Abrasion protection grid for protecting steamcracker quench coolers

Abstract

An abrasion protection element (110) is proposed, comprising - a plurality of flow guiding elements (112), wherein each of the flow guiding elements (112) comprises a core of Oxide Ceramic Matrix Composite, OCMC, and a protective ceramic cover covering of the core; - at least one support structure (114) configured for mounting the flow guiding elements (112), wherein the support structure (114) comprises a layered structure comprising at least one layer of OCMC and at least one layer of ceramic.

Description

[0001] Abrasion protection grid for protecting steamcracker quench coolers

[0002] Technical Field

[0003] The invention relates to an abrasion protection element, a quench cooler configured for cooling at least one gas stream and a steam cracker.

[0004] Background art

[0005] Product gas of a steam cracker, at the outlet of coils may be at temperatures of approximately 800 °C and may be heavily loaded with particles, also denoted as soot. For cooling of the gas stream a so-called quench cooler, is usually used. Due to high velocities, the soot has the same effect to the apparatus as sandblasting.

[0006] It is known that the quench cooler has to be protected against wear, e.g. from US 4,142,578. Various forms of abrasion grids and deflection devices were proposed used such as described in GB 2056653, DE 3 908 277, EP 0 377 089, WO 2021 / 171223, US 2009 / 0242178. Moreover, protective layers are known such as from EP1674815.

[0007] However, despite these achievements, due to the harsh environment, in particular high temperature, high flow velocity and particle load, the protection is heavily stressed and the known techniques can suffer from deformation, wear and abrasion. Moreover, the typically used materials have catalytically active surfaces, promoting formation of heavy coke plaque, which blocks the passage of the gas stream and constraints thermal expansion. This can impair the function and causes damage of such a protection grid, finally leading to frequent and unplanned shutdowns of the cracker for replacement. Thus, there is a need for a device for reliably protecting the quench cooler, in particular for extending its lifetime.

[0008] Problem to be solved

[0009] It is therefore desirable to provide an abrasion protection element, a quench cooler configured for cooling at least one gas stream and a steam cracker which at least partially address the above-mentioned technical challenges. Specifically, increasing the lifetime of the quench cooler, in particular an increased runtime of the steam cracker, due to a decreased number of shutdowns, is desirable.

[0010] Summary

[0011] This problem is addressed by an abrasion protection element, a quench cooler configured for cooling at least one gas stream and a steam cracker with the features of the independent claims. Advantageous embodiments which might be realized in an isolated fashion or in any arbitrary combinations are listed in the dependent claims as well as throughout the specification. As used in the following, the terms “have”, “comprise” or “include” or any arbitrary grammatical variations thereof are used in a non-exclusive way. Thus, these terms may both refer to a situation in which, besides the feature introduced by these terms, no further features are present in the entity described in this context and to a situation in which one or more further features are present. As an example, the expressions “A has B”, “A comprises B” and “A includes B” may both refer to a situation in which, besides B, no other element is present in A (i.e. a situation in which A solely and exclusively consists of B) and to a situation in which, besides B, one or more further elements are present in entity A, such as element C, elements C and D or even further elements.

[0012] Further, it shall be noted that the terms “at least one”, “one or more” or similar expressions indicating that a feature or element may be present once or more than once typically will be used only once when introducing the respective feature or element. In the following, in most cases, when referring to the respective feature or element, the expressions “at least one” or “one or more” will not be repeated, non-withstanding the fact that the respective feature or element may be present once or more than once.

[0013] Further, as used in the following, the terms "preferably", "more preferably", "particularly", "more particularly", "specifically", "more specifically" or similar terms are used in conjunction with optional features, without restricting alternative possibilities. Thus, features introduced by these terms are optional features and are not intended to restrict the scope of the claims in any way. The invention may, as the skilled person will recognize, be performed by using alternative features. Similarly, features introduced by "in an embodiment of the invention" or similar expressions are intended to be optional features, without any restriction regarding alternative embodiments of the invention, without any restrictions regarding the scope of the invention and without any restriction regarding the possibility of combining the features introduced in such way with other optional or non-optional features of the invention.

[0014] In a first aspect, an abrasion protection element is disclosed.

[0015] The abrasion protection element comprises a plurality of flow guiding elements, wherein each of the flow guiding elements comprises a core of Oxide Ceramic Matrix Composite, OCMC, and a protective ceramic cover covering of the core; at least one support structure configured for mounting the flow guiding elements, wherein the support structure comprises a layered structure comprising at least one layer of OCMC and at least one layer of ceramic.

[0016] The term “abrasion” as used herein is a broad term and is to be given its ordinary and customary meaning to a person of ordinary skill in the art and is not to be limited to a special or customized meaning. The term specifically may refer, without limitation, to one or more of wearing, grinding, or rubbing away by friction. For example, without an abrasion protection element, particles of a fluid flow, e.g. of product gas of a steam cracker, impinge on an inlet of a quench cooler such that the inlet is subject to abrasion. Material degradation of the inlet and shutdowns of the quench cooler, e.g. for repair, would be the result. The term “abrasion protection” as used herein is a broad term and is to be given its ordinary and customary meaning to a person of ordinary skill in the art and is not to be limited to a special or customized meaning. The term specifically may refer, without limitation, to a property characterizing the ability for one or more of shielding, covering, securing from abrasion.

[0017] The term “abrasion protection element” as used herein is a broad term and is to be given its ordinary and customary meaning to a person of ordinary skill in the art and is not to be limited to a special or customized meaning. The term specifically may refer, without limitation, to at least one device configured for one or more of preventing, reducing or dampening influence of abrasion. The abrasion protection element may be configured for covering and / or shielding at least one further element, in particular from one or more of exposure, damage, or destruction due to abrasion. The abrasion protection element may be designed as a protective cover of the further element. For example, the abrasion protection element may be configured for protecting the inlet of the quench cooler. The abrasion protection element may be designed as an impingement element. The abrasion protection element may be configured for influencing one or more of a direction, a distribution, an amount of an impinging fluid flow, e.g. by scattering, reflecting and the like.

[0018] The abrasion protection element comprises a plurality of flow guiding elements. The flow guiding elements may define a flow grid. The flow grid may have a plurality passages configured such that the fluid flow can flow through. The flow grid may comprise a plurality of layers, wherein each layer comprises a plurality of flow guiding elements. The abrasion protection element may have a plurality of flow guiding elements such as from 2 to 100, preferably from 2 to 50, more preferably from 2 to 30. A layer of flow guiding elements may have 1 to 25, preferably 2 to 15 flow guiding elements.

[0019] The flow grid may define a coordinate system. A main flow direction of the fluid flow may be along or parallel to a negative y-axis. The flow guiding elements may be arranged essentially along an x-axis at defined relative distances between neighboring flow guiding elements. A length of the flow guiding elements may be aligned essentially along or parallel to a z-axis.

[0020] For example, a length of the flow guiding element may be from 100 mm to 2000 mm, preferably from 200 mm to 1500 mm. A width of a projection of the flow guiding element in main flow direction may be from 5 mm to 100 mm, preferably from 10 mm to 70 mm, more preferably from 15 mm to 50 mm. A width of a projection of the flow guiding element perpendicular to the main flow direction may be from 5 mm to 100 mm, preferably from 10 mm to 70 mm, more preferably from 15 mm to 50 mm. A width of a stagnation area on the side of the flow guiding element facing the flow may be from 0 to 70 mm, preferably from 0 to 50 mm. A width of a stagnation area on the side of the flow guiding element facing away from the flow may be from 0 to 10 mm, preferably from 0 to 5 mm.

[0021] For example, the flow grid may comprise two layers, i.e. a first layer and a second layer, of flow guiding element stacked behind each other in the main flow direction (y-axis). The flow guiding elements of the second layer may be arranged with an x-offset with respect to the x-positions of the flow guiding elements of the first layer. The flow guiding elements of the first and second layers may be arranged such that a complete cross-section of the abrasion protection element, impinged by the fluid flow, is covered.

[0022] The abrasion protection element may have a cross sectional area, e.g. from 80 cm2to 30000 cm2, preferably from 200 cm2to 20000 cm2, more preferably from 300 cm2to 10000 cm2.

[0023] An optical blocking of the cross section of the abrasion protection element in the main flow direction may be from 90 % to 100 %. An open or free cross section in main flow direction may be from 0 % to 10 %, preferably from 0% to 5 %. A free flow cross section in one layer may be from 10 % to 75 %, preferably from 25 % to 50 %. A gap between the flow guiding elements of one layer may be from 5 to 100 mm, preferably from 10 mm to 85 mm, more preferably from 20 mm to 50 mm.

[0024] The flow guiding elements of the different layers may be arranged that projections in main flow direction of two consecutive layers at least partially overlap, e.g. by 0 to 50 %.

[0025] The terms "first", "second" and other terms of a similar nature are used as nomenclature, without hereby order or ranking. Also, several "first" or "second" properties and / or elements may be provided.

[0026] The abrasion protection element may be arranged transversely to the main flow direction, e.g. at the inlet of the quench cooler. The term “transversely to a main flow direction” as used herein is a broad term and is to be given its ordinary and customary meaning to a person of ordinary skill in the art and is not to be limited to a special or customized meaning. The term specifically may refer, without limitation, to an arrangement in which the flow grid is completely parallel to the main flow direction, wherein deviations are possible. In other words, the flow grid can preferably be arranged perpendicular to the main flow direction.

[0027] At least some of the flow guiding elements may be arranged such that a scattering surface forms an angle with respect to the main flow direction such that the grid plane is arranged nonparallel to the main flow direction. For example, a normal of the respective flow guiding element may form an angle with the main flow direction. The angle may depend on the design of the flow guiding element. The term “flow guiding element” as used herein is a broad term and is to be given its ordinary and customary meaning to a person of ordinary skill in the art and is not to be limited to a special or customized meaning. The term specifically may refer, without limitation, to an element configured for influencing a fluid flow impinging on the abrasion protection element. For example, the flow guiding element may be configured for scattering and / or reflecting particles of the fluid flow. For example, the flow guiding element may comprise a bar, i.e. an elongated element that is longer than it is wide, such as a rod. However, other embodiments of flow guiding elements are possible.

[0028] For example, the flow guiding elements may comprise a geometric body comprising a polygonal or circular base. The polygonal or circular base may form a length and width of the flow guiding element. The base may be arranged with respect to the main flow direction forming an angle of attack.

[0029] For example, the flow guiding elements may have a conical shape, a tapered shape, a pyramidal shape, or a plate-like shape.

[0030] For example, the flow guiding element may be a cone or a truncated cone. The cone may be a three-dimensional geometric body that tapers from a base, e.g. a circular base, to an apex. The base may be flat or even curved or arched.

[0031] For example, the flow guiding element may have pyramidal shape. The flow guiding element may have a regular polygonal base. The flow guiding element may be a pyramid tetrahedron, a square pyramid, a pentagonal pyramid, or a hexagonal pyramid. For example, the flow guiding element may be a truncated pyramid. The base may be flat or curved or arched.

[0032] For example, each of the flow guiding elements may be or may comprise a panel. The term “panel” as used herein is a broad term and is to be given its ordinary and customary meaning to a person of ordinary skill in the art and is not to be limited to a special or customized meaning. The term specifically may refer, without limitation, to a three dimensional structure having two opposing surfaces having a length and a width perpendicular to a surface normal and a thickness which is smaller than the length and the width. The surface of the panel may be planar, curved, and / or arched. The panel may have a flat extension, e.g. a sheet and / or shell like element. The outer shape of the panel may circular, polygonal such as hexagonal. The geometrical shape of the flow guiding elements may be identical or different.

[0033] The abrasion protection element may comprise a plurality of flow guiding elements. The abrasion protection element may comprise a plurality of levels of flow guiding elements, wherein in each level at least one flow guiding element is positioned. The abrasion protection element may comprise from 2 to 20 levels, preferably from 2 to 10 levels, more preferably from 2 to 5 levels. For example, the abrasion protection element may comprise two, three, four, five, six or even more levels. In an embodiment, the abrasion protection element may comprise three levels. The levels may be spaced from each other in a direction from an entrance of the abrasion protection element for receiving the particles, e.g. of the gas stream, to an outlet of the abrasion protection element. A first end of the support structure may form the entrance of the abrasion protection element and a second, in particular opposing, end may form the outlet of the abrasion protection element. For example, the levels may be arranged one after the other in a main flow direction. The flow guiding element may be positioned at different levels between the entrance of the abrasion protection element and the outlet of the abrasion protection element. The levels may be positioned equidistant along the rotational axis or may have different distances between each other. The distances between the levels may be from - 50 mm to 500 mm, preferably from -20 mm to 200 mm, more preferably from 0 to 100 mm. The distance may be measured from a lower edge of the flow guiding element to a point directly below the upper edge of the lower flow guiding element.

[0034] The abrasion protection element may be axially symmetric with respect to a rotational axis extending from the entrance to the outlet through a center of the abrasion protection element. However, other embodiments, e.g. non-axially symmetric embodiments are feasible.

[0035] The support structure, in particular at least one holder, may surround the flow guiding elements. The support structure may form at least one outer wall or housing of the abrasion protection element. The support structure may comprise a single holder, e.g. monolithic, surrounding the flow guiding elements or a plurality of holders forming together the outer wall or housing or connecting element(s) between the abrasion protection element and e.g. a steam cracker. The single holder may comprise at least one recess and / or at least one opening.

[0036] The support structure may comprise a lower holder. The lower holder may function in additional as flow guiding element. The lower holder may comprise a perforated plate. A center of the lower holder may be closed or covered. This can allow preventing free path of central jets. The lower holder may be positioned as first element at the entrance of the abrasion protection element, in particular below (with respect to direction of gravity) the last flow guiding element of the abrasion protection element. The lower holder may be configured for securing the flow guiding elements downwards and / or for intercepting detaching parts.

[0037] The support structure may provide supporting points for the flow guiding elements. For example, the support structure may comprise one or more of ribs, recesses, supports, carriers, protrusions and the like for positioning and / or holding the flow guiding elements. The support structure may provide for each of the flow guiding elements an identical or a different number of supporting points. For example, the support structure may provide for each of the flow guiding elements 3 to 60 supporting points, preferably 4 to 20, more preferably 4 to 10 supporting points. The supporting points may form a continuous or non-continuous groove. For example, in case of the flow guiding elements have a circular base, the supporting points may form a supporting ring, e.g. a continuous ring or a non-continuous ring. For example, the support structure may form a cone-shaped abrasion protection element. A diameter of the support structure may be tapered, e.g. from the outlet to the entrance. For example, the holder may taper from the outlet to the entrance. For example, a distance between the holders of the support structure may increase from the entrance of the abrasion protection element to the outlet of the abrasion protection element.

[0038] Each of the flow guiding elements may comprise a scattering surface. The scattering surface may be at least partially in a plane formed by the length and the width of the flow guiding element, e.g. in case of a flat panel. In case of an arched or curved flow guiding element, the scattering surface may be a two-dimensional surface area which is arched or curved with respect to the rotational axis. In case of a conical abrasion protection element, the diameters, and, thus, the scattering surface, of the flow guiding elements may increase from the entrance of the abrasion protection element to the outlet of the abrasion protection element.

[0039] A surface area of the scattering surface may be from 10 cm2to 10000 cm2, preferably from 30 cm2to 5000 cm2, more preferably from 50 cm2to 1000 cm2.

[0040] For example, the flow guiding element may comprise a plurality of openings for allowing a flow through the abrasion protection element. The scattering surface may be perforated. An open cross section may be from 5 % to 90 %, preferably from 10 to 80%, more preferably from 20 to 60 %.

[0041] The scattering surfaces may be inclined with respect to the rotational axis. For example, an angle of attack of the flow guiding elements, for both in and against the direction of flow, may be from 5° to 90°, preferably from 10° to 80°.

[0042] For example, the scattering surface may be circular such as a ring or polygonal such as a triangle, a square, or a rectangle. For example, in case of a polygonal scattering surface, the scattering surface may have from 3 to 60 sides, preferably 4 to 20 sides, more preferably from 4 to 10 sides. For example, the scattering surface may be regular or non-regular. For example, the scattering surface may be trapezoidal. For example, the scattering surface may be a parallelogram.

[0043] The flow guiding elements of the different levels may be arranged that projections in main flow direction of two consecutive levels at least partially overlap, e.g. by 0 to 100 %, preferably from 5% to 90 %, more preferably from 10 % to 80 %.

[0044] Each of the flow guiding elements may provide at least one scattering surface for scattering impinging particles. The term “scattering surface” as used herein is a broad term and is to be given its ordinary and customary meaning to a person of ordinary skill in the art and is not to be limited to a special or customized meaning. The term specifically may refer, without limitation, to a surface configured for scattering particles of the fluid flow, in particular in a defined direction. The scattering surface of the flow guiding elements may be oriented such that one or more of the following conditions are fulfilled: a flow cross section of the abrasion protection element is closed; a minimum pressure loss is ensured; flow after passing the abrasion protection element is symmetrical; carbon accumulation is prevented. The scattering surface of the flow guiding elements may form a contiguous area or may be distributed over a scattering area. For example, the flow guiding element may be designed as a perforated panel or may be designed as a plurality of rods.

[0045] The shape of the flow guiding elements may be such that deposited particles can trickle off such that a flow cross section of the abrasion protection elements remains free.

[0046] For example, the shape of the flow guiding element may be one or more of rod-like, polygonal or disc-shaped. The surface of the flow guiding elements may be plane, curved or kinked. A cross section may be convex such as circular, elliptical or polygonal, or concave such as V- shaped or C-shaped. The convex cross section may be an isosceles triangle, a rectangle, a rhombus or a regular polygon. A cross section in case of a disc-shaped flow guiding element may be triangular, square, trapezoidal or a parallelogram.

[0047] For example, the flow guiding element may have rod-like shape. For example, the flow guiding element may be roof-shaped or wing-shaped. The flow guiding element may not be troughshaped. An opening angle may be from 30° to 150°, preferably from 60° to 120°, more preferably from 75° to 105°.

[0048] For example, the flow guiding element may have an L-profile or V-profile. For example, in case of an L-profile a side length of the sides forming the L may be 20.5 mm and 22 mm. The sides of the L- or V-profile may be used as scattering surfaces.

[0049] Other profiles are possible such as C-profiles. The design of the flow guiding element may be defined using CFD simulations to ensure optimal flow conditions through the abrasion protection grid.

[0050] The flow guiding elements may be aligned and / or oriented with respect to a center of the abrasion protection element, e.g. defined by a center of the support structure. For example, flow guiding elements on a first side with respect to the center may have a first orientation and flow guiding elements on a second side with respect to the center may have second orientation different from the first orientation. For example, the second orientation may be a mirrored orientation of the first orientation. Flow guiding elements within a center region may have a third orientation. The orientation of the flow guiding elements can allow for homogenizing the incoming fluid flow. Moreover, entrained particles are slowed down. This can protect the tube shield of the quench cooler against abrasion. Moreover, the uniform distribution of the flow can permit optimal residence time distribution of the product gas in the quench cooler. This can have a positive effect on the product yield as well as on thermal efficiency of the quench cooler. Each of the flow guiding elements comprises a core of Oxide Ceramic Matrix Composite, OCMC, and a protective ceramic cover covering of the core.

[0051] The term “core” as used herein is a broad term and is to be given its ordinary and customary meaning to a person of ordinary skill in the art and is not to be limited to a special or customized meaning. The term specifically may refer, without limitation, to a central and / or inner part of the flow guiding element.

[0052] The term “protective cover” as used herein is a broad term and is to be given its ordinary and customary meaning to a person of ordinary skill in the art and is not to be limited to a special or customized meaning. The term specifically may refer, without limitation, to a part of the flow guiding element surrounding and / or enveloping the core and configured for protecting the core from abrasion. The protective cover may further be configured for protecting the core against chemical influences.

[0053] The use of OCMC can allow increasing resistance to thermal and mechanical shocks. For example, a fracture toughness of OCMC can reach values of KIC = 10 - 50 MPaVm. A thermal shock resistance can be ensured; critical temperature difference ATC according to DIN V ENV 820-3: ATC > 800 K > 600 K > 500 K. The use of the protective ceramic cover can increase abrasion resistance and chemical passivity. The combination of OCMC and the protective ceramic cover can lead to an increased lifetime of the abrasion protection element, and therefore increased cracker runtimes.

[0054] The term “Ceramic Matrix Composite (CMC)” as used herein is a broad term and is to be given its ordinary and customary meaning to a person of ordinary skill in the art and is not to be limited to a special or customized meaning. The term specifically may refer, without limitation, to an arbitrary composite material, specifically to an arbitrary fiber-reinforced composite material, comprising a plurality of ceramic fibers embedded in a ceramic matrix. Thereby, carbon and carbon fibers may also be regarded as a ceramic material. The term “composite material” as used herein is a broad term and is to be given its ordinary and customary meaning to a person of ordinary skill in the art and is not to be limited to a special or customized meaning. The term specifically may refer, without limitation, to an arbitrary material being produced from two or more constituent materials. These constituent materials may have notably dissimilar chemical or physical properties and may be merged to create a material with properties unlike the individual materials. Within the composite material, the individual materials may remain separate and distinct. Specifically, the composite material may be a fiber-reinforced composite material. The term “fiber-reinforced composite material (FRC)” as used herein is a broad term and is to be given its ordinary and customary meaning to a person of ordinary skill in the art and is not to be limited to a special or customized meaning. The term specifically may refer, without limitation, to an arbitrary material generally comprising at least two main components: reinforcing fibers and an embedding matrix which may serve as a filler and / or adhesive between the fibers. Mutual interactions between the two components may give overall material higher-grade properties than either of the two components involved alone. The fiber-reinforced composite (FRC) may specifically comprise the fibers as a discontinuous or dispersed phase, the matrix as a continuous phase and an interphase region, which may also be referred to as interface.

[0055] The term “Oxide Ceramic Matrix Composite (OCMC)” as used herein is a broad term and is to be given its ordinary and customary meaning to a person of ordinary skill in the art and is not to be limited to a special or customized meaning. The term specifically may refer, without limitation, to an arbitrary ceramic matrix composite comprising an oxide ceramic matrix reinforced by oxide ceramic reinforcing fibers. The term “OCMC” may refer to pure OCMC structures and to hybrid OCMC structures comprising in addition to the OCMC at least one further material such as metallic fibers. Specifically, OCMCs are fiber reinforced composite materials comprising oxide fibers embedded in a porous matrix of oxide ceramics. Advantages of such OCMCs can be ensuring high temperature resistance up to 1300 °C or above, high thermal shock resistance and quasi-ductile deformation and fracture behavior. An open porosity E of fiber composite ceramics can usually take on values between 5% and 50%. As a result of the porous structure, fiber composite ceramics may have a lower density, a lower modulus of elasticity and a lower thermal conductivity coefficient compared to monolithic ceramics with the same chemical composition. The following table gives a list of the relevant standards for the determination of these parameters; in particular a list of relevant norms for the determination of structural, mechanical and thermophysical parameters for monolithic ceramics and for OCMC.

[0056] The thermal conductivity coefficient is defined by the following relationship: thermal conductivity coefficient = density x (specific heat capacity) x thermal diffusivity coefficient.

[0057] As an example, the following table compares between the properties of monolithic ceramics and OCMC based on aluminum oxide.

[0058] For example, the OCMC may be prepared by the following manufacturing procedure: A fiber fabric in the form of a textile or a fiber bundle such as a rovings may be infiltrated with a slurry. The infiltration may be carried out by dipping or knife coating. Several layers may be laminated over a suitable mold until a desired wall thickness is achieved. Drying may be carried out in a temperature range of 40 °C to 150 °C, preferably from 60 °C to 100 °C. In a subsequent step, the OCMC layer may be fired. Firing may take place in a temperature range of 1100 °C to 1300 °C, preferably in a temperature range of 1150 °C to 1250 °C.

[0059] Specifically, components made of OCMs may be manufactured using a manufacturing process as described, for example, in DE102016007652A1 , comprising the following steps: The textile framework is impregnated with a slurry and placed on a mold or laminated. A slurry may be understood to be the pulpy to pasty mixture of water and mineral powder, which is used as a raw mass for the production of ceramic products. For example, the powder contains metal oxides, carbides, nitrides. Preferably, the powder contains aluminum oxide, zirconia, mullite or zirconia reinforced aluminum oxide. Subsequently, the component is dried at temperatures of 40 °C to 150 °C, preferably from 60 °C to 100 °C. This can allow giving the component sufficient stability that it is self-supporting and can be removed from the mold. Finally, the component may be fired in a high-temperature furnace at temperatures of 1100°C to 1300°C, preferably in a temperature range of 1150 °C to 1250 °C. The finished component may comprise an intimate composite of the textile framework and a sintered, porous ceramic matrix.

[0060] However, also other manufacturing processes may be possible.

[0061] As outlined above, the OCMC may have a matrix, specifically an oxide ceramic matrix. The term “matrix” as used herein is a broad term and is to be given its ordinary and customary meaning to a person of ordinary skill in the art and is not to be limited to a special or customized meaning. The term specifically may refer, without limitation, to an arbitrary constituent of a composite material. Specifically, the matrix may refer to or may comprise at least one material in which other components are embedded. The matrix may specifically serve the following functions. The matrix may be configured for binding a fiber reinforcement. Further, the matrix may be configured for providing a composite component its shape and may direct its surface quality.

[0062] The matrix may specifically comprise at least one of: a binary oxide (MXOZ); a mixed oxide such as M1xM2yOz and / or M1xM2yM3wOz; a complex matrix comprising a plurality of ceramic particles and / or of metallic particles. Specifically, the OCMC may have a matrix composition selected from the group consisting of: SixMyOz, SixM1yM2wOz, SixByNzCw, AIN, MxOyand mixtures of oxides (M1xOy / M2wOz). For example, the OCMC may have a matrix composition comprising a mixture of oxides such as 85% AI2O3 and 15% ZrO2 (e.g. a matrix available under FW12 from WPS). However, also other kinds of materials may be possible. Thereby, O may refer to the chemical element oxygen. B may refer to the chemical element boron (B). N may refer to the chemical element nitrogen (N) and C may refer to the chemical element carbon (C).

[0063] M may specifically be an element selected from the group consisting of: aluminum (Al), zirconium (Zr), silicon (Si), calcium (Ca), magnesium (Mg), beryllium (Be), yttrium (Y), lanthanum (La), iron (Fe), nickel (Ni), chromium (Cr), tungsten (W), hafnium (Hf), strontium (Sr). Preferably, M may be an element selected from the group consisting of: aluminum (Al), zirconium (Zr), silicon (Si), strontium (Sr), lanthanum (La), yttrium (Y). M1 may specifically be an element selected from the group consisting of: aluminum (Al), zirconium (Zr), yttrium (Y). Preferably, M 1 may be aluminum (Al). M2 may specifically be an element selected from the group consisting of: zirconium (Zr), silicon (Si). Preferably, M2 may silicon (Zr). M3 may specifically be cobalt (Co), x, y and w may each independently be between 1 and 10, preferably between 1 and 7 and most preferably between 1 and 5. z may specifically be between 1 and 30, preferably between 1 and 20 and most preferably between 1 and 10.

[0064] The OCMC may have a porosity from 10 % to 60 %, preferably from 20 % to 50 %, more preferably from 20 % to 40%. A pore size, specifically the matrix of the OCMC, may specifically be between 0.001 pm and 100 pm, preferably between 0.01 pm and 10 pm and most preferably between 0.05 pm and 0.5 pm. However, also other embodiments may be possible.

[0065] As outlined above, the OCMC may have a plurality of fibers, specifically a plurality of oxide ceramic reinforcing fibers. The term “fiber” as used herein is a broad term and is to be given its ordinary and customary meaning to a person of ordinary skill in the art and is not to be limited to a special or customized meaning. The term specifically may refer, without limitation, to an arbitrary element having a length and a width, wherein the length of the element exceeds the width of the element such as at least by a factor of 5, preferably at least by a factor of 10 and most preferably at least by a factor of 20. The fiber may specifically be an artificial fiber. The artificial fiber may be a fiber whose chemical composition, structure, and / or properties may be significantly modified during a manufacturing process. Artificial may refer to regenerated fibers and synthetic fibers.

[0066] The oxide ceramic reinforcing fibers may comprise at least one material selected from the group consisting of: a binary oxide (MXOZ), a mixed oxide (M1xM2yOzor M1xM2yM3wOz), a metal (M), a metal carbide (MxCy). Specifically, OCMC may have oxide ceramic reinforcing fibers comprising at least one material selected from the group consisting of: mullite, AI2O3, a combination of mullite and AI2O3. However, also other kinds of materials may be possible.

[0067] Thereby, O may refer to the chemical element oxygen (O) and C may refer to the chemical element carbon (C).

[0068] M may specifically be an element selected from the group consisting of: aluminum (Al), zirconium (Zr), silicon (Si), calcium (Ca), magnesium (Mg), beryllium (Be), yttrium (Y), lanthanum (La), iron (Fe), nickel (Ni), chromium (Cr), tungsten (W), hafnium (Hf), strontium (Sr),. Preferably, M may be selected from the group consisting of: aluminum (Al), silicon (Si), strontium (Sr), zirconium (Zr), lanthanum (La), yttrium (Y). M1 may specifically be an element selected from the group consisting of: aluminum (Al), zirconium (Zr), yttrium (Y). Preferably, M1 may be aluminum (Al). M2 specifically be an element selected from the group consisting of: silicon (Si), zirconium (Zr). Preferably, M2 may be silicon (Si). M3 may specifically be cobalt (Co), x, yand w may each independently be between 1 and 10, preferably between 1 and 7 and most preferably between 1 and 5. zmay specifically be between 1 and 30, preferably between 1 and 20 and most preferably between 1 and 10.

[0069] The OCMC may have a plurality of the oxide ceramic reinforcing fibers which may form a fiber fabric. The term “fiber fabric” as used herein is a broad term and is to be given its ordinary and customary meaning to a person of ordinary skill in the art and is not to be limited to a special or customized meaning. The term specifically may refer, without limitation, to a manufacturing of the fibers. The fiber fabric may be manufactured in a sheet, a mat, specifically a continuous mat, or as continuous filaments. The fiber fabric may be manufactured from at least one technique selected from the group consisting of: weaving, knitting, braiding and stitching. The fibers may be manufactured in two-dimensional or three-dimensional orientations. In the two-dimensional orientation the fibers may be essentially only aligned along a plane in x-direction, and in y-direction of the material. In the three-dimensional orientation fibers may be incorporated in the x-direction, y-direction and z-direction. The fiber fabric may also be referred to as fiber preform, fiber backbone, fiber scaffold or fiber framework.

[0070] The fiber fabric may have a mesh, a woven or a knitted structure. However, also other embodiments may be feasible. The fiber fabric may specifically be woven in a weave pattern selected from the group consisting of: unidirectional, plain weave, twill K1 / 2, twill K2 / 2, twill K1 / 3, twill 4 / 4, atlas A1 / 4, atlas A1 / 7. Preferred weave patterns may be twill 2 / 2, twill 4 / 4, atlas 1 / 4, atlas 1 / 7, and specifically twill 4 / 4, atlas 1 / 4 and atlas 1 / 7. The fiber fabric may specifically be laminated at an angle of 0 / 90° or at an angle of 45°. However, also other embodiments may be feasible.

[0071] The fiber fabric may be a homogeneous fiber fabric or a hybrid fiber fabric. Specifically, the hybrid fiber fabric may also be part of a functional layer. The homogeneous fiber fabric may comprise exclusively one kind of fibers. The hybrid fiber fabric may comprise at least two different kinds of fibers. One kind of fibers of the hybrid fiber fabric may refer to fibers being electrically conductive. The fiber fabric may specifically comprise electrically conductive fibers as warp and / or weft threads. Preferably, the fiber fabric may comprise electrically conductive fibers as weft threads. The fibers being electrically conductive may comprise at least one of metals, carbon and silicon carbide, preferably at least one of metal and carbon and most preferably metal. The metallic fibers may be made of at least one material selected from the group consisting of: an iron-based alloy, a nickel-based alloy, a platinum group metal (PGM) or a refractory metal. The metallic fibers may specifically be made of at least one ferritic iron-chromium-aluminum alloy (FeCrAI alloy) or one alloy having a material number according to DIN 17007-2:1961-09: n1 .ml m2m3m4. n1 may specifically be a digit from the group 1 ,2,3 and preferably a digit from the group 1 and 2. ml may specifically be a digit from the group 0, 1 , 3, 4, 8, preferably a digit from the group 3 and 4 and particularly preferably the digit 4. m2 may specifically be a digit from the group 0, 1 , 2, 3, 4, 5, 6, 7, 8, 9, preferably a digit from the group 5, 6, 7, 8, 9 and particularly preferably a digit from the group 7, 8, 9. m3 and m4 preferably each independently may stand for one of the digits from the group 0, 1 , 2, 3, 4, 5, 6, 7, 8, 9. FeCrAI alloys comprise for example products distributed under the trade name Kanthal® AF, Kanthal® A-1 , Kanthal® D. PGM comprise the elements platinum, palladium, iridium, rhodium, osmium, ruthenium and alloys thereof. Refractory metals comprise the elements titanium, zirconium, hafnium, niobium, molybdenum, tantalum, tungsten, rhenium and alloys thereof.

[0072] The oxide ceramic reinforcing fibers may have a fiber diameter from 1 pm to 50 pm, preferably from 3 pm to 30 pm and most preferably from 5 pm to 20 pm. However, also other dimensions may be possible. However, also other dimensions are possible.

[0073] A plurality of single oxide ceramic reinforcing fibers, which may also be referred to as filaments, may be bundled to a strand, wire or yarn. Thereby, the plurality of single oxide ceramic reinforcing fibers may essentially extend in one direction. Specifically, the filaments may be twisted into a single yarn strand. One yarn strand may comprise 100 to 20000 filaments, preferably 200 to 10000 filaments. A yarn thickness according to ISO1144 may specifically be in the range of 50 to 2500 Tex, preferably in the range of 100 to 1500 Tex, most preferably in the range of 150 to 1000 Tex. A yarn may specifically be made of 200 to 10000 filaments, preferably of 300 to 3000 filaments, and most preferably of 300 to 2000 filaments. A fiber volume content may specifically be from 5% to 75%, preferably from 10% to 60% and most preferably from 20% to 50%. A diameter of the filaments may be from 1 pm to 50 pm, preferably from 3 pm to 30 pm, more preferably from 5 pm to 20 pm.

[0074] In an exemplary embodiment, a fiber fabric may comprise six superimposed fabric sheets wound in 0 / 90° orientation, e.g. of type DF-11 from 3M (St. Paul, MN, U.S.A.) which may be impregnated with slurry forming the matrix of the OCMC structure after firing. The slurry may comprise a mixture of 85% AI2O3 and 15% ZrC>2. The slurry may comprise additional components.

[0075] The core of OCMC may have a thermal expansion coefficient from 0 to 10 10’6 / K, preferably of 5 10-6 / K to 8 10-6 / K.

[0076] The core of OCMC may have a thickness from 1 mm to 10 mm, preferably from 1 .5 mm to 7 mm, more preferably from 2 mm to 5 mm.

[0077] The protective cover may comprise at least one ceramic. The protective cover may comprise at least one oxide, carbide or nitride. The protective cover may comprise at least one abrasion resistant ceramic, e.g. selected from the group consisting of: AI2O3, SisN i, SiC, B4C. The abrasion resistance of the protective cover may be expressed in terms of its hardness as determined by DIN EN 843-4:2005. The hardness number is from 0.5 to 4 GPA, preferably from 1 to 3 GPa. The abrasion resistance may be defined as “Vickers-Harte” according to DIN EN ISO 6507- 1 / 2 / 3 / 4:2018. The protective cover may have a thermal expansion coefficient from 0 to 10 10-6 / K, preferably of 5 10’6 / K to 8 10’6 / K. The protective cover may have a chemical passivity as described in Brevier Technische Keramik (ISBN 3-924158-77-0), page 101 , table 9.

[0078] The protective ceramic cover may have a thickness from 0.05 mm to 2 mm, preferably from 0.1 mm to 1 .5 mm, more preferably from 0.2 mm to 1 mm.

[0079] The protective cover may be a protective ceramic cover. A difference in thermal expansion coefficient between the protective ceramic cover and the core of OCMC may be from -2 10’6 / K to 2 10’6 / K, preferably from -1.5 10’6 / K to 1.5 10’6 / K, more preferably from -1 10’6 / K to 1 10’6 / K.

[0080] The protective cover may comprise one or more of tiles, fragments, or granules, and / or may be applied as coating.

[0081] For example, the flow guiding element may comprise a core of OCMC and a protective ceramic cover covering of the core.

[0082] For example, the flow guiding element may comprise a layer of OCMC sandwiched between two layers of ceramic.

[0083] For example, the flow guiding element may comprise a ceramic rod or a ceramic tube covered with OCMC, e.g. a hybrid bar. The layer of OCMC can allow providing an abrasion resistant layer.

[0084] Other combinations of layers of OCMC and ceramic are thinkable.

[0085] The adhesive may be one or more of a glass sealant, solder glasses, glaze or a ceramic adhesive.

[0086] The adhesive may have a softening temperature from 700 °C to 1250 °C, preferably from 750 °C to 1200 °C, more preferably from 800 °C to 1150 °C. A difference in thermal expansion coefficient between the adhesive and the core of OCMC may be from -2 10’6 / K to 2 10’6 / K, preferably from -1 .5 10’6 / K to 1 .5 10’6 / K, more preferably from -1 10’6 / K to 1 10’6 / K.

[0087] The abrasion protection element comprises at least one support structure. The term “support structure” as used herein is a broad term and is to be given its ordinary and customary meaning to a person of ordinary skill in the art and is not to be limited to a special or customized meaning. The term specifically may refer, without limitation, to an element of the abrasion protection element configured for providing at least one supporting function. The supporting function comprises mounting the flow guiding elements. For example, the mounting may comprise arranging and / or orienting the flow guiding elements. For example, the supporting function may be providing stiffness and / or strength e.g. against internal and / or external loads. The support structure may comprise 1 to 8, preferably 2 to 4 holders. The holders may have a width from 200 mm to 1500 mm, preferably from 500 mm to 1000 mm, more preferably from 600 m to 800 mm. The holders may have a height from 50 mm to 500 mm, preferably from 100 mm to 200 mm. The holders may have a thickness of 1 mm to 20 mm, preferably from 2 mm to 15 mmm, more preferably from 3 to 10 mm.

[0088] The holders may be arranged having an inclination against main flow direction from 0 to 30°, preferably from 0 to 15°, more preferably from 0 to 5°.

[0089] An angle between the longitudinal axis of two neighboring holders may be from 0 to 30°, preferably from 0 to 15°, more preferably from 0 to 5°.

[0090] An angle of tangent against radius of duct cross section may from 0° to 90°, preferably from 30° to 90°.

[0091] The flow guiding elements may be passed through recesses in the holders. In this way, the flow guiding elements are fixed in the vertical and in the lateral position. However, they can move in the longitudinal direction and thereby ensure stressless compensation of deformation, e.g. due to thermal expansion of the flow grid. The recesses for holding the flow guiding elements may be arranged such that a distance of the flow guiding elements of two consecutive layers (vertical distance between the bottom edge of the upper layer and the top edge of the lower layer) is from -50 to 500 mm, preferably from -20 to 200 mm, more preferably from 0 to 100 mm. The distance may be defined by the height difference between the lower edge I the lowest point of the upper layer and the upper edge I the highest point of the lower layer. The distance is equal to zero if the bottom edge of the top layer and the top edge of the bottom layer are at the same height.

[0092] A ratio of a cross section of the recess to the cross section of the rod-shaped flow guiding element may be from 1 to 1.2, preferably from 1 to 1 .1 , more preferably from 1 to 1 .05.

[0093] A protrusion of the (rod-shaped) flow guiding elements over the holder may be from 5 to 500 mm, preferably from 5 to 200 mm, more preferably from 5 to 100 mm.

[0094] A number of support points e.g. floating bearings, of a (rod-shaped) flow guiding element, may be from 1 to 6, preferably from 2 to 4. Support points may be points at which an impact bar is supported by the holder. For example, a flow grid has more than two holder bars that are fixed to the tube sheet and through which an impact bar is guided. A distance between two neighboring support points of a (rod-shaped) flow guiding element may be from 100 mm to 2000 mm, preferably from 200 mm to 1500 mm, more preferably from 500 mm to 1000 mm.

[0095] A width of a gap between two flow guiding elements of one layer may be from 5 mm to 100 mm, preferably from 10 mm to 75 mm, more preferably from 20 mm to 50 mm. The support structure may be configured for aligning and / or orienting the flow guiding elements. As outlined above and in more detail below, the support structure may provide a frame for positioning the flow guiding elements with respect to each other. The frame may comprise means for positioning the flow guiding elements such as one or more of holders, openings, fastening elements and the like.

[0096] The flow guiding elements may be aligned and / or oriented such that one or more of the following conditions are fulfilled: a flow cross section of the abrasion protection element is closed; a minimum pressure loss is ensured; flow after passing the abrasion protection element is symmetrical; carbon accumulation is prevented. The alignment and / or orientation of the flow guiding elements may depend on the application and / or shape of the flow guiding elements.

[0097] As outlined above and in more detail below, the flow guiding elements may be rod-shaped, polygonal or disc-shaped. Thus, several embodiments are possible, wherein each of the embodiments provides a different scattering surface. For example, in order to realize a flow cross section of the abrasion protection element is closed, in case of rod-shaped flow guiding elements, e.g. having an L-profile or V-profile, the surfaces of the rods may be aligned to cover the cross section of the abrasion protection element at least to a large extend. The extend of coverage may be selected such that flow through and / or along the flow guiding elements in order to pass the abrasion protection element is still possible. For example, the surfaces of the flow guiding elements may be aligned to lie in a common plane, wherein the scattering surfaces exhibit deviations from the plane, e.g. forming an angle with the plane below 90°, preferably below 45°. The surfaces of the flow guiding elements providing the scattering surfaces may have different angles with the plane. Other embodiments are possible. For example, the abrasion protection element may comprise a plurality of flow guiding elements arranged subsequently in a main flow direction. The flow guiding elements of the different layers may be arranged complementary such that the flow guiding elements of subsequent layers supplement the coverage of the flow guiding elements of the previous layers.

[0098] For example, the orientation of the flow guiding elements may ensure that flow after passing the abrasion protection element is symmetrical. As outlined above, the flow guiding elements in different regions of the abrasion protection element may have different orientations, e.g. on a first side with respect to the center a first orientation, a mirrored orientation (second orientation) on a second side with respect to the center and in a center region a third orientation. Such an orientation can allow for homogenizing the incoming fluid flow and thus, may ensure that flow after passing the abrasion protection element is symmetrical.

[0099] For example, a ratio of a total free cross-section (i.e. the cross section not covered by the scattering surfaces of the flow guiding elements) provided by the entirety of the flow guiding elements, or a layer of the flow guiding elements, and a cross section of the abrasion protection element (channel cross-section) may be selected in order to ensure a minimum pressure loss. For example, the relative position of the flow guiding elements with respect to the main flow direction may be selected such that a minimum pressure loss is ensured. For example, in case of flow guiding elements having an open geometry such as concave, e.g. V-shaped, the rotation of the V by 90° or 180° can have a significant influence on the pressure drop of the system. For this reason CFD simulations were performed at a gas inlet velocity into the refractory-lined transfer duct from cracker to quench cooler of 235 m / s. Depending on the relative position of the flow guiding elements to the main flow direction the percentage pressure loss, at the inlet of the tube sheet of quench cooler, compared to a system without such elements, was found to be 12% for a 180° rotated V, 10.3% for a 90° rotated V and 9% for a non-rotated V. With the additional boundary condition of preventing possible coke depositions inside the flow guiding element, the best suited option may be the 90° rotated V as a flow guiding element.

[0100] For example, the shape of the flow guiding elements in combination with the orientation of the scattering surfaces can allow preventing carbon accumulation. For example, in case of flow guiding elements having an open geometry such as concave, e.g. V-shaped or C-shaped, the surfaces may be orientated such that no deposition area is provided.

[0101] The flow guiding elements and the support structure may form a rectangular grid. The support structure may comprise a frame comprising a first holder and an opposing second holder. Each of the first and the second holder may comprise a plurality of recesses for receiving the flow guiding elements. Each recess of the first holder has a corresponding recess in the second holder. The recesses may have identical, similar or different shapes.

[0102] The recesses may be configured as fixed bearing or floating bearing for the flow guiding element. The recesses and the flow guiding element may be selectively connected by force-fit and / or form-fit connections. The flow guiding elements may be connected to the supporting elements. Force-fit connections are used in fixed bearings and form-fit connections in floating bearings.

[0103] A distance between the first holder and the second holder may be adaptable. For example, an inner distance (along the z-axis) between the first holder and the second holder is adaptable from 100 mm to 2000 mm, preferably from 200 mm to 1500 mmm, more preferably from 500 mm to 1000 mm. The flow guiding elements may be movable, in particular slidable, along the recesses of the first holder and the second holder.

[0104] For example, the first holder and the second holder have a width (along the x-axis) from 200 mm to 1500 mm, preferably from 500 mm to 1000 mm, more preferably from 600 m to 800 mm. The first holder and the second holder may have a height (along the y-axis) from 50 mm to 500 mm, preferably from 100 mm to 200 mm.

[0105] For example, a total length of the flow guiding elements may be from 100 mm to 2000 mm, preferably the total length is from 200 to 1500 mm. The support structure comprises a layered structure comprising at least one layer of OCMC and at least one layer of ceramic. The term “layered structure” as used herein is a broad term and is to be given its ordinary and customary meaning to a person of ordinary skill in the art and is not to be limited to a special or customized meaning. The term specifically may refer, without limitation, to the fact that the support structure comprises a plurality of layers and / or elements.

[0106] In particular, the support structure comprises a sandwich structure of OCMC and ceramic. The layered structure may comprise at least one layer of OCMC and at least one layer of ceramic or a layer of OCMC sandwiched between two layers of ceramic. With respect to the definition and embodiments of OCMC reference is made to the description of the OCMC of the flow guiding elements as described above, or as described in more detail below. With respect to the definition and embodiments of the ceramic reference is made to the description of the protective ceramic cover of the flow guiding elements as described above, or as described in more detail below. The support structure may be made of the same material as the flow guiding elements.

[0107] For example, the support structure may comprise a core of OCMC and a protective ceramic cover covering of the core.

[0108] For example, the support structure may comprise a layer of OCMC sandwiched between two layers of ceramic.

[0109] The support structure may comprise a single OCMC layer or a sandwich structure comprising over its cross section a ceramic layer and an OCMC-layer or a sandwich structure comprising over its cross section a ceramic layer, an OCMC-layer and a ceramic layer or a sandwich structure comprising over its cross section a ceramic layer, an OCMC-layer, a ceramic layer, an OCMC-layer and a ceramic layer.

[0110] Other combinations of layers of OCMC and ceramic are thinkable.

[0111] The support structure may comprise at least one layer of adhesive, e.g. between the layers of OCMC and ceramic, e.g. between the core of OCMC and the protective ceramic cover and / or the sandwiched OCMC and the two layers of ceramic.

[0112] The support structure may have a geometry of a slab or a plate.

[0113] The protective cover may comprise one or more of tiles, fragments, or granules, and / or may be applied as coating.

[0114] The protective cover may comprise at least one ceramic. The protective cover may comprise at least one oxide, carbide or nitride. The protective cover may comprise at least one abrasion resistant ceramic, e.g. selected from the group consisting of: AI2O3, SisN i, SiC, B4C. The abrasion resistance of the protective cover may be expressed in terms of its harness as determined by DIN EN 843-4:2005 DE. The hardness number is 0.5 to 4 GPa, preferably 1 to 3 GPa on the Vickers scale. The protective cover may have a thermal expansion coefficient from 0 to 10 10-6 / K, preferably of 5 10’6 / K to 8 10’6 / K. The protective cover may have a chemical passivity as described in Brevier Technische Keramik (ISBN 3-924158-77-0), page 101 , table 9.

[0115] The surface of the holders may be flat or curved. The shape may be regular or irregular.

[0116] For example, the flow guiding elements and the support structure form a cone-shaped element. Each flow guiding element may comprise a circular disc. The circular discs may have different cross sections. The support structure may comprise a plurality of ribs configured for holding the circular discs. The flow guiding elements may have polygonal impact surfaces. The impact surfaces may be composed of a plurality of rib-shaped elements, e.g. plane panel elements.

[0117] In a further aspect, a quench cooler configured for cooling at least one gas stream is disclosed.

[0118] The quench cooler comprises at least one outer shell comprising at least one inlet for receiving the gas stream from a furnace and at least one outlet for providing the cooled gas stream; at least one header configured for providing at least one inlet and at least one outlet for at least one coolant; at least one tube bundle comprising a plurality of tubes configured for coolant flow through the tubes, wherein the tube bundle is housed by the outer shell, wherein the tube bundle comprises at least one inlet and at least one outlet for the coolant; at least one abrasion protection element according to the present invention, such as described in an embodiment of the first aspect of the present invention or as described in more detail below, wherein the abrasion protection element is arranged at the inlet for receiving the gas stream from the furnace.

[0119] With regard to embodiments and definitions, reference can be made to the description of the abrasion protection element above or as described in more detail below.

[0120] The gas stream may be generated in a furnace. For example, process gases may be hydrocarbons, hydrogen, exhaust gases, purge gases, inert gases, fuel gases, and the like.

[0121] For example, the furnace may be an industrial reactor furnace configured to carry out at least one process selected from the group consisting of: performing at least one endothermic reaction; cracking; steam cracking; steam reforming; alkane dehydrogenation; heating, preheating; superheating or for intermediate superheating of steam; styrene production by ethylbenzene dehydrogenation; production of acetylene, e.g. from natural gas; catalytic cracking; splitting ammonia for hydrogen production; hydrocyanic acid synthesis from hydrocarbons and ammonia; ammonia cracking (NH3 I / 2N2 + 3 / 2H2); methane steam reforming: CO + 3H2); cyanic acid from methane and ammonia (BMA) (CH4 + NH3-> HCN + 3H2); formamide cleavage (HCONH2 - HCN + H2O); Alkane dehydrogenation (CnH(2n+2) - CnH <2n) + H2, n-2, 3,4); styrene synthesis (CsH CsHs + H2); or Cyclohexane dehydrogenation (CeHi2 CeHe + 3H2); steam- or dry-reforming, e.g. steam- or dry-reforming of natural gas, blast furnace gas, associated gas and / or biogas; cement production, metallurgy. Additionally or alternatively to natural gas and methane, biogas and bio methane may be used.

[0122] For example, the gas stream comprises one or more of ethylene, CH4, C2H2, C2H4, C2H6, C3H6, C3H8, C4H6, C4H8, C4H10, CeHe, CO, CO2, H2, H2O, N2, O2. The gas stream may comprise particles such as coke or inorganic particles.

[0123] The coolant may be at least one coolant selected from the group consisting of: pressurized water, boiling water; thermal oil; molten salt; molten metal; gases such as H2, He, N2.

[0124] The term “quench cooler”, also denoted as transfer line exchanger (TLE), as used herein is a broad term and is to be given its ordinary and customary meaning to a person of ordinary skill in the art and is not to be limited to a special or customized meaning. The term specifically may refer, without limitation, to a heat exchanger configured for cooling at least one gas stream down to a predefined temperature. The quench cooler may be configured for cooling the gas stream, wherein the gas stream may comprise one or more of ethylene, CH4, C2H2, C2H4, C2H6, C3H6, C3H8, C4H6, C4H8, C4H10, C6H6, CO, CO2, H2, H2O, N2, O2.

[0125] For example, the gas stream has a temperature of 20 °C to 1400 °C, preferably 500 °C to 1200 °C, more preferably from 700 °C to 1000 °C. For example, the gas stream generated by steam cracking may leave the furnace at a high temperature such as of about 850 °C and must be cooled down, in particular in order to prevent secondary reactions. For example, the quench cooler may be designed as described in DE 3842727 C2, US 3802497, or H. Zimmermann et aL, “Ethylene”, Ullmann’s Encyclopedia of industrial Chemistry, 2012 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim, DOI: 10.1002 / 14356007. a10_045.pub3, the content of these documents is included herewith by reference.

[0126] The quench cooler comprises the outer shell. For example, the outer shell may be cylindrical. The outer shell may be arranged horizontal or vertical.

[0127] The outer shell may have one or more inlets for receiving the gas stream from the furnace. The inlet may be in fluid connection with at least one outlet of the furnace. The abrasion protection element is arranged at the inlet for receiving the gas stream from the furnace.

[0128] The outer shell may comprise one or more outlets through which the cooled gas stream can leave the quench cooler. The inlet(s) and the outlet(s) may arranged on the same or opposing sides of the outer shell. The outer shell may be configured for enabling passage of the gas stream through the outer shell (so-called “shell-side” flow). The outer shell further may house the tube bundle comprising a plurality of tubes. The outer shell may define a chamber configured for housing the tube bundle. The tube bundle comprises at least one inlet and at least one outlet for the coolant. The tubes may extend at least partially through the outer shell. The tubes may be straight or comprise one or more bends. The tubes carry the coolant from a respective inlet to a respective outlet (so-called “tube-side” flow). The coolant may be an arbitrary working fluid suitable for the respective application. The quench cooler may be configured for bringing the gas stream and the coolant, in thermal contact, in particular by using the tubes for coolant flow housed within the outer shell. The tubes may be made from a material suitable for heat transfer such as aluminum alloys, steel and the like. The quench cooler may comprise at least one header, e.g. on either side of the tube bundle. The header may provide a reservoir for the tube-side flow.

[0129] The quench cooler further may comprise at least one tube sheet. The tube sheet may be arranged at the inlet of the tube bundle. The support structure may be suspended from the tube sheet of the quench cooler and may be supported by the hood of the quench cooler. The tube sheet may be configured for securing, in particular the positions of the tubes, of the tube bundle. The abrasion protection element may be mounted to the tube sheet, e.g. via brackets.

[0130] In a further aspect, a transfer duct is proposed, wherein the transfer duct is configured for transferring a gas stream from a furnace to a quench cooler. The transfer duct comprises at least one abrasion protection element according to the present invention. The abrasion protection element is arranged at the outlet of the transfer duct.

[0131] In a further aspect, a steam cracker is disclosed. The steam cracker comprises at least one quench cooler according to the present invention, such as described above in an embodiment of the quench cooler or as described in more detail below, and / or a transfer duct, according to the present invention, such as described above in an embodiment of the quench cooler or as described in more detail below.

[0132] The steam cracker further comprises at least one furnace configured for steam cracking, e.g. including at least two operating modes: cracking mode and decoking mode. For example, the furnace may be run in the cracking mode. In the cracking mode feed containing hydrocarbons may be used to produce a gas stream comprising e.g. ethylene, acetylene, H2, etc.. In addition, soot may be generated. The soot may deposit (forming coke over time) inside the coils and may result in limiting a cross section and heat input and thus, the yield. The cracking may be stopped and the steam cracker may be run, e.g. repeatedly in defined time intervals, in the decoking mode. In the decoking mode, the soot and coke deposits may be oxidized using air, water vapor or a mixture thereof. Operating of a steam cracker is generally known to the skilled person such as from H. Zimmermann et aL, “Ethylene”, Ullmann’s Encyclopedia of industrial Chemistry, 2012 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim, DOI:

[0133] 10.1002 / 14356007. a10_045.pub3, the content of which is included herewith by reference. In both running modes, the particle load may be critical for the quench cooler. The abrasion protection element according to the present invention can allow protecting the quench cooler against the incoming particles.

[0134] The furnace may comprise at least one outlet for providing a gas stream to the quench cooler. The transition from the small furnace outlet diameter to the large inlet diameter of the quench cooler may be realized via a cone. Means for transition from the furnace outlet to the inlet of the quench cooler are generally known to the skilled person such as from chapter 5.2 “Quenching of Hot Cracked Gas” of H. Zimmermann et aL, “Ethylene”, Ullmann’s Encyclopedia of industrial Chemistry, 2012 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim, DOI:

[0135] 10.1002 / 14356007. a10_045.pub3, the content of which is included herewith by reference.

[0136] Summarizing and without excluding further possible embodiments, the following embodiments may be envisaged:

[0137] Embodiment 1 . An abrasion protection element comprising a plurality of flow guiding elements, wherein each of the flow guiding elements comprises a core of Oxide Ceramic Matrix Composite, OCMC, and a protective ceramic cover covering of the core; at least one support structure configured for mounting the flow guiding elements, wherein the support structure comprises a layered structure comprising at least one layer of OCMC and at least one layer of ceramic.

[0138] Embodiment 2. The abrasion protection element according to the preceding embodiment, wherein the layered structure comprises at least one layer of OCMC and at least one layer of ceramic or a layer of OCMC sandwiched between two layers of ceramic.

[0139] Embodiment 3. The abrasion protection element according to any one of the two preceding embodiments, wherein each of the flow guiding elements provides at least one scattering surface for scattering impinging particles.

[0140] Embodiment 4. The abrasion protection element according to any one of the preceding embodiments, wherein the support structure is configured for aligning and / or orienting the flow guiding elements.

[0141] Embodiment 5. The abrasion protection element according to any one of the preceding embodiments, wherein the flow guiding elements are aligned and / or oriented such that one or more of the following conditions are fulfilled: a flow cross section of the abrasion protection element is closed; a minimum pressure loss is ensured; flow after passing the abrasion protection element is symmetrical; carbon accumulation is prevented. Embodiment 6. The abrasion protection element according to any one of the preceding embodiments, wherein the flow guiding elements and the support structure form a rectangular grid, wherein the support structure comprises a frame comprising a first holder and an opposing second holder, wherein each of the first and the second holder comprises a plurality of recesses for receiving the flow guiding elements, wherein each recess of the first holder has a corresponding recess in the second holder.

[0142] Embodiment 7. The abrasion protection element according to the preceding embodiment, wherein a distance between the first holder and the second holder is adaptable, wherein the first holder and the second holder are movable along the flow guiding elements with respect to each other.

[0143] Embodiment 8. The abrasion protection element according to the preceding embodiment, wherein an inner distance between the first holder and the second holder is adaptable from 100 to 2000 mm, preferably from 200 to 1500 mmm, more preferably from 500 to 1000 mm.

[0144] Embodiment 9. The abrasion protection element according to any one of the three preceding embodiments, wherein the first holder and the second holder have a width from 200 mm to 1500 mm, preferably from 500 mm to 1000 mm, more preferably from 600 m to 800 mm, wherein the first holder and the second holder have a height from 50 mm to 500 mm, preferably from 100 mm to 200 mm.

[0145] Embodiment 10. The abrasion protection element according to any one of the three preceding embodiments, wherein a total length of the flow guiding elements is from 100 mm to 2000 mm, preferably the total length is from 200 to 1500 mm.

[0146] Embodiment 11 . The abrasion protection element according to any one of the preceding embodiments, wherein the flow guiding elements and the support structure form a cone- shaped element, wherein each flow guiding element comprises a circular disc, wherein the circular discs have different cross sections, wherein the support structure comprises a plurality of ribs configured for holding the circular discs.

[0147] Embodiment 12. The abrasion protection element according to any one of the preceding claims, wherein the flow guiding elements comprise a geometric body comprising a polygonal or circular base, wherein the flow guiding elements have a conical shape, a tapered shape, a pyramidal shape, or a plate-like shape.

[0148] Embodiment 13. The abrasion protection element according to any one of the preceding embodiments, wherein the protective cover comprises at least one ceramic selected from the group consisting of: AI2O3, SisN i, SiC, B4C. Embodiment 14. The abrasion protection element according to any one of the preceding embodiments, wherein the OCMC has a matrix composition selected from the group consisting of: SixMyOz, SixM1yM2wOz, SixByNzCw, AIN, MxOyand mixtures of oxides (M1xOy / M2wOz).

[0149] Embodiment 15. The abrasion protection element according to any one of the preceding embodiments, wherein the OCMC has oxide ceramic reinforcing fibers comprising at least one material selected from the group consisting of: mullite, AI2O3, a combination of mullite and AI2O3.

[0150] Embodiment 16. A quench cooler configured for cooling at least one gas stream, comprising at least one outer shell comprising at least one inlet for receiving the gas stream from a furnace and at least one outlet for providing the cooled gas stream; at least one tube bundle comprising a plurality of tubes configured for coolant flow through the tubes, wherein the tube bundle is housed by the outer shell, wherein the tube bundle comprises at least one inlet and at least one outlet for the coolant; at least one abrasion protection element according to any one of the preceding embodiments, wherein the abrasion protection element is arranged at the inlet for receiving the gas stream from the furnace.

[0151] Embodiment 17. The quench cooler according to the preceding embodiment, wherein the quench cooler comprises at least one tube sheet, wherein the abrasion protection element is mounted to the tube sheet.

[0152] Embodiment 18. The quench cooler according to any one of the preceding embodiments referring to a quench cooler, wherein the gas stream has a temperature from 20 °C to 1400 °C, preferably 500 °C to 1200 °C, more preferably from 700 °C to 1000 °C.

[0153] Embodiment 19. The quench cooler according to any one of the preceding embodiments referring to a quench cooler, wherein the gas stream comprises one or more of ethylene, CH4, C2H2, C2H4, C2H6, C3H6, C3H8, C4H6, C4H8, C4H10, C6H6, CO, CO2, H2, H2O, N2, O2.

[0154] Embodiment 20. A transfer duct configured for transferring a gas stream from a furnace to a quench cooler, wherein the transfer duct comprises at least one abrasion protection element according to any one of the preceding embodiments referring to an abrasion protection element, wherein the abrasion protection element is arranged at the outlet of the transfer duct. Embodiment 21 . A steam cracker comprising at least one quench cooler according to any one of the preceding embodiments referring to a quench cooler and / or a transfer duct according to any one of the preceding embodiments referring to a transfer duct, wherein the steam cracker further comprises at least one furnace configured for steam cracking.

[0155] Short description of the Figures

[0156] Further optional features and embodiments will be disclosed in more detail in the subsequent description of embodiments, preferably in conjunction with the dependent claims. Therein, the respective optional features may be realized in an isolated fashion as well as in any arbitrary feasible combination, as the skilled person will realize. The scope of the invention is not restricted by the preferred embodiments. The embodiments are schematically depicted in the Figures. Therein, identical reference numbers in these Figures refer to identical or functionally comparable elements.

[0157] In the Figures:

[0158] Figure 1 shows a longitudinal sectional view of inlet of a quench cooler in which an abrasion protection element is positioned;

[0159] Figure 2A and 2B show a perspective view and a frontal view onto the abrasion protection element fixed at the inlet tube sheet of the quench cooler;

[0160] Figure 3 shows an enlarged frontal sectional view onto the support structure;

[0161] Figure 4 shows an enlarged frontal sectional view onto the support structure and the mounting bracket; and

[0162] Figures 5A to 5C show an embodiment of an abrasion protection element positioned in a transfer duct.

[0163] Detailed description of the embodiments

[0164] Figure 1 shows a longitudinal sectional view of an exemplary inlet of a quench cooler in which the abrasion protection element 110 is positioned at the tube sheet 141 of quench cooler. A refractory-lined transfer duct 142 from a cracker to the quench cooler is depicted. Moreover, a hood 143 of quench cooler is shown.

[0165] The abrasion protection element 110 may be arranged transversely to the main flow direction 116, e.g. at the inlet of the quench cooler. The main flow direction 116 may be in a y direction. At least some of the flow guiding elements 112 may be arranged such that a scattering surface forms an angle with respect to the main flow direction such that the grid plane is arranged non- parallel to the main flow direction. For example, a normal of the respective flow guiding element 112 may form an angle with the main flow direction. The angle may depend on the design of the flow guiding element 112.

[0166] The abrasion protection element 110 may have a plurality of flow guiding elements 112 such as from 2 to 100, preferably from 2 to 50, more preferably from 2 to 30. A layer of flow guiding elements 112 may have 1 to 25, preferably 2 to 15 flow guiding elements. In the example of Figure 1 , the abrasion protection element comprises 25 flow guiding elements 112.

[0167] Figure 2A and 2B show an embodiment of an abrasion protection element 110. Figure 1 shows a sectional view. The abrasion protection element 110 may be configured for one or more of preventing, reducing or dampening influence of abrasion, in particular from impinging particles of a fluid flow, e.g. of product gas of a steam cracker, on an inlet of a quench cooler. The abrasion protection element 110 may be designed as a protective shield of the inlet of the quench cooler. The abrasion protection element 110 may be designed as an impingement element. The abrasion protection element 110 may be configured for influencing one or more of a direction, a distribution, an amount of an impinging fluid flow, e.g. by scattering, reflecting and the like.

[0168] The abrasion protection element 110 comprises at least one support structure 114 configured for mounting the flow guiding elements 112.

[0169] The flow guiding elements 112 may define a flow grid. The flow grid may have a plurality passages configured such that the fluid flow can flow through. The flow grid may comprise a plurality of layers, wherein each layer comprises a plurality of flow guiding elements 112. The flow grid may define a coordinate system. A main flow direction of the fluid flow may be along or parallel to a negative y-axis.

[0170] A length of the flow guiding elements 112 may be aligned essentially along or parallel to a z- axis. For example, a length of the flow guiding element 112 may be from 100 mm to 2000 mm, preferably from 200 mm to 1500 mm. A width of a projection of the flow guiding element 112 in main flow direction may be from 5 mm to 100 mm, preferably from 10 mm to 70 mm, more preferably from 15 mm to 50 mm. A width of a projection of the flow guiding element 112 perpendicular to the main flow direction may be from 5 mm to 100 mm, preferably from 10 mm to 70 mm, more preferably from 15 mm to 50 mm. A width of a stagnation area on the side of the flow guiding element 112 facing the flow may be from 0 to 70 mm, preferably from 0 to 50 mm. A width of a stagnation area on the side of the flow guiding element 112 facing away from the flow may be from 0 to 10 mm, preferably from 0 to 5 mm. A width of a stagnation area on the surface of the flow guiding element 112 facing away from the flow may be from 0 to 10 mm, preferably from 0 to 5 mm.

[0171] The flow guiding elements 112 may be arranged in the support structure 114 essentially along an x-axis at defined relative distances between neighboring flow guiding elements 112. For example, as shown in the embodiments of Figures 1 to 4, the flow grid may comprise two layers, i.e. a first layer and a second layer, of flow guiding element 112 stacked behind each other in the main flow direction (y-axis). The flow guiding elements 112 of the second layer may be arranged with an x-offset with respect to the x-positions of the flow guiding elements 112 of the first layer. The flow guiding elements 112 of the first and second layers may be arranged such that a complete cross-section of the abrasion protection element 110, impinged by the fluid flow, is covered.

[0172] The abrasion protection element 110 may have a cross sectional area, e.g. from 80 cm2to 30000 cm2, preferably from 200 cm2to 20000 cm2, more preferably from 300 cm2to 10000 cm2.

[0173] An optical blocking of the cross section of the abrasion protection element 110 in the main flow direction may be from 90 % to 100 %. An open or free cross section in main flow direction may be from 0 % to 10%, preferably from 0% to 5 %. A free flow cross section in one layer may be from 10 % to 75 %, preferably from 25 % to 50 %. A gap between the flow guiding elements of one layer may be from 5 to 100 mm, preferably from 10 mm to 85 mm, more preferably from 20 mm to 50 mm.

[0174] The flow guiding elements 112 of the different layers may be arranged that projections in main flow direction of two consecutive layers at least partially overlap, e.g. by 0 to 50 %.

[0175] The flow grid can preferably be arranged perpendicular to the main flow direction.

[0176] The flow guiding elements 112 may be configured for influencing a fluid flow impinging on the abrasion protection element 110. For example, the flow guiding elements 110 may be configured for scattering and / or reflecting particles of the fluid flow. For example, as shown in Figure 2A, the flow guiding elements may comprise a bar such as a rod.

[0177] Each of the flow guiding elements 112 may provide at least one scattering surface for scattering impinging particles. The scattering surface may be configured for scattering particles of the fluid flow, in particular in a defined direction. The scattering surface of the flow guiding elements 112 may be oriented such that one or more of the following conditions are fulfilled: a flow cross section of the abrasion protection element 110 is closed; a minimum pressure loss is ensured; flow distribution after passing the abrasion protection element 110 is symmetrical with respect to the orientation of the z-axis; carbon accumulation is prevented.

[0178] For example, in order to ensure a minimum pressure loss, the relative position of the flow guiding elements with respect to the main flow direction 116 can allow reducing the pressure drop. It was found that, in case of having V-shaped flow guiding elements 112, the rotation of the V by 90° or 180° has a significant influence on the pressure drop of the system. For this reason CFD simulations were performed at a gas inlet velocity into the refractory-lined transfer duct from cracker to quench cooler 142 of 235 m / s. Depending on the relative position of the flow guiding elements 112 to the main flow direction 116 the percentage pressure loss, at the inlet of the tube sheet of quench cooler 141 , compared to a system without such elements, was found to be 12%, 10.3% and 9% for a 180° rotated V, a 90° rotated V and a non-rotated V, respectively. With the additional boundary conditions of possible coke depositions inside a non-rotated V the best suited option was found in this simulations to be the 90° rotated V as shape and orientation for the flow guiding elements 112.

[0179] As shown in the overview in Figures 1 , 2A and 2B and with enlarged views in Figures 3 and 4, the flow guiding element 112 may have an L-profile. In this example, a side length of the sides forming the L may be 20.5 mm and 22 mm. The sides of the L-profile may be used as scattering surfaces. The design of the flow guiding element 112 may be defined using CFD simulations to ensure optimal flow conditions through the abrasion protection grid 110.

[0180] The recesses and the flow guiding element may be connected by force-fit and / or form-fit connections. As can be seen in Figures 3 and 4, a gap 118 may be present allowing for freedom of movement and protection against tilting.

[0181] Each of the flow guiding elements 112 comprises a core of Oxide Ceramic Matrix Composite, OCMC, and a protective ceramic cover covering of the core. The support structure 114 comprises a layered structure comprising at least one layer of OCMC and at least one layer of ceramic. The use of OCMC can allow increasing resistance to thermal and mechanical shocks. For example, a fracture toughness of OCMC can reach values of KIC = 10 - 50 MPaVm. A thermal shock resistance can be ensured; critical temperature difference ATC according to DIN V ENV 820-3: ATC > 800 K > 600 K > 500 K. The use of the protective ceramic cover can increase abrasion resistance and chemical passivity. The combination of OCMC and the protective ceramic cover can lead to an increased lifetime of the abrasion protection element, and therefore increased cracker runtimes.

[0182] The support structure 114 may be configured for mounting the flow guiding elements 112. For example, the mounting may comprise arranging and / or orienting the flow guiding elements 112. For example, the supporting function may be providing stiffness and / or strength e.g. against internal and / or external loads. The support structure 114 may be configured for aligning and / or orienting the flow guiding elements.

[0183] The support structure may comprise 1 to 8, preferably 2 to 4 holders 120, 122. The holders 120, 122 may have a width from 200 mm to 1500 mm, preferably from 500 mm to 1000 mm, more preferably from 600 m to 800 mm. The holders 120, 122 may have a height from 50 mm to 500 mm, preferably from 100 mm to 200 mm. The holders 120, 122 may have a thickness of 1 mm to 20 mm, preferably from 2 mm to 15 mmm, more preferably from 3 to 10 mm.

[0184] A distance between the first holder 120 and the second holder 122 may be adaptable. For example, an inner distance 126 (along the z-axis) between the first holder and the second holder is adaptable from 100 mm to 2000 mm, preferably from 200 mm to 1500 mmm, more preferably from 500 mm to 1000 mm. The flow guiding elements 112 may be movable, in particular slidable, along the recesses of the first holder 120 and the second holder 122.

[0185] The holders 120, 122 may be arranged having an inclination against main flow direction from 0 to 30°, preferably from 0 to 15°, more preferably from 0 to 5°.

[0186] An angle between the longitudinal axis of two neighboring holders may be from 0 to 30°, preferably from 0 to 15°, more preferably from 0 to 5°.

[0187] The recesses for holding the flow guiding elements 112 may be arranged such that such that a distance of the flow guiding elements of two consecutive layers (vertical distance between the bottom edge of the upper layer and the top edge of the lower layer) is from -50 to 500 mm, preferably from -20 to 200 mm, more preferably from 0 to 100 mm. The distance may be defined by the height difference between the lower edge I the lowest point of the upper layer and the upper edge I the highest point of the lower layer. The distance is equal to zero if the bottom edge of the top layer and the top edge of the bottom layer are at the same height.

[0188] A ratio of a cross section of the recess to the cross section of the rod-shaped flow guiding element 112 may be from 1 to 1 .2, preferably from 1 to 1 .1 , more preferably from 1 to 1 .05.

[0189] A protrusion of the (rod-shaped) flow guiding elements over the holder may be from 5 to 500 mm, preferably from 5 to 200 mm, more preferably from 5 to 100 mm.

[0190] A number of support points, e.g. floating bearings, of a (rod-shaped) flow guiding element 112 may be from 1 to 6, preferably from 2 to 4. A distance between two neighboring support points of a (rod-shaped) flow guiding element may be from 100 mm to 2000 mm, preferably from 200 mm to 1500 mm, more preferably from 500 mm to 1000 mm.

[0191] A width of a gap between two flow guiding elements 112 of one layer may be from 5 mm to 100 mm, preferably from 10 mm to 75 mm, more preferably from 20 mm to 50 mm.

[0192] In Figure 2A, the flow guiding elements 112 and the support structure 114 may form a rectangular grid. The support structure 114 may comprise a frame comprising a first holder 120 and an opposing second holder 122. As shown in Figures 2A and 2B, each of the first and the second holder 120, 122 may comprise a plurality of recesses 124 for receiving the flow guiding elements 112. The recesses 124 are best seen in Figures 3 and 4. Each recess 124 of the first holder 120 has a corresponding recess in the second holder 122.

[0193] The flow guiding elements 112 may be aligned and / or oriented with respect to a center of the abrasion protection element 110, e.g. defined by a center of the support structure 114. For example in the embodiment shown in Figures 1 and 2A, flow guiding elements 112 on a first side with respect to the center may have a first orientation and flow guiding elements 112 on a sec- ond side with respect to the center may have second orientation different from the first orientation. In particular, the second orientation may be a mirrored orientation of the first orientation with respect to the diagonal through the circular tubular mirror, which is parallel to the z-direc- tion. Flow guiding elements 112 within a center region may have a third orientation. The orientation of the flow guiding elements 112 can allow for homogenizing the incoming fluid flow.

[0194] A distance between the first holder 120 and the second holder 122 may be adaptable. For example, an inner distance 126 (along the z-axis) between the first holder and the second holder is adaptable from 100 mm to 2000 mm, preferably from 200 mm to 1500 mmm, more preferably from 500 mm to 1000 mm. The flow guiding elements 112 may be movable, in particular slidable, along the recesses of the first holder 120 and the second holder 122.

[0195] For example, the first holder 120 and the second holder 122 have a width (along the x-axis) from 200 mm to 1500 mm, preferably from 500 mm to 1000 mm, more preferably from 600 m to 800 mm. The first holder 120 and the second holder 122 may have a height (along the y-axis) from 50 mm to 500 mm, preferably from 100 mm to 200 mm.

[0196] For example, a total length of the flow guiding elements 112 may be from 100 mm to 2000 mm, preferably the total length is from 200 to 1500 mm.

[0197] Figure 4 shows a front view onto the support structure arranged at the inlet. Specifically, Figure 4 shows an exemplary connection mechanism, e.g. for connecting the abrasion protection element 110 to a further element, such as a tube sheet 141 of a quench cooler. The abrasion protection element 110 may be mounted to the tube sheet 141 , e.g. via brackets 128. As e.g. shown in Figure 4, the support structure 114 may comprise on each side two elongated holes130 for connecting the support structure 114 to brackets 128. Such a design of holes 130 can allow compensation for thermal expansion between metal of the brackets 128, e.g. an al- loy800H, and the OCMC. Further, a compensation for connection delay can be ensured. The holes 130 and the respective bracket 128 may be clamped via two pins 132, e.g. two ceramic pins. A screw connection, e.g. via a connection tab 134, may be used for connecting the abrasion protection element 110 to the further element.

[0198] Figures 5A to 5C show an embodiment of an abrasion protection element 110 positioned at an inlet and / or within the transfer duct 142 (Figure 5A) and without the transfer duct 142 (Figures 5B and 5C). In the upper part of Figure 5A, a top view on the abrasion protection element 110 positioned at an inlet and / or within the transfer duct 142 is depicted. In the lower part of Figure 5A, a cross sectional view through the sectional axis A-A is depicted. Figures 5B and 5C show the abrasion protection element 110 shown in Figure 5A, but in comparison with Figure 5A without the transfer duct 142. In the upper part of Figure 5B, a top view on the abrasion protection element 110 is depicted. In the lower part of Figure 5B, a cross sectional view through the sectional axis E-E is depicted. In the upper part of Figure 5C a bottom view on the abrasion protection element 110 is depicted. In the lower part of Figure 5C, a cross sectional view through the sectional axis D-D is depicted. In this embodiment, the abrasion protection element 110 comprises three levels of flow guiding elements 112. The levels may be spaced from each other in a direction from an entrance of the abrasion protection element 110 for receiving the particles, e.g. of the gas stream, to an outlet of the abrasion protection element 110. A first end of the support structure 114 may form the entrance of the abrasion protection element 110 and a second, in particular opposing, end may form the outlet of the abrasion protection element 110. For example, the levels may be arranged one after the other in a main flow direction 116. The gas stream in this embodiment flows from bottom to top. The flow guiding element 110 may be positioned at different levels between the entrance of the abrasion protection element 110 and the outlet of the abrasion protection element 110. The levels may be positioned equidistant along the rotational axis or may have different distances between each other. The distances between the levels may be from - 50 mm to 500 mm, preferably from -20 mm to 200 mm, more preferably from 0 to 100 mm. The distance may be measured from a lower edge of the flow guiding element 12 to a point directly below the upper edge of the lower flow guiding element 112.

[0199] The abrasion protection element 110 may be axially symmetric with respect to a rotational axis extending from the entrance to the outlet through a center of the abrasion protection element 110. However, other embodiments, e.g. non-axially symmetric embodiments are feasible. In this embodiment, the flow guiding elements 112 have a disc-like or a plate-like shape. A center of the flow guiding elements 112 may be positioned along the main flow direction 116.

[0200] The support structure 114 may surround the flow guiding elements 112. The support structure 114 may form at least one outer wall or housing of the abrasion protection element 110. The support structure 114 may comprise a single holder, e.g. monolithic, surrounding the flow guiding elements or a plurality of holders forming together the outer wall or housing. The single holder may comprise at least one recess and / or at least one opening.

[0201] The support structure 114 may provide supporting points for the flow guiding elements 112. For example, the support structure 114 may comprise one or more of ribs, recesses, supports, carriers, protrusions and the like for positioning and / or holding the flow guiding elements 112. The support structure 114 may provide for each of the flow guiding elements 112 an identical or a different number of supporting points. For example, the support structure 114 may provide for each of the flow guiding elements 3 to 60 supporting points, preferably 4 to 20, more preferably 4 to 10 supporting points. In the embodiment of Figures 5, the support structure 114 may provide 6 supporting points. The supporting points may form a continuous or non-continuous groove. For example, in case of the flow guiding elements 112 have a circular base, the supporting points may form a supporting ring, e.g. a continuous ring or a non-continuous ring.

[0202] The support structure 114 may comprise a lower holder, e.g. shown in the bottom view of the abrasion protection element 110 in Figure 5C upper part. The lower holder may function in additional as flow guiding element 112. The lower holder may comprise a perforated plate. A center of the lower holder may be closed or covered. This can allow preventing free path of central jets. The lower holder may be positioned as first element at the entrance of the abrasion protection element 110, in particular below (with respect to direction of gravity) the last flow guiding element 112 of the abrasion protection element 110. The lower holder may be configured for securing the flow guiding elements 112 downwards and / or for intercepting detaching parts.

[0203] For example, the support structure 114 may form a cone-shaped abrasion protection element 110. A diameter of the support structure 114 may be tapered, e.g. from the outlet to the entrance. For example, the holder(s) may taper from the outlet to the entrance. For example, a distance between the holders of the support structure may increase from the entrance of the abrasion protection element 110 to the outlet of the abrasion protection element 110.

[0204] Each of the flow guiding elements 112 may comprise a scattering surface. In this embodiment, the scattering surface may be hexagonal.

[0205] A surface area of the scattering surface may be from 10 cm2to 10000 cm2, preferably from 30 cm2to 5000 cm2, more preferably from 50 cm2to 1000 cm2.

[0206] For example, the flow guiding element may comprise a plurality of openings for allowing a flow through the abrasion protection element. The scattering surface may be perforated. An open cross section may be from 5 % to 90 %, preferably from 10 to 80%, more preferably from 20 to 60 %.

[0207] The scattering surfaces may be inclined with respect to the rotational axis. For example, an angle of attack of the flow guiding elements, for both in and against the direction of flow, may be from 5° to 90°, preferably from 10° to 80°.

[0208] For example, the scattering surface may be circular such as a ring or polygonal such as a triangle, a square, or a rectangle. For example, in case of a polygonal scattering surface, the scattering surface may have from 3 to 60 sides, preferably 4 to 20 sides, more preferably from 4 to 10 sides. For example, the scattering surface may be regular or non-regular. For example, the scattering surface may be trapezoidal. For example, the scattering surface may be a parallelogram.

[0209] The flow guiding elements 112 of the different levels may be arranged that projections in main flow direction 116 of two consecutive levels at least partially overlap, e.g. by 0 to 100 %, preferably from 5% to 90 %, more preferably from 10 % to 80 %. List of reference numbers abrasion protection element flow guiding element support structure main flow direction gap first holder second holder recess inner distance bracket holes pins connection tab tube sheet of quench cooler refractory-lined transfer duct from cracker to quench cooler hood of quench cooler

Claims

Claims1 . An abrasion protection element (110) comprising a plurality of flow guiding elements (112), wherein each of the flow guiding elements (112) comprises a core of Oxide Ceramic Matrix Composite, OCMC, and a protective ceramic cover covering of the core; at least one support structure (114) configured for mounting the flow guiding elements (112), wherein the support structure (114) comprises a layered structure comprising at least one layer of OCMC and at least one layer of ceramic.

2. The abrasion protection element (110) according to the preceding claim, wherein the layered structure comprises at least one layer of OCMC and at least one layer of ceramic or a layer of OCMC sandwiched between two layers of ceramic.

3. The abrasion protection element (110) according to any one of the preceding claims, wherein each of the flow guiding elements (112) provides at least one scattering surface for scattering impinging particles.

4. The abrasion protection element (110) according to any one of the preceding claims, wherein the support structure (114) is configured for aligning and / or orienting the flow guiding elements (112).

5. The abrasion protection element (110) according to any one of the preceding claims, wherein the flow guiding elements (112) are aligned and / or oriented such that one or more of the following conditions are fulfilled: a flow cross section of the abrasion protection element (110) is closed; a minimum pressure loss is ensured; flow after passing the abrasion protection element (110) is symmetrical; carbon accumulation is prevented.

6. The abrasion protection element (110) according to any one of the preceding claims, wherein the flow guiding elements (112) and the support structure (114) form a rectangular grid, wherein the support structure (114) comprises a frame comprising a first holder (120) and an opposing second holder (122), wherein each of the first and the second holder (120, 122) comprises a plurality of recesses (124) for receiving the flow guiding elements (112), wherein each recess (124) of the first holder (120) has a corresponding recess (124) in the second holder (122).

7. The abrasion protection element (110) according to the preceding claim, wherein a distance between the first holder (120) and the second holder (124) is adaptable, wherein the first holder (120) and the second holder (122) are movable along the flow guiding elements (112) with respect to each other.

8. The abrasion protection element (110) according to any one of the preceding claims, wherein the flow guiding elements (112) and the support structure (114) form a cone- shaped element, wherein each flow guiding element (112) comprises a circular disc, wherein the circular discs have different cross sections, wherein the support structure (114) comprises a plurality of ribs configured for holding the circular discs.

9. The abrasion protection element (110) according to any one of the preceding claims, wherein the flow guiding elements (112) comprise a geometric body comprising a polygonal or circular base, wherein the flow guiding elements (112) have a conical shape, a tapered shape, a pyramidal shape, or a plate-like shape.

10. The abrasion protection element (110) according to any one of the preceding claims, wherein the protective cover comprises at least one ceramic selected from the group consisting of: AI2O3, SisN i, SiC, B4C.11 . The abrasion protection element (110) according to any one of the preceding claims, wherein the OCMC has a matrix composition selected from the group consisting of: SixMyOz, SixM1yM2wOz, SixByNzCw, AIN, MxOyand mixtures of oxides (M1xOy / M2wOz).The abrasion protection element (110) according to any one of the preceding claims, wherein the OCMC has oxide ceramic reinforcing fibers comprising at least one material selected from the group consisting of: mullite, AI2O3, a combination of mullite and AI2O3.

12. A quench cooler configured for cooling at least one gas stream, comprising at least one outer shell comprising at least one inlet for receiving the gas stream from a furnace and at least one outlet for providing the cooled gas stream; at least one tube bundle comprising a plurality of tubes configured for coolant flow through the tubes, wherein the tube bundle is housed by the outer shell, wherein the tube bundle comprises at least one inlet and at least one outlet for the coolant; at least one abrasion protection element (110) according to any one of the preceding claims, wherein the abrasion protection element (110) is arranged at the inlet for receiving the gas stream from the furnace.

13. The quench cooler according to the preceding claim, wherein the quench cooler comprises at least one tube sheet, wherein the abrasion protection element (110) is mounted to the tube sheet.

14. The quench cooler according to any one of the preceding claims referring to a quench cooler, wherein the gas stream comprises one or more of ethylene, CH4, C2H2, C2H4, C2H6, C3H6, C3H8, C4H6, C4H8, C4H10, C6H6, CO, CO2, H2, H2O, N2, O2.

15. A transfer duct (142) configured for transferring a gas stream from a furnace to a quench cooler, wherein the transfer duct (142) comprises at least one abrasion protection element (110) according to any one of the preceding claims referring to an abrasion protection element (110), wherein the abrasion protection element (110) is arranged at the outlet of the transfer duct (142).

16. A steam cracker comprising at least one quench cooler according to any one of the preceding claims referring to a quench cooler and / or a transfer duct according to any one of the preceding claims referring to a transfer duct, wherein the steam cracker further comprises at least one furnace configured for steam cracking.

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