, the coil array 118 may be adapted to a path process heat requirement changing along the pipeline 120. For example, the coil array 118 may be configured in such a way that an energy input adapted to the process and the path followed by the pipelines 120 is possible.

[0087] The coil arrays 118 and the pipe systems 122 may be arranged alternating in a horizontal direction in at least one stack 138. In particular, a coil array 118 may be arranged in each case between two pipe systems 122. In the embodiment shown in FIG. 3A, the stack 138 may comprise a coil array 118 at one end, for example on a front side 140, the stack 138 comprising pipe systems 122 and further coil arrays 118 alternating in a horizontal direction of the stack 138. A pipe system 122 may be arranged on a rear side 142 of the stack 138. However, embodiments with a terminating coil array 118 are also conceivable. In the embodiment shown in FIG. 3B, the stack 138 may comprise a pipe system 122 on the front side 140 and the rear side 142, the stack 138 comprising coil arrays 118 and pipe systems 122 alternating in a horizontal direction of the stack 138. The apparatus 112 may comprise a different number or the same number of pipe systems 122 and coil arrays 118. For example, the apparatus 112 may comprise N pipe systems 122 and O coil arrays 118, N and O being natural numbers greater than or equal to two. For example, the apparatus 112 may comprise at least two, three, four, five or more coil arrays 118 and pipe systems 122. By such stacking of pipe systems 122 and coil arrays 118, tubular furnaces of the required capacity can be assembled. By using the respective front-side and rear-side electromagnetic fields of coil arrays 118 to the left and right of a pipe system 122 for heating the pipe system 122, field losses can be kept low. A mutual intensification of the fields of the coil arrays 118 to the left and right of a pipe system 122 may also be advantageous. The symmetrical field around the respective pipe system 122 may also be advantageous.

[0088] The stack 138 may comprise at least one compensation coil array. The compensation coil array may be designed for keeping a front-side and/or rear-side electromagnetic field of the stack 138 as small as possible. The stack may be closed off at the free ends by a combination of a pipeline or pipe system used for low temperatures, for example preheaters or reactant evaporators, and a compensation coil array in such a way that a residual external electromagnetic field is as small as possible. For example, the last coil array 118 of the stack 138 in each case may be configured as a compensation coil array.

[0089] The apparatus 112 may comprise at least one heat insulator 144, see for example FIG. 1B, which is designed for decoupling the coil 110, in particular the coil array 118, from the temperature of the pipeline 120, in particular the pipe system 122. For example, the substantially planar coil array 118 may be embedded in an electrically non-conductive and non-magnetic heat insulating compound. The heat insulator 144 may comprise at least one element selected from the group consisting of: ceramic fiber mats, a ceramic foam, refractory bricks, refractory concrete.

[0090] The coil 110 may comprise at least one conductor pipe 146, see for example FIGS. 1A and 1B. The apparatus 112 may be designed for conducting at least one coolant through the conductor pipe 146. A power loss of the coil and a heat input through the heat insulator 144 from a process space, in which the pipelines 120 are arranged, into the coils 110 can be removed by direct cooling of the coils 110. For example, the coil 110 may be configured from copper or aluminum pipes through which the coolant is conducted. The conductor pipe 146 may be of a pressure-resistant configuration. It may thus be possible to apply boiler feed water directly to the conductor pipe 146 and to generate steam either in the conductor pipe 146 directly or in an external steam drum after throttling the pressurized water from the conductor pipe 146. The steam may be used as process steam or machine steam.

LIST OF REFERENCE SIGNS

[0091] 110 Coil [0092] 112 Apparatus [0093] 114 AC voltage source [0094] 116 Connecting element [0095] 118 Coil array [0096] 120 Pipeline [0097] 122 Pipe system [0098] 124 Inlet [0099] 126 Outlet [0100] 128 Gas space [0101] 130 Length [0102] 132 Height [0103] 134 Width [0104] 136 Leakage detection device [0105] 138 Stack [0106] 140 Front side [0107] 142 Rear side [0108] 144 Heat insulator [0109] 146 Conductor pipe