Patent Description:
Conventional systems using a heat-transfer bed filled with ceramic material for exhaust gas purification suffer from various heat loses such as heat losses at the side walls of the heat-transfer bed or at the inlets and outlets of the heat-transfer bed for the exhaust gas. Additionally, such conventional systems suffer from a spatially varying pressure drop at the inlets of the heat-transfer bed for the exhaust gas. As a consequence, the flow distribution of the exhaust gas over the heat-transfer bed is uneven and causes an uneven temperature distribution in the heat-transfer bed, which may result in insufficient heating of the exhaust gas when passing the heat-transfer bed and, hence, negatively affect the purification of the exhaust gas.

Document <CIT> relates to a shaped body for tempering a fluid, which can be used, for example, to form a thermal bed of a regenerator. The shaped body has a block made of a heat-conducting material defined by a base and a height perpendicular to the base. The block has a plurality of cells in cross-section parallel to its base and these cells each have a cross-sectional shape parallel to the base in the form of a regular polygon. The block further includes a plurality of channels arranged essentially parallel to each other and to the vertical direction of the block, with each of the channels provided in a cell such that an inner wall exists between channels in adjacent cells.

Document <CIT> relates to a heat storage device designed to store thermal energy. The device consists of a container with a horizontal longitudinal axis and a thermal storage material. The container features a first opening for fluid inflow and outflow, a second opening located vertically opposite the first opening, and a fluid-impermeable plate inclined against the flow direction of the fluid.

There may be demand for improved purification of fluids such as exhaust gases.

The demand may be satisfied by the subject-matter of the appended claims.

According to a first aspect, the present disclosure provides a fluid purification device. The fluid purification device comprises a heat-transfer bed filled with heat storage material. Further, the fluid purification device comprises a first plenum attached to a first opening of the heat-transfer bed, and a second plenum attached to a second opening of the heat-transfer bed. The first opening and the second opening are arranged on opposite sides of the heat-transfer bed. Additionally, the fluid purification device comprises a heat blocking element arranged in the first plenum. The heat blocking element is spaced apart from the heat-transfer bed and is spaced apart from a housing of the first plenum. The heat blocking element extends beyond the first opening and is configured to limit heat emission from the heat storage material into the first plenum. The first plenum and the second plenum are configured to alternatingly supply fluid to the heat-transfer bed such that the fluid heats up and reacts while flowing through the heat storage material. During a time period in which one of the first plenum and the second plenum is configured to supply the fluid to the heat-transfer bed, the other one of the first plenum and the second plenum is configured to drain the reacted fluid from the heat-transfer bed.

According to a second aspect, the present disclosure provides a method for operating the above fluid purification device. The method comprises supplying fluid to the heat-transfer bed alternatingly through the first plenum and the second plenum such that the fluid heats up and reacts while flowing through the heat storage material. Additionally, the method comprises, during a time period in which one of the first plenum and the second plenum supplies the fluid to the heat-transfer bed, draining the reacted fluid from the heat-transfer bed through the other one of the first plenum and the second plenum.

The heat blocking element in the first plenum may allow to reduce heat loses at the first opening of the heat-transfer bed. Furthermore, the heat blocking element in the first plenum may allow for an improved flow distribution of the fluid over the heat-transfer bed such that a more even temperature distribution in the heat-transfer bed may be achieved. As a consequence, the purification of the fluid may be improved compared to conventional approaches.

According to some examples of the present disclosure, the fluid purification device further comprises another heat blocking element arranged in the second plenum. The other heat blocking element is spaced apart from the heat-transfer bed and is spaced apart from a housing of the second plenum. The other heat blocking element extends beyond the second opening and is configured to limit heat emission from the heat storage material into the second plenum. The other heat blocking element in the second plenum may allow to reduce heat loses at the second opening of the heat-transfer bed. Furthermore, the other heat blocking element in the second plenum may allow to further improve the flow distribution of the fluid over the heat-transfer bed such that a more even temperature distribution in the heat-transfer bed may be achieved. As a consequence, the purification of the fluid may be further improved compared to conventional approaches.

In some examples of the present disclosure, a gap formed between a boundary of the first opening and a surface of the heat blocking element facing the first opening acts as a nozzle for the fluid when flowing from the first plenum to the heat-transfer bed. This exemplary configuration may allow to support the generation of the improved flow distribution of the fluid in the heat-transfer bed.

According to some examples of the present disclosure, the surface of the heat blocking element extends substantially parallel to the first opening. This exemplary configuration may allow to define the width of the gap and, hence, to adjust the nozzle effect of the gap.

In some examples of the present disclosure, the heat-transfer bed comprises one or more protrusion formed at the boundary of the first opening for defining the gap between the surface of the heat blocking element and the boundary of the first opening. The one or more protrusion may allow to define the width of the gap and, hence, to adjust the nozzle effect of the gap.

According to some examples of the present disclosure, the heat blocking element comprises at least one movable element for adjusting the gap between the boundary of the first opening and at least part of the surface of the heat blocking element. In these examples, the fluid purification device further comprises at least one actuator configured to adjust, based on a temperature and/or a pressure and/or a differential pressure in the first plenum and/or time based and/or event based, a respective positioning and/or orientation of the at least one movable element relative to the boundary of the first opening. Changing the positioning and/or orientation of the at least one movable element relative to the boundary of the first opening may allow to adjust (control) the variation of the static pressure at the first opening in order to support the generation of the improved flow distribution of the fluid in the heat-transfer bed.

In alternative examples of the present disclosure, the heat blocking element is bendable for adjusting the gap between the boundary of the first opening and at least part of the surface of the heat blocking element. In these examples, the fluid purification device further comprises at least one actuator configured to exert, based on a temperature and/or a pressure and/or a differential pressure in the first plenum and/or time based and/or event based, a force on the heat blocking element for bending the heat blocking element. Adjusting the gap by bending the heat blocking element may allow to adjust (control) the variation of the static pressure at the first opening in order to support the generation of the improved flow distribution of the fluid in the heat-transfer bed.

In further alternative examples of the present disclosure, the heat blocking element comprises a bimetal structure configured to bend the heat blocking element based on a temperature in the first plenum for adjusting the gap between the boundary of the first opening and at least part of the surface of the heat blocking element. Adjusting the gap by means of the bimetal structure may allow to adjust (control) the variation of the static pressure at the first opening in order to support the generation of the improved flow distribution of the fluid in the heat-transfer bed.

According to some examples of the present disclosure, a surface of the heat blocking element facing the first opening is tilted with respect to the first opening. In these examples, the first plenum extends lengthwise along a first spatial direction such that the fluid travels through the first plenum along the first spatial direction during a time period in which the first plenum is configured to supply the fluid to the heat-transfer bed. A distance between the surface of the heat blocking element and the first opening increases along the first spatial direction. A distance between another opposite surface of the heat blocking element and a wall of the first plenum's housing decreases along the first spatial direction. The first opening and the wall of the first plenum's housing are arranged on opposite sides of the heat blocking element. Also this exemplary configuration may allow to support the generation of the improved flow distribution of the fluid in the heat-transfer bed.

In some examples of the present disclosure, the heat blocking element is substantially plate-shaped. The plate-shaped may allow simple implementation of the heat blocking element.

According to some examples of the present disclosure, the heat blocking element comprises another opposite surface facing a wall of the first plenum's housing. In these examples, the first opening and the wall of the first plenum's housing are arranged on opposite sides of the heat blocking element. The first plenum extends lengthwise along a first spatial direction such that the fluid travels through the first plenum along the first spatial direction during a time period in which the first plenum is configured to supply the fluid to the heat-transfer bed. A distance between the surface and the other surface of the heat blocking element increases along the first spatial direction. A distance between the other surface of the heat blocking element and the wall of the first plenum's housing decreases along the first spatial direction. Also this exemplary configuration may allow to support the generation of the improved flow distribution of the fluid in the heat-transfer bed.

In some examples of the present disclosure, the fluid purification device further comprises at least one actuator coupled to the heat blocking element. In these examples, the at least one actuator is configured to adjust, based on a temperature and/or a pressure and/or a differential pressure in the first plenum and/or time based and/or event based, a positioning and/or orientation of the heat blocking element's surface with respect to the first opening. Changing the positioning and/or orientation of the heat blocking element's surface may allow to adjust (control) the variation of the static pressure at the first opening in order to support the generation of the improved flow distribution of the fluid in the heat-transfer bed.

According to some examples of the present disclosure, a plurality of recesses for passthrough of the fluid are formed in the heat blocking element. The plurality of recesses extend from a surface of the heat blocking element facing the first opening to another opposite surface of the heat blocking element. The plurality of recesses may allow to support the generation of the improved flow distribution of the fluid in the heat-transfer bed.

In some examples of the present disclosure, the first plenum extends lengthwise along a first spatial direction such that the fluid travels through the first plenum along the first spatial direction during a time period in which the first plenum is configured to supply the fluid to the heat-transfer bed. In these examples, a respective size of the plurality of recesses for passthrough of the fluid and/or a number of recesses for passthrough per unit area increases along the first spatial direction. This exemplary configuration may allow to lower the effective resistance of the heat blocking element for the fluid when entering the heat-transfer bed and, hence, support the generation of the improved flow distribution of the fluid in the heat-transfer bed.

According to some examples of the present disclosure, the heat blocking element comprises one or more surface structure for controlling a flow direction and/or flow characteristics of the fluid locally. The one or more surface structure may allow to support the generation of the improved flow distribution of the fluid in the heat-transfer bed.

In some examples of the present disclosure, the other heat blocking element arranged in the second plenum may comprise one or more of the other features, or a selection of features as disclosed for the heat blocking element arranged in the first plenum as described in the sections above. In some preferred embodiments, the heat blocking element and the other heat blocking element are very much similar, analogous, identical and/or symmetric in their construction and features, especially the features disclosed for the heat blocking element in the sections above, to allow for an oscillating operation of the fluid purification device, by which one of the first and second plenum serves as entry whereas the other serves as exit for a fluid to be processed in the heat-transfer bed of the fluid purification device in alternating states/phases of operation.

In some examples of the present disclosure, the fluid purification device further comprises an electrical heater configured to heat the heat storage material to a predefined temperature. The electrical heater may allow to initially heat the ceramic material to the predefined temperature.

According to some examples of the present disclosure, catalyst material for lowering a reaction temperature of the fluid is arranged within the heat-transfer bed. Due to the catalyst material, the needed temperature for the reaction of the fluid may be lowered such that the fluid purification device may operate at lower temperatures.

In some examples of the present disclosure, the heat-transfer bed comprises a thermally insulating wall surrounding the heat storage material and extending between the first plenum and the second plenum. In these examples, the first opening and the second opening are formed in the thermally insulating wall. The thermally insulating wall may allow to minimize heat losses over the heat-transfer bed.

According to some examples of the present disclosure, the housing of the first plenum is at least partly formed of and/or is at least partly covered by a heat-insulating material. The heat-insulating material may allow to minimize heat loses over the housing of the first plenum.

When two elements A and B are combined using an "or", this is to be understood as disclosing all possible combinations, i.e. only A, only B as well as A and B, unless expressly defined otherwise in the individual case.

<FIG> and <FIG> schematically illustrate a sectional view of a fluid purification device <NUM> for purifying a fluid <NUM>. The fluid <NUM> may be or comprise one or more gaseous components or substances, one or more vapor components or substances, one or more liquid components or substances, and/or mixtures thereof. According to examples of the present disclosure, the fluid <NUM> may comprise exclusively gaseous components or substances. For example, the fluid <NUM> may be an exhaust gas or an exhaust air, wherein an exhaust air contains a higher proportion of oxygen compared to an exhaust gas. The fluid purification device <NUM> removes one or more impurity and/or one or more pollutant from the fluid <NUM> for purifying the fluid <NUM>. An impurity may be understood in this context as a substance in the fluid <NUM> that is not included in a desired (target) composition of the fluid <NUM>. A pollutant may be understood in this context as a substance that harms systems, animals, humans and/or the environment when occurring in a specific quantity or concentration (e.g. defined as mass of the pollutant per unit volume of the fluid <NUM> or as number of pollutant particles per unit volume of the fluid <NUM>). One or more impurity or pollutant contained in the fluid <NUM> may be combustible. For example, organic and/or inorganic impurities or pollutants may be removed from the fluid <NUM> by the fluid purification device <NUM>. The organic and/or inorganic impurities or pollutants may, e.g., be Volatile Organic Compounds (VOCs), solvents, nitrogen oxides (NOx), methane (CH<NUM>), sulfur oxides (SOx), hydrogen fluoride (HF), ammonia (NH<NUM>), hydrogen chloride (HCl), dioxins, furans or pollutants of the basic structure CxHyOz (C denotes carbon; H denotes hydrogen; O denotes oxygen; x, y, and z are natural numbers).

The fluid purification device <NUM> comprises a (e.g. single, i.e., exactly/only one) heat-transfer bed <NUM> filled with heat storage material (heat transfer material) <NUM>. The heat storage material <NUM> is material capable of storing and releasing heat. The heat storage material exhibits a certain (predefined) specific heat capacity and preferably a certain (predefined) heat transfer and/or transmission coefficient. For example, the heat storage material <NUM> may comprise or be ceramic material such as alumina porcelain, mullite, fireclay (chamotte), cordierite, zircon or a mixture thereof. However, the present disclosure is not limited thereto. Other types of ceramic material may be used as well. In some example, the heat storage material <NUM> may alternatively or additionally comprise or be concrete, stone, rock, metallic material or a mixture thereof. The heat storage material <NUM> may be packed structured or randomly in the heat-transfer bed <NUM> to form regular or irregular patterns (e.g. ceramic honeycombs, ceramic saddles or the like may be used).

The heat-transfer bed <NUM> comprises a thermally insulating wall <NUM> surrounding the heat storage material <NUM>. A first opening <NUM> and a second opening <NUM> are formed in the thermally insulating wall <NUM>. A first plenum <NUM> is attached to the first opening <NUM> of the heat-transfer bed <NUM>, and a second plenum <NUM> is attached to the second opening <NUM> of the heat-transfer bed <NUM>. The first opening <NUM> and the second opening <NUM> are arranged on opposite sides of the heat-transfer bed <NUM> such that the thermally insulating wall <NUM> extends between the first plenum <NUM> and the second plenum <NUM>.

The first plenum <NUM> and the second plenum <NUM> are configured to alternatingly supply the fluid <NUM> to the heat-transfer bed <NUM> such that the fluid <NUM> heats up and reacts while flowing through the heat storage material <NUM>. For example, the fluid <NUM> may be heat up and be subject to an oxidation process or a reduction process while flowing through the heat storage material <NUM>. The heat storage material <NUM> is configured to store heat released by the fluid <NUM> during and/or after the reaction. During a time period in which one of the first plenum <NUM> and the second plenum <NUM> is configured to supply the fluid <NUM> to the heat-transfer bed <NUM>, the other one of the first plenum <NUM> and the second plenum <NUM> is configured to drain the reacted fluid <NUM>' (i.e. the fluid after undergoing the reaction) from the heat-transfer bed <NUM>. Accordingly, a flow direction of the fluid <NUM> through the heat storage material <NUM> is periodically reversed (e.g. every <NUM> to <NUM> seconds).

<FIG> illustrates the fluid purification device <NUM> during a time period in which the first plenum <NUM> is configured to supply the fluid <NUM> to the heat-transfer bed <NUM> and the second plenum <NUM> is configured to drain the reacted fluid <NUM>' from the heat-transfer bed <NUM>. Accordingly, the fluid <NUM> flows from the top to the bottom of the heat-transfer bed <NUM> through the heat storage material <NUM>. Heat energy previously stored in the top part of the heat storage material <NUM> is used to heat up the fluid <NUM> and causes the fluid <NUM> to react. The heat storage material <NUM> at the bottom part recovers the excess heat energy from the reacted fluid <NUM>'. For example, as the fluid <NUM> passes from the top part to the bottom part of the heat storage material <NUM>, VOCs in the fluid <NUM> may get hot enough to undergo thermal oxidation to water vapor and carbon dioxide.

<FIG> illustrates the fluid purification device <NUM> during a time period in which the second plenum <NUM> is configured to supply the fluid <NUM> to the heat-transfer bed <NUM> and the first plenum <NUM> is configured to drain the reacted fluid <NUM>' from the heat-transfer bed <NUM>. Accordingly, the fluid <NUM> flows from the bottom to the top of the heat-transfer bed <NUM> through the heat storage material <NUM>. Heat energy previously stored in the bottom part of the heat storage material <NUM> is used to heat up the fluid <NUM> and causes the fluid <NUM> to react. The heat storage material <NUM> at the top part recovers the heat energy from the reacted fluid <NUM>'.

The periodic reversion of the flow direction of the fluid <NUM> through the heat storage material <NUM> may allow to maintain a high heat exchange efficiency of the heat storage material <NUM> (e.g. higher than <NUM> %). Accordingly, the fluid purification device <NUM> may recover substantially all the heat needed for sustaining a needed reaction temperature in the heat-transfer bed <NUM> (e.g. an oxidation temperature or a reduction temperature). For example, irrespective of the flow direction of the fluid <NUM> through the heat storage material <NUM>, a temperature of the reacted fluid <NUM>' may be less than <NUM> higher than that of the fluid <NUM> supplied to the heat-transfer bed <NUM> (e.g. the temperature may be only <NUM> to <NUM> higher). Further, the periodic reversion of the flow direction of the fluid <NUM> may allow to maintain a predetermined temperature profile of the heat-transfer bed <NUM> along the extension of the heat-transfer bed <NUM> between the first plenum <NUM> and the second plenum <NUM> (i.e. along the vertical extension of the heat-transfer bed in the example of <FIG> and <FIG>). In particular, the periodic reversion of the flow direction of the fluid <NUM> may allow to keep the hottest zone near a center plane of the heat-transfer bed <NUM> along the extension of the heat-transfer bed <NUM> between the first plenum <NUM> and the second plenum <NUM>.

During operation of the fluid purification device <NUM>, the heat storage material <NUM> may exhibit a predefined temperature suitable for thermal reaction of the fluid <NUM>. For example, the predefined temperature may be more than approx. <NUM>, <NUM> or <NUM>. The fluid purification device <NUM> may according to some examples of the present disclosure comprise an electrical heater (not illustrated in <FIG> and <FIG>) configured to heat the heat storage material to the predefined temperature. It is to be noted that the electrical heater is not mandatory. The electrical heater may, e.g., be a grid of electrical coils arranged in the heat storage material <NUM>. The electrical heater may, e.g., be used to initially heat the heat storage material <NUM> to the predefined temperature.

According to some examples of the present disclosure, catalyst material for lowering a reaction temperature of the fluid <NUM> may be arranged within the heat-transfer bed <NUM>. Accordingly, the needed temperature for the reaction of the fluid <NUM> (e.g. oxidation or rection) may be lower such that the fluid purification device <NUM> may operate at lower temperatures. For example, one or more layer of catalyst material may be provided separate from the heat storage material. One or more layer of catalyst material may, e.g., be attached to one or both ends of the heat-transfer bed <NUM> along the (possible) flow directions of the fluid (e.g. near the first opening <NUM> and the second opening <NUM>). Alternatively or additionally, the heat storage material <NUM> in the heat-transfer bed <NUM> (e.g. cordierite) may at least in part be coated with and/or comprise (contain) catalyst material or catalytically active components. Further alternatively or additionally, catalyst material may be admixed to the heat storage material <NUM> in the heat-transfer bed <NUM>. Still further alternatively or additionally, a first part of the heat storage material <NUM> in the heat-transfer bed <NUM> may be coated with and/or comprise (contain) catalyst material or catalytically active components, whereas a second part of the heat storage material <NUM> in the heat-transfer bed <NUM> does not comprise catalyst material and catalytically active components. The first part and the second part of the heat storage material <NUM> may be admixed or be provided as different layers in the heat-transfer bed <NUM>. For example, one or more oxidation catalysts and/or one or more reduction catalysts may be used. However, the present disclosure is not limited thereto. Also other types of catalysts may be used.

The fluid purification device <NUM> may, e.g., purify the fluid <NUM> by Regenerative Thermal Oxidation (RTO). In other examples of the present disclosure, the fluid purification device <NUM> may purify the fluid <NUM> by Regenerative Catalytic Oxidation (RCO). For example, the fluid purification device <NUM> may be configured to purify the fluid <NUM> by flameless RTO or flameless RCO. However, the present disclosure is not limited thereto. Also other reactions of the fluid <NUM> such as a reduction of fluid may be used.

Each of the first plenum <NUM> and the second plenum <NUM> comprises a respective housing <NUM>, <NUM> attached to the heat-transfer bed <NUM> such that the respective volume enclosed by the respective housing <NUM>, <NUM> forms a respective plenum space for alternatingly transporting the fluid <NUM> towards and transporting the reacted fluid <NUM>' away from the heat-transfer bed <NUM>. The first plenum <NUM> and the second plenum <NUM> may alternatingly be coupled to a respective one of a source providing/emitting the fluid <NUM> (e.g. a device such as a machine or a production facility emitting the fluid <NUM>) and a receiver of the reacted fluid <NUM>' (e.g. a chimney for releasing the reacted fluid <NUM>' to the environment or another device or system for further treating the reacted fluid <NUM>') by a coupling system (not illustrated in <FIG>). The coupling system may be part of the fluid purification device <NUM> or be external to the fluid purification device <NUM>. The housing <NUM> of the first plenum <NUM> may according to examples of the present disclosure at least partly be formed of and/or be at least partly covered by a heat-insulating material to minimize heat loses over the housing <NUM> of the first plenum <NUM>. Analogously, the housing <NUM> of the second plenum <NUM> may according to examples of the present disclosure at least partly be formed of and/or be at least partly covered by a heat-insulating material to minimize heat loses over the housing <NUM> of the second plenum <NUM>.

Additionally, the fluid purification device <NUM> comprises a (first) heat blocking element (structure, material, device, means) <NUM> arranged in (inside) the first plenum <NUM>. The heat blocking element <NUM> is spaced apart from the heat-transfer bed <NUM> and is spaced apart from the housing <NUM> of the first plenum <NUM>. The heat blocking element <NUM> extends beyond the first opening <NUM>. A gap <NUM> is formed between a boundary <NUM> of the first opening <NUM> and a surface <NUM> of the heat blocking element <NUM> facing the first opening <NUM>. In other words, the whole first opening <NUM> and a part of the heat insulating wall <NUM> surrounding the first opening <NUM> is covered by the heat blocking element <NUM>. Accordingly, an orthogonal projection of the first opening <NUM> onto a surface <NUM> of the heat blocking element <NUM> facing the first opening <NUM> (the bottom surface of the heat blocking element <NUM> in the example of <FIG>) does not fully cover the surface <NUM> of the heat blocking element <NUM>. The heat blocking element <NUM> is configured to limit heat emission from the heat storage material <NUM> into the first plenum <NUM>. For example, the heat blocking element <NUM> may at least in part be formed of a material storing and/or reflecting at least part of the heat released from the heat-transfer bed <NUM> via the first opening <NUM>. The heat blocking element <NUM> may be formed of any material able to withstand temperatures of up to <NUM>, <NUM> or <NUM> and/or pressures up to two bar. Optionally, the heat blocking element <NUM> may be formed of material able to withstand acidic and/or corrosive media. For example, the heat blocking element <NUM> may at least in part be formed of plastics, carbon, glass fiber, metal (e.g. spring steel) or mixtures, composite and/or laminates thereof.

Due to the presence of the heat blocking element <NUM>, heat released from the heat-transfer bed <NUM> via the first opening <NUM> is at least in part reflected back to the heat-transfer bed <NUM> and/or at least stored near the first opening <NUM> such that it may be used for heating the fluid <NUM> entering the heat-transfer bed <NUM>.

Further, the presence of the heat blocking element <NUM> positively affects the flow distribution of the fluid <NUM>. As illustrated in <FIG>, during a time period in which the first plenum <NUM> is configured to supply the fluid <NUM> to the heat-transfer bed <NUM>, the fluid <NUM> travels through the first plenum <NUM> substantially along a first spatial direction x<NUM>. The first spatial direction x<NUM> is substantially perpendicular to a second spatial direction x<NUM> and a third spatial direction x<NUM>, which denote the main flow directions of the fluid through the through the heat storage material <NUM> (i.e. the direction from the first opening <NUM> to the second opening <NUM>, and vice versa). In the example of <FIG>, the fluid <NUM> substantially travels from the left to the right. The static pressure of the fluid <NUM> in the first plenum <NUM> varies with the speed of the fluid <NUM>. In particular, the static pressure of fluid <NUM> in the first plenum <NUM> increases if the speed of the fluid <NUM> decreases (the dynamic pressure of the fluid <NUM> on the other hand decreases if the speed of the fluid <NUM> decreases). The speed of the fluid <NUM> decreases along the first spatial direction x<NUM> as indicated in <FIG> by the size of the reference signs "V" depicted in the first plenum <NUM>, which decreases from the left to the right.

Due to the heat blocking element <NUM>, the speed of the fluid <NUM> entering the heat-transfer bed <NUM> is highest at the edges of the heat-transfer bed <NUM> along the first spatial direction x<NUM> (i.e. at the right and the left side of the heat-transfer bed <NUM> in the example of <FIG>). Further, the speed of the fluid <NUM> entering the heat-transfer bed <NUM> gets lower towards the middle (center) of the heat-transfer bed <NUM> along the first spatial direction x<NUM>. Lower speed of the fluid <NUM> means lower dynamic pressure and, hence, higher static pressure of the fluid <NUM>. Therefore, the static pressure of the fluid <NUM> entering the heat-transfer bed <NUM> increases from the edges of the heat-transfer bed <NUM> towards the middle of the of the heat-transfer bed <NUM> along the first spatial direction x<NUM>. The static pressure of the fluid <NUM> entering the heat-transfer bed <NUM> is indicated in <FIG> by the size of the reference signs "P" depicted at the first opening <NUM>, which increases from the edges to the middle of the first opening <NUM>. The increase of the static pressure towards the middle of the first opening <NUM> results in a slightly angled flow of the fluid <NUM> through the heat storage material <NUM> of the heat-transfer bed <NUM> to the sides of the heat-transfer bed <NUM>. In other words, some of the fluid <NUM> and also the excess heat generated during the reaction of the fluid <NUM> in the heat-transfer bed <NUM> is transported to the side portions of the heat-transfer bed <NUM> along the first spatial direction x<NUM>. This is indicated in <FIG> by the dotted arrows pointing from the first opening <NUM> to the second opening <NUM>. As can be seen from <FIG>, the dotted arrows are slightly directed towards the lateral edges of the heat-transfer bed <NUM>.

The increasing static pressure of the fluid <NUM> in the first plenum <NUM> in the volume above the heat blocking element <NUM> does, hence, not negatively affect the distribution of the fluid <NUM> in the heat-transfer bed <NUM>.

Optionally, the fluid purification device <NUM> may further comprise another (second) heat blocking element <NUM> arranged in (inside) the second plenum <NUM>. The heat blocking element <NUM> is spaced apart from the heat-transfer bed <NUM> and is spaced apart from the housing <NUM> of the second plenum <NUM>. The heat blocking element <NUM> extends beyond the second opening <NUM>. Another gap <NUM> is formed between a boundary <NUM> of the second opening <NUM> and a surface <NUM> of the heat blocking element <NUM> facing the second opening <NUM>. In other words, the whole second opening <NUM> and a part of the heat insulating wall <NUM> surrounding the second opening <NUM> is covered by the heat blocking element <NUM>. Accordingly, an orthogonal projection of the second opening <NUM> onto a surface <NUM> of the heat blocking element <NUM> facing the second opening <NUM> (the top surface of the heat blocking element <NUM> in the example of <FIG>) does not fully cover the surface <NUM> of the heat blocking element <NUM>. The heat blocking element <NUM> is configured to limit heat emission from the heat storage material <NUM> into the second plenum <NUM>. Like the heat blocking element <NUM>, the heat blocking element <NUM> may at least in part be formed of a material storing and/or reflecting at least part of the heat released from the heat-transfer bed <NUM> via the second opening <NUM>.

Due to the presence of the heat blocking element <NUM>, heat released from the heat-transfer bed <NUM> via the second opening <NUM> is at least in part reflected back to the heat-transfer bed <NUM> and/or at least stored near the second opening <NUM> such that it may be used for heating the fluid <NUM> entering the heat-transfer bed <NUM>.

As indicated in <FIG> by the dotted arrows illustrating the flow distribution of the fluid <NUM> and pointing from the second opening <NUM> to the first opening <NUM>, the heat blocking element <NUM> further positively affects the flow distribution of the fluid <NUM> during a time period in which the second plenum <NUM> is configured to supply the fluid <NUM> to the heat-transfer bed <NUM> analogous to what is described above for the heat blocking element <NUM>.

Further, as indicated in <FIG> by the size of the reference signs "P" depicted at the second opening <NUM>, the heat blocking element <NUM> may cause a corresponding distribution of the static pressure of the reacted fluid <NUM>' leaving the heat-transfer bed <NUM>. As can be seen from <FIG>, the static pressure of the reacted fluid <NUM>' increases from the edges to the middle of the second opening <NUM> along the first spatial direction x<NUM> due to the presence of the heat blocking element <NUM>. This further supports the transport of the fluid <NUM> and the reacted fluid <NUM>' to side portions of the heat-transfer bed <NUM> along the first spatial direction x<NUM>. As indicated in <FIG>, the heat blocking element <NUM> has the same effect on the reacted fluid <NUM>' leaving the heat-transfer bed <NUM> via the second opening <NUM> during the time period in which the second plenum <NUM> is configured to supply the fluid <NUM> to the heat-transfer bed <NUM>.

It is to be noted that the second heat blocking element <NUM> is optional. Improved heat loss and improved flow distribution of the fluid <NUM> compared to conventional approaches may already be achieved when using only the heating blocking element <NUM>.

<FIG> illustrates an exemplary heat (temperature) distribution <NUM> in the heat storage material <NUM> of the heat-transfer bed <NUM> of the exemplary fluid purification device <NUM> having the heat blocking elements <NUM>, <NUM>. The hottest zone is the center <NUM> of the heat-transfer bed <NUM>. Due to heat losses at the thermally insulating wall <NUM>, less heat would be stored at the lateral sides of the heat-transfer bed <NUM>. However, due to the improved flow distribution of the fluid <NUM> caused by at least the heat blocking element <NUM> and optionally also the heat blocking element <NUM>, some of the fluid <NUM> and also the excess heat generated during the reaction of the fluid <NUM> in the heat-transfer bed <NUM> is transported to the lateral side portions <NUM> and <NUM> of the heat-transfer bed <NUM> such that the wall loses may at least in part be compensated. In other words, excess heat is transferred from the center <NUM> of the heat-transfer bed <NUM> to the lateral side portions <NUM> and <NUM> of the heat-transfer bed <NUM> due to the improved flow distribution of the fluid <NUM>.

Accordingly, a more even heat and temperature distribution in the heat-transfer bed <NUM> may be achieved such that the fluid <NUM> is sufficiently heated by the heat-transfer bed <NUM> irrespective of whether the fluid <NUM> flows through the center <NUM> or the lateral side portions <NUM> and <NUM> of the heat-transfer bed <NUM>. Accordingly, no dedicated heating structure for heating the side portions of the heat-transfer bed <NUM> is needed. The total energy loss of the fluid purification device <NUM> may be reduced.

As a reference, <FIG> illustrates a prior art fluid purification device <NUM> not using heat blocking elements. Further illustrated in <FIG> is an exemplary heat distribution <NUM> in the heat storage material of the fluid purification device <NUM>'s heat-transfer bed <NUM>. As can be seen from <FIG>, the heat distribution <NUM> is uneven and causes an uneven temperature distribution in the heat-transfer bed <NUM>. The hottest zone <NUM> is shifted towards the left side of the heat-transfer bed <NUM>. Due to the losses at the thermally insulating wall <NUM>, less heat is stored at the lateral edge portions of the heat-transfer bed <NUM>. In particular, significantly less heat is stored in the right side portion of the heat-transfer bed <NUM>. This may result in insufficient heating of the fluid <NUM> when passing the heat-transfer bed <NUM> and, hence, negatively affect the purification of the fluid <NUM>.

The heat distribution <NUM> illustrated in <FIG> is caused by the significantly different flow distribution of the fluid <NUM> in the fluid purification device <NUM>. This exemplarily illustrated in <FIG> illustrates the flow of the fluid <NUM> through the fluid purification device <NUM> during a time period in which the first plenum <NUM> is configured to supply the fluid <NUM> to the heat-transfer bed <NUM>.

Analogous to the situation illustrated in <FIG>, the fluid <NUM> travels through the first plenum <NUM> substantially along the first spatial direction x<NUM>. The speed of the fluid <NUM> decreases along the first spatial direction x<NUM> as indicated in <FIG> by the size of the reference signs "V" depicted in the first plenum <NUM>, which decreases from the left to the right. Accordingly, the static pressure of fluid <NUM> in the first plenum <NUM> increases along the first spatial direction x<NUM>. The increase of the static pressure of the fluid <NUM> entering the heat-transfer bed <NUM> along the first spatial direction x<NUM> is indicated in <FIG> by the size of the reference signs "P" depicted at the first opening <NUM>, which increases along the first spatial direction x<NUM> (i.e. from the left to the right).

The increasing static pressure along the first spatial direction x<NUM> causes a flow of the fluid <NUM> through the heat storage material of the heat-transfer bed <NUM> towards regions with lower static pressure. This causes an increase of the static pressure of the reacted fluid <NUM>' leaving the heat-transfer bed <NUM> along the first spatial direction x<NUM> is indicated in <FIG> by the size of the reference signs "P" depicted at the second opening <NUM>, which increases along the first spatial direction x<NUM>. In the example of <FIG>, the flow of the fluid <NUM> through the heat storage material of the heat-transfer bed <NUM> is oriented towards the left side of the heat-transfer bed <NUM> such that effectively less heat is stored in the heat storage material at the right side of the heat-transfer bed <NUM>. Accordingly, insufficient compensation of the heat loses through the thermally insulating wall <NUM> occurs, which leads to the heat distribution <NUM> in the heat storage material of the fluid purification device <NUM>'s heat-transfer bed <NUM> as illustrated in <FIG>. This may result in insufficient heating of the fluid <NUM> passing the heat-transfer bed <NUM> at the right side and, hence, negatively affect the purification of the fluid <NUM>.

Further, heat released from the heat-transfer bed <NUM> via the first opening <NUM> may distribute over the entire first plenum and lead to additional heat losses.

The above applies vice versa during a time period in which the second plenum <NUM> is configured to supply the fluid <NUM> to the heat-transfer bed <NUM>.

As described above, using the heating blocking element <NUM> and optionally further the heating blocking element <NUM> may improve heat loss and flow distribution of the fluid <NUM> compared to the fluid purification device <NUM>.

Returning back to <FIG>, it can be seen that the surface <NUM> of the heat blocking element <NUM> extends substantially parallel to the first opening <NUM>. The distance between the heat blocking element <NUM> and the boundary <NUM> / the heat-transfer bed <NUM> is selected such that the gap <NUM> acts as a nozzle for the fluid <NUM> when flowing from the first plenum <NUM> to the heat-transfer bed <NUM>. The gap <NUM> acting as nozzle for the fluid <NUM> may allow to generate the above described flow distribution of the fluid <NUM> in the heat-transfer bed <NUM>.

For defining the gap <NUM> between the surface <NUM> of the heat blocking element <NUM> and the boundary <NUM> of the first opening <NUM>, the heat-transfer bed <NUM> may comprise one or more protrusion <NUM> (e.g. a ledge) formed at the boundary <NUM> of the first opening <NUM>. However, it is to be noted that the one or more protrusion <NUM> are optional and in general not necessary for defining the gap <NUM> between the surface <NUM> of the heat blocking element <NUM> and the boundary <NUM> of the first opening <NUM>.

Analogously, as illustrated in <FIG>, the surface <NUM> of the heat blocking element <NUM> extends substantially parallel to the second opening <NUM>. The distance between the heat blocking element <NUM> and the boundary <NUM> / the heat-transfer bed <NUM> is selected such that the gap <NUM> acts as a nozzle for the fluid <NUM> when flowing from the second plenum <NUM> to the heat-transfer bed <NUM>. The gap <NUM> acting as nozzle for the fluid <NUM> may analogously allow to generate the above described flow distribution of the fluid <NUM> in the heat-transfer bed <NUM>.

For defining the gap <NUM> between the surface <NUM> of the heat blocking element <NUM> and the boundary <NUM> of the second opening <NUM>, the heat-transfer bed <NUM> may comprise one or more other protrusion <NUM> (e.g. a ledge) formed at the boundary <NUM> of the second opening <NUM>. However, it is to be noted that the one or more protrusion <NUM> are optional and in general not necessary for defining the gap <NUM> between the surface <NUM> of the heat blocking element <NUM> and the boundary <NUM> of the second opening <NUM>.

As indicated in <FIG> by the arrows indicating the fluid <NUM> and passing through the heat blocking element <NUM>, a plurality of recesses for passthrough of the fluid <NUM> may optionally be formed in the heat blocking element <NUM>. The plurality of recesses extend from the surface <NUM> of the heat blocking element, which faces the first opening <NUM>, to another opposite surface <NUM> of the heat blocking element <NUM>, which faces the housing <NUM> of the first plenum <NUM>. The plurality of recesses in the heat blocking element <NUM> may support the generation of the above described flow distribution of the fluid <NUM> in the heat-transfer bed <NUM>. According to examples of the present disclosure, a respective size of the plurality of recesses for passthrough of the fluid <NUM> and/or a number of recesses for passthrough per unit area may increase along the first spatial direction x<NUM>. Increasing the respective size of the plurality of recesses for passthrough of the fluid <NUM> and/or the number of recesses for passthrough per unit area along the first spatial direction x<NUM> may allow to lower the effective resistance of the heat blocking element <NUM> for the fluid <NUM> when entering the heat-transfer bed <NUM> and, hence, support the generation of the above described flow distribution of the fluid <NUM> in the heat-transfer bed <NUM>.

The heat blocking element <NUM> may optionally comprise one or more surface structure for controlling a flow direction and/or flow characteristics of the fluid <NUM> locally. In other words, one or more of the surface <NUM> and the surface <NUM> may be structured for controlling the flow direction and/or the flow characteristics of the fluid <NUM> locally in order to support the generation of the above described flow distribution of the fluid <NUM> in the heat-transfer bed <NUM>. For example, one or more guide baffle and/or one or more orifice may be used as surface structures.

As indicated in <FIG> by the arrows indicating the fluid <NUM> and passing through the heat blocking element <NUM>, another plurality of recesses for passthrough of the fluid <NUM> may optionally be formed in the heat blocking element <NUM>. The plurality of recesses extend from the surface <NUM> of the heat blocking element, which faces the second opening <NUM>, to another opposite surface <NUM> of the heat blocking element <NUM>, which faces the housing <NUM> of the second plenum <NUM>. Analogously to what is described above, the plurality of recesses in the heat blocking element <NUM> may support the generation of the above described flow distribution of the fluid <NUM> in the heat-transfer bed <NUM>. Also in the heat blocking element <NUM>, the respective size of the plurality of recesses for passthrough of the fluid <NUM> and/or a number of recesses for passthrough per unit area may increase along the first spatial direction x<NUM>.

As can be seen from <FIG>, the plurality of recesses in the heat blocking element <NUM> further allow the reacted fluid <NUM>' to more easily leave the heat-transfer bed <NUM>. Analogously, the plurality of recesses in the heat blocking element <NUM> further allow the reacted fluid <NUM>' to more easily leave the heat-transfer bed <NUM> as can be seen from <FIG>.

In the example of <FIG>, the heat blocking element <NUM> extends substantially parallel to the first opening <NUM> and the heat blocking element <NUM> extends substantially parallel to the second opening <NUM>. However, the present disclosure is not limited thereto. <FIG> illustrates another fluid purification device <NUM> with tilted heat blocking elements. <FIG> illustrates the fluid purification device <NUM> during a time period in which the first plenum <NUM> is configured to supply the fluid <NUM> to the heat-transfer bed <NUM> and the second plenum <NUM> is configured to drain the reacted fluid <NUM>' from the heat-transfer bed <NUM>.

In the example of <FIG>, the surface <NUM> of the heat blocking element <NUM>, which faces the first opening <NUM>, is tilted with respect to the first opening <NUM>. Accordingly, a distance between the surface <NUM> of the heat blocking element <NUM> and the first opening <NUM> increases along the first spatial direction x<NUM>. Analogously, a distance between the opposite surface <NUM> of the heat blocking element <NUM> and a wall <NUM> of the first plenum's housing <NUM> decreases along the first spatial direction x<NUM>. The first opening <NUM> and the wall <NUM> of the first plenum's housing <NUM> are arranged on opposite sides of the heat blocking element <NUM>.

Analogously, the surface <NUM> of the heat blocking element <NUM>, which faces the second opening <NUM>, may be tilted with respect to the second opening <NUM>. Accordingly, a distance between the surface <NUM> of the heat blocking element <NUM> and the second opening <NUM> increases along the first spatial direction x<NUM>. Analogously, a distance between the opposite surface <NUM> of the heat blocking element <NUM> and a wall <NUM> of the second plenum's housing <NUM> decreases along the first spatial direction x<NUM>. The second opening <NUM> and the wall <NUM> of the second plenum's housing <NUM> are arranged on opposite sides of the heat blocking element <NUM>.

As described above for the parallel heat blocking elements <NUM> and <NUM>, also the tilted heat blocking elements <NUM> and <NUM> in the example of <FIG> may allow to improve heat loss and flow distribution of the fluid <NUM>. The tilt angles of the heat blocking elements <NUM> and <NUM> with respect to the respective one of the first opening <NUM> and the second opening <NUM> may be identical to each other as illustrated in <FIG>. However, the present disclosure is not limited thereto. In other examples, different tilt angles may be used for the heat blocking elements <NUM> and <NUM>.

In the above examples, the heat blocking elements <NUM> and <NUM> do not comprise any moving parts. However, the present disclosure is not limited thereto. In the following, examples will be described with reference to <FIG>, <FIG> and <FIG>, in which the heat blocking element <NUM> comprises at least one respective movable element for adjusting the gap to the boundary of the respective opening <NUM>. The respective fluid purification device is illustrated in each of <FIG>, <FIG> and <FIG> during a time period in which the first plenum <NUM> is configured to supply the fluid <NUM> to the heat-transfer bed <NUM> and the second plenum <NUM> is configured to drain the reacted fluid <NUM>' from the heat-transfer bed <NUM>.

In the fluid purification device <NUM> illustrated in <FIG>, the heat blocking element <NUM> comprises two movable elements <NUM> and <NUM> for adjusting the gap <NUM> between the boundary <NUM> of the first opening <NUM> and at least part of the surface <NUM> of the heat blocking element <NUM>. The two movable elements <NUM> and <NUM> are edge portions of the heat blocking element <NUM> coupled to a central portion <NUM> of the heat blocking element <NUM>. The two movable elements <NUM> and <NUM> are movable with respect the central portion <NUM> of the heat blocking element <NUM>.

Analogously, the heat blocking element <NUM> comprises two movable elements <NUM> and <NUM> for adjusting the gap <NUM> between the boundary <NUM> of the second opening <NUM> and at least part of the surface <NUM> of the heat blocking element <NUM>. The two movable elements <NUM> and <NUM> are edge portions of the heat blocking element <NUM> coupled to a central portion <NUM> of the heat blocking element <NUM>. The two movable elements <NUM> and <NUM> are movable with respect the central portion <NUM> of the heat blocking element <NUM>.

In the fluid purification device <NUM> illustrated in <FIG>, the heat blocking element <NUM> comprises one movable element <NUM> for adjusting the gap <NUM> between the boundary <NUM> of the first opening <NUM> and a part of the surface <NUM> of the heat blocking element <NUM>. The movable element <NUM> is coupled to a static element <NUM> of the heat blocking element <NUM>. The movable element <NUM> is movable with respect the static element <NUM> of the heat blocking element <NUM>.

Analogously, the heat blocking element <NUM> comprises one movable element <NUM> for adjusting the gap <NUM> between the boundary <NUM> of the second opening <NUM> and a part of the surface <NUM> of the heat blocking element <NUM>. The movable element <NUM> is coupled to a static element <NUM> of the heat blocking element <NUM>. The movable element <NUM> is movable with respect the static element <NUM> of the heat blocking element <NUM>.

In the fluid purification device <NUM> illustrated in <FIG>, the heat blocking element <NUM> comprises two movable elements <NUM> and <NUM> for adjusting the gap <NUM> between the boundary <NUM> of the first opening <NUM> and the surface <NUM> of the heat blocking element <NUM>. The two movable elements <NUM> and <NUM> are coupled to and moveable with respect to each other.

Analogously, the heat blocking element <NUM> comprises two movable elements <NUM> and <NUM> for adjusting the gap <NUM> between the boundary <NUM> of the second opening <NUM> and the surface <NUM> of the heat blocking element <NUM>. The two movable elements <NUM> and <NUM> are coupled to and moveable with respect to each other.

The heat blocking element <NUM> in each of the fluid purification devices <NUM>, <NUM> and <NUM> illustrated <FIG>, <FIG> and <FIG> comprises at least one movable element for adjusting the gap <NUM> between the boundary <NUM> of the first opening <NUM> and at least part of the surface <NUM> of the heat blocking element <NUM>. Analogously, the heat blocking element <NUM> in each of the fluid purification device <NUM>, <NUM> and <NUM> comprises at least one movable element for adjusting the gap <NUM> between the boundary <NUM> of the second opening <NUM> and at least part of the surface <NUM> of the heat blocking element <NUM>.

For moving the at least one movable element of the heat blocking element <NUM>, each of the fluid purification devices <NUM>, <NUM> and <NUM> may further comprise at least one actuator (not illustrated) coupled to the at least one movable element of the heat blocking element <NUM>. The at least one actuator is configured to adjust a respective positioning and/or orientation of the at least one movable element of the heat blocking element <NUM> relative to the boundary <NUM> of the first opening <NUM>.

For moving the at least one movable element of the heat blocking element <NUM>, each of the fluid purification devices <NUM>, <NUM> and <NUM> may further comprise at least one further actuator (not illustrated) coupled to the at least one movable element of the heat blocking element <NUM>. The at least one actuator is configured to adjust a respective positioning and/or orientation of the at least one movable element of the heat blocking element <NUM> relative to the boundary <NUM> of the second opening <NUM>.

By varying the distance of the at least one movable element of the heat blocking element <NUM> relative to the boundary <NUM> of the first opening <NUM>, the variation of the static pressure at the first opening <NUM> may be adjusted (controlled) along the first spatial direction x<NUM> in order to support the generation of the above described flow distribution of the fluid <NUM> in the heat-transfer bed <NUM>. Analogously, the variation of the static pressure at the second opening <NUM> may be adjusted (controlled) along the first spatial direction x<NUM> by varying the distance of the at least one movable element of the heat blocking element <NUM> relative to the boundary <NUM> of the second opening <NUM>.

The at least one actuator for varying the distance of the at least one movable element of the heat blocking element <NUM> relative to the boundary <NUM> of the first opening <NUM> may, e.g., comprise a hydraulic system and/or a combination of an electric motor and a drive system for moving the at least one movable element of the heat blocking element <NUM>. The heat blocking element <NUM> may be implemented analogously.

The at least one actuator for varying the distance of the at least one movable element of the heat blocking element <NUM> relative to the boundary <NUM> of the first opening <NUM> may, e.g., be configured to adjust the distance of the at least one movable element of the heat blocking element <NUM> relative to the boundary <NUM> of the first opening <NUM> based on a temperature and/or a pressure and/or a differential pressure in the first plenum <NUM> as these quantities affect the variation of the static pressure at the first opening <NUM>. Alternatively or additionally, the at least one actuator for varying the distance of the at least one movable element of the heat blocking element <NUM> relative to the boundary <NUM> of the first opening <NUM> may, e.g., be configured to adjust the distance of the at least one movable element of the heat blocking element <NUM> relative to the boundary <NUM> of the first opening <NUM> time based and/or event based. For example, the distance may be varied in a time period directly before or after changing the overall fluid direction inside the first plenum <NUM> and the second plenum130, or in case of exceptional events such as concentration peaks or downs in the fluid (e.g. a gas stream) entering the fluid purification device. Analogously, the at least one actuator for varying the distance of the at least one movable element of the heat blocking element <NUM> relative to the boundary <NUM> of the second opening <NUM> may, e.g., be configured to adjust the distance of the at least one movable element of the heat blocking element <NUM> relative to the boundary <NUM> of the second opening <NUM> based on a temperature and/or a pressure and/or a differential pressure in the second plenum <NUM> (as these quantities affect the variation of the static pressure at the second opening <NUM>) and/or time based and/or event based.

For example, the at least one actuator for varying the distance of the at least one movable element of the heat blocking element <NUM> relative to the boundary <NUM> of the first opening <NUM> and the at least one actuator for varying the distance of the at least one movable element of the heat blocking element <NUM> relative to the boundary <NUM> of the second opening <NUM> may comprise or be coupled to one or more control circuitry for controlling the operation of the respective at least one actuator based on the temperature and/or the pressure and/or the differential pressure in the respective plenum and/or time based and/or event based. According to examples, the respective fluid purification device may comprise one or more sensor coupled to the one or more control circuitry and configured to measure the temperature and/or the pressure and/or the differential pressure in the respective plenum.

For example, the one or more control circuitry may be a single dedicated processor, a single shared processor, or a plurality of individual processors, some of which or all of which may be shared, a digital signal processor (DSP) hardware, an application specific integrated circuit (ASIC), or a field programmable gate array (FPGA). The one or more control circuitry may optionally be coupled to, e.g., read only memory (ROM) for storing software (e.g. storing a program for controlling the respective at least one actuator), random access memory (RAM) and/or non-volatile memory.

<FIG> illustrates another exemplary fluid purification device <NUM> using bendable heat blocking elements. The fluid purification device <NUM> is illustrated in <FIG> during a time period in which the first plenum <NUM> is configured to supply the fluid <NUM> to the heat-transfer bed <NUM> and the second plenum <NUM> is configured to drain the reacted fluid <NUM>' from the heat-transfer bed <NUM>.

The heat blocking element <NUM> is bendable. In particular, the heat blocking element <NUM> comprises one or more bimetal structure configured to bend the heat blocking element based on a temperature in the first plenum <NUM> for adjusting the gap <NUM> between the boundary <NUM> of the first opening <NUM> and at least part of the surface <NUM> of the heat blocking element <NUM>. For example, the whole heat blocking element <NUM> may be formed as a bimetal structure for obtaining the temperature sensitive bending. In other examples, one or more bimetal structure may be formed in or on the heat blocking element <NUM> for obtaining the temperature sensitive bending.

By varying the distance of the at least one movable element of the heat blocking element <NUM> relative to the boundary <NUM> of the first opening <NUM>, the variation of the static pressure at the first opening <NUM> may be adjusted (controlled) along the first spatial direction x<NUM> in order to support the generation of the above described flow distribution of the fluid <NUM> in the heat-transfer bed <NUM>.

An alternative bending configuration is illustrated in <FIG> for the heat blocking element <NUM>. The heat blocking element <NUM> is bendable for adjusting the gap <NUM> between the boundary <NUM> of the second opening <NUM> and at least part of the surface <NUM> of the heat blocking element <NUM>. For example, the heat blocking element <NUM> may at least in part be formed of a bendable/flexible material (e.g. the heat blocking element <NUM> may at least in part be formed of plastics, carbon, glass fiber, metal (e.g. spring steel) or mixtures, composite, laminates thereof analogous to what is described above for the heat blocking element <NUM>)).

For bending the heat blocking element <NUM>, the fluid purification device further comprises at least one actuator <NUM> configured to exert a force on the heat blocking element <NUM> for bending the heat blocking element <NUM>. In the example of <FIG>, one end of the heat blocking element <NUM> is fixed and the at least one actuator <NUM> exerts the force for bending the heat blocking element <NUM> on the other end of the heat blocking element <NUM>. In other words, the at least one actuator <NUM> exerts a lateral force on the heat blocking element <NUM>.

However, the present disclosure is not limited thereto. For example, the at least one actuator <NUM> may exert the force on the heat blocking element <NUM> along a spatial direction, which is substantially perpendicular to the surface <NUM> of the heat blocking element <NUM> when the heat blocking element <NUM> is not bent (e.g. along the third spatial direction x<NUM>). In this example, both ends of the heat blocking element <NUM> may be fixed.

The at least one actuator <NUM> may, e.g., be a stamp. However, it is to be noted that the present disclosure is not limited thereto. In general, any means that can be driven by, e.g., a hydraulic system or a (e.g. electric) motor to exert a force on the heat blocking element <NUM> may be used.

It is to be noted that in alternative examples, also the heat blocking element <NUM> may be based on a bimetal structure. In other words, analogously to the heat blocking element <NUM> described above, the heat blocking element <NUM> may comprise one or more bimetal structure configured to bend the heat blocking element <NUM> based on a temperature in the second plenum <NUM> for adjusting the gap <NUM> between the boundary <NUM> of the second opening <NUM> and at least part of the surface <NUM> of the heat blocking element <NUM>.

Similarly, it is to be noted that in alternative examples, also the heat blocking element <NUM> may be bent by at least one actuator. In other words, analogously to the heat blocking element <NUM> described above, the heat blocking element <NUM> may be bendable for adjusting the gap <NUM> between the boundary <NUM> of the first opening <NUM> and at least part of the surface <NUM> of the heat blocking element <NUM>. Accordingly, the fluid purification device may further comprise at least one actuator configured to exert a force on the heat blocking element <NUM> for bending the heat blocking element <NUM>.

Analogously to what is described above with respect to <FIG>, the respective at least one actuator for exerting the respective force on the respective one of the heat blocking element <NUM> and the heat blocking element <NUM> may be configured to exert the respective force based one a temperature and/or a pressure and/or a differential pressure in the respective one of first plenum <NUM> and the second plenum <NUM> as these quantities affect the variation of the static pressure at the respective one of the first opening <NUM> and the second opening <NUM>. Alternatively or additionally, the respective at least one actuator for exerting the respective force on the respective one of the heat blocking element <NUM> and the heat blocking element <NUM> may be configured to exert the respective force time based and/or event based. For example, the respective at least one actuator may change the force exerted on the respective one of the heat blocking element <NUM> and the heat blocking element <NUM> during a time period directly before or after changing the overall fluid direction inside the first plenum <NUM> and the second plenum130, or in case of exceptional events such as concentration peaks or downs in the fluid (e.g. a gas stream) entering the fluid purification device. The respective at least one actuator may comprise or be coupled to one or more control circuitry for controlling the operation of the respective at least one actuator based on the temperature and/or the pressure and/or the differential pressure in the respective plenum and/or time based and/or event based - analogously to what is described above with respect to <FIG>.

In the above examples, the heat blocking elements <NUM> and <NUM> are plate-shaped. However, the present disclosure is not limited thereto. In general, the heat blocking elements <NUM> and <NUM> may exhibit any suitable shape. <FIG> illustrates another exemplary fluid purification device <NUM> using wedge-shaped heat blocking elements <NUM> and <NUM>. The fluid purification device <NUM> is illustrated in <FIG> during a time period in which the first plenum <NUM> is configured to supply the fluid <NUM> to the heat-transfer bed <NUM> and the second plenum <NUM> is configured to drain the reacted fluid <NUM>' from the heat-transfer bed <NUM>.

The surface <NUM> of the heat blocking element <NUM> extends substantially parallel to the first opening <NUM> such that the gap <NUM> formed between the boundary <NUM> of the first opening <NUM> and the surface <NUM> of the heat blocking element <NUM> acts as a nozzle for the fluid <NUM> when flowing from the first plenum <NUM> to the heat-transfer bed <NUM>.

The opposite surface <NUM> of the heat blocking element <NUM> faces the wall <NUM> of the first plenum's housing <NUM>. Due to the wedge-shape of the heat blocking element <NUM>, a distance between the surface <NUM> and the other surface <NUM> of the heat blocking element increases along the first spatial direction x<NUM>, and a distance between the surface <NUM> of the heat blocking element <NUM> and the wall <NUM> of the first plenum's housing <NUM> decreases along the first spatial direction x<NUM>.

As the distance between the surface <NUM> of the heat blocking element <NUM> and the wall <NUM> of the first plenum's housing <NUM> decreases along the first spatial direction x<NUM>, the volume of the first plenum <NUM> for the fluid <NUM> decrease along the first spatial direction x<NUM>. The decrease in volume along the first spatial direction x<NUM> allows to compensate for the decrease in speed of the fluid <NUM> along the first spatial direction x<NUM>. By decreasing the volume of the first plenum <NUM> for the fluid <NUM> along the first spatial direction x<NUM>, the variation of the static pressure at the first opening <NUM> may be adjusted along the first spatial direction x<NUM> in order to support the generation of the above described flow distribution of the fluid <NUM> in the heat-transfer bed <NUM>.

The other heat-blocking element <NUM> may be shaped analogously as illustrated in <FIG>. That is, the surface <NUM> of the heat blocking element <NUM> extends substantially parallel to the second opening <NUM> such that the gap <NUM> formed between the boundary <NUM> of the second opening <NUM> and the surface <NUM> of the heat blocking element <NUM> acts as a nozzle for the fluid <NUM>. The opposite surface <NUM> of the heat blocking element <NUM> faces the wall <NUM> of the second plenum's housing <NUM>. Due to the wedge-shape of the heat blocking element <NUM>, a distance between the surface <NUM> and the other surface <NUM> of the heat blocking element <NUM> increases along the first spatial direction x<NUM>, and a distance between the surface <NUM> of the heat blocking element <NUM> and the wall <NUM> of the second plenum's housing <NUM> decreases along the first spatial direction x<NUM>.

In the example of <FIG>, the heat blocking elements <NUM> and <NUM> exhibit a wedge shape. However, it is to be noted that the present disclosure is not limited thereto. In general any shape causing that the distance between the surface <NUM> and the other surface <NUM> of the heat blocking element <NUM> increases along the first spatial direction x<NUM>, and that the distance between the surface <NUM> of the heat blocking element <NUM> and the wall <NUM> of the first plenum's housing <NUM> decreases along the first spatial direction x<NUM> may be used for the heat blocking element <NUM>. The same holds true in analogous manner for the heat blocking element <NUM>. For example, instead of a linear increase of the distance between the surface <NUM> and the other surface <NUM> of the heat blocking element <NUM> as illustrated in <FIG>, a nonlinear increase of the distance between the surface <NUM> and the other surface <NUM> of the heat blocking element <NUM> may be used.

In the above examples, the first plenum <NUM> and the second plenum <NUM> extend lengthwise along the first spatial direction x<NUM> such that the fluid <NUM> travels along the along the first spatial direction x<NUM> while the respective one of the first plenum <NUM> and the second plenum <NUM> is configured to supply the fluid <NUM> to the heat-transfer bed <NUM>. However, the present disclosure is not limited thereto. According to examples of the present disclosure, the first plenum <NUM> and the second plenum <NUM> may extend lengthwise along different spatial directions. In particular, the first plenum <NUM> and the second plenum <NUM> may extend lengthwise along anti-parallel spatial directions. This is exemplarily illustrated in <FIG> illustrates another exemplary fluid purification device <NUM> during a time period in which the first plenum <NUM> is configured to supply the fluid <NUM> to the heat-transfer bed <NUM> and the second plenum <NUM> is configured to drain the reacted fluid <NUM>' from the heat-transfer bed <NUM>.

The example of <FIG> is based on the example described above with respect to <FIG> and <FIG>, contrary to the above example, the second plenum <NUM> extends along a fourth spatial direction x<NUM>, which is anti-parallel to the first spatial direction x<NUM>. Accordingly, unlike in the above examples, the reacted fluid <NUM>' does not travel through the second plenum <NUM> along the fourth spatial direction x<NUM> during a time period in which the second plenum <NUM> is configured to drain the reacted fluid <NUM>' from the heat-transfer bed <NUM>. Instead, the reacted fluid <NUM>' travels through the second plenum <NUM> along the first spatial direction x<NUM>. Analogously, during a time period in which the second plenum <NUM> is configured to supply the fluid <NUM> to the heat-transfer bed <NUM> and the first plenum <NUM> is configured to drain the reacted fluid <NUM>' from the heat-transfer bed <NUM>, the fluid <NUM> does not travel through the second plenum <NUM> along the first spatial direction x<NUM> but along the anti-parallel fourth spatial direction x<NUM>.

It is to be noted that according to examples of the present disclosure, the first plenum <NUM> and the second plenum <NUM> may also in the above described examples extend lengthwise along different spatial directions. In particular, the first plenum <NUM> and the second plenum <NUM> may also in the above described examples extend lengthwise along anti-parallel spatial directions similar to the example of <FIG>. The positioning and/or orientation of the heat blocking element <NUM> in the second plenum <NUM> may be adjusted/changed accordingly (e.g. the positioning and/or orientation of the heat blocking element <NUM> may be with respect to the fourth spatial direction x<NUM> instead of the first spatial direction x<NUM> as described above).

Further, it is to be noted that although not explicitly described, the heat blocking element <NUM> may also in the examples of <FIG> optionally comprise a plurality of recesses for passthrough of the fluid <NUM> and/or one or more surface structure for controlling a flow direction and/or flow characteristics of the fluid <NUM> locally analogously to what is described with respect to the example of <FIG> and <FIG>. The same holds true for the heat blocking element <NUM>.

The examples described with respect to <FIG> may each comprise at least one actuator coupled to the heat blocking element for moving one or more movable object or exerting a bending force on the respective heat blocking element <NUM> or <NUM>. However, the present disclosure is not limited thereto. In general, in any of the above examples, the respective fluid purification device may comprise at least one actuator coupled to the heat blocking element <NUM> and configured to adjust a positioning and/or orientation of the heat blocking element <NUM>'s surface <NUM> with respect to the first opening <NUM>. For example, distance of the heat blocking element <NUM>'s surface <NUM> with respect to the first opening <NUM> may be adjusted to tune the nozzle-effect of the gap <NUM>. Alternatively or additionally, a tilt angle of the heat blocking element <NUM>'s surface <NUM> with respect to the first opening <NUM> may be adjusted. For example, the tilt angle of the heat blocking element <NUM>'s surface <NUM> with respect to the first opening <NUM> may be changed such that the orientation of the heat blocking element <NUM>'s surface <NUM> illustrated in <FIG> is changed to the orientation of the heat blocking element <NUM>'s surface <NUM> illustrated in <FIG>.

The same holds true in analogous manner for the heat blocking element <NUM>. That is, in any of the above examples, the respective fluid purification device may comprise at least one actuator coupled to the heat blocking element <NUM> and configured to adjust a positioning and/or orientation of the heat blocking element <NUM>'s surface <NUM> with respect to the second opening <NUM>.

Analogously to what is described above with respect to <FIG>, the respective at least one actuator for adjusting the positioning and/or orientation of the respective one of the heat blocking element <NUM> and the heat blocking element <NUM> may be configured to adjust the respective positioning and/or orientation based on a temperature and/or a pressure and/or a differential pressure in the respective one of the first plenum <NUM> and the second plenum <NUM> as these quantities affect the variation of the static pressure at the respective one of the first opening <NUM> and the second opening <NUM>. Alternatively or additionally, the respective at least one actuator for adjusting the positioning and/or orientation of the respective one of the heat blocking element <NUM> and the heat blocking element <NUM> may be configured to adjust the respective positioning and/or orientation time based and/or event based. For example, the respective at least one actuator may change the respective positioning and/or orientation of the heat blocking element <NUM> and the heat blocking element <NUM> during a time period directly before or after changing the overall fluid direction inside the first plenum <NUM> and the second plenum <NUM>, or in case of exceptional events such as concentration peaks or downs in the fluid (e.g. a gas stream) entering the fluid purification device. The respective at least one actuator may comprise or be coupled to one or more control circuitry for controlling the operation of the respective at least one actuator based on the temperature and/or the pressure and/or the differential pressure in the respective plenum and/or time based and/or event based - analogously to what is described above with respect to <FIG>.

For further illustrating the proposed architecture for fluid purification, <FIG> illustrates a flowchart of a method <NUM> for operating a fluid purification device according to the present disclosure. The method <NUM> comprises supplying <NUM> fluid to the heat-transfer bed alternatingly through the first plenum and the second plenum such that the fluid heats up and reacts while flowing through the heat storage material. Additionally, the method <NUM> comprises, during a time period in which one of the first plenum and the second plenum supplies the fluid to the heat-transfer bed, draining <NUM> the reacted fluid from the heat-transfer bed through the other one of the first plenum and the second plenum.

Similar to what is described above, the method <NUM> may enable improved purification of the fluid compared to conventional approaches. In particular, the heat blocking element in the first plenum may allow to reduce heat loses at the first opening of the heat-transfer bed. Furthermore, the heat blocking element in the first plenum may allow for an improved flow distribution of the fluid over the heat-transfer bed such that a more even temperature distribution in the heat-transfer bed may be achieved.

More details and aspects of the method <NUM> are explained in connection with the proposed technique or one or more example described above (e.g. <FIG> and <FIG>). The method <NUM> may comprise one or more additional optional feature corresponding to one or more aspect of the proposed technique or one or more example described above.

Claim 1:
A fluid purification device, comprising:
a heat-transfer bed (<NUM>) filled with heat storage material (<NUM>);
a first plenum (<NUM>) attached to a first opening (<NUM>) of the heat-transfer bed (<NUM>);
a second plenum (<NUM>) attached to a second opening (<NUM>) of the heat-transfer bed (<NUM>),
wherein the first opening (<NUM>) and the second opening (<NUM>) are arranged on opposite sides of the heat-transfer bed (<NUM>); and
wherein the first plenum (<NUM>) and the second plenum (<NUM>) are configured to alternatingly supply fluid (<NUM>) to the heat-transfer bed (<NUM>) such that the fluid (<NUM>) heats up and reacts while flowing through the heat storage material (<NUM>), and
wherein, during a time period in which one of the first plenum (<NUM>) and the second plenum (<NUM>) is configured to supply the fluid (<NUM>) to the heat-transfer bed (<NUM>), the other one of the first plenum (<NUM>) and the second plenum (<NUM>) is configured to drain the reacted fluid from the heat-transfer bed (<NUM>),
characterised by a heat blocking element (<NUM>) arranged in the first plenum (<NUM>), wherein the heat blocking element (<NUM>) is spaced apart from the heat-transfer bed (<NUM>) and is spaced apart from a housing (<NUM>) of the first plenum (<NUM>), wherein the heat blocking element (<NUM>) extends beyond the first opening (<NUM>) and is configured to limit heat emission from the heat storage material (<NUM>) into the first plenum (<NUM>).