Discontinuously operated desublimator with at least one perforated sheet

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 (2) 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 one first perforated plate (8) is 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), • whose geometric center of gravity is a distance (A T ) to the desublimation zone (4) in the range from 0 to A max , preferably in the range of 0 to 0.5 * A max , and particularly preferably in the range of 0.03 to 0.3 * A max exhibits, wherein A max corresponds to the distance between the inlet surface (9) of the inlet (2) and the desublimation zone (4), and • wherein the at least first perforated sheet (8) has a porosity in the range of 5 to 50%, preferably in the range of 10 to 30%, particularly preferably in the range of 10 to 20% and most preferably in the range of 5 to 20%.

Description

[0001] The invention relates to a discontinuously operated desublimator for removing at least one gas component to be desublimated from a gas mixture flow, comprising 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, at least one gas component to be desublimated desublyzes at the flow channel walls, and during a subsequent melting process, at least one gas component desublimated during the loading process melts at the flow channel walls. Furthermore, the desublimator comprises 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 obtained by desublimating the gas component on the cooled fins. In a subsequent melting process, the gas component desublimated on 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, necessitating more frequent regeneration of the desublimator, even though its maximum loading capacity has not yet been reached. The desublimator is typically regenerated through the melting process and an optional subsequent cooling process.

[0004] German patent DE 3407104 A1 discloses batch-operated desublimators for separating products from gas mixtures. These desublimators 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 greater parasitic heat losses to the environment, as the desublimator is only heated or cooled externally. This is especially true for larger desublimators with an internal volume of, for example, more than 1 m³.3 However, 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.

[0005] 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.

[0006] 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.

[0007] 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 12.

[0008] 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.

[0009] According to the invention, at least one first perforated plate is arranged in the gas inlet distribution chamber for the uniform distribution of the gas mixture flow through the flow channels resulting from the flow channel walls of the desublimation zone, the geometric center of which is at a distance A T to the desublimation zone in the range from 0 to A max , preferably in the range of 0 to 0.5 * A max and especially preferred in the range of 0.03 to 0.3 * A max exhibits, wherein A max the distance between the inlet surface of the inlet and the desublimation zone corresponds, and wherein the at least first perforated sheet has a porosity in the range of 5 to 50%, preferably in the range of 10 to 30% and particularly preferably in the range of 10 to 20%.

[0010] The first or subsequent perforated plates 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 flow 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.

[0011] 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 less. Consequently, the pressure drop between the inlet and outlet of the desublimator according to the invention also increases less during the loading process, and the desublimator can therefore be regenerated at longer intervals.Furthermore, compared to a desublimator without a perforated plate, 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 loss between the inlet and the outlet of the desublimator, whereby the desublimator according to the invention with at least one first perforated plate achieves a greater loading capacity at the same pressure loss.

[0012] 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.

[0013] 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.

[0014] 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.

[0015] 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.

[0016] 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.

[0017] 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.

[0018] 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.

[0019] 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.

[0020] 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.

[0021] 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].

[0022] 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.

[0023] The more inlet area is available, the less likely increased desublimation at the flow channel walls in the area of ​​the inlet area of ​​the desublimation zone is to lead to a significantly greater pressure loss or even a blockage.

[0024] In order for a desublimator to be designed to be cost-efficient 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 [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].

[0025] 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 flow channel walls of the desublimation zone are tempered accordingly by the heat transfer between the flow channel walls of the desublimation zone and the outer, flowable fluid line(s), whereby the heat transfer naturally also takes place through the intermediate housing wall.

[0026] If a coolant flows through the inner or outer fluid line(s) during the loading process, the walls of the flow channels are cooled due to heat conduction between the flow channel walls and the fluid line(s), allowing at least one gas component 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.

[0027] 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.

[0028] 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.

[0029] 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.

[0030] 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.

[0031] 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.

[0032] 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.

[0033] 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 of one or more desublimated gas components is reached on the flow channel walls of the desublimation zone. Here, the loading is understood as the deposited mass of one or more desublimated gas components on the flow channel walls.

[0034] 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.

[0035] 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.

[0036] 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.

[0037] In this document, the term "perforated sheet" 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. Generally, a gas mixture can only flow through the holes of the perforated sheet. An example of a possible exception would be a gap between the perforated sheet and the housing wall of a desublimator, through which a gas mixture could also flow. The perforated sheet can also be heated, for example, by mounting it on the housing side walls of a desublimator in such a way that sufficient heat can flow from the housing side walls to the perforated sheet. A heating element for the perforated sheet, such as an electric heater in contact with it, is also conceivable.

[0038] In this document, the term "hole spacing" defines the distance between two adjacent holes, measured from hole center to hole center.

[0039] In this document, the term "perforated area" defines the area of ​​a hole in the perforated sheet.

[0040] In this document, the term "total surface area of ​​the perforated sheet" refers to the surface of the perforated sheet including its perforated areas.

[0041] In this document, the term "free area" defines the summed area of ​​all perforated surfaces of the perforated sheet.

[0042] In this document, the term "relative free area of ​​the perforated sheet" defines the ratio between the free area and the total surface area of ​​the perforated sheet. For example, a 100 mm x 100 mm perforated sheet has 100 holes, where each hole has a perforation area of ​​10 mm². 2 Therefore, the total area of ​​all perforated surfaces of the perforated sheet is 1000 mm². 2The total surface area of ​​the perforated sheet, including the perforated areas, is 10000 mm². 2 This results in a relative free area of ​​the perforated sheet of 1000 / 10000 = 0.1.

[0043] In this document, the term "porosity of the perforated sheet" defines the ratio between the free area and the total surface area of ​​the perforated sheet. The "porosity of the perforated sheet" thus corresponds to the "relative free area of ​​the perforated sheet".

[0044] 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.

[0045] In a preferred embodiment of the desublimator according to the invention, the distance between the geometric center of gravity of the perforated sheet and the desublimation zone corresponds to at least twice the distance A. min, which results from the arithmetic mean of the distances between the directly adjacent holes of the at least first perforated sheet. In this embodiment, the geometric center of gravity of the at least first perforated sheet is therefore located at a distance from the desublimation zone in the range of 2.0 * A min up to 1.0 * A max , preferably in the range of 2.0 * A min up to 0.5 * A max , and especially preferred in the range of 3.0 * A min up to 0.3 * A max on, where A max corresponds to the distance between the inlet surface of the inlet and the desublimation zone.

[0046] In a particularly preferred embodiment of the desublimator according to the invention, the distance between the geometric center of gravity of the perforated sheet and the desublimation zone corresponds to at least three times the distance A. min, which results from the arithmetic mean of the distances between the directly adjacent holes of the at least first perforated sheet. In this embodiment, the geometric center of gravity of the at least first perforated sheet is therefore located at a distance from the desublimation zone in the range of 3.0 * A min up to 1.0 * A max preferably in the range of 3.0 * A min up to 0.5 * A max on, where A max corresponds to the distance between the inlet surface of the inlet and the desublimation zone.

[0047] In a preferred embodiment of the desublimator according to the invention, the distance between the geometric center of gravity of the perforated sheet and the desublimation zone corresponds to at least three times the distance A. min, which results from the arithmetic mean of the distances between the directly adjacent holes of the at least first perforated sheet. In this embodiment, the geometric center of gravity of the at least first perforated sheet is therefore located at a distance from the desublimation zone in the range of 3.0 * A min up to 1.0 * A max preferably in the range of 3.0 * A min up to 0.5 * A max , and especially preferred in the range of 5.0 * A min up to 0.3 * A max on, where A max corresponds to the distance between the inlet surface of the inlet and the desublimation zone.

[0048] In a particularly preferred embodiment of the desublimator according to the invention, the distance between the geometric center of gravity of the perforated sheet and the desublimation zone corresponds to at least five times the distance A. min, which results from the arithmetic mean of the distances between the directly adjacent holes of the at least first perforated sheet. In this embodiment, the geometric center of gravity of the at least first perforated sheet is therefore located at a distance from the desublimation zone in the range of 5.0 * A min up to 1.0 * A max , preferably in the range of 5.0 * A min up to 0.5 * A max on, where A max corresponds to the distance between the inlet surface of the inlet and the desublimation zone.

[0049] In a preferred embodiment of the desublimator according to the invention, the distance between the geometric center of gravity of the perforated sheet and the desublimation zone corresponds to at least five times the distance A. min, which results from the arithmetic mean of the distances between the directly adjacent holes of the at least first perforated sheet. In this embodiment, the geometric center of gravity of the at least first perforated sheet is therefore located at a distance from the desublimation zone in the range of 5.0 * A min up to 1.0 * A max , preferably in the range of 5.0 * A min up to 0.5 * A max , and especially preferred in the range of 10.0 * A min up to 0.3 * A max on, where A max corresponds to the distance between the inlet surface of the inlet and the desublimation zone.

[0050] In a particularly preferred embodiment of the desublimator according to the invention, the distance between the geometric center of gravity of the perforated sheet and the desublimation zone corresponds to at least five times the distance A. min, which results from the arithmetic mean of the distances between the directly adjacent holes of at least the first perforated sheet. This means that the geometric center of gravity of at least the first perforated sheet has a distance to the desublimation zone in the range of 12 * A min up to 30 * A min on, as long as the value is 30*A min is smaller than A max and especially preferred is the value 30*A min is less than 0.5*A max .

[0051] The three preferred embodiments described above have the advantage that optimization takes place between the following two factors: 1: The distance between the perforated sheet and the desublimation zone: The greater the distance, the more homogeneous the flow of the gas mixture to the flow channel walls becomes, as the individual jets from the holes of the perforated sheet decrease with increasing distance from the perforated sheet. 2: The distance between the perforated sheet and the inlet surface 9: The closer the perforated plate is to the inlet surface, the greater the risk of flow reversal within the plate due to a jet pumping effect. This effect can be explained by the high velocities along the perforated plate 9, which lead to a local pressure drop. If the pressure at the outlet of the flow channel walls is greater than the pressure at the perforated plate, this results in flow reversal. Additionally, an insufficient space above the perforated plate can reduce the uniform distribution of the gas mixture flow.

[0052] In a preferred embodiment of the desublimator according to the invention, the at least first perforated plate extends in its width substantially to the two opposing housing side walls of the desublimator. Preferably, the at least first perforated plate has a distance from the walls of the desublimator in the range of 0 to 10 mm, and particularly preferably a distance from the walls of the desublimator in the range of 0 to 1 mm. This offers the advantage that the gas mixture flow is distributed less unevenly over the desublimation zone, thus avoiding the risk of the gas mixture flow predominantly flowing laterally past the perforated plate.

[0053] In a preferred embodiment of the desublimator according to the invention, the at least first perforated plate has a width-related distance from the housing side walls of the desublimator in the range of 0 to 10 mm, preferably in the range of 0 to 1 mm. This offers the advantage that the gas mixture flow is distributed less unevenly over the desublimation zone and the risk of the gas mixture flow predominantly flowing laterally past the perforated plate is avoided. Here, the width of the perforated sheet runs parallel along the transverse axis of the desublimator, with the transverse axis running perpendicular to the main axis of the flow channel walls.

[0054] In a preferred embodiment of the desublimator according to the invention, the at least first perforated plate covers substantially the entire desublimation zone. The at least first perforated plate is spaced from the walls of the desublimator at a distance of 0 to 10 mm, preferably 0 to 1 mm. This offers the advantage that the gas mixture flow is distributed less unevenly over the desublimation zone, thus avoiding the risk of the gas mixture flow predominantly flowing laterally past the perforated plate.

[0055] In a preferred embodiment of the desublimator according to the invention, in the case of several perforated sheets, a distance of 0 to 0.50 * Amax, preferably 0 to 0.25 * Amax, is provided between the respective adjacent perforated sheets, wherein A maxThis corresponds to the distance between the inlet area and the desublimation zone. This offers the advantage that the gas mixture flow can initially distribute itself more evenly after passing through one perforated plate before flowing through the next. This prevents direct flow from one hole to the next hole of the next perforated plate, resulting in a more even distribution of the gas mixture flow at the inlet of the desublimation zone.

[0056] In a preferred embodiment of the desublimator according to the invention, the holes of the at least first perforated plate have different equivalent diameters, wherein the equivalent diameter corresponds to the diameter of a circle of the same area, and wherein the equivalent diameter of the individual holes is preferably in the range of 0.3 to 50.0 mm, particularly preferably in the range of 1.0 to 25.0 mm, and most preferably in the range of 5 to 20.0 mm. This offers the advantage that each location at the inlet of the desublimation zone can be locally optimized with respect to uniform distribution by adapting the equivalent diameter of the respective hole of the perforated plate to the gas mixture flow.

[0057] In a particularly preferred embodiment of the desublimator according to the invention, the at least first perforated sheet has different equivalent diameters and / or different hole spacings and / or different porosities. This offers the advantage that each location at the inlet of the desublimation zone can be locally optimized with respect to uniform distribution by adapting the equivalent diameter of the respective hole in the perforated sheet to the gas mixture flow.

[0058] In a preferred embodiment of the desublimator according to the invention, the holes of the at least first perforated plate located at a distance from the inlet surface in the range of 0.0 mm to L / 2 have a larger equivalent diameter than the more widely spaced holes of the perforated plate, where L corresponds to the length of the longitudinal axis of the gas inlet distribution chamber. Instead of the distance of L / 2, another distance such as L / 3, L / 4, or L / 5 can also be selected, wherein the respective dividers 3, 4, or 5 define the number of regions on the perforated plate, and the holes of the perforated plate can have a different equivalent diameter per region.

[0059] Furthermore, instead of the distance of L / 2, another distance such as a distance in the range of 0.1 to 0.9 * L can be chosen.

[0060] This offers the advantage that the gas mixture flow through the desublimation zone can be optimized independently in a front and a rear area in the main flow direction of the gas inlet distribution chamber.

[0061] In a further preferred embodiment of the desublimator according to the invention, the holes of the at least first perforated plate each have an equivalent diameter that is dimensioned as a function of the distance between the inlet surface (9) and the respective hole. Preferably, the dependence of the respective equivalent diameter on the distance represents a continuous gradient. This offers the advantage that the gas mixture flow through the desublimation zone can be optimized independently of one another in a front and a rear region in the main flow direction of the gas inlet distribution chamber.

[0062] In a preferred embodiment of the desublimator according to the invention, the at least first perforated sheet (8) has circular, elongated, elliptical, oval, rectangular, or polygonal holes. This offers the advantage that the holes can be efficiently produced in the perforated sheet and that, in the event of desublimation at a hole edge, the gas mixture flow does not immediately become impermeable to the hole in the perforated sheet.

[0063] In a preferred embodiment of the desublimator according to the invention, the number of holes in the at least first perforated sheet is in the range of 100 to 15000 per m². 2 -Perforated sheet metal surface, preferably in the range of 1000 to 4000 per m² 2 -perforated sheet area, and the holes preferably correspond to the pattern of an equilateral triangle.

[0064] This offers the advantage that, with comparable uniformity, the pressure loss across the perforated sheet is lower.

[0065] In principle, patterns other than an equilateral triangle are also conceivable, such as a general triangle, a quadrilateral or a polygon.

[0066] In a preferred embodiment of the desublimator according to the invention, the holes of the at least first perforated plate have a hole spacing in the range of 5 to 50 mm, preferably in the range of 20 to 40 mm. This offers the advantage that, in the event of desublimation at a hole edge, the hole of the perforated plate does not immediately become impermeable and the hole size can be adapted to the distance between the flow channel walls.

[0067] In a preferred embodiment of the desublimator according to the invention, several holes, preferably most holes, and particularly preferably all holes, of the at least first perforated sheet are arranged such that the flow channel walls projected perpendicularly onto the plane of the at least first perforated sheet form a pattern with the geometric centers of gravity of the holes, wherein in each of the pattern one of the projected flow channel walls overlaps with the nearest geometric center of gravity of the corresponding hole or has a maximum distance of up to 0.50 * D with the nearest geometric center of gravity of the corresponding hole. Mit or a distance of 0.50 * D from the nearest geometric center of gravity of the corresponding hole Mit exhibits, wherein D Mitthe equivalent diameter geometrically averaged over all flow channels, and wherein each individual equivalent diameter corresponds to a circle with the same area as the respective flow channel and each individual equivalent diameter is measured at the inlet of the desublimation zone.

[0068] This offers the advantage that the gas mixture flow can flow more evenly into the flow channels of the desublimation zone, since essentially the same hole area is present per projected flow channel, with each projected flow channel resulting from two adjacent projected flow channel walls.

[0069] 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 (4), and the gas inlet distribution chamber (3) is arranged above the desublimation zone (4). 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.

[0070] 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.

[0071] Another object of the invention is a method for operating a desublimator according to the invention.

[0072] 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.

[0073] 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.

[0074] 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.

[0075] This offers the advantage that the pressure drop does not become too high during maximum load operation of the loading 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 pump 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 being desublimated during operation and thus have to be switched off.

[0076] 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.

[0077] 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.

[0078] 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.

[0079] 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.

[0080] 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.

[0081] 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.%.

[0082] This has the advantage that at least one gas component to be desublimated is efficiently separated from the gas mixture flow.

[0083] 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 perforated sheet according to the invention. The holes in the perforated sheet each have a diameter of 10 mm and the hole spacing is 24 mm. Fig. 4: A drawing of a third exemplary embodiment of a perforated sheet according to the invention. The holes in the perforated sheet each have a diameter of 15 mm and the hole spacing is 36 mm. Fig. 5: A drawing of a fourth exemplary embodiment of a perforated sheet according to the invention. The holes in the perforated sheet are elongated and have a short side of 10.0 mm and a long side of 19.8 mm. The hole spacing is 24 mm. Fig. 6: A perspective view of a desublimator without a perforated 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 vector plot of the gas mixture flow velocities at the beginning of the loading process within a desublimator according to Fig. 6, which does not have a perforated sheet, where the vector plot is shown on the cross-sectional surface of the desublimator longitudinal section. Fig. 8: A perspective view of a fifth exemplary embodiment of the desublimator according to the invention with a perforated sheet according to the invention. Fig. 3, 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 sixth exemplary embodiment of the desublimator according to the invention with a perforated sheet according to the invention. Fig. 3, 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 a desublimator without a perforated plate, as in a second comparative example, showing the velocities of the gas mixture flow along 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. 11: A perspective view of a seventh exemplary embodiment of the desublimator according to the invention with a perforated sheet according to the invention. Fig. 3, 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 an eighth exemplary embodiment of the desublimator according to the invention with a perforated sheet according to the invention. Fig. 3, 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. 13: A perspective view of a ninth exemplary embodiment of the desublimator according to the invention with a perforated sheet according to the invention. Fig. 3, 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. 14: A perspective view of a tenth exemplary embodiment of the desublimator according to the invention with a perforated sheet according to the invention. Fig. 3 in cross-section, where the velocities on the shown surface are depicted at the beginning of the loading process. Fig. 15: A perspective view of an eleventh exemplary embodiment of the desublimator according to the invention with a perforated sheet according to the invention. Fig. 3 in cross-section, where the velocities on the shown surface are depicted at the beginning of the loading process. 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 8 perforated sheet metal 9 Inlet area 10 inlet nozzles 11 outlet nozzles 12 outlet area 17 Additional outlet nozzle with a drain valve A max Distance between the inlet surface and the desublimation zone A T Distance between the geometric center of gravity of at least one perforated sheet and the desublimation zone B Width of the desublimator D equivalent diameter g gravity vector H Height of the desublimator L Length of the desublimator

[0084] 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. Figure 1 shows the xy-coordinate system. 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. For this purpose, an inlet surface 9 is provided on the housing wall 7, with the housing wall 7 serving 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 flow 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 such 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 to allow the gas mixture flow to escape from the desublimator 1 during the loading process. 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. The desublimation zone 4 preferably has a volume in the range of 1 to 100 m³. 3A perforated plate 8 is 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 as possible of the total surface area of ​​all flow channel walls in the desublimation zone 4, so that the gas mixture flows from the gas inlet distribution chamber 3 towards the gas outlet chamber 5. This provides the largest possible surface area for desublimation. 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 flow 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. In this example, the perforated sheet 8 according to the invention is positioned in the gas inlet distribution chamber 7 at a distance A. T to desublimation zone 4 in the range of 0.03 to 0.3 * A max arranged, wherein A maxThe distance between the inlet surface 9 and the desublimation zone 4 corresponds to this. The perforated sheet 8 has a porosity of 15.7% and a hole spacing of 24 mm, with the hole pattern corresponding to equilateral triangles. Furthermore, the holes in the perforated sheet are circular and each hole diameter is 10 mm.

[0085] In general, the spacing between the holes of a perforated sheet 8 should preferably follow the pattern of the flow channel walls in the desublimator. In the examples disclosed here, these spacings range between 6 mm and 12 mm.

[0086] Other patterns may be suitable, for example, if the distance between two adjacent perforated plates in the desublimator varies. Here, the pattern can be adapted to the position of the channels. The equilateral triangle arrangement has the advantage of a small and more uniform distance between two holes on adjacent perforated plates.

[0087] Furthermore, an additional outlet nozzle 17 with a drain valve, which can be, for example, a sealing cap, is also present. 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 molten metal to flow out of the desublimator. Typically, this additional outlet nozzle 17 is located at the lowest point of the gas outlet chamber, so that gravity allows the molten metal to flow to it.

[0088] 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, and the perforated plate 8 with its distance A. T to the desublimation zone 4, the maximum distance Amax, which is defined by the distance between the inlet surface 9 and the desublimation zone 4, the gas outlet space 5, the outlet surface 12 and the inlet surface 9 with a diameter D are shown.

[0089] Fig. Figure 3 shows a perforated sheet 8 according to the invention, with each hole having a diameter of 10 mm and a hole spacing of 24 mm, wherein three holes form an equilateral triangle as a pattern. The parallel lines represent the flow channel walls. Thus, the holes are located between the flow channel walls when viewed perpendicularly from the gas inlet distribution chamber 3 onto the perforated sheet.

[0090] Fig. Figure 4 shows a perforated sheet 8 according to the invention, with each hole having a diameter of 15 mm and a hole spacing of 36 mm, wherein three holes form an equilateral triangle as a pattern. The parallel lines represent the flow channel walls. Thus, the holes are located centrally above the flow channel walls when viewed perpendicularly from the gas inlet distribution chamber 3 onto the perforated sheet.

[0091] Fig. Figure 5 shows a perforated sheet 8 according to the invention with elongated holes, the long side of which is 19.8 mm and the short side of which is 10.0 mm. The perforated sheet 8 has a hole spacing of 36 mm, with each set of three holes forming an equilateral triangle. The parallel lines represent the flow channel walls. Thus, the holes overlap between the flow channel walls when viewed perpendicularly from the gas inlet distribution chamber 3 onto the perforated sheet. Examples

[0092] 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 August 25, 2022). ANSYS Fluent is a comprehensive simulation software used for modeling, simulating, and optimizing fluid dynamics processes, systems, and components in industry.

[0093] 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

[0094] A thermodynamic simulation of an embodiment of the method for operating a desublimator 1 according to the invention. Fig. 1 was conducted in Fluent.

[0095] 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 .

[0096] 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].

[0097] The desublimation zone 4 has a volume of 32.58 m³ 3The 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.

[0098] 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 loss 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 / ". A similar porous zone is also illustrated on page 44 of the website Computational Fluid Dynamics (CFD) of Chemical Processes - Google Books (accessed September 5, 2022).

[0099] In this process, the flow directions of the gas mixture flow within the flow channels, which would deviate from the longitudinal axis of the flow channels, are at least predominantly aligned by a corresponding pressure loss so that these flow directions also point in the direction of the longitudinal axis of the flow channels.

[0100] The perforated sheet 8 according to the invention is located directly on the uppermost surface of the desublimation zone. The distance A T The distance between the perforated sheet 8 and the desublimation zone is therefore 0 mm.

[0101] The pressure loss of the perforated sheet 8 is calculated based on the detailed simulation of the perforated sheet 8 shown below, according to... Fig. 3 set. The perforated sheet 8 according to Fig. Hole 3 has a diameter of 10 mm and a spacing of 24 mm, with three holes forming an equilateral triangle pattern. The porosity of perforated sheet 8 is 15.7%.

[0102] The simulation yields the following results: A gas mixture flow with a mass flow rate of 150 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 8 wt.%. Under the prevailing thermodynamic conditions, the density of the gas mixture flow is 4.4 kg / m³. 3 and the dynamic viscosity of the gas mixture flow is 2.5*10 -5 Pa*s. The housing wall has a temperature of 178 °C.

[0103] The area-averaged pressure loss caused by the perforated sheet 8 is less than 100 Pa. The pressure loss between the inlet 2 and the outlet 6 of the desublimator 1 is 15.86 mbar.

[0104] The inflow area is 14 m² 2The 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 3.5 m / s, and the average velocity of the gas mixture flow through the desublimation zone 4 is 0.46 m / s.

[0105] 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 8 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 at 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 a region 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. Velocities whose velocity vectors are oriented in the direction of the main flow of the gas mixture through the flow channels of the desublimation zone 4 are shown in black if the velocity magnitude is greater than or equal to 10 m / s.The velocities whose velocity vectors are oriented in the opposite direction to the main flow direction of the gas mixture flow through the flow channels of the desublimation zone 4 are shown in white if the magnitude of the velocity is greater than 0 m / s.

[0106] From the comparison of the two Fig. 6 and Fig. Figure 8 shows that in a desublimator 1 according to the invention, the gas mixture flows through a larger area of ​​the desublimation zone 4 towards the gas outlet chamber 5. Furthermore, the perforated plate 8 according to the invention causes the area of ​​the gas inlet distribution chamber 3, located at the rear 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.A perforated sheet 8 reduces excessive velocity and the resulting backflows in adjacent flow channels, thereby avoiding or at least partially avoiding the aforementioned effects. Example 2

[0107] A thermodynamic simulation of an embodiment of the method for operating a desublimator 1 according to the invention. Fig. Example 1 was performed in Fluent. This Example 2 differs from Example 1 only in the material properties and the mass flow rate of the gas mixture. In this Example 2, a gas mixture 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 given 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 caused by the perforated plate 8 is less than 10 Pa. The pressure loss between the inlet 2 and the outlet 6 of the desublimator 1 is 3.3 mbar.

[0109] The upstream surface of the desublimation zone 4 is in Fig. 9 shown, wherein the velocities of the gas mixture flow in the direction of the longitudinal axis of the flow channels are shown at the beginning of the loading process, and wherein the inflow surface is located in the uppermost surface of the desublimation zone 4.

[0110] The inflow area is 14.7 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 2.7 m / s and the average velocity of the gas mixture flow through the desublimation zone 4 is 0.46 m / s.

[0111] 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. 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 12 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. 8 and Fig. Figure 9 shows that, despite the different material properties of the gas mixture flow, the perforated sheet 8 achieves a similar effect with regard to the uniform distribution of the gas mixture flow through the flow channels of the desublimation zone 4, whereby Fig. 8 the example 1 and Fig. 9 is assigned to example 2. In both Fig. 8 and Fig. 9. The loading process therefore takes place more evenly than in comparison example 1 with its associated Fig. 6. Only in the vicinity of inlet area 9 does the Fig. 8 and Fig. 9 an area through which the flow is in the opposite direction to the main flow direction.

[0113] Consequently, a perforated sheet 8 according to the invention also reduces excessive velocities of the gas mixture flow for other material properties or mass flows and thus also reduces backflows in adjacent flow channels.

[0114] It has been shown that the perforated sheet 8 according to the invention achieves its effect of better uniform distribution through the flow channels of the desublimation zone 4 under different material properties of the gas mixture flow or under different mass flow rates of the gas mixture flow. Example 8

[0115] Example 8 according to the invention corresponds to Example 2, wherein the porosity of the perforated sheet 8 is now 5%.

[0116] The inflow area is 17.04 m² 2 The gas flows from gas inlet distribution chamber 3 to gas outlet chamber 5. The pressure drop across the desublimator is 4.39 mbar and the maximum velocity is 0.65 m / s.

[0117] Fig. Figure 11 shows that almost the entire flow area from the gas inlet distribution chamber 3 to the gas outlet chamber 5 is exposed to the flow. Example 9

[0118] Example 9 according to the invention corresponds to Example 2, wherein the porosity of the perforated sheet 8 is now 20%.

[0119] The inflow area is 13.06 m² 2 The gas flows from gas inlet distribution chamber 3 to gas outlet chamber 5. The pressure drop across the desublimator is 3.25 mbar and the maximum velocity is 3.8 m / s.

[0120] Fig. Figure 12 shows that, except for the front area, the entire flow area from the gas inlet distribution chamber 3 to the gas outlet chamber 5 is exposed to the flow. Example 10

[0121] Example 10 according to the invention corresponds to Example 2, wherein the porosity of the perforated sheet 8 is now 50%.

[0122] The inflow area is 10.47 m² 2 The gas flows from gas inlet distribution chamber 3 to gas outlet chamber 5. The pressure drop across the desublimator is 3.17 mbar and the maximum velocity is 6.2 m / s.

[0123] Fig. Figure 13 shows that essentially only the rear half of the inflow area is exposed to the flow from the gas inlet distribution chamber 3 to the gas outlet chamber 5. Example 11

[0124] Example 11 according to the invention corresponds to Example 2, wherein the distance A T The distance between the perforated plate 8 and the desublimation zone 4 is now 24 mm. Since the diameter D of the circular inlet area 9 remains 0.79 m, this corresponds to 0.03 * D.

[0125] Fig. Figure 14 shows a cross-section through the desublimator, where the holes of the perforated plate 8 are in line with the flow channel walls. The flow can hardly spread between the perforated plate 8 and the desublimation zone 4, so that the jets originating from the holes of the perforated plate 8 are retained and flow through the flow channel walls of the desublimation zone 4 almost undisturbed. Example 12

[0126] Example 12 according to the invention corresponds to Example 2, wherein the distance A T The distance between the perforated plate 8 and the desublimation zone 4 is now 400 mm. Since the diameter D of the circular inlet area 9 remains 0.79 m, this corresponds to 0.5 * D.

[0127] Fig. Figure 15 shows a cross-section through the desublimator. The flow can distribute itself well between the perforated plate 8 and the desublimation zone 4, causing the jets emanating from the holes of the perforated plate 8 to become smaller with increasing distance from the perforated plate. Conclusion for the above examples:

[0128] If the perforated plate 8 rests either directly on the desublimation zone 4 or is located at a close distance from it, the individual jets from the perforated plate 8 enter the flow channels of the desublimation zone 4 at an excessively high velocity. The average jet velocity is the ideal, homogeneous velocity divided by the porosity. The lower the porosity, the greater the local velocity increase. At a porosity of 5%, this results in a factor of 20. These strong jets then lead to backflow areas between the jets and poor flow distribution. Therefore, at low porosities, a large distance between the perforated plate and the desublimation zone is preferable. At 50% porosity, even a small distance is usually sufficient.If the perforated sheet is too close to the inlet surface 9 and also has low porosity, then the flow direction through the perforated sheet 8 in the area of ​​the incoming jet can also be reversed due to the "jet pump effect". Comparative example 1

[0129] In contrast to example 1, there is no perforated sheet 8. All other features of the 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.

[0130] 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 inlet 2 and outlet 6 of the desublimator 1 is 15.68 mbar.

[0131] 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.

[0132] The inflow area is 8.6 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 13.4 m / s, and the average velocity of the gas mixture flow through the desublimation zone 4 is 0.46 m / s.

[0133] 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.

[0134] 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.

[0135] 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.

[0136] 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.

[0137] A vector plot of the velocity vectors of the gas mixture flow at the beginning of the loading process is generated inside the desublimator 1 in Fig. Figure 7 shows the vector plot on the cross-sectional area of ​​the desublimator longitudinal section. The length of the vectors is constant and therefore independent of the velocity.

[0138] It can be seen that, essentially in the left-hand area of ​​desublimation zone 4, indicated by a rectangular frame, the gas mixture flows completely through desublimation zone 4 towards gas outlet chamber 5. The curved, dashed line in desublimation zone 4 indicates the transition point where the velocity direction through the flow channels of desublimation zone 4 reverses. The more the curve slopes downward, the less the gas mixture flows through the flow channels of desublimation zone 4 towards gas outlet chamber 5. In the area to the right of the curve, the gas mixture flows from gas outlet chamber 5 through the flow channels of desublimation zone 4 towards gas inlet distribution chamber 3. Comparative example 2

[0139] In comparison to example 1, example 2 differs only in the material properties and the mass flow rate of the gas mixture. A simulation using the Fluent software was also performed here.

[0140] In this comparative example 2, 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 through an inlet 2 to the desublimator 1. 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.

[0141] 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.

[0142] 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.

[0143] The inflow area is 8.7 m² 2 The gas mixture flows from gas inlet distribution chamber 3 to gas outlet distribution 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.

[0144] The upstream surface of the desublimation zone 4 is in Fig. 10, 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.

[0145] 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.

[0146] 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.

[0147] 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 12 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. 10 shown.

[0148] Detailed simulations follow to investigate the influence of the exact perforated sheet geometry depending on the design of the desublimation zone: The detailed simulations were also calculated using the Fluent software. They each cover only a portion of the perforated sheet 8 with the flow channel walls of the desublimation zone 4 arranged beneath it, according to the Fig. 3 to 5. In addition to the inlet and outlet, symmetry boundary conditions are set at the other outer boundaries of the computational model. A simulation of the entire perforated sheet 8 and, accordingly, also the entire desublimation zone 4 would be too complex.

[0149] To demonstrate the potential for improving desublimation in desublimator 1, the heat transfer between the gas mixture flow and the flow channel walls was simulated in addition to the gas mixture flow.

[0150] For the simulations, a gas mixture flow is set with an inlet velocity of 0.5 m / s and an absolute pressure of 1.01325 bar at the outlet of the computational model. The gas mixture flow has a temperature of 178 °C at the inlet of the computational model. The flow channel walls are cooled to a temperature of 27 °C. Under the thermodynamic conditions present in the simulations, the density of the gas mixture flow is 0.81 kg / m³. 3 and the dynamic viscosity of the gas mixture flow is 2.26*10 -5 Pa*s.

[0151] The computational model has the following design: The length of the flow channel walls in the main flow direction is 0.35 m. The distance between the flow channel walls is 11 mm, and the wall thickness is 1 mm. The opening ratio, which corresponds to the ratio between the flowable inlet area and the total inlet area, is 91.67% at both the inlet and outlet. Detailed simulation example 3:

[0152] Detailed simulation example 3 examines a perforated sheet 8 according to the invention. Fig. 3, each with a hole diameter of 10 mm and a hole spacing of 24 mm, with each set of three holes forming an equilateral triangle. The porosity of the perforated sheet 8 is 15.7%. The perforated sheet 8 is positioned directly on the desublimation zone 4, resulting in a distance of exactly 0 mm between the perforated sheet 8 and the desublimation zone 4. Detailed simulation example 4:

[0153] Detailed simulation example 4 examines a perforated sheet 8 according to the invention. Fig. 3, each with a hole diameter of 10 mm and a hole spacing of 24 mm, with each set of three holes forming an equilateral triangle. The perforation of the perforated sheet 8 is 15.7%. The perforated sheet 8 is spaced 40 mm from the desublimation zone 4. Detailed simulation example 5:

[0154] Detailed simulation example 5 examines a perforated sheet 8 according to the invention. Fig. 4, each with a hole diameter of 15 mm and a hole spacing of 36 mm, with each set of three holes forming an equilateral triangle. The porosity of the perforated sheet 8 is 15.7%. The perforated sheet 8 is positioned directly on the desublimation zone 4, resulting in a distance of exactly 0 mm between the perforated sheet 8 and the desublimation zone 4. Detailed simulation example 6:

[0155] Detailed simulation example 6 examines a perforated sheet 8 according to the invention. Fig. 5 with elongated holes, each with a short and a long side. The short side of each elongated hole is 10 mm and the long side is 19.8 mm. The perforated sheet 8 has a hole spacing of 36 mm, with three holes forming an equilateral triangle pattern. The porosity of the perforated sheet 8 is 15.7%. The perforated sheet 8 is positioned directly on the desublimation zone 4, resulting in a distance of exactly 0 mm between the perforated sheet 8 and the desublimation zone 4. Detailed simulation example 7:

[0156] Detailed simulation example 7 examines a perforated sheet 8 according to the invention. Fig. 5 with elongated holes, each with a short and a long side. The short side of an elongated hole is 10 mm and the long side of the elongated hole is 19.8 mm. The perforated sheet 8 has a hole spacing of 36 mm, with three holes forming an equilateral triangle pattern. The porosity of the perforated sheet 8 is 15.7%. The perforated sheet 8 is spaced 40 mm from the desublimation zone 4. Results of the detailed simulations:

[0157] The reference for the detailed simulation examples listed in Table 1 is the perforated sheet 8 according to detailed simulation example 3, with a hole diameter of 10 mm and a hole spacing of 24 mm. The perforated sheet 8 is positioned directly on the desublimation zone 4, resulting in a distance of exactly 0 mm between the perforated sheet 8 and the desublimation zone 4. Table 1: Evaluation of detailed simulation examples 3 to 7. All values ​​are relative to the values ​​of detailed simulation example 3. Relativeraw-uni-alpha[-] Relative T mw, outlet [-] RelativerdT mW,inlet to outlet [-] RelativerPin[-] Beispiel 3 1,00 1,00 1,00 1,00 Beispiel 4 1,03 0,96 1,11 1,00 Beispiel 5 0,99 1,01 0,98 1,13 Beispiel 6 1,04 0,99 1,03 1,07 Beispiel 7 1,04 0,98 1,05 1,05

[0158] Here, “aw-uni-alpha” is the area-related “uniformity index” of the heat transfer coefficient. The relative aw-uni-alpha values ​​in Table 1 correspond to the ratio between the “uniformity index” of the heat transfer coefficient of the respective detailed simulation example and the “uniformity index” of the heat transfer coefficient according to detailed simulation example 3. The larger this value, the more uniform the desublimation takes place on the flow channel walls, and thus the desublimator 1 can be operated for a longer time and a larger quantity of the desublimating gas component can be deposited on the flow channel walls.

[0159] Here, “T” corresponds to mw, outlet“the mass-averaged temperature of the gas mixture flow at the outlet of the desublimation zone 4. The relative “T mw, outlet “Values ​​in Table 1 represent the ratio between the mass-averaged temperature of the gas mixture flow at the outlet of desublimation zone 4 of the relevant detailed simulation example and the mass-averaged temperature of the gas mixture flow at the outlet of desublimation zone 4 according to detailed simulation example 3. The lower this value, the better for the desublimation process, as more heat from the gas mixture is transferred to the flow channel walls.”

[0160] Here, "dT" corresponds to mw, inlet to outlet “The difference between the mass-averaged temperature of the gas mixture flow at the inlet of desublimation zone 4 and the mass-averaged temperature of the gas mixture flow at the outlet of desublimation zone 4. The relative “dT mw, inlet to outlet “The values ​​in Table 1 represent the ratio between the “dT mw ,inlet to outlet “Value of the relevant detailed simulation example and the “dT mw, inlet to outlet “Value of the detailed simulation example 3. The larger this value is, the better it is for the desublimation process, as more heat from the gas mixture is transferred to the flow channel walls.

[0161] Here, "P" corresponds to in “the absolute pressure at inlet 2 of the desublimator 1. The relative “P in “Values ​​in Table 1 represent the ratio between the absolute pressure at inlet 2 of desublimator 1 of the respective detailed simulation example and the absolute pressure at inlet 2 of desublimator 1 according to detailed simulation example 3. The lower the value, the better for the desublimation process, as there is less pressure loss in desublimator 1.”

[0162] Here, the specific values ​​of the detailed simulation example 3 are: a-uni-alpha [W / m 2 K] 0,581 T mw, outlet [K] 326,413 dT mw,inlet to outlet [K] 124,587 P in [Pa] 7,371 Conclusion:

[0163] Therefore, the perforated sheet 8, spaced 40 mm from the desublimation zone 4, as shown in detailed simulation example 4, is to be considered the preferred embodiment. This perforated sheet 8 has circular holes, each with a diameter of 10 mm and a spacing of 24 mm, with three holes forming an equilateral triangle pattern. The porosity of the perforated sheet 8 is 15.7%.

[0164] This perforated sheet 8 is best suited for installation in the desublimator 1 because the pressure loss is low and the mass-averaged temperature of the gas mixture flow at the outlet of the desublimation zone 4 is significantly lower than in the detailed simulation examples 3, 5, 6, and 7. The "aw-uni-alpha" value is also greater than 1, resulting in more uniform desublimation at the flow channel walls than in detailed simulation examples 3 and 5. 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

[0004] DE 102015101398 A1

[0005] Cited non-patent literature

[0000] Computational fluid dynamics (CFD)” was used for this purpose. The software ANSYS Fluent was used, which can be found on the website https: / / www.ansys.com / de-de / products / fluids / ansys-fluent (accessed on 25.08.2022)

[0092] 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 /

[0098] Page 44 of the website Computational Fluid Dynamics (CFD) of Chemical Processes - Google Books (accessed on 05.09.2022

[0098]

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 (2) 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 one first perforated plate (8) is 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), • whose geometric center of gravity is a distance (A T ) to the desublimation zone (4) in the range from 0 to A max , preferably in the range of 0 to 0.5 * A max , and particularly preferably in the range of 0.03 to 0.3 * A max exhibits, wherein A max corresponds to the distance between the inlet surface (9) of the inlet (2) and the desublimation zone (4), and • wherein the at least first perforated sheet (8) has a porosity in the range of 5 to 50%, preferably in the range of 10 to 30%, particularly preferably in the range of 10 to 20% and most preferably in the range of 5 to 20%. [2] Desublimator (1) according to claim 1, wherein the at least first perforated sheet (8) extends in its width to the two opposite housing side walls (7) of the desublimator (1) and preferably has a distance to the walls of the desublimator in the range of 0 to 10 mm and particularly preferably a distance in the range of 0 to 1 mm. [3] Desublimator (1) according to one of claims 1 or 2, wherein the at least first perforated sheet (8) covers the entire desublimation zone (4) and has a distance to the walls of the desublimator in the range of 0 to 10 mm, preferably in the range of 0 to 1 mm. [4] Desublimator (1) according to one of the preceding claims, wherein, in the case of several perforated sheets, there is a distance between the respective adjacent perforated sheets in the range of 0 to 0.50 * A max preferably in the range of 0 to 0.25* A max , results in, where A max corresponds to the distance between the inlet area (9) and the desublimation zone (4). [5] Desublimator (1) according to one of the preceding claims, wherein the holes of the at least first perforated sheet (8) have different equivalent diameters, wherein the equivalent diameter corresponds to the diameter of a circle of equal area, and wherein the equivalent diameter of the individual holes is preferably in the range of 0.3 to 50.0 mm, particularly preferably in the range of 1.0 to 25.0 mm and most preferably in the range of 5.0 to 20.0 mm. [6] Desublimator (1) according to claim 5, wherein the holes of the at least first perforated plate (8) which are located at a distance from the inlet surface (9) in the range of 0.0 mm to L / X mm have a larger equivalent diameter than the more widely spaced holes of the perforated plate (8), wherein L corresponds to the length of the longitudinal axis of the gas inlet distribution chamber (3) and X has a value in the range of 1.1 to 10.0 * L. [7] Desublimator (1) according to any of the preceding claims, wherein at least the first perforated sheet (8) has circular, elongated, elliptical, oval, rectangular or polygonal holes. [8] Desublimator (1) according to one of the preceding claims, wherein the number of holes of the at least first perforated sheet (8) is in the range of 100 to 15000 per m 2 -Perforated sheet metal surface, preferably in the range of 1000 to 4000 per m² 2 -perforated sheet area, and the holes preferably correspond to the pattern of an equilateral triangle. [9] Desublimator (1) according to one of the preceding claims, wherein the holes of the at least first perforated sheet (8) have a hole spacing in the range of 5 to 50 mm, preferably in the range of 20 to 30 mm. [10] Desublimator (1) according to one of the preceding claims, wherein several holes, preferably most holes, particularly preferably all holes, of the at least first perforated sheet (8) are arranged such that the flow channel walls projected perpendicularly onto the plane of the at least first perforated sheet (8) form a pattern with the geometric centers of gravity of the holes, wherein in the pattern one of the projected flow channel walls overlaps with the nearest geometric center of gravity of the corresponding hole or has a maximum distance of up to 0.50 * D with the nearest geometric center of gravity of the corresponding hole. Mit or a distance of 0.50 * D from the nearest geometric center of gravity of the corresponding holeMit exhibits, wherein D Mit the equivalent diameter geometrically averaged over all flow channels, wherein each individual equivalent diameter corresponds to a circle with the same area as the respective flow channel and each individual equivalent diameter is measured at the inlet of the desublimation zone (4). [11] 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). [12] 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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