DE102015205547A1 - Shaped body for tempering a fluid and constructed with such moldings heat exchanger - Google Patents

Abstract

A shaped body for tempering a fluid, which can be used, for example, to form a heat bed (24) of a regenerator (14), comprises a block (27) of a thermally conductive material passing through a base (XY) and perpendicular to the base extending height is defined, wherein the block (27) in cross-section parallel to its base (XY) has a plurality of cells (28) and these cells (28) each have a cross-sectional shape parallel to the base (XY) of the block in the form of a regular polygon to have. In the block (27) is further formed a plurality of channels (30, 32, 38) which are substantially parallel to each other and to the height direction (Z) of the block, each of the channels (30, 32, 38) in a cell (28) is provided such that between the channels (30, 32, 38) in adjacent cells (28) an inner wall (34) is present.

Description

TECHNICAL FIELD OF THE INVENTION

The present invention relates to a shaped body for tempering a fluid and a heat exchanger having at least one heat bed, which has at least one such shaped body. The present invention further relates to a thermoreactor, in particular for the regenerative thermal oxidation of combustible substances in an exhaust air or exhaust gas stream having at least one such heat exchanger as a regenerator.

TECHNICAL BACKGROUND

Thermoreactors, in particular those in plants for regenerative thermal oxidation (RTO) of combustible substances in a waste air or exhaust gas flow, typically have a combustion chamber acted upon by a gas stream to be thermally reacted and at least two regenerators, for example below the combustion chamber. Preferably, one of the regenerators in a certain operating state of the thermoreactor with a (first) gas flow is applied, which is supplied to the combustion chamber, while the other regenerator is acted upon with a (second) gas stream, which exits from the combustion chamber. Usually, the first gas stream receives from the flow-through regenerator a certain amount of heat energy, while the second gas stream in turn emits heat energy to the associated regenerator. For temporary storage of thermal energy, in addition to heat-storing fillings (eg balls, caliper bodies, etc.), heat generators with ceramic bodies, for example or alternatively, are used in regenerators. These are characterized by a predictable and homogeneous pressure difference at a certain flow through the respective heat bed, since in the channels of the blocks usually a laminar flow of the passed through the regenerator fluid (gas or liquid) is formed.

The thermal efficiency and service life of the regenerators are important parameters for the efficient use of such regenerators. However, the thermal efficiency and the service life are influenced by the formation of deposits within the regenerators with subsequent blockage of individual flow channels or entire blocks in the heated beds (so-called "blocking"). This "blocking" arises in particular by precipitation of solids from the fluid passed through, with certain solids settle on the channel walls and accumulate there. For example, in the purification of siloxane-containing flashings, the failure of Si oxides on the channel walls occurs.

The blocking of the regenerators has the consequence that the heat beds of affected RTO plants have to be freed from the deposits at regular intervals or the affected moldings of the heat beds must be replaced. For this maintenance work, the RTO system must be shut down and cooled down before the heatsinks can be cleaned or replaced. It usually takes 2 to 3 working days for the RTO system to become operational again. During this time, the production area connected to the RTO plant will generally not be able to fully operate, so that the service life, ie. H. The time it takes to lock the heated beds, a regenerator of an RTO system, can be a decisive factor for the efficiency and economy of the system.

SUMMARY OF THE INVENTION

It is an object of the invention to provide an improved heat exchanger which avoids or at least reduces the above described disadvantages of the prior art.

In particular, a heat exchanger with a good thermal efficiency and a good resistance to blocking of its flow channels should be created.

Another object of the invention is to provide a shaped body for tempering a fluid flow, which achieves a favorable ratio between the lowest possible mass of the shaped body on the one hand and the greatest possible dynamic heat capacity on the other.

This object is achieved by the teaching of the independent claims. Particularly preferred embodiments and further developments of the invention are specified in the dependent claims.

According to a first aspect of the invention, a shaped body for tempering a fluid comprises a block of a thermally conductive material which is defined by a base surface and a height perpendicular to the base surface. The block has in cross-section parallel to its base a plurality of cells, these cells each having a cross-sectional shape parallel to the base of the block in the form of a regular polygon. Also formed in the block are a plurality of channels that are substantially parallel to each other and to the height direction of the block, each of these channels being provided in a cell such that there is an interior wall between the channels in adjacent cells.

The cross-sectional shape of the cells in the form of regular polygons has the advantage that the cells can be arranged side by side with a small distance from each other, for example to build a thermal bed of a regenerator. In addition, the channels in the cells can be safely separated from one another in this cross-sectional shape of the cells.

The block of the shaped body is formed of a thermally conductive material. The thermally conductive material preferably has a thermal conductivity of at least about 1.5 W / mK, preferably at least about 2.0 W / mK or more. In addition, the heat-conductive material preferably has a low coefficient of thermal expansion of at most about 1 × 10 ^-4 K ^-1 , preferably at most about 1 × 10 ^-5 K ^-1 , 8 × 10 ^-6 K ^-1 or less (each at 800 ° C) C). Further, the heat conductive material preferably has a high specific heat capacity of at least about 500 J / kgK, preferably at least about 800 J / kgK or more. Moreover, a preferred thermally conductive material has a softening temperature of at least about 1,000 ° C, more preferably at least about 1,200 ° C, even more preferably at least about 1,400 ° C. The thermally conductive material for the molded article is preferably selected from ceramics, brick, clay, metals, precious metals, silica, carbides, graphite or the like high-temperature-stable materials. Particularly preferred are ceramics with a proportion of more than 50% of silica and / or alumina.

The cross-sectional shape of the cells parallel to the base of the block is preferably in the shape of a triangle, square, pentagon, hexagon or octagon, with the hexagonal cross-sectional shape being particularly preferred.

The block according to the invention comprises a plurality of cells having a cross-sectional shape in the form of a regular polygon. The cells are preferably unit cells, i. H. essentially identically designed and dimensioned cells. In addition, the block - in particular depending on the base surface shape of the block and cross-sectional shape of these cells - but also have other cells with different cross-sectional shapes. Such cells with other cross-sectional shapes may preferably be present in the edge region of the block.

The channels are preferably positioned substantially centrally in the individual cells.

The block of the shaped body is preferably formed in one piece. Accordingly, the cells of the block are not formed by separate components, but are defined geometrically within the block.

In a preferred embodiment of the invention, the channels each have a cross-sectional shape parallel to the base of the block in the form of a circle. The circular cross-section of the channels is particularly efficient in terms of heat transfer between the fluid passed through the channels and the molded body, so that this embodiment can also improve the thermal efficiency of an overall system (for example a suitably equipped thermal reactor).

In another preferred embodiment of the invention, the channels each have a cross-sectional shape parallel to the base of the block in the form of a regular polygon. The cross-sectional shape of the channels is preferably in the shape of a triangle, square, pentagon, hexagon or octagon, with the hexagonal cross-sectional shape being particularly preferred. Preferably, the channels each have a cross-sectional shape parallel to the base surface of the block in the form of a polygon corresponding to the regular polygon of the cells, so that a wall thickness of the inner walls between adjacent channels is substantially constant.

In a further preferred embodiment of the invention, a hydraulic diameter of a channel is at least about 2.30 mm and / or at most about 5.00 mm. The hydraulic diameter of the channels is preferably selected from the values 2.34 mm, 2.61 mm, 2.81 mm, 2.90 mm, 4.85 mm and 4.87 mm. In the case of channels with a circular cross-sectional shape corresponds to the hydraulic Diameter substantially the circle diameter of the cross-sectional shape. In the case of other channel geometries, the hydraulic diameter substantially corresponds to the diameter of a circle inside the cross-sectional shape (in-circle diameter).

In a further preferred embodiment of the invention, a minimum wall thickness of an inner wall between adjacent channels is at least about 0.20 mm and / or at most about 1.00 mm. Preferably, the wall thickness is configured in a value range between 0.25 mm and 0.89 mm. Particularly preferred individual values for a substantially uniform wall thickness of all channels are 0.23 mm, 0.25 mm, 0.48 mm, 0.56 mm and 0.81 mm. It has been found that in such a (preferably uniform) definition of the wall thickness of all channels in a molded body according to the invention an optimum can be achieved between the lowest possible mass of the block on the one hand and the greatest possible heat capacity on the other. This is especially true when using a material having a thermal conductivity of between about 1.5 W / mK and 8.0 W / mK and a (mean) flow velocity of a gaseous fluid flow passing through the channels between 1 m / s and 6.5 m / s ,

In a further preferred embodiment of the invention, a quotient of a hydraulic diameter of a channel to a minimum wall thickness of the inner wall between adjacent channels is at most about 6.0, preferably at most about 5.5. Specifically, said quotient ranges between 4.1 and 5.9 using a material having a thermal conductivity between about 1.5 W / mK and 8.0 W / mK and an (average) flow velocity of a gaseous fluid flow passing the channels 1 m / s and 6.5 m / s. The viscosity of the gaseous fluid flow can be between 20 μPa s and 40 μPa s. It has been found that in such a (preferably uniform) determination of the ratio between the hydraulic diameter of the channels and wall thickness of the channels in a molded body according to the invention an optimum can be achieved between the lowest possible mass of the block on the one hand and the greatest possible heat capacity.

In a further preferred embodiment of the invention, a hydraulic flow cross-sectional area of a channel is at least about 50% and / or at most about 65% with respect to a cross-sectional area of the cell. Such an interpretation also contributes to an optimization of the ratio between the smallest possible mass of the block and the largest possible heat absorption capacity. Specifically, said value is between 51% and 63% using a material having a thermal conductivity between about 1.5 W / mK and 8.0 W / mK and a (mean) flow velocity of a gaseous fluid flow passing the channels between 1 m / s and 6.5 m / s. The viscosity of the gaseous fluid flow can be between 15 μPa s and 40 μPa s.

In another preferred embodiment of the invention, an open cross-sectional area of a channel is at least about 50% and / or at most about 75% with respect to a cross-sectional area of the cell.

In a further preferred embodiment of the invention, a Nusselt number of a laminar flow channel is at least about 3.5, preferably at least about 4.0, and / or at most about 4.5. The Nusselt number is defined as a dimensionless quantity as a product of the hydraulic diameter with the quotient of the heat transfer coefficient to the coefficient of thermal conductivity. Such a design choice is particularly preferred with simultaneous execution of the block of a ceramic material with a proportion of more than 50% aluminum and / or silicon oxides. Such a design choice is particularly preferred in the simultaneous execution of the block of a material for producing a block according to the invention, which has a thermal conductivity between about 1.5 W / mK and 8 W / mK. Optionally, it can be provided that a correspondingly shaped molding is passed by a gaseous fluid flow with a (mean) flow velocity between 1 m / s and 6.5 m / s. The viscosity of the gaseous fluid flow can be between 15 μPa s and 40 μPa s.

In yet another preferred embodiment of the invention, the walls delimiting the channels are provided with a protective layer, for example in the form of a protective layer of nanoparticles. For the realization of a protective layer according to the invention, particles of silicon oxide, titanium dioxide, aluminum oxide, iron oxide, zinc oxide, silicon carbide, iron carbide, tungsten carbide, titanium nitride, boron nitride and boron carbide are proposed, the largest dimension of each being less than 100 nm. Such a "nano-protective layer" is produced According to the invention, a nano-scale rough surface on the inner walls of the channels, so that form microscopic vortexes on the channel surface. A deposition of (from the fluid flowing through the shaped body through or for other reasons carried in the fluid) solid particles is prevented or slowed down. In this way, a "blocking" the channels are effectively prevented. In preferred embodiments, the protective layer has a surface roughness Ra of less than 25 μm, in particular less than 10 μm, particularly preferably less than 2.5 μm. Preferably, the protective layer may be formed as a hydrophobic layer. In other applications, however, it may also be advantageous to make the protective layer hydrophilic.

In a further preferred embodiment of the invention, a structure length of the cross-sectional shape of a channel is limited to about 3.5 mm, preferably to about 3.0 mm. The structure length of the cross-sectional shape of a channel is understood to be an edge length of the relevant n-edge in the case of an n-cornered channel. It has been found that a tendency to form deposits of solids precipitated from gaseous fluid flow at temperatures between 400 ° C and 1100 ° C, greatly increases from a "critical structure length". Concretely, for a channel of hexagonal cross-sectional shape, the critical structure length with respect to deposition of silicon oxides is about 2.82 mm when the channel is traversed with a siloxane-containing exhaust gas at a speed between 1 m / s and 6.5 m / s. The viscosity of the exhaust gas can be between 15 μPa s and 40 μPa s. By limiting the structure length of the channel cross section, it is generally possible to reduce deposition of solids (precipitated from the fluid flow at relatively high temperatures or entrained in the fluid flow for other reasons) on a channel wall. For gaseous fluids with a nitrogen content of more than 60% by volume, therefore, a limitation of the structure length of the cross-sectional shape of an n-cornered channel to 3.5 mm is proposed.

In yet another preferred embodiment of the invention, the cross-sectional shape of the channels has at least one concave (i.e., inwardly curved) portion. Preferably, the cross-sectional shape of the channels alternately has a plurality of concave portions and a plurality of convex portions. This special structure of the cross-sectional area of the channels can preferably prevent or slow down the deposition of solid particles (precipitated from the fluid flowing through the shaped body or otherwise entrained in the fluid) and thus blockage of the channels.

According to a further aspect of the invention, a heat exchanger has at least one heat-bed, which has at least one shaped body of the invention described above.

In one embodiment, a heat exchanger according to the invention has at least one heat bed, which has at least one shaped body for tempering a fluid, wherein the shaped body has a block of a thermally conductive material which is defined by a base surface and a height perpendicular to the base surface, wherein the block in cross-section parallel to its base a plurality of cells, the cells each having a cross-sectional shape parallel to the base of the block in the form of a regular polygon, wherein in the block a plurality of channels is formed, which are substantially parallel to each other and the height direction of the Blocks, and wherein each of the channels is provided in a cell such that between the channels in adjacent cells, an inner wall is present.

In a preferred embodiment of the invention, the heat bed has a plurality of shaped bodies, which are arranged parallel to the base surface of the molded bodies next to one another and preferably without spacing from one another. In this way, it is possible to divide a fluid flow to be passed through to an arbitrarily expandable number of shaped bodies and thus to set the volume flow per shaped body and the corresponding flow rate. The preferred flow velocity is between 1 m / s and 6.5 m / s.

In a further preferred embodiment of the invention, the heat exchanger has at least two heat beds, which are arranged one above the other in the height direction of the molded bodies. The channels of the superimposed moldings are preferably substantially coaxially or parallel to each other, preferably have the same cross-sectional shapes and / or preferably have the same dimensions. By superimposing heat beds, the heat absorption capacity of the heat exchanger can be adjusted. It has been found that in the case of a number of 5 to 9 layers of similar heat beds, an overall height of the heat exchanger of 1.2 m to 3.5 m and a corresponding total length of through-flow channels can be achieved. Such a design choice is particularly preferred with simultaneous execution of a plurality of heat exchanger blocks of a ceramic material with a proportion of more than 50% aluminum and / or silicon oxides. Such a design choice is particularly preferred with simultaneous execution of the heat exchanger blocks of a material for producing a block according to the invention, which has a thermal conductivity between about 1.5 W / mK and 8 W / mK. Optionally it can be provided that a suitably designed heat exchanger of a gaseous fluid flow with a (mean) flow rate between 1 m / s and 6.5 m / s is happening. The viscosity of the gaseous fluid flow can be between 15 μPa s and 40 μPa s.

In a further preferred embodiment of the invention, a height of the heat bed in the height direction of the shaped body is at least about 20 cm, preferably at least about 25 cm, and / or at most about 50 cm, preferably at most about 40 cm.

In a still further preferred embodiment of the invention, a height of the heat exchanger in the height direction of the shaped body is at least about 100 cm, preferably at least about 150 cm, and / or at most about 300 cm, preferably at most about 200 cm.

According to another aspect of the invention, a thermoreactor comprises a combustion chamber and a regenerator, the regenerator being configured as a heat exchanger of the invention described above. The thermoreactor according to the invention can be used in particular in plants for the regenerative thermal oxidation of combustible substances in a waste air or exhaust gas flow in an advantageous manner. The channels of the moldings are preferably open towards the combustion chamber, so that the fluid can flow through the regenerators into the combustion chamber or out of the combustion chamber.

In a preferred embodiment of the invention, a thermal reactor, in particular for the regenerative thermal oxidation of combustible substances in a waste air or exhaust gas flow, a combustion chamber and a regenerator, wherein the regenerator has at least one heat bed with at least one shaped body for tempering a fluid, wherein the Shaped body has a block of a thermally conductive material, which is defined by a base and a height perpendicular to the base height, wherein the block in cross-section parallel to its base a plurality of cells, wherein the cells each have a cross-sectional shape parallel to the base surface of the block in Form a regular polygon, wherein in the block a plurality of channels are formed, which are substantially parallel to each other and to the height direction of the block, and wherein each of the channels is provided in a cell such that between the channels in benac Cells have an inner wall.

• – mittlere Strömungsgeschwindigkeit zwischen 1 m/s und 6,5 m/s,
• – Viskosität zwischen 15 μPa·s und 40 μPa·s
• – Temperatur zwischen 400°C und 1100°C
• – Stickstoffanteil größer als 60 Vol.-%.

According to a further aspect of the invention, a thermoreactor has a combustion chamber and a regenerator, wherein the regenerator contains one or more shaped bodies according to the invention, which are in particular composed to a heat bed and flowed through by a particular substantially gaseous fluid flow, wherein the fluid flow of one or more having the following features:

• Mean flow velocity between 1 m / s and 6.5 m / s,
• Viscosity between 15 μPa s and 40 μPa s
• - Temperature between 400 ° C and 1100 ° C
• - Nitrogen content greater than 60 vol .-%.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other relevant features of the solutions according to the invention will become apparent from the following description of various concrete embodiments, for which the above-mentioned embodiments are also applied vice versa, with reference to the accompanying drawings. In it show, mostly schematically:

1 a representation of a thermal reactor according to a first embodiment;

2 a representation of a thermal reactor according to a second embodiment;

2A a representation of a thermal reactor according to a variant of the second embodiment;

2 B a representation of a thermal reactor according to another variant of the second embodiment;

3 a top view of a heat bed for a thermal reactor of 1 or 2 ;

4 an enlarged partial plan view of a shaped body of a heat bed of 3 according to a first embodiment;

5 an enlarged partial plan view of a shaped body of a heat bed of 3 according to a second embodiment;

6 an enlarged partial plan view of a shaped body of a heat bed of 3 according to a third embodiment;

7 an enlarged plan view of a cell of a shaped body of a heat bed of 3 according to a fourth embodiment; and

8th a sectional view of a regenerator with multiple layers of thermal beds for a thermal reactor of 1 or 2 ,

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

1 shows a thermoreactor 10 , which can be used, for example, in a plant for regenerative thermal oxidation (RTO) of a combustible substances, in particular volatile organic constituents (VOC) containing exhaust air or exhaust gas stream, according to a first embodiment.

The thermoreactor 10 has a combustion chamber 12 and two below the combustion chamber 12 arranged regenerators 14 on. In the embodiment shown, the thermoreactor 10 two regenerators 14 on each of which an atrium 16 assigned. In other embodiments, however, can also be three, four or more regenerators 14 be provided. In the combustion chamber 12 a burner (not shown) projects beyond the liquid or gaseous fuel and optionally also combustion air into the combustion chamber 12 be initiated. The burner is used to generate a flame in the combustion chamber, which in turn allows ignition and combustion of the pollutants contained in the raw gas to be purified. The temperature in the combustion chamber 12 may be up to about 1,250 ° C during operation - depending on the energy content of the flammable substances contained in the raw gas.

The antechambers 16 the regenerators 14 are each with a raw gas supply 18 and with a clean gas discharge 20 connected. The about the raw gas feed 18 in an antechamber 16 Raw gas introduced is in the respective regenerator 14 warmed up before it enters the combustion chamber 12 is directed. After a thermal conversion of the raw gas in the combustion chamber 12 hot clean gas is created, which in the other regenerator 14 is cooled before passing over the other antechamber 16 and the clean gas discharge 20 is derived in an exhaust air system. In a modified embodiment, the cooled clean gas stream may be fed to further heat exchange and / or purification stages before the clean gas is discharged into the environment or for further use.

In the embodiment of 1 become the thermoreactor 10 and its regenerators 14 by switching the control valves 22a . 22b in the raw gas feed 18 and the clean gas discharge 29 alternately flows through in opposite predetermined flow directions in certain predetermined time intervals. For more detailed operation of such a thermoreactor is exemplified at the point EP 1 312 861 B1 directed.

2 shows a thermoreactor 10 according to a second embodiment, which can also be used, for example, in a plant for regenerative thermal oxidation (RTO) of a combustible substances-containing waste air or exhaust gas flow.

The thermoreactor 10 from 2 is different from the thermoreactor 10 from 1 through a different kind of flow control. As in 2 shown, are the raw gas supply 18 and the clean gas discharge 20 each with a common rotary valve 23 connected, which in turn with the antechambers 16 both regenerators 14 connected is. By a rotation of the rotary valve 23 become the thermoreactor 10 and its regenerators 14 also flows through in opposite directions alternately in certain predeterminable time intervals.

2A shows a variant of the embodiment of the invention 2 , In this embodiment, the thermoreactor 10 a common regenerator construction 14 on, which is fluidically separated into two areas, so that the same operation as in the embodiment of 2 results.

2 B shows a further variant of the embodiment of the invention 2 , In this embodiment, the thermoreactor 10 ' with his regenerators 14 rotatably designed and via a common distribution valve 23 ' with the raw gas supply 18 and the clean gas discharge 20 connected. Such a configuration is especially for small thermoreactors 10 ' be provided.

In further variants of the invention, the embodiments of 2A and 2 B also with the embodiment of 1 be combined.

For embodiments with a rotating thermoreactor 10 ' For the clean gas flow, preferably an average flow velocity between 0.6 m / s and 2.5 m / s and a burner-side temperature between 700 ° C and 900 ° C and an outlet-side temperature between 40 ° and 150 ° C are set. The viscosity of the clean gas flow can be between 15 μPa s and 35 μPa s.

For embodiments with a fixed or stationary thermoreactor 10 For the clean gas flow, preferably an average flow velocity between 1 m / s and 6.5 m / s and a burner-side temperature between 800 ° C and 1100 ° C and an outlet-side temperature between 60 ° and 250 ° C are set. The viscosity of the clean gas flow can be between 20 μPa · s and 40 μPa · s. The values mentioned can acquire particular significance in connection with the geometry of certain shaped bodies described below.

As in 1 and 2 indicated, point the regenerators 14 of the thermoreactor 10 in each case several superimposed heat beds 24 on. These warmth beds 24 are each made of a variety of moldings 26 composed, which are arranged perpendicular to the stacking direction of the heat beds (= height direction Z of the heat beds and the molded body) substantially without a distance from each other next to each other, as in 3 shown. Preferably, the shaped bodies 26 a warm bed 24 designed and dimensioned essentially identical to one another.

The preferred structure of the moldings 26 for the warming beds 24 will be referred to hereinafter with reference to several embodiments 4 to 7 explained in more detail.

The molded body 26 according to the in 4 illustrated first embodiment has a block 27 made of a ceramic material. Preferably, a hard ceramic with a proportion of more than 50% aluminum and / or silicon oxides can be used. Also preferred are ceramic materials having a thermal conductivity of between about 1.5 W / mK and 8 W / mK (preferably, for example, about 2.1 W / mK), a low thermal expansion coefficient of at most about ^{1.10 -5} K ^-1 (preferably, for example, about 6.5 · 10 ^-6 K ^-1 ) at 800 ° C, a high specific heat capacity of at least about 800 J / kgK (preferably, for example, about 910 J / kgK), and a high softening temperature of at least about 1,000 ° C for the block 27 used. Optionally, other high temperature stable materials can be used for the block 27 be used.

The block 27 For example, it has a substantially rectangular or square footprint parallel to the XY plane. As in 4 illustrates is the block 27 parallel to this base XY into a plurality of unit cells 28 divided, which have a square cross-sectional shape in this embodiment. The unit cells 28 border directly on each other.

In each of the unit cells 28 is a channel 30 . 32 educated. The channels 30 . 32 extend substantially parallel to each other and substantially parallel to a height direction Z (perpendicular to the plane of 4 ) of the block 27 , The channels preferably have a square cross-sectional shape (channels 30 ) or a circular cross-sectional shape (channels 32 ) and are each substantially centered in the cells 28 arranged.

As in 4 recognizable, is between the channels 30 . 32 adjacent cells 28 each an inner wall 34 available. Besides, the block is 27 from an exterior wall 36 enclosed.

The channels 30 . 32 each define a hydraulic diameter dh, that of the square channels 30 one side of the square and the circular channels 32 corresponds to a diameter of the circle, and a hydraulic flow cross-sectional area Ah. In the case of circular channels 32 For example, the hydraulic flow sectional area Ah coincides with the open flow area Ao in the case of the square channels 30 the hydraulic flow cross-sectional area Ah is smaller than the open flow cross-sectional area Ao of the channels.

The interior walls 34 between the channels 30 . 32 adjacent cells 28 have a minimum wall thickness t. The wall thickness t 'of the outer wall 36 is greater than the minimum wall thickness t of the inner wall.

5 shows a shaped body 26 according to a second embodiment. The molded body 26 of the second embodiment differs from that of the first embodiment by the cross-sectional shapes of the unit cells 28 and the channels 30 ,

In the second embodiment of 5 have the unit cells 28 a hexagonal cross-sectional shape. Likewise, the channels have 30 a hexagonal cross-sectional shape. In the edge region of the molding 26 Optionally, cells can also be used 28 ' and channels 30 ' be present with other cross-sectional shapes.

6 shows a shaped body 26 according to a third embodiment. The molded body 26 from 6 differs from that of the second embodiment by the cross-sectional shape of the channels 32 ,

In the third embodiment of 6 have the unit cells 28 a hexagonal cross-sectional shape. The channels 32 on the other hand have a circular cross-sectional shape. In the edge region of the molding 26 can also cells here optionally 28 ' and channels 32 ' be present with different cross-sectional shapes.

The following overview compares some parameters of the moldings 26 according to the various embodiments with each other. Ie in mm t in mm DH / t Ah Ao Q1 3.02 0.71 4.25 50.3% 64.0% Q2 2.41 0.56 4.30 49.5% 63.0% H1 4.85 0.89 5.45 60.8% 67.0% H2 2.90 0.56 5.18 62.0% 68.3% Y1 4.87 0.81 6.01 63.3% 63.35 Y2 2.81 0.48 5.85 62.6% 62.6% Y3 2.34 0.56 4.18 56.0% 56.0%

Q1 and Q2 are shaped bodies 26 according to the first embodiment of 4 with square channels 30 , H1 and H2 are shaped bodies 26 according to the second embodiment of 5 , and Y1 and Y2 and Y3 are molded bodies 26 according to the third embodiment of 6 , each in different variants (in particular with regard to the dimensioning of the channels).

From theoretical model calculations and practical experiments, it has been found that a circular cross-sectional shape (Y1, Y2, Y3) is beneficial for the thermal efficiency of the molded article, and thin inner walls and large hydraulic diameters (Q2, H2, Y2, Y3) are against Blocking the channels are beneficial. In addition, the cross-sectional areas of the cells 28 in the form of regular polygons (eg square, hexagon) advantageous for the compact and substantially gapless arrangement of the cells 28 ,

The dimensionless Nusselt number Nu for a laminar flow, defined as the product of the hydraulic diameter Dh with the quotient of the heat transfer coefficient k1 to the coefficient of thermal conductivity k2, d. H. For example, for the molded bodies Q1 and Q2 having channels having a square cross-sectional shape, Nu = Dh · k1 / k2 is about Nu = 3.61, for the molded bodies H1 and H2 having channels having a hexagonal cross-sectional shape, for example, about Nu = 4.00, and for the moldings Y1, Y2 and Y3 having channels with a circular cross-sectional shape, for example, about Nu = 4.36.

7 shows a cell 28 a shaped body 26 according to a fourth embodiment. The molded body 26 from 7 differs from that of the second and third embodiments by the cross-sectional shape of the channels.

The channel 38 the cell 28 of the molding 26 This embodiment has a star-like cross-sectional shape. The star-like cross-sectional shape is characterized in that alternately several convex (ie curved outward) sections 38a and a plurality of concave (ie, inwardly curved) sections 38b are provided. These convex and concave sections 28a . 38b are starting from a circular basic shape 38 ' achievable by sinusoidal and / or cosinusoidal oscillations. The number N of vibrations is preferably N = 6 (as in the example of FIG 7 ), but may also be N = 8 or N = 12, for example. The sections with constant curvature sign (ie convex, concave or rectilinear) of the curve are preferably less than about 2.85 mm. In addition to the in 7 shown cross-sectional shape of the channel 38 Numerous other variants are conceivable, in particular with star-like or flower-like cross-sectional shapes.

Referring to 8th is now the structure of a regenerator 14 with several layers of a-g of heated beds 24 described in more detail.

The regenerator 14 is a reactor housing 40 of the thermoreactor 10 below the combustion chamber 12 arranged. The lower base of the regenerator 14 forms a grate 42 (eg of metal or precious metal), on which optionally an expanded metal or expanded metal mesh 44 lies.

On the grate 42 and the expanded metal 44 are the several layers a-g of warming beds 24 arranged. Every heat bed 24 is made of a variety of moldings 26 composed. The warming beds 24 or shaped body 26 the layers a-f each have a height h of, for example, about 30 cm, while the heat bed 24 or the shaped body 26 The optional top layer will have a height h of, for example, only about 15 inches, allowing for the regenerator 14 Overall, a height H of about 195 cm results in this embodiment. Between the warming beds 24 and the reactor housing 40 is optional also a so-called caliper body 46 provided from heat-storing bulk material.

In this embodiment, the thermal bed is 24 the lowest layer a, for example, from 23 × 29 moldings 26 of the above type H2, are the heat beds 24 the layers b-e, for example, from 23 × 29 moldings 26 of the above type Y2 is the thermal bed 24 the position f, for example, 21 × 27 moldings 26 of the above type Y2, and is the thermal bed 24 the uppermost layer g, for example, from 21 × 27 moldings 26 of the above type H2. In another embodiment, the moldings 26 the heat chains of the outer layers a and g, for example, of the above type H2 or Y2, and are the heat chains of the inner layers b-f, for example, of the above type Y2 in the star-shaped modification according to the fourth embodiment of FIG 7 ,

Of course, there are also numerous other embodiments for the layers a-g of the heat beds 24 , including other numbers of heated beds and other numbers of moldings per heat bed possible. Typical variants of regenerators 14 contain by way of example the following numbers of moldings 26 in the X or Y direction and on layers of heat beds 24 : Number of moldings X Y documents 8th 13 5-7 10 13 5-7 14 13 5-7 16 13 5-7 15 16 5-7 17 16 5-7 15 23 5-7 19 23 5-7 22 23 5-7 29 23 5-7 29 26 5-7

LIST OF REFERENCE NUMBERS

10

thermoreactor

10 '

thermoreactor

12

combustion chamber

14

regenerator

16

antechamber

18

Rohgaszuführung

20

Clean gas outlet

22a

control valve

22b

control valve

23

rotary valve

23 '

distribution valve

24

Warmer

26

moldings

27

block

28

Cell, unit cell

28 '

modified cell, border cell

30

Channel (polygonal cross-sectional shape)

32

Channel (circular cross-sectional shape)

34

inner wall

36

outer wall

38

Channel (star-shaped cross-sectional shape)

38 '

circular basic form of 38

38a

convex section

38b

concave section

40

reactor housing

42

grating

44

expanded metal

46

saddles

Ah

hydraulic flow cross-sectional area

Ao

open flow cross-sectional area

ie

hydraulic diameter

H

Height of 24 respectively. 26

H

Height of 14

t

minimum wall thickness of the inner wall

t '

Wall thickness of the outer wall

X-Y

Floor space

Z

height direction

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• EP 1312861 B1 [0050]

Claims (20)

Shaped body for tempering a fluid, comprising: a block ( 27 ) of a thermally conductive material defined by a base (XY) and a height perpendicular to the base, the block ( 27 ) in cross-section parallel to its base (XY) a plurality of cells ( 28 ), the cells ( 28 ) each have a cross-sectional shape parallel to the base surface (XY) of the block in the form of a regular polygon, in the block ( 27 ) a plurality of channels ( 30 . 32 . 38 ) which are substantially parallel to one another and to the height direction (Z) of the block, and each of the channels ( 30 . 32 . 38 ) in a cell ( 28 ) is provided such that between the channels ( 30 . 32 ) in adjacent cells ( 28 ) an inner wall ( 34 ) is available. Shaped body according to claim 1, wherein the channels ( 32 ) each have a cross-sectional shape parallel to the base surface (XY) of the block ( 27 ) in the form of a circle. Shaped body according to claim 1, wherein the channels ( 30 ) each have a cross-sectional shape parallel to the base surface (XY) of the block ( 27 ) in the form of a regular polygon. Shaped body according to claim 3, wherein the channels ( 30 ) each have a cross-sectional shape parallel to the base surface (XY) of the block ( 27 ) in the form of a regular polygon of cells ( 28 ) have corresponding polygons, so that a wall thickness of the inner walls ( 34 ) between adjacent channels ( 30 ) is substantially constant. Shaped body according to one of the preceding claims, wherein a hydraulic diameter (Dh) of a channel ( 30 . 32 . 38 ) is at least about 2.30 mm or at most about 5.00 mm, and is preferably selected from the values 2.34 mm, 2.61 mm, 2.81 mm, 2.90 mm, 4.85 mm and 4, 87 mm. Shaped body according to one of the preceding claims, wherein a minimum wall thickness (t) of the inner wall ( 34 ) between adjacent channels ( 30 . 32 . 38 ) is at least about 0.20 mm or at most about 1.00 mm, and is preferably selected in a value range between 0.25 mm and 0.89 mm. Shaped body according to one of the preceding claims, wherein a quotient (Dh / t) of a hydraulic diameter (Dh) of a channel ( 30 . 32 . 38 ) to a minimum wall thickness (t) of the inner wall ( 34 ) between adjacent channels ( 30 . 32 ) is at most about 6.0, preferably at most about 5.5. Shaped body according to one of the preceding claims, wherein a hydraulic flow cross-sectional area (Ah) of a channel ( 30 . 32 . 38 ) at least about 50% or at most about 65% with respect to a cross-sectional area of the cell ( 28 ) is. Shaped body according to one of the preceding claims, wherein an open cross-sectional area (Ao) of a channel (Ao) 30 . 32 . 38 ) at least about 50% or at most about 75% with respect to a cross-sectional area of the cell ( 28 ) is. Shaped body according to one of the preceding claims, in which a Nusselt number (Nu) of a channel ( 30 . 32 . 38 ) is at least about 3.5, preferably at least about 4.0, or at most about 4.5. Shaped body according to one of the preceding claims, in which the channels ( 30 . 32 . 38 ) bounding walls ( 34 . 36 ) are provided with a protective layer. Shaped body according to one of the preceding claims, wherein a structure length of the cross-sectional shape of the channel ( 30 . 32 . 38 ) is limited to about 3.5 mm, preferably about 3.0 mm. Shaped body according to one of the preceding claims, in which the cross-sectional shape of the channels ( 38 ) at least one concave section ( 38b ) having. Heat exchanger ( 14 ), comprising at least one thermal bed ( 24 ), the at least one shaped body ( 26 ) according to one of claims 1 to 13. Heat exchanger according to claim 14, in which the heat bed ( 24 ) several moldings ( 26 ), which are arranged parallel to the base surface (XY) of the shaped bodies next to one another, preferably without spacing from one another. Heat exchanger according to claim 14 or 15, which comprises at least two heat sinks ( 24 ), which in the height direction (Z) of the shaped body ( 26 ) are arranged one above the other. Heat exchanger according to one of claims 14 to 16, wherein a height (h) of the heat bed ( 24 ) in the height direction (Z) of the shaped bodies ( 26 ) is at least about 20 cm, preferably at least about 25 cm, or at most about 50 cm, preferably at most about 40 cm. Heat exchanger according to one of claims 14 to 17, wherein a height (H) of the heat exchanger ( 14 ) in the height direction (Z) of the shaped bodies ( 26 ) is at least about 100 cm, preferably at least about 150 cm, or at most about 300 cm, preferably at most about 200 cm. Thermoreactor ( 10 ), in particular for the regenerative thermal oxidation of combustible substances in an exhaust air or exhaust gas stream, comprising a combustion chamber ( 12 ) and a regenerator ( 14 ), wherein the regenerator ( 14 ) is configured as a heat exchanger according to one of claims 14 to 18. Thermoreactor ( 10 ), in particular for the regenerative thermal oxidation of combustible substances in an exhaust air or exhaust gas stream, comprising a combustion chamber ( 12 ) and a regenerator ( 14 ), wherein the regenerator ( 14 ) one or more moldings ( 26 ) according to one of claims 1 to 13, in particular to a heat bed ( 24 ) are flowed through and flowed through by a particular substantially gaseous fluid flow, the fluid flow having one or more of the following characteristics: average flow velocity between 1 m / s and 6.5 m / s, viscosity between 15 μPa s and 40 μPa · s, - temperature between 400 ° C and 1100 ° C, - nitrogen content greater than 60 vol .-%.

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