Discontinuously operated desublimator with at least three guide vanes

Abstract

Discontinuously operated desublimator (1) for removing at least one gas component to be desublimated from a gas mixture flow comprising a housing wall (7) as an outer boundary, an inlet nozzle (10) on the housing wall (7) for supplying the gas mixture flow into the desublimator (1), an outlet (6) on the housing wall (7) for discharging the treated gas mixture flow from the desublimator (1), a desublimation zone (4) with temperature-controlled flow channel walls, wherein the flow channel walls are temperature-controlled such that during a loading process the at least one gas component to be desublimated desublimates at the flow channel walls, and that during a subsequent melting process the at least one gas component desublimated in the loading process melts at the flow channel walls, a gas inlet distribution chamber (3) located between the inlet (2) and the desublimation zone (4), and a gas outlet space (5) located between the outlet (6) and the desublimation zone (4), characterized by the fact that at least a first guide plate (8a), a second guide plate (8b) and a third guide plate (8c) are arranged in the gas inlet distribution chamber (3) for the uniform distribution of the gas mixture flow through the flow channels that result from the flow channel walls of the desublimation zone (4), and wherein at least three guide plates (8a, 8b, 8c) each have a distance (H LB, a-b , H LB , b-c ) to their adjacent guide plate or to their adjacent guide plates in the range of 0.01 to 0.9 * D, preferably in the range of 0.10 to 0.50 * D, wherein D corresponds to the equivalent diameter of a circle with the same area as the inlet surface (9).

Description

[0001] The invention relates to a batch-operated desublimator for removing at least one gas component to be desublimated from a gas mixture flow. The desublimator comprises a housing wall, an inlet on the housing wall for supplying the gas mixture flow, an outlet on the housing wall for discharging the treated gas mixture flow, and a desublimation zone with temperature-controlled flow channel walls. The flow channel walls are temperature-controlled such that, during a loading process, the at least one gas component to be desublimated desublyzes at the flow channel walls, and during a subsequent melting process, the at least one gas component desublimated during the loading process melts at the flow channel walls. The desublimator also includes a gas inlet distribution chamber located between the inlet and the desublimation zone, and a gas outlet chamber located between the outlet and the desublimation zone.

[0002] Known batch-operated desublimators have internal flow channel walls, which can be in the form of bundles of finned tubes. Finned tubes are characterized by the fact that their tubes are surrounded by fins, which can be heated or cooled by a fluid flowing through the tubes. During the loading process, a gas component to be desublimated, contained in a gas or gas-vapor mixture, is separated by desublimation at the cooled fins. In a subsequent melting process, the gas component desublimated at the now heated walls of the finned tubes is melted and discharged from the desublimator. Instead of finned tubes, other flow channel wall designs, such as lamellae or honeycomb structures, can also be arranged in the desublimator.When using fins, the cooling or heating medium is usually guided through fluid lines, which are generally located on the outside of the housing walls, so that the heat transfer essentially takes place between the externally located fluid lines and the housing wall and between the housing wall and the fins.

[0003] In such desublimators as described above, the gas mixture flow exhibits poor uniformity with respect to the flow through the flow channels during the loading process, resulting in uneven desublimation of the gas component to be desublimated at the flow channel walls. Consequently, the pressure drop between the inlet and outlet of the desublimator increases more rapidly during the loading process, and the desublimator must therefore be regenerated more frequently, even though its maximum loading capacity has not yet been reached.

[0004] The desublimator is typically regenerated through the melting process and an optional subsequent cooling process.

[0005] German patent DE 3407104 A1 discloses batch-operated desublimators for separating products from gas mixtures. These devices feature internal fins as flow channel walls, which are attached to the housing side walls. A cooling or heating medium is conveyed through fluid lines located only on the outer housing side walls. Heat transfer occurs when the fins are heated, from the fluid lines to the housing side walls and from the housing side walls to the fins. Conversely, when the fins are cooled, heat transfer occurs from the fins to the housing side walls and from the housing side walls to the fluid lines. These desublimators are used, for example, in the production of phthalic anhydride (PSA). However, this results in significant parasitic heat losses to the environment, as the desublimator is heated or cooled only externally. Larger desublimators with an internal volume of, for example, more than 1 m³ are also affected. 3However, during operation of the desublimator, the heat transfer between the housing sidewalls and the fins located further away from the housing sidewalls is generally too low, resulting in a temperature gradient within the fins during the loading process. This leads to different desublimation rates. Consequently, the pressure drop increases more rapidly during the loading process, and the desublimator must be regenerated more frequently, even though its maximum loading capacity has not yet been reached.

[0006] DE102015101398 A1 discloses a discontinuously operated desublimator in a cylindrical design for removing a gas component to be desublimated from a gas flow. The desublimator comprises a housing containing an inner fluid channel and fins as flow channel walls, which are arranged on an inner side of the housing wall and directed inwards. The fins can also be cooled by a coolant flowing through the inner fluid channel or heated by a heating medium flowing through the inner fluid channel. However, if such desublimators have an internal volume of, for example, more than 1 m³ 3If the fins exhibit this characteristic, the heat transfer from the inner fluid line to the areas of the fins further away from the fluid line is generally too low, resulting in a temperature gradient within the fins. This gradient leads to varying desublimation rates during the charging process. With longer designs of such desublimators, the disadvantage arises that desublimation occurs particularly at the fin locations near the gas mixture inlet. This can cause the fins in the inlet area to clog rapidly, even if desublimation has not yet occurred on all fin surface areas. Due to the disadvantages described above, the pressure drop increases more rapidly during the charging process, and the desublimator must therefore be regenerated more frequently, even though its maximum charging capacity has not yet been reached.

[0007] The challenge, therefore, was to provide a desublimator that achieves the most uniform possible gas mixture flow through the flow channels of the desublimation zone during its loading process. A further challenge was to ensure that the pressure drop between the desublimator's inlet and outlet increased as slowly as possible during the loading process, thus allowing for longer regeneration intervals. Finally, the task was to provide a desublimator with a greater loading capacity for desublimating gas components at a given maximum pressure drop between the inlet and outlet, or at a given maximum loading time.

[0008] These problems are solved according to the present invention by a discontinuously operated desublimator according to claim 1. Advantageous embodiments of the desublimator are given in claims 2 to 15.

[0009] The discontinuously operated desublimator according to the invention for removing at least one gas component to be desublimated from a gas mixture flow comprises a housing wall, an inlet on the housing wall for supplying the gas mixture flow into the desublimator, an outlet on the housing wall for discharging the treated gas mixture flow from the desublimator, a desublimation zone with temperature-controlled flow channel walls, wherein the flow channel walls are temperature-controlled such that during a loading process the at least one gas component to be desublimated desublimates on the flow channel walls, and that during a subsequent melting process the at least one gas component desublimated in the loading process melts on the flow channel walls, a gas inlet distribution chamber located between the inlet and the desublimation zone, and a gas outlet chamber located between the outlet and the desublimation zone.

[0010] According to the invention, at least a first guide plate, a second guide plate and a third guide plate are arranged in the gas inlet distribution chamber for the uniform distribution of the gas mixture flow through the flow channels that result from the flow channel walls of the desublimation zone. and wherein at least three guide plates each have a distance to their adjacent guide plate or to their adjacent guide plates in the range of 0.01 to 0.9 * D, preferably in the range of 0.10 to 0.50 * D, where D corresponds to the equivalent diameter of a circle with the same area as the inlet surface.

[0011] The at least three guide vanes in the gas inlet distribution chamber distribute the incoming gas mixture flow more evenly through the individual flow channels of the desublimation zone during the loading process, resulting in more uniform desublimation at the flow channel walls. This more uniform flow through the channels and the more uniform desublimation at the flow channel walls prevent excessively high gas mixture flow velocities, which can sometimes be well over twice the average velocity of the gas mixture flow through the desublimation zone. Furthermore, the interaction between the flow channel walls and the gas mixture flow is enhanced. Uneven flow through the flow channels quickly leads to blockages or significant constrictions in the channels through which the gas flows at higher velocities.Due to blockages or constrictions, the remaining open flow channels must be traversed at increased velocities of the gas mixture because the mass flow rate of the gas mixture through the desublimator is kept constant. With increased blockages, the velocity of the gas mixture through the remaining open flow channels increases correspondingly more significantly, which means that complete separation of the gas component to be desublimated in the desublimator can no longer be guaranteed. This is because the increased velocity of the gas mixture results in an insufficient residence time in the affected flow channel to completely desublimate the gas component at the flow channel wall.

[0012] The desublimation of at least one gas component to be desublimated coats the surfaces of the flow channel walls, causing a corresponding increase in the pressure drop across the individual flow channels during the loading process. Due to the more uniform flow through the flow channels and the more uniform desublimation on the flow channel walls, the pressure drop across the individual flow channels increases more slowly. Thus, the pressure drop between the inlet and outlet of the desublimator according to the invention also increases more slowly during the loading process, and the desublimator can consequently be regenerated at longer intervals.Furthermore, compared to a desublimator without at least three guide vanes, the desublimator according to the invention can desublimate more of the at least one gas component to be desublimated at its flow channel walls at the same pressure drop between the inlet and outlet of the desublimator, thereby achieving a greater loading capacity for the same pressure drop. Moreover, regardless of the pressure drop, more of the gas component to be desublimated can be separated in the desublimator during the same loading time, without a significant or disruptive proportion of the gas component to be desublimated being present in the gas mixture flow at the outlet of the desublimator.

[0013] In this document, the term "gas mixture flow" generally refers to a flowing gas mixture. The gas mixture can also be a gas-vapor mixture. In principle, the gas mixture may contain liquid droplets or solid particles, provided that the desublimator is not damaged or clogged.

[0014] In this document, the term "a gas component to be desublimated" generally refers to a gas component that predominantly desublimates at the flow channel walls within a desublimation zone, where the flow channel walls have a lower temperature than the desublimation temperature during a loading process. In thermodynamics, desublimation is the process of the direct transition of a substance from the gaseous to the solid state. The desublimation temperature indicates the maximum temperature at a given pressure below which a gas component transitions to the solid state.

[0015] In this document, the term "fluid line" refers to a flowable conduit through which a cooling or heating medium can flow. The fluid line can be located on the outside of the housing wall and / or inside the desublimator. If one or more fluid lines are located externally, heat transfer occurs between the fluid line(s) and the housing wall, thus allowing the temperature control of the gas mixture flow in contact with the inside of the housing wall. Additionally, the flow channel walls can also be temperature controlled if they are thermally coupled to the inside of the housing wall. If one or more fluid lines are located inside the desublimator, heat transfer generally occurs predominantly between the fluid line(s) and the flow channel walls, thus allowing the temperature control of the flow channel walls.

[0016] In this document, the term "housing wall" generally refers to the outer boundary of the desublimator. The housing wall is also typically referred to as the casing in the literature. The walls of the housing wall exhibit sufficient technical tightness. Typically, the outer surface of the housing wall is at least partially heated by an external heating element. This external heating element is usually provided by one or more fluid lines, which are typically mounted directly to the outer surface of the housing wall. During operation of the desublimator, a cooling or heating medium is usually circulated through the fluid line(s) to appropriately temperature-control the gas mixture flow and / or the flow channel walls. One or more inlet and outlet surfaces are provided by corresponding recesses in the housing wall.

[0017] In this document, the term "desublimation zone with temperature-controlled flow channel walls" generally refers to an area in which, during a loading process, at least one gas component to be desublimated desublyzes at the flow channel walls, and the remaining gas mixture flow, also referred to as the treated gas mixture flow, flows out of the desublimation zone and thus reaches the gas outlet chamber. In a melting process following the loading process, the flow channel walls of the desublimation zone are heated to melt the desublimated gas component(s) at the flow channel walls and discharge them from the desublimator.

[0018] The temperature-controlled flow channel walls of the desublimation zone can be formed, for example, by the outer walls of finned tubes, finned tube bundles, tube bundles, lamellar bodies, honeycomb bodies, pipe rods, pipe rod bundles, or plate bodies. Lamellar, plate, or honeycomb bodies are defined as internal components containing lamellae, plates, or honeycombs, respectively. In the case of a lamellar body, the cavities between the individual lamellae form the flow channels. Accordingly, the flow channel walls are defined by the lamella surfaces. In the case of finned tubes, the adjacent lamellae form a cavity as a supporting flow channel through which a fluid, such as a gas mixture, can flow.Typically, bundles of finned tubes are arranged in the desublimation zone, whereby, for example, adjacent finned tubes can form further flow channels or individual finned tubes in combination with correspondingly adjacent finned tubes can form continuous flow channels.

[0019] The flow channels can all have the same diameter by spacing the fins of the finned tube(s) equidistantly. Preferably, however, the flow channels have different diameters by spacing the fins of the finned tube(s) differently. For more uniform flow through the channels, it can be advantageous if the channel diameter at the inlet of each flow channel is larger than at the outlet. Furthermore, the at least one gas component to be desublimated desublys more uniformly along the length of the flow channel walls. The finned tube(s) can be circular, oval, or rectangular.

[0020] Furthermore, the inlet area of ​​the desublimation zone is defined by the fictitious interface between the gas inlet distribution chamber and the desublimation zone, whereby the surfaces of the respective flow channel walls located in the interface are also assigned to the inlet area of ​​the desublimation zone for simplification.

[0021] The outlet surface of the desublimation zone is defined by the fictitious interface between the gas outlet distribution chamber and the desublimation zone, whereby the surfaces of the respective flow channel walls located in the interface are also assigned to the outlet surface of the desublimation zone for simplification.

[0022] The ratio between the inlet area of ​​the desublimation zone and the distance between the inlet and outlet areas of the desublimation zone should preferably be greater than 5 [m²]. 2 / m], where the inlet area in square meters [m²] is used to calculate the ratio. 2] and the distance between the inlet and outlet surfaces of the desublimation zone is to be measured in meters [m]. Maintaining the preferred range for the ratio prevents significantly excessive desublimation at the flow channel walls in the region of the desublimation zone's inlet area. Increased desublimation at a flow channel wall significantly reduces the minimum free gas passage area of ​​the channel within a very short loading time. This would cause the pressure drop across the flow channel to increase rapidly at the beginning of the loading process, ultimately leading to blockage of the flow channel after a very short loading time, even if desublimation at the flow channel wall were to occur primarily in the region of the desublimation zone's inlet area.The larger the available inlet area, the less likely increased desublimation at the flow channel walls in the area of ​​the desublimation zone inlet can lead to a significantly greater pressure loss or even a blockage. To ensure a desublimator is designed to be cost-effective and space-saving, the ratio between the inlet area of ​​the desublimation zone and the distance between the inlet and outlet areas of the desublimation zone should preferably be less than 100 m. 2 / m], where the inlet area in square meters [m²] is used to calculate the ratio. 2 ] and the distance between the inlet and outlet surfaces of the desublimation zone is to be measured in meters [m]. Overall, it follows that the ratio between the inlet area of ​​the desublimation zone and the distance between the inlet and outlet surfaces of the desublimation zone is preferably in the range of 5 to 100 m. 2 / m is located.

[0023] To regulate the temperature of the flow channel walls in the desublimation zone, one or more flowable fluid lines can be arranged within the desublimation zone. These lines can be filled with a heating or cooling fluid, thus tempering the walls of the fluid line(s). The heat transfer between the flow channel walls and the flowable fluid line(s) results in the corresponding temperature regulation of the flow channel walls. Additionally or alternatively, temperature regulation can be achieved by an external flowable fluid line or by several external flowable fluid lines arranged on the outside of the housing wall.In this process, the walls of the desublimation zone are tempered by heat transfer between the flow channel walls and the outer fluid line(s), with heat transfer also occurring through the intervening housing wall. If a coolant flows through the inner or outer fluid line(s) during the loading process, the walls of the flow channels are cooled by heat conduction between the flow channel walls and the fluid line(s), allowing at least one gas component to desublimate to desublimate on the walls of the flow channels.If a heating medium flows through the inner or outer fluid line(s) during the melting process, the walls of the flow channels are heated due to heat conduction between the flow channel walls and the fluid line(s), allowing the gas component(s) desublimated on the walls of the flow channels to melt. For example, a different or the same heat transfer oil, such as Diphyl DT, can be used as the heating or cooling medium.

[0024] In this document, the term "desublimated on the flow channel walls" generally refers to a deposition process in which at least one gas component to be desublimated, contained in a gas mixture flow, is cooled to such an extent that it desublimates and deposits on the flow channel walls. The desublimated gas component(s) then adhere to the flow channel walls in a solid state. Depending on the prevailing thermodynamic conditions, the term "desublimated" can also be understood in this document to mean that, within the desublimation zone, a phase change first occurs in at least a portion of the gas mixture flow from a gaseous to a liquid state, followed by a phase change from the liquid to the solid state. The flow channel walls of the desublimation zone are accordingly at least partially wetted by the liquid resulting from the phase change.Due to the cooled flow channel walls, the phase change from liquid to solid state occurs at the flow channel walls within a very short time. In summary, the gas component to be desublimated also desublimates at the flow channel walls of the desublimation zone and adheres to the flow channel walls in the solid state.

[0025] In this document, the term "gas inlet distribution chamber" generally refers to a space within the desublimator, bounded by the desublimator housing wall, the desublimator inlet area, and the desublimation zone. During a loading process, a gas mixture flows through the gas inlet distribution chamber, entering through an inlet on the desublimator. The desublimation zone, with temperature-controlled flow channel walls, adjoins the gas inlet distribution chamber. The gas mixture typically exits the gas inlet distribution chamber only through this desublimation zone.

[0026] In this document, the term "gas outlet chamber" generally refers to a chamber into which a gas mixture flow can be supplied from its adjacent desublimation zone. This chamber typically also has an outlet through which the treated gas mixture flow can escape from the desublimator.

[0027] Typically, there is also a second outlet port with a drain valve, which may be, for example, a sealing cap. During a melting process, the drain valve is open, allowing the generated molten metal to flow out of the desublimator. During a loading process, the drain valve is closed, preventing any fluid from flowing out of the outlet port. This second outlet port is typically located at the lowest point of the gas outlet chamber, allowing the molten metal to flow to it due to gravity.

[0028] In this document, the term "discontinuously operated desublimator" generally refers to a desublimator that is typically operated discontinuously with two or three different process cycles. The first process cycle is a loading process in which at least one gas component to be desublimated desublyzes on the flow channel walls of the desublimation zone. During the loading process, the flow channel walls are cooled. The second process cycle is a melting process in which the desublimated gas component(s) melts due to heating of the flow channel walls of the desublimation zone and is / are discharged from the desublimator.

[0029] The third process cycle represents an optional recooling process in which the flow channel walls of the desublimation zone are cooled after the desublimated gas component(s) have been removed from the desublimator. Alternatively, the cooling of the flow channel walls can take place at the beginning of the loading process.

[0030] In this document, the term "loading process" generally refers to a process cycle during the operation of a desublimator, in which the desublimator is operated until a predetermined loading level or loading time is reached by one or more desublimated gas components on the flow channel walls of the desublimation zone. Here, the loading level is understood as the deposited mass of one or more desublimated gas components on the flow channel walls.

[0031] In this document, the term "loading capacity" generally refers to the total mass of desublimated gas component(s) that desublimates on the flow channel walls during a loading process before the pressure drop between the inlet and outlet of the desublimator exceeds a predetermined value and / or until a predetermined loading time is reached.

[0032] In this document, the term "melting process" generally refers to a process cycle during the operation of a desublimator, in which the desublimator has reached its loading capacity and subsequently the desublimated gas component(s) melts by heating the flow channel walls and can flow out of the desublimator, for example, through a drain nozzle located at the bottom of the desublimator. Typically, the gas mixture flow into the desublimator is stopped during the melting process. The melting process is also commonly referred to as the regeneration process.

[0033] In this document, the term "recooling process" generally refers to an optional process cycle during the operation of a desublimator, in which the flow channel walls of the desublimation zone are cooled after the desublimated gas component(s) have been removed from the desublimator. Typically, the recooling process, in conjunction with the upstream melting process, is also referred to as the regeneration process.

[0034] In this document, the term "guide plate" generally refers to a component that, during the loading process, ensures that a gas mixture flowing in from the inlet is distributed as evenly as possible through the flow channels of the desublimation zone. The at least three guide plates can also be heated, for example, by mounting them on the housing side walls of a desublimator in such a way that a sufficient heat flow can travel from the housing side walls to the respective guide plates. Alternatively, a heating element for at least one guide plate, such as an electric heater in contact with the corresponding guide plate, is conceivable.

[0035] In this document, the term "guide plate porosity" defines the ratio between the free area and the total surface area of ​​the guide plate. The "guide plate porosity" thus corresponds to the "relative free area of ​​the guide plate".

[0036] In this document, the term "flow surface" is generally understood to mean a surface that is subject to a fluid flow and thus experiences a flow pressure in the direction of the surface.

[0037] In a preferred embodiment of the desublimator according to the invention, the at least three guide vanes each have a distance to their adjacent guide vane(s) in the range of 0.01 to 0.9 * D, preferably in the range of 0.10 to 0.50 * D, where D corresponds to the equivalent diameter of a circle with the same area as the inlet area. This achieves a flow through the flow channels of the desublimation zone that is as uniform as possible, because the gas mixture flow from the inlet is better distributed into the gas inlet distribution chamber.

[0038] In a preferred embodiment of the desublimator according to the invention, the first guide plate has a distance from the wall of the inlet nozzle in the range of 0 to 1 * D, preferably in the range of 0 to 0.3 * D, and the third guide plate has a distance from the wall of the inlet nozzle in the range of 0 to 1 * D, preferably in the range of 0 to 0.3 * D, where D corresponds to the equivalent diameter of a circle with the same area as the inlet area. This has the advantage that a flow through the flow channels of the desublimation zone is achieved as uniformly as possible, because the gas mixture flow from the inlet is better distributed into the gas inlet distribution chamber.

[0039] In a preferred embodiment of the desublimator according to the invention, the at least three guide vanes each extend with their transverse axis substantially to at least one of the two opposing housing side walls, preferably to both opposing housing side walls of the desublimator. This achieves a flow distribution that is as uniform as possible in the gas inlet distribution chamber, because the gas mixture flow in the gas inlet distribution chamber is at least partially separated in the direction of the transverse axis of the desublimator. Consequently, a flow distribution that is as uniform as possible is achieved through the flow channels of the desublimation zone.

[0040] In a preferred embodiment of the desublimator according to the invention, the at least three guide vanes each have a length along their transverse axis in the range of 0.1 to 5 * D, preferably in the range of 0.5 to 5 * D, and particularly preferably in the range of 1.0 to 3 * D, where D corresponds to the equivalent diameter of a circle with the same area as the inlet area. This achieves a flow distribution that is as uniform as possible in the gas inlet distribution chamber, because the gas mixture flow in the gas inlet distribution chamber is at least partially separated in the direction of the transverse axis of the desublimator. Consequently, a flow distribution that is as uniform as possible is achieved through the flow channels of the desublimation zone.

[0041] In a preferred embodiment of the desublimator according to the invention, the at least three guide vanes each have a length along their longitudinal axis in the range of 0.1 to 9 * D, preferably in the range of 0.1 to 3 * D, and particularly preferably in the range of 0.2 to 1.25 * D, where L corresponds to the length of the longitudinal axis of the desublimator. This has the advantage of achieving a flow that is as uniform as possible in the gas inlet distribution chamber, because the gas mixture flow in the gas inlet distribution chamber is at least partially separated in the direction of the longitudinal axis of the desublimator. Consequently, a flow that is as uniform as possible is achieved through the flow channels of the desublimation zone.

[0042] In a preferred embodiment of the desublimator according to the invention, the at least three guide vanes each have an internal angle in the range of 0 to 90°, preferably in the range of 5 to 85°, wherein the respective internal angle is formed between the longitudinal axis of the respective guide vane and the longitudinal axis of the flow channel walls. This orientation of the guide vanes ensures a flow distribution that is as uniform as possible in the gas inlet distribution chamber. Consequently, a flow distribution that is as uniform as possible is achieved through the flow channels of the desublimation zone.

[0043] In a preferred embodiment of the desublimator according to the invention, the at least three guide vanes each have an internal angle designed such that the extension of the respective guide vanes in the direction of their longitudinal axis intersects the inlet surface of the desublimation zone in such a way that the inlet surface of the desublimation zone is divided into substantially equal areas. This orientation of the guide vanes ensures that the gas mixture flow is distributed as evenly as possible across the inlet surface of the desublimation zone. Consequently, a flow through the flow channels of the desublimation zone is achieved that is as uniform as possible.

[0044] In a preferred embodiment of the desublimator according to the invention, the inner angles of the guide vanes can be adjusted outside and / or inside the desublimator. This offers the advantage that the guide vanes can be optimally adjusted from the outside and / or inside, depending on the operating mode of the desublimator, in order to achieve the most uniform flow possible through the flow channels of the desublimation zone.

[0045] In a preferred embodiment of the desublimator according to the invention, the at least three guide vanes are each arranged such that the inlet surface intersects the respective guide vanes or the extensions of the respective guide vanes along their longitudinal axis, dividing the inlet surface into substantially equal areas. In the case of more than three guide vanes, the additional guide vanes can also be fixed at the edge of the inlet surface or fixed outside the inlet surface in such a way that their extensions along their longitudinal axis do not intersect the inlet surface. This orientation of the guide vanes ensures that the gas mixture flow is distributed as evenly as possible across the inlet surface of the desublimation zone. Consequently, a flow through the flow channels of the desublimation zone is achieved with the highest possible uniformity.

[0046] In a preferred embodiment of the desublimator according to the invention, the at least three guide plates each have a straight, corrugated, folded or bent, flat profile, preferably a lamellar profile. This has the advantage that the gas mixture flow into the gas inlet distribution chamber is distributed as efficiently and effectively as possible, so that a flow through the flow channels of the desublimation zone is achieved as uniformly as possible.

[0047] In a preferred embodiment of the desublimator according to the invention, at least one guide plate is oriented towards the housing side wall such that the flow channels of the desublimation zone in the region of the inlet surface, preferably those flow channels that have a distance from the inlet surface in the range of 0 to 30% of the length of the desublimator, flow more evenly through the flow channels near the housing side wall. This offers an advantage for desublimators with a larger width-to-length ratio. This is because the gas mixture flow is also better distributed towards the housing side walls by such oriented guide plates. Consequently, a flow through the flow channels of the desublimation zone is achieved that is as evenly distributed as possible.

[0048] In a preferred embodiment of the desublimator according to the invention, at least one of the at least three guide plates has a porosity in the range of 0 to 80%, preferably in the range of 0 to 50%. In certain cases, a guide plate could deflect the gas mixture flow too much, causing a few flow channels to be excessively saturated. The porosity of the guide plate prevents or sufficiently reduces this effect.

[0049] In a preferred embodiment of the desublimator according to the invention, the inlet surface has a distance to the housing wall in the range of 0 to 10.0 * D, preferably in the range of 0.2 to 0.6 * D, where D corresponds to the equivalent diameter of a circle with the same area as the inlet surface. This ensures that the inlet surface is optimally positioned in the gas inlet distribution chamber in order to achieve the most uniform flow possible through the flow channels of the desublimation zone.

[0050] In a preferred embodiment of the desublimator according to the invention, the desublimation zone has a distance from the inlet surface in the range of 0.01 to 3 * D, preferably in the range of 0.1 to 0.5 * D, where D corresponds to the equivalent diameter of a circle with the same area as the inlet surface. This means that the gas mixture flow at the inlet has a less significant influence on the flow through the desublimation zone, resulting in a flow that is as uniformly distributed as possible through the flow channels of the desublimation zone.

[0051] In a preferred embodiment of the desublimator according to the invention, the at least three guide vanes each have a distance from the inlet surface in the range of 0 to 300 mm, the respective distance being measured along the longitudinal axis of the desublimator. This ensures that the guide vanes are optimally positioned relative to the inlet surface, thereby efficiently and effectively redirecting the gas mixture flow to achieve the most uniform flow possible through the flow channels of the desublimation zone.

[0052] In a preferred embodiment of the desublimator according to the invention, the desublimator has a horizontal longitudinal axis oriented perpendicular to the longitudinal axis of the flow channels of the desublimation zone, and the gas inlet distribution chamber is arranged above the desublimation zone. This has the advantage that, during the loading process, the cooling of the gas mixture flow in the flow channels of the desublimation zone causes the gas mixture to flow more strongly towards the gas outlet chamber due to the resulting convection effect.

[0053] In a preferred embodiment of the desublimator according to the invention, the flow channel walls are formed by the outer walls of a tube bundle, a finned tube, a finned tube bundle, a lamellar body, a honeycomb body, and / or a plate body. This offers the advantage that, during the loading process, the at least one gas component to be desublimated efficiently desublimates at the flow channel walls of the desublimation zone, and that the pressure drop across the desublimation zone is kept to a minimum during the loading process.

[0054] Another object of the invention is a method for operating a desublimator according to the invention.

[0055] In the inventive method for operating a desublimator according to the invention, during the loading process of the desublimator, the gas mixture flow containing at least one gas component to be desublimated flows at a mass flow rate of at least 0.01 kg / s, at a temperature in the range of above the desublimation temperature at the given pressure up to 300 °C above the desublimation temperature of the at least one gas component to be desublimated at the given pressure, and at an absolute pressure in the range of 0.1 to 10.00 bar, preferably in the range of 0.5 to 1.5 bar, particularly preferably in the range of 1.05 to 1.10 bar. The flow channel walls of the desublimation zone are cooled to a temperature in the range of 150 °C below the desublimation temperature at the given pressure up to 1 °C below the desublimation temperature at the given pressure.The at least one gas component to be desublimated in the gas mixture flow desublimates at least partially within the desublimator. Preferably, the at least one gas component to be desublimated desublimates in the range of 10 to 100 wt.%, based on the at least one gas component to be desublimated flowing into the inlet of the gas mixture flow. Particularly preferably, the at least one gas component to be desublimated desublimates in the range of 50 to 100 wt.%, based on the at least one gas component to be desublimated flowing into the inlet of the gas mixture flow. In the case that several gas components to be desublimated are present in the gas mixture flow, the ranges specified above refer to the respective gas component to be desublimated.

[0056] This offers the advantage that, during the loading process, at least one gas component to be desublimated efficiently desublimates at the flow channel walls of the desublimation zone, and that the pressure drop across the desublimation zone is minimized during the loading process. Furthermore, the gas mixture flows more uniformly through the flow channels of the desublimation zone.

[0057] In a preferred embodiment of the inventive method for operating a desublimator according to the invention, the pressure loss between the inlet and outlet of the desublimator during the loading process is a maximum of 80 mbar, preferably a maximum of 40 mbar, and particularly preferably a maximum of 20 mbar.

[0058] This offers the advantage that the pressure drop does not become too high during maximum load operation of the charging process. If the pressure drop were to become too high, the mass flow rate of the gas mixture at the inlet could decrease. In this case, a compressor or fan could be used to achieve the desired mass flow rate of the gas mixture at the inlet. However, this carries the risk that the pump will become clogged with at least one of the gas components to be desublimated during operation and thus have to be switched off.

[0059] In a preferred embodiment of the inventive method for operating a desublimator according to the invention, after reaching a predetermined loading of the at least one desublimated gas component on the flow channel walls of the desublimator or after reaching a predetermined loading time, a melting process takes place which comprises the following steps: • Shutting off the supply of the gas mixture flow to the desublimator, • Heating the flow channel walls of the desublimation zone to a temperature in the range from the desublimation temperature at the given pressure to 300 °C above the desublimation temperature at the given pressure of at least one gas component to be desublimated, • Melting of at least one desublimated gas component in the desublimator to obtain a melt, and • Removal of the melt from the desublimator, wherein the removal preferably takes place through an outlet nozzle on the housing wall of the gas outlet chamber, wherein the outlet nozzle is preferably located at the lowest point of the desublimator.

[0060] This offers the advantage that the melting process is efficient. For example, it is not necessary to scrape the desublimated gas component(s) from the flow channel walls of the desublimation zone.

[0061] In a preferred embodiment of the inventive method for operating a desublimator according to the invention, a cooling process takes place after the melt has been removed from the desublimator, in which the flow channel walls of the desublimation zone are cooled to a temperature in the range of 150 °C below the desublimation temperature at the given pressure up to 1 °C below the desublimation temperature at the given pressure.

[0062] This offers the advantage that the flow channels of the desublimation zone already reach the required temperature for desublimation before the loading process. Thus, at least one gas component to be desublimated is efficiently separated from the gas mixture flow right at the beginning of the loading process.

[0063] In a preferred embodiment of the inventive method for operating a desublimator according to the invention, the at least one gas component to be desublimated contains predominantly phthalic anhydride, preferably only phthalic anhydride, in its mass fraction.

[0064] In a preferred embodiment of the inventive method for operating a desublimator according to the invention, the concentration of the at least one gas component to be desublimated in the gas mixture flow at the inlet is in the range of 0.001 to 50 wt.%, preferably in the range of 0.1 to 10 wt.%.

[0065] This has the advantage that at least one gas component to be desublimated is efficiently separated from the gas mixture flow.

[0066] The invention is explained in more detail below with reference to the drawings. The drawings are to be understood as schematic representations. They do not represent any limitation of the invention, for example with regard to specific dimensions or embodiments. They show: Fig. 1: A drawing of a first exemplary embodiment of a desublimator according to the invention in longitudinal section. Fig. 2: A drawing of the first exemplary embodiment of a desublimator according to the invention. Fig. 1 in cross-section. Fig. 3: A drawing of a second exemplary embodiment of a desublimator according to the invention in longitudinal section. Fig. 4: A drawing of a third exemplary embodiment of a desublimator according to the invention in cross-section along the inlet surface of the inlet. Fig. 5: A longitudinal section drawing of a fourth exemplary embodiment of a desublimator according to the invention. Fig. 6: A perspective view of a desublimator without a guide plate, according to a first comparative example, showing the velocities of the gas mixture flow in the direction of the longitudinal axis of the flow channels on the surface shown at the beginning of the loading process. The surface shown lies on the uppermost surface of the desublimation zone. Fig. 7: A perspective view of a fifth exemplary embodiment of the desublimator according to the invention. Fig. 5, where the velocities of the gas mixture flow in the direction of the longitudinal axis of the flow channels on the shown surface are depicted at the beginning of the loading process. The shown surface lies in the uppermost surface of the desublimation zone. Fig. 8: A perspective view of a sixth exemplary embodiment of the desublimator according to the invention. Fig. 5, where the velocities of the gas mixture flow in the direction of the longitudinal axis of the flow channels on the shown surface are depicted at the beginning of the loading process. The shown surface lies in the uppermost surface of the desublimation zone. Fig. 9: A perspective view of a seventh exemplary embodiment of the desublimator according to the invention. Fig. 5, where the velocities of the gas mixture flow in the direction of the longitudinal axis of the flow channels on the shown surface are depicted at the beginning of the loading process. The shown surface lies in the uppermost surface of the desublimation zone. Fig. 10: A perspective view of an eighth exemplary embodiment of the desublimator according to the invention. Fig. 5, where the velocities of the gas mixture flow in the direction of the longitudinal axis of the flow channels on the shown surface are depicted at the beginning of the loading process. The shown surface lies in the uppermost surface of the desublimation zone. Fig. 11: A perspective view of a ninth exemplary embodiment of the desublimator according to the invention. Fig. 5, where the velocities of the gas mixture flow in the direction of the longitudinal axis of the flow channels on the shown surface are depicted at the beginning of the loading process. The shown surface lies in the uppermost surface of the desublimation zone. Fig. 12: A perspective view of a tenth exemplary embodiment of the desublimator according to the invention. Fig. 5, where the velocities of the gas mixture flow in the direction of the longitudinal axis of the flow channels on the shown surface are depicted at the beginning of the loading process. The shown surface lies in the uppermost surface of the desublimation zone. List of reference symbols used: 1 desublimator 2 Entrance 3 Gas inlet distribution room 4. Desublimation zone 5 Gas outlet room 6 Outlet 7 Housing wall 8a First guide plate 8b Second guide plate 8c Third guide plate 9 Inlet area 10 inlet nozzles 11 outlet nozzles 12 outlet area 17 Additional outlet nozzle with a drain valve A ED Distance between the desublimation zone and the inlet nozzle A T Distance between the inlet nozzle and the housing wall B Width of the desublimator D equivalent diameter g gravity vector H Height of the desublimator L Length of the desublimator

[0067] Fig. Figure 1 shows a first exemplary embodiment of a desublimator 1 according to the invention with a length L in longitudinal section, wherein the lower right in the Fig. 1 the gravity vector g by an arrow and at the bottom left in the Fig. 1 the xy-coordinate system is represented.

[0068] The desublimator 1 has a horizontal longitudinal axis that is perpendicular to the longitudinal axis of the flow channels of the desublimation zone 4. The desublimator 1 has an inlet 2 with an inlet nozzle 10, through which a gas mixture flow containing at least one gas component to be desublimated flows into the gas inlet distribution chamber 3 of the desublimator 1 during a loading process. A virtual inlet area 9 is shown with dashed lines, indicating the virtual gas passage area, which is located in the main flow direction at the rearmost edge of the inlet nozzle 10. The distance A TThe distance between the inlet surface 9 and the housing wall 7 is defined. The housing wall 7 serves as the outer boundary of the desublimator 1. A desublimation zone 4 with temperature-controlled flow channel walls separates the gas inlet distribution chamber 3 from a gas outlet chamber 5. The desublimation zone is connected to the gas inlet distribution chamber 3 in such a way that, during the loading process, the gas mixture flow can pass from the gas inlet distribution chamber 3 to the desublimation zone 4. Furthermore, the desublimation zone 4 is connected to a gas outlet chamber 5 in such a way that, during the loading process, the gas mixture flow can pass from the desublimation zone 4 to the gas outlet chamber 5. An outlet 6 is arranged at the gas outlet chamber 5 so that, during the loading process, the gas mixture flow can exit the desublimator 1.For this purpose, an outlet surface 12 is provided on the housing wall 7, with an outlet nozzle 11 arranged around the outlet surface 12.

[0069] The desublimation zone 4 preferably has a volume in the range of 1 to 100 m³. 3 Three guide vanes 8a, 8b, 8c are arranged in the gas inlet distribution chamber 3 such that the gas mixture flows more uniformly through the flow channels during the loading process. The gas mixture should flow through as large a proportion of the total surface area of ​​all flow channel walls in the desublimation zone 4 as possible, so that it flows from the gas inlet distribution chamber 3 towards the gas outlet chamber 5. This provides the largest possible surface area for desublimation.

[0070] The maximum velocity at which the flow channels of the desublimation zone 4 are traversed should be as close as possible to the mean velocity through the flow channels to prevent rapid clogging of individual channels. Furthermore, backflow of the treated gas mixture from the gas outlet chamber 5 towards the gas inlet distribution chamber 3 should be avoided as much as possible to prevent a significant pressure drop across the desublimation zone 4. An additional outlet nozzle 17 with a drain valve, which could be, for example, a sealing cap, is also provided. During the loading process, the drain valve is closed, preventing any gas mixture from flowing out of the additional outlet nozzle 17. During a melting process, however, the drain valve is open, allowing the generated melt to flow out of the desublimator.Typically, this additional outlet nozzle 17 is located at the lowest point of the gas outlet space, so that the melt can flow to the additional outlet nozzle 17 due to gravity.

[0071] Fig. Figure 2 shows a cross-section of the first exemplary embodiment of a desublimator 1 according to the invention. Fig. 1, where the desublimator 1 has a height H and a width B. In the Fig. Figure 2 shows the zy coordinate system in the lower left. The cross-section shows the housing wall 7, the gas inlet distribution chamber 3, the desublimation zone 4, the at least three guide vanes 8a, 8b and 8c, and the distance A. ED between the desublimation zone 4 and the inlet surface 9, the gas outlet space 5, the outlet surface 12 and the inlet surface 9 with its diameter D are shown.

[0072] Fig. Figure 3 shows a longitudinal section of a second exemplary embodiment of a desublimator 1 according to the invention, in partial view, showing only those parts of the desublimator 1 that are arranged in the main flow direction up to the inlet surface of the desublimation zone 4. The desublimator 1 is, as in the first embodiment according to Fig. 1 oriented.

[0073] The desublimator 1 has a horizontal longitudinal axis that is perpendicular to the longitudinal axis of the flow channels of the desublimation zone 4. The desublimator 1 has an inlet 2 with a diameter D and an inlet nozzle 10, through which a gas mixture flow containing at least one gas component to be desublimated flows into the gas inlet distribution chamber 3 of the desublimator 1 during a loading process. An inlet surface 9 is shown with dashed lines, indicating the gas passage area, which is located in the main flow direction at the rearmost edge of the inlet nozzle 10. The distance A T defines the distance between the inlet surface 9 and the housing wall 7. Here, the housing wall 7 serves as the outer boundary of the desublimator 1. The distance A ED defines the distance between the inlet area 9 and the desublimation zone 4.

[0074] According to the invention, three guide plates 8a, 8b and 8c are arranged in the gas inlet distribution chamber 3, which in this embodiment are at least partially located in the inlet nozzle 10. The distance A is defined for the first guide plate 8a. E-LB,a the distance between the inlet surface 9 and the first point of the first guide vane 8a in the main flow direction, wherein the distance A e-LB,a is dimensioned along the longitudinal axis of the desublimator (1). The distance A is defined accordingly for the second guide plate 8b. E-LB,b the distance between the inlet surface 9 and the first point of the second guide vane 8b in the main flow direction, wherein the distance A E-LB,b is dimensioned along the longitudinal axis of the desublimator (1). And furthermore, the distance A is defined accordingly for the third guide plate 8c. E-LB,cthe distance between the inlet surface 9 and the first point of the third guide vane 8c in the main flow direction, wherein the distance A E-LB,c is measured along the longitudinal axis of the desublimator (1).

[0075] The distance H LB,w-a defines the distance between the first guide plate 8a and the wall of the inlet nozzle 10. Similarly, the distance H defines LB,c-w the distance between the third guide plate 8c and the wall of the inlet nozzle 10. The distance H LB,a-b defines the distance between the first guide plate 8a and the second guide plate 8b. Similarly, the distance H defines LB,b-c the distance between the second guide plate 8b and the third guide plate 8c.

[0076] The first guide plate 8a is angled by an internal angle α a inclined to the inlet surface of the desublimation zone 4, wherein the interior angle α ais dimensioned between the longitudinal axis of the first guide plate 8a and the longitudinal axis of the flow channel walls of the desublimation zone 4.

[0077] The second guide plate 8b is angled by an internal angle α b inclined to the inlet surface of the desublimation zone 4, wherein the interior angle α b is dimensioned between the longitudinal axis of the second guide plate 8b and the longitudinal axis of the flow channel walls of the desublimation zone 4.

[0078] The third guide plate 8c is angled by an internal angle α c inclined to the inlet surface of the desublimation zone 4, wherein the interior angle α c is dimensioned between the longitudinal axis of the third guide plate 8c and the longitudinal axis of the flow channel walls of the desublimation zone 4.

[0079] Fig. Figure 4 shows a cross-section along the inlet surface 9 of a third exemplary embodiment of a desublimator 1 according to the invention, wherein five guide plates 8a, 8b, 8c, 8d and 8e are positioned such that they divide the inlet surface 9 into equally sized areas EF a , EF b , EF c , EF d and EF e and EF f subdivide. In this embodiment, the guide plates 8a, 8b, 8c, 8d extend in their transverse axis even beyond the inlet surface 9 to the opposite housing side walls 7. In addition, the respective distance A E-LB,a , A E-LB,b , A E-LB,c and A E-LB,d between the inlet surface 9 and the edge of the corresponding guide plate 8a, 8b, 8c, 8d arranged first in the main flow direction is zero.

[0080] Regardless of this embodiment, it is generally possible for the guide plates 8a, 8b, 8c, 8d to extend substantially to the edge of the inlet surface 9 within the inlet nozzle 10, and to increase in their transverse axis outside the inlet nozzle 10, preferably to substantially the opposite housing side walls. Examples

[0081] The following examples of the loading process of a desublimator are modeled using numerical fluid dynamics simulations. These simulations are also frequently referred to as "Computational Fluid Dynamics (CFD)." The software ANSYS Fluent was used for this purpose, which can be found at https: / / www.ansys.com / de-de / products / fluids / ansys-fluent (accessed on October 25, 2023). ANSYS Fluent is a comprehensive simulation software used for modeling, simulating, and optimizing fluid dynamics processes, systems, and components in industry.

[0082] The following examples are based on a steady-state simulation using the RANS turbulence model. The default settings of Fluent Solver version 22.1 are used. Example 1

[0083] A thermodynamic simulation of an embodiment of the method for operating a desublimator 1 according to the invention. Fig. 5 was carried out in Fluent. This example 1 differs from the first embodiment according to the invention only in the positioning of the inlet nozzle and in the number, dimensions, positioning and orientation of the guide vanes. Fig. 1.

[0084] The length L of the desublimator 1 is 7.24 m, the width B of the desublimator 1 is 2.85 m, the height H of the desublimator 1 is 4.56 m, the height of the desublimation zone is 1.7 m, the diameter D of the circular inlet area 9 is 0.79 m, the diameter of the circular outlet area 12 is 0.79 m, the internal volume of the gas inlet distribution chamber is 23.8 m³ 3 and the internal volume of the gas outlet chamber is 24.9 m³ 3 .

[0085] The ratio between the inlet area of ​​desublimation zone 4 and the distance between the inlet and outlet areas of desublimation zone 4 is 13.1 [m²]. 2 / m].

[0086] The desublimation zone 4 has a volume of 32.58 m³ 3 The surface area of ​​all flow channel walls in desublimation zone 4 is 5000 m². 2 This provides a cooling area of ​​5000 m² for the loading process. 2 A heating surface of 5000 m² is available before and for the melting process. 2 before.

[0087] In the simulation, however, the finned tubes are simplified due to the computational power required, so that a porous zone represents the four finned tube bundles. The pressure drop across the flow channels of desublimation zone 4 is thus calculated efficiently. The porous zone is described in more detail in section 6.2.3 of the ANSYS Fluent User's Guide dated February 17, 2016, provided by ANSYS, Inc. on their website "https: / / www.ansys.com / ". Such a porous zone is also illustrated on page 44 of the website Computational Fluid Dynamics (CFD) of Chemical Processes - Google Books (accessed September 5, 2022). Here, the flow directions of the gas mixture within the flow channels, which would otherwise deviate from the longitudinal axis of the flow channels, are at least predominantly aligned by a corresponding pressure drop so that these flow directions also point in the direction of the longitudinal axis of the flow channels.

[0088] In this example 1, the inlet surface 9 is arranged flush with the housing wall 7 of the desublimator 1, whereby after Fig. 3 the distance A T is equal to zero.

[0089] The distance A ED after Fig. 3 is 0.310 m and the distance A E-LB after Fig. 3 is 0.000 m for each of the six arranged guide plates.

[0090] The diameter D of the circular inlet area 9 is 0.797 m.

[0091] According to the invention, Fig. 5 six guide plates 8a, 8b, 8c, 8d, 8e and 8f are arranged in the gas inlet distribution chamber 3, each having its first arranged edge in the inlet surface 9 or on the edge of the inlet surface 9 in the main flow direction.

[0092] Five guide vanes 8a, 8b, 8c, 8d and 8e of the six guide vanes 8a, 8b, 8c, 8d, 8e and 8f are positioned such that they divide the inlet area 9 into equally sized areas EF a , EF b , EFc , EF a , EF e and EF f subdivide, as is also the case for five guide plates in Fig. 4 is shown.

[0093] In this example 1, however, the points to Fig. 4. The five guide vanes each extend a length along their transverse axis depending on the position of their first edge in the inlet surface 9. Thus, the length of the transverse axis of each of the five guide vanes is limited to the edge of the inlet surface 9.

[0094] Essentially, the guide vanes 8a, 8b, 8c, 8d, 8e and 8f should preferably be wider than the jet of the incoming gas mixture flow into the desublimation zone 4. Otherwise, the jet could flow around the guide vanes 8a, 8b, 8c, 8d, 8e and 8f.

[0095] Furthermore, the six guide vanes 8a, 8b, 8c, 8d, 8e and 8f provide sufficient surface area for the gas mixture flow to flow along it. Thus, the gas mixture flow is essentially guided along the guide vanes 8a, 8b, 8c, 8d, 8e and 8f.

[0096] However, the distances between the adjacent guide plates 8a, 8b, 8c, 8d, 8e and 8f should not become too small so that the pressure loss across the desublimator does not increase significantly.

[0097] As a rule, therefore, not too many guide plates 8 should be installed.

[0098] A distance between adjacent guide plates 8 of at least 0.10 * D is recommended, where D corresponds to the equivalent diameter of a circle with the same area as the inlet surface 9.

[0099] The lengths of the guide vanes 8a, 8b, 8c, 8d, 8e and 8f along their longitudinal axis have the following values: Guide plate 8a: 0.749 m Guide plate 8b: 0.683 m Guide plate 8c: 0.621 m Guide plate 8d: 0.533 m Guide plate 8e: 0.337 m Guide plate 8f: 0.797 m

[0100] The guide plate 8f is fixed at the uppermost point of the inlet surface 9, wherein the edge of the guide plate 8f that is first arranged in the main flow direction is fixed at the uppermost point of the inlet surface 9 such that the uppermost point is located in the middle of the edge.

[0101] Furthermore, a shorter length is used for the lowest guide plate 8e, since the lowest guide plate 8f would otherwise extend too close to the desublimation zone 4 and could reduce a uniform distribution along the upstream surface of the desublimation zone 4.

[0102] The preferred lengths of the guide vanes 8a, 8b, 8c, 8d, 8e, and 8f are in the range of 3 to 5 times the equivalent diameter of the inlet area 9. These values ​​are usually sufficient to redirect the gas mixture flow without a significant increase in pressure loss. Vanes that are too long are more complex to arrange and secure. Furthermore, they also represent thermal mass, which may necessitate heating for one or more guide vanes 8a, 8b, 8c, 8d, 8e, and 8f in certain cases.

[0103] Furthermore, the six guide vanes 8a, 8b, 8c, 8d, 8e and 8f are arranged with their respective interior angles α. a , α b , α c , α d , α e and α f according to Fig. 3 aligned such that their respective extensions along their corresponding longitudinal axis intersect the inlet surface of the desublimation zone 4 in such a way that the inlet surface of the desublimation zone 4 is divided into six equal areas FL a , FL b , FLc , FL d , FL e and FL f is subdivided.

[0104] Since the six guide vanes 8a, 8b, 8c, 8d, 8e, and 8f do not extend to the opposite housing side walls 7, the six guide vanes 8a, 8b, 8c, 8d, 8e, and 8f are each fictitiously extended along their transverse axes as if the individual guide vanes 8a, 8b, 8c, and 8d did extend to the opposite housing side walls 7. This ensures that the six equally sized surfaces each extend to the opposite housing side walls 7.

[0105] The following specifies the values ​​of the interior angles in degrees, where the respective interior angle α a , α b , α c , α d , α e , α f the following angle is obtained between the longitudinal axis of the respective guide plate 8a, 8b, 8c, 8d, 8e and 8f and the longitudinal axis of the flow channel walls: αa=81.6 αb=81.1 αc=79.4 αd=76.1 αe=69.0 αf=81.6

[0106] Larger interior angles α a , α b , α c , α d , α e , α f Larger angles, preferably in the range of 70 to 89°, are required if the area of ​​the upstream surface of the desublimation zone 4 located at the rear of the desublimator's longitudinal axis is to be subjected to increased flow, whereas smaller internal angles, preferably in the range of 20 to 50°, are required if the area of ​​the upstream surface of the desublimation zone 4 located at the front of the desublimator's longitudinal axis is to be subjected to increased flow.

[0107] The simulation yields the following results: A gas mixture flow with a mass flow rate of 30 t / h, an absolute pressure of 1.086 bar, and a temperature of 178 °C is fed to the desublimator 1 through an inlet 2. The mass flow of the gas mixture contains PSA as the gas component to be desublimated at a concentration of 3 wt%, resulting in a molar mass of 29.7 g / mol. Under the prevailing thermodynamic conditions, the dynamic viscosity of the gas mixture is 2.26 × 10⁻⁵ Pa s. The housing wall has a temperature of 178 °C.

[0108] The pressure loss between inlet 2 and outlet 6 of the desublimator 1 is 3.42 mbar.

[0109] The inflow area is 11.9 m² 2The gas mixture flows from the gas inlet distribution chamber 3 to the gas outlet chamber 5. A reverse flow occurs over the remaining portion of the inlet area. The maximum velocity of the gas mixture flow through the desublimation zone 4 is 5.5 m / s, and the average velocity of the gas mixture flow through the desublimation zone 4 is 0.46 m / s.

[0110] The achieved uniform distribution of the gas mixture flow through the flow channels is evaluated based on the following results of the flow simulation: Fig. Figure 7 shows the upstream area of ​​the desublimation zone 4, where the velocities of the gas mixture flow in the direction of the longitudinal axis of the flow channels at the beginning of the loading process are shown, and where the upstream area is located in the uppermost surface of the desublimation zone 4. At the beginning of the loading process, desublimation at the flow channel walls of the desublimation zone 4 occurs predominantly in an area located on the opposite side of the inlet surface 9. As the loading process progresses, the location of desublimation shifts towards the inlet surface 9.

[0111] Velocities whose velocity vectors are oriented in the direction of the main flow of the gas mixture through the flow channels of desublimation zone 4 are shown in black if the velocity magnitude is greater than or equal to 10 m / s. Velocities whose velocity vectors are oriented in the opposite direction to the main flow of the gas mixture through the flow channels of desublimation zone 4 are shown in white if the velocity magnitude is greater than 0 m / s.

[0112] From the comparison of the two Fig. 6 and Fig. 7 shows that in a desublimator 1 according to the invention, after Fig. 7 the gas mixture flows through a larger area of ​​the desublimation zone 4 towards the gas outlet chamber 5. Furthermore, the guide vanes 8a, 8b, 8c, 8d, 8e, and 8f according to the invention cause the area of ​​the gas inlet distribution chamber 3 located further back in the main flow direction to exhibit velocity directions across the entire width B of the desublimator 1 that are oriented towards the gas outlet chamber 5. This prevents higher velocities in the flow channels of the desublimation zone 4, and the pressure drop across the desublimation zone 4 is correspondingly lower. A strong flow through individual flow channels would lead to their rapid clogging. In extreme cases, this could even result in desublimation at the flow channel walls only being partially successful due to the high velocities of the gas mixture flow.The guide vanes 8a, 8b, 8c, 8d, 8e and 8f reduce excessive velocity and the resulting backflows in adjacent flow channels, thereby avoiding or at least partially avoiding the aforementioned effects.

[0113] Furthermore, the gas mixture flow entering desublimation zone 4 is broken up and distributed section by section onto the surface of the desublimator. Six individual jets strike six corresponding sections of the inflow surface of desublimation zone 4.

[0114] The guide vanes ensure that the individual jets do not flow perpendicularly onto the inflow surface of desublimation zone 4, but rather parallel to it. This further improves the flow. Example 2

[0115] Example 2 according to the invention corresponds to Example 6 except for the length of the guide plates 8a, 8b, 8c, 8d, 8e and 8f in their longitudinal axis.

[0116] The lengths of the guide vanes 8a, 8b, 8c, 8d, 8e and 8f along their longitudinal axis have the following values: Guide plate 8a: 0.950 m Guide plate 8b: 0.889 m Guide plate 8c: 0.824 m Guide plate 8d: 0.704 m Guide plate 8e: 0.454 m Guide plate 8f: 0.996 m

[0117] The inflow area is 10.6 m² 2 The gas flows from gas inlet distribution chamber 3 to gas outlet chamber 5. A backflow occurs in the remaining portion of the inlet area.

[0118] The pressure loss between inlet 2 and outlet 6 of the desublimator 1 is 4.52 mbar.

[0119] Fig. Figure 8 shows the flow area of ​​the desublimation zone 4 analogous to the flow area of ​​the desublimation zone 4 from Example 1.

[0120] From the comparison of the two Fig. 6 and Fig. 8 shows that in a desublimator 1 according to the invention, Fig. 8. The gas mixture flows through a larger area of ​​the desublimation zone 4 towards the gas outlet chamber 5. Furthermore, the guide vanes 8a, 8b, 8c, 8d, 8e, and 8f according to the invention cause the area of ​​the gas inlet distribution chamber 3 located further back in the main flow direction to exhibit velocity directions across the entire width B of the desublimator 1 that are oriented towards the gas outlet chamber 5. This prevents higher velocities in the flow channels of the desublimation zone 4, and the pressure drop across the desublimation zone 4 is correspondingly lower. A strong flow through individual flow channels would lead to their rapid clogging. In extreme cases, this could even result in desublimation at the flow channel walls only being partially successful due to the high velocities of the gas mixture flow.The guide vanes 8a, 8b, 8c, 8d, 8e and 8f reduce excessive velocities and the resulting backflows in adjacent flow channels, thereby avoiding or at least partially avoiding the aforementioned effects. Example 3

[0121] Example 3 according to the invention corresponds to Example 6 except for the length of the guide plates 8a, 8b, 8c, 8d, 8e and 8f in their longitudinal axis.

[0122] The lengths of the guide vanes 8a, 8b, 8c, 8d, 8e and 8f along their longitudinal axis have the following values: Guide plate 8a: 1.554 m Guide plate 8b: 1.506 m Guide plate 8c: 1.452 m Guide plate 8d: 1.182 m Guide plate 8e: 0.454 m Guide plate 8f: 1.594 m

[0123] The inflow area is 10.5 m² 2The gas flows from gas inlet distribution chamber 3 to gas outlet chamber 5. A backflow occurs in the remaining portion of the inlet area.

[0124] The pressure loss between the inlet 2 and the outlet 6 of the desublimator 1 is 4.48 mbar.

[0125] Fig. Figure 9 shows the flow area of ​​the desublimation zone 4 analogous to the flow area of ​​the desublimation zone 4 from Example 1.

[0126] From the comparison of the two Fig. 6 and Fig. 9 shows that in a desublimator 1 according to the invention, after Fig. 9 the gas mixture flows through a larger area of ​​the desublimation zone 4 towards the gas outlet chamber 5. Furthermore, the guide vanes 8a, 8b, 8c, 8d, 8e, and 8f according to the invention cause the area of ​​the gas inlet distribution chamber 3 located further back in the main flow direction to exhibit velocity directions oriented towards the gas outlet chamber 5 across the entire width B of the desublimator 1. This prevents higher velocities in the flow channels of the desublimation zone 4, and the pressure drop across the desublimation zone 4 is correspondingly lower. A strong flow through individual flow channels would lead to their rapid clogging. In extreme cases, this could even result in desublimation at the flow channel walls only being partially successful due to the high velocities of the gas mixture flow.The guide vanes 8a, 8b, 8c, 8d, 8e and 8f reduce excessive velocities and the resulting backflows in adjacent flow channels, thereby avoiding or at least partially avoiding the aforementioned effects. Example 4

[0127] Example 4 according to the invention corresponds to Example 6 except for the number and length of the guide plates and the fact that the guide plate 8f is shifted upwards by 0.05 * D, whereby the guide plate 8f is arranged above the inlet nozzle.

[0128] The lengths of the three guide vanes 8c, 8d and 8f along their longitudinal axis have the following values: Guide plate 8c: 0.824 m Guide plate 8d: 0.704 m Guide plate 8f: 0.996 m

[0129] The inflow area is 12.6 m² 2The gas flows from gas inlet distribution chamber 3 to gas outlet chamber 5. A backflow occurs in the remaining portion of the inlet area.

[0130] The pressure loss between inlet 2 and outlet 6 of the desublimator 1 is 3.74 mbar.

[0131] Fig. Figure 10 shows the flow area of ​​the desublimation zone 4 analogous to the flow area of ​​the desublimation zone 4 from Example 1.

[0132] From the comparison of the two Fig. 6 and Fig. 10 shows that in a desublimator 1 according to the invention, Fig. 10. The gas mixture flows through a larger area of ​​the desublimation zone 4 towards the gas outlet chamber 5. Furthermore, the guide vanes 8c, 8d, and 8f according to the invention cause the area of ​​the gas inlet distribution chamber 3 located further back in the main flow direction to exhibit velocity directions oriented towards the gas outlet chamber 5 across the entire width B of the desublimator 1. This prevents higher velocities in the flow channels of the desublimation zone 4, and the pressure drop across the desublimation zone 4 is correspondingly lower. A strong flow through individual flow channels would lead to their rapid clogging. In extreme cases, this could even result in desublimation at the flow channel walls only being partially successful due to the high velocities of the gas mixture flow.The guide vanes 8c, 8d and 8f reduce excessive velocities and the resulting backflows in adjacent flow channels, thereby avoiding or at least partially avoiding the aforementioned effects. Example 5

[0133] Example 5 according to the invention corresponds to Example 6 except for the number of guide vanes and the fact that guide vane 8f has been shifted upwards by 0.05 * D, whereby guide vane 8f is arranged above the inlet nozzle. D here corresponds to the equivalent diameter of a circle with the same area as the inlet surface 9. In this Example 5, three guide vanes 8c, 8d and 8f are used.

[0134] The pressure loss between inlet 2 and outlet 6 of the desublimator 1 is 3.69 mbar.

[0135] The inflow area is 12.0 m² 2The gas flows from gas inlet distribution chamber 3 to gas outlet chamber 5. A backflow occurs in the remaining portion of the inlet area.

[0136] Fig. Figure 11 shows the flow area of ​​the desublimation zone 4 analogous to the flow area of ​​the desublimation zone 4 from Example 1.

[0137] From the comparison of the two Fig. 6 and Fig. 11 shows that in a desublimator 1 according to the invention, Fig. 11 the gas mixture flows through a larger area of ​​the desublimation zone 4 towards the gas outlet chamber 5. Furthermore, the guide vanes 8c, 8d, and 8f according to the invention cause the area of ​​the gas inlet distribution chamber 3 located further back in the main flow direction to exhibit velocity directions oriented towards the gas outlet chamber 5 across the entire width B of the desublimator 1. This prevents higher velocities in the flow channels of the desublimation zone 4, and the pressure drop across the desublimation zone 4 is correspondingly lower. A strong flow through individual flow channels would lead to their rapid clogging. In extreme cases, this could even result in desublimation at the flow channel walls only being partially successful due to the high velocities of the gas mixture flow.The guide vanes 8c, 8d and 8f reduce excessive velocities and the resulting backflows in adjacent flow channels, thereby avoiding or at least partially avoiding the aforementioned effects. Example 6

[0138] Example 6 according to the invention corresponds to Example 1 except for the length of the guide plates 8a, 8b, 8c, 8d, 8e and 8f in their longitudinal axis and the interior angles of the guide plates 8a, 8b, 8c, 8d, 8e and 8f.

[0139] The lengths of the guide vanes 8a, 8b, 8c, 8d, 8e and 8f along their longitudinal axis have the following values: Guide plate 8a: 0.747 m Guide plate 8b: 0.676 m Guide plate 8c: 0.603 m Guide plate 8d: 0.475 m Guide plate 8e: 0.230 m Guide plate 8f: 0.797 m

[0140] The following specifies the values ​​of the interior angles in degrees, where the respective interior angle α a , α b, α c , α d , α e , α f the following angle is obtained between the longitudinal axis of the respective guide plate 8a, 8b, 8c, 8d, 8e and 8f and the longitudinal axis of the flow channel walls: αa=80.9 αb=79.7 αc=76.3 αd=66.6 αe=42.2 αf=80.9

[0141] The pressure loss between inlet 2 and outlet 6 of the desublimator 1 is 4.40 mbar.

[0142] The inflow area is 10.6 m² 2 The gas flows from gas inlet distribution chamber 3 to gas outlet chamber 5. A backflow occurs in the remaining portion of the inlet area.

[0143] Fig. Figure 12 shows the flow area of ​​the desublimation zone 4 analogous to the flow area of ​​the desublimation zone 4.

[0144] From the comparison of the two Fig. 6 and Fig. 12 shows that in a desublimator 1 according to the invention, Fig. 12 the gas mixture flows through a larger area of ​​the desublimation zone 4 towards the gas outlet chamber 5. Furthermore, the guide vanes 8c, 8d, and 8f according to the invention cause the area of ​​the gas inlet distribution chamber 3 located further back in the main flow direction to exhibit velocity directions oriented towards the gas outlet chamber 5 across the entire width B of the desublimator 1. This prevents higher velocities in the flow channels of the desublimation zone 4, and the pressure drop across the desublimation zone 4 is correspondingly lower. A strong flow through individual flow channels would lead to their rapid clogging. In extreme cases, this could even result in desublimation at the flow channel walls only being partially successful due to the high velocities of the gas mixture flow.The guide vanes 8c, 8d and 8f reduce excessive velocities and the resulting backflows in adjacent flow channels, thereby avoiding or at least partially avoiding the aforementioned effects. Comparative example 1

[0145] In contrast to example 1, no guide vanes are present. All other features of desublimator 1, as well as the process parameters for the loading process, remain the same. A simulation was also performed here using the Fluent software.

[0146] The achieved uniform distribution of the gas mixture flow through the individual flow channels is evaluated based on the following results of the flow simulation: The pressure loss between the inlet 2 and the outlet 6 of the desublimator 1 is 3.2 mbar.

[0147] The desublimation zone 4 is supplied with gas from the gas inlet distribution chamber 3 via a flow surface, the flow surface corresponding to the uppermost surface of the desublimation zone 4.

[0148] The inflow area is 8.7 m² 2 The gas mixture flows from the gas inlet distribution chamber 3 to the gas outlet chamber 5. A reverse flow occurs in the remaining portion of the inlet area. The maximum velocity of the gas mixture flow through the desublimation zone 4 is 11.2 m / s and the average velocity of the gas mixture flow through the desublimation zone 4 is 0.46 m / s.

[0149] The upstream surface of the desublimation zone 4 is in Fig. 6 shown, wherein the velocities of the gas mixture flow at the beginning of the loading process are shown on the inflow surface in the direction of the longitudinal axis of the flow channels, and wherein the inflow surface is located in the uppermost surface of the desublimation zone 4.

[0150] At the beginning of the loading process, desublimation on the flow channel walls of desublimation zone 4 occurs predominantly in an area located on the opposite side of the inlet surface 9. As the loading process progresses, the location of desublimation shifts towards the inlet surface 9.

[0151] The inlet surface exhibits a gradient between the central axis and the housing walls 7, the gradient being determined by the uneven velocity distribution. Desublimation occurs particularly near the housing wall 7. In the area of ​​the inlet surface 9, hardly any desublimation takes place at the beginning of the charging process.

[0152] Velocities whose velocity vectors are oriented in the direction of the main flow of the gas mixture through the flow channels of desublimation zone 4 are shown in black if the velocity magnitude is greater than or equal to 10 m / s. Velocities whose velocity vectors are oriented in the opposite direction to the main flow of the gas mixture through the flow channels of desublimation zone 4 are shown in white if the velocity magnitude is greater than 0 m / s. Values ​​in the intermediate range are shown according to the scale as follows. Fig. 6 shown. QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] DE 3407104 A1

[0005] DE 102015101398 A1

[0006] Cited non-patent literature

[0000] https: / / www.ansys.com / de-de / products / fluids / ansys-fluent (accessed on 25.10.2023

[0081] Chapter 6.2.3 in the ANSYS Fluent User's Guide dated February 17, 2016, published by ANSYS, Inc. on their website "https: / / www.ansys.com /

[0087] Page 44 of the website Computational Fluid Dynamics (CFD) of Chemical Processes - Google Books (accessed on 05.09.2022

[0087]

Claims

[1] Discontinuously operated desublimator (1) for removing at least one gas component to be desublimated from a gas mixture flow comprising a housing wall (7) as an outer boundary, an inlet nozzle (10) on the housing wall (7) for supplying the gas mixture flow into the desublimator (1), an outlet (6) on the housing wall (7) for discharging the treated gas mixture flow from the desublimator (1), a desublimation zone (4) with temperature-controlled flow channel walls, wherein the flow channel walls are temperature-controlled such that during a loading process the at least one gas component to be desublimated desublimates at the flow channel walls, and that during a subsequent melting process the at least one gas component desublimated in the loading process melts at the flow channel walls, a gas inlet distribution chamber (3) located between the inlet (2) and the desublimation zone (4), and a gas outlet space (5) located between the outlet (6) and the desublimation zone (4), characterized by , that at least a first guide plate (8a), a second guide plate (8b) and a third guide plate (8c) are arranged in the gas inlet distribution chamber (3) for the uniform distribution of the gas mixture flow through the flow channels that result from the flow channel walls of the desublimation zone (4), and wherein at least three guide plates (8a, 8b, 8c) each have a distance (H LB, a-b , H LB , b-c ) to their adjacent guide plate or to their adjacent guide plates in the range of 0.01 to 0.9 * D, preferably in the range of 0.10 to 0.50 * D, wherein D corresponds to the equivalent diameter of a circle with the same area as the inlet surface (9). [2] Desublimator (1) according to claim 1, wherein the first guide plate (8a) has a distance (H LB , w-a ) to the wall of the inlet nozzle (10) in the range of 0 to 1 * D, preferably in the range of 0 to 0.3 * D, and the third guide plate (8c) has a distance (H LB , c-w ) to the wall of the inlet nozzle (10) in the range of 0 to 1 * D, preferably in the range of 0 to 0.3 * D, wherein D corresponds to the equivalent diameter of a circle with the same area as the inlet surface (9). [3] Desublimator (1) according to one of the preceding claims, wherein the at least three guide plates (8a, 8b, 8c) each extend with their transverse axis at least to one of the two opposite housing side walls (7), preferably to the two opposite housing side walls of the desublimator (1). [4] Desublimator (1) according to claim 1 or 2, wherein the at least three guide plates (8a, 8b, 8c) each have a length along their transverse axis in the range of 0.1 to 5 * D, preferably in the range of 0.1 to 3 * D, wherein D corresponds to the equivalent diameter of a circle with the same area as the inlet surface (9). [5] Desublimator (1) according to one of the preceding claims, wherein the at least three guide plates (8a, 8b, 8c) each have a length along their longitudinal axis in the range of 0.1 to 9 * D, preferably in the range of 0.1 to 3 * D and particularly preferably in the range of 0.2 to 1 * D, wherein L corresponds to the length of the longitudinal axis of the desublimator (1). [6] Desublimator (1) according to one of the preceding claims, wherein the at least three guide plates (8a, 8b, 8c) each have an internal angle (α a , α b , α c ) in the range of 0 to 90°, preferably in the range of 5 to 85°, wherein the respective interior angle (α) a , αb , α c ) between the longitudinal axis of the respective guide plate (8a, 8b, 8c) and the longitudinal axis of the flow channel walls. [7] Desublimator (1) according to claim 6, wherein the at least three guide plates (8a, 8b, 8c) each have an internal angle (α a , α b , α c ) exhibiting a design such that the extension of the respective guide plates (8a, 8b, 8c) in the direction of their longitudinal axis intersects with the inlet surface of the desublimation zone (4) such that the inlet surface of the desublimation zone (4) is divided into equally sized areas (FL a , FL b , FL c , FL d ) is subdivided. [8] Desublimator (1) according to one of the preceding claims, wherein the at least three guide plates (8a, 8b, 8c) are each arranged such that the inlet surface (9) intersects with the respective guide plates (8a, 8b, 8c) or with the extensions of the respective guide plates (8a, 8b, 8c) along its longitudinal axis such that the inlet surface (9) is divided into equally sized areas (EF a , EF b , EF c ) is subdivided, wherein in the case of more than three guide plates (8a, 8b, 8c) the further guide plates may also be fixed at the edge of the inlet surface (9) or may be fixed outside the inlet surface (9) in such a way that their extensions along their longitudinal axis do not intersect the inlet surface (9). [9] Desublimator (1) according to any of the preceding claims, wherein the at least three guide plates (8a, 8b, 8c) each have a straight, wavy, folded or bent, flat profile, preferably a lamellar profile. [10] Desublimator (1) according to one of the preceding claims, wherein at least one guide plate of the at least three guide plates (8a, 8b, 8c) has a porosity in the range of 0 to 80%, preferably in the range of 0 to 50%. [11] Desublimator (1) according to any one of the preceding claims, wherein the inlet surface (9) has a distance (A T ) to the housing wall (7) in the range of 0 to 10.0 * D, preferably in the range of 0.2 to 0.6 * D, where D corresponds to the equivalent diameter of a circle with the same area as the inlet surface (9). [12] Desublimator (1) according to any one of the preceding claims, wherein the desublimation zone (4) has a distance (A ED ) to the inlet surface (9) in the range of 0.01 to 3 * D, preferably in the range of 0.1 to 0.5 * D, wherein D corresponds to the equivalent diameter of a circle with the same area as the inlet surface (9). [13] Desublimator (1) according to one of the preceding claims, wherein the at least three guide plates (8a, 8b, 8c) each have a distance (A E-LB, a , A E-LB, b , A E-LB, c ) to the inlet surface (9) in the range of 0 to 300 mm, wherein the respective distance (A E-LB, a , A E-LB, b , A E-LB, c ) is measured along the longitudinal axis of the desublimator (1). [14] Desublimator (1) according to one of the preceding claims, wherein the desublimator (1) has a horizontal longitudinal axis oriented perpendicular to the longitudinal axis of the flow channels of the desublimation zone (4), and the gas inlet distribution chamber (3) is arranged above the desublimation zone (4). [15] Desublimator (1) according to one of the preceding claims, wherein the flow channel walls are formed by the outer walls of a tube bundle, a finned tube, a finned tube bundle, a lamellar body, a honeycomb body and / or a plate body.

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