Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J8/00—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes
  • B01J8/02—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with stationary particles, e.g. in fixed beds
  • B01J8/0242—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with stationary particles, e.g. in fixed beds the fluid flow within the bed being predominantly vertical
  • B01J8/025—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with stationary particles, e.g. in fixed beds the fluid flow within the bed being predominantly vertical in a cylindrical shaped bed
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J35/00—Catalysts, in general, characterised by their form or physical properties
  • B01J35/50—Catalysts, in general, characterised by their form or physical properties characterised by their shape or configuration
  • B01J35/56—Foraminous structures having flow-through passages or channels, e.g. grids or three-dimensional monoliths
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J8/00—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes
  • B01J8/008—Details of the reactor or of the particulate material; Processes to increase or to retard the rate of reaction
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J8/00—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes
  • B01J8/008—Details of the reactor or of the particulate material; Processes to increase or to retard the rate of reaction
  • B01J8/0085—Details of the reactor or of the particulate material; Processes to increase or to retard the rate of reaction promoting uninterrupted fluid flow, e.g. by filtering out particles in front of the catalyst layer
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J8/00—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes
  • B01J8/008—Details of the reactor or of the particulate material; Processes to increase or to retard the rate of reaction
  • B01J8/009—Membranes, e.g. feeding or removing reactants or products to or from the catalyst bed through a membrane
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J8/00—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes
  • B01J8/02—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with stationary particles, e.g. in fixed beds
  • B01J8/0242—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with stationary particles, e.g. in fixed beds the fluid flow within the bed being predominantly vertical
  • B01J8/0257—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with stationary particles, e.g. in fixed beds the fluid flow within the bed being predominantly vertical in a cylindrical annular shaped bed
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J8/00—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes
  • B01J8/02—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with stationary particles, e.g. in fixed beds
  • B01J8/0278—Feeding reactive fluids
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J8/00—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes
  • B01J8/02—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with stationary particles, e.g. in fixed beds
  • B01J8/0292—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with stationary particles, e.g. in fixed beds with stationary packing material in the bed, e.g. bricks, wire rings, baffles
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J2208/00—Processes carried out in the presence of solid particles; Reactors therefor
  • B01J2208/00796—Details of the reactor or of the particulate material
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J2208/00—Processes carried out in the presence of solid particles; Reactors therefor
  • B01J2208/00796—Details of the reactor or of the particulate material
  • B01J2208/00823—Mixing elements
  • B01J2208/00831—Stationary elements
  • B01J2208/00849—Stationary elements outside the bed, e.g. baffles
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J2208/00—Processes carried out in the presence of solid particles; Reactors therefor
  • B01J2208/00796—Details of the reactor or of the particulate material
  • B01J2208/00884—Means for supporting the bed of particles, e.g. grids, bars, perforated plates
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J2219/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
  • B01J2219/02—Apparatus characterised by their chemically-resistant properties
  • B01J2219/0204—Apparatus characterised by their chemically-resistant properties comprising coatings on the surfaces in direct contact with the reactive components
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J2219/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
  • B01J2219/32—Details relating to packing elements in the form of grids or built-up elements for forming a unit of module inside the apparatus for mass or heat transfer
  • B01J2219/322—Basic shape of the elements
  • B01J2219/32286—Grids or lattices
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J2219/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
  • B01J2219/32—Details relating to packing elements in the form of grids or built-up elements for forming a unit of module inside the apparatus for mass or heat transfer
  • B01J2219/324—Composition or microstructure of the elements
  • B01J2219/32408—Metal
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J2219/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
  • B01J2219/32—Details relating to packing elements in the form of grids or built-up elements for forming a unit of module inside the apparatus for mass or heat transfer
  • B01J2219/324—Composition or microstructure of the elements
  • B01J2219/32466—Composition or microstructure of the elements comprising catalytically active material
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T29/00—Metal working
  • Y10T29/49—Method of mechanical manufacture
  • Y10T29/49826—Assembling or joining

Definitions

• the invention relates to a fixing device for catalyst particles, wherein the catalyst particles are present in a bed, which is formed by a gas flow in the direction of gravity flow-through.
• Catalysts for example in reactors for gas-phase reactions, may be present in the form of particles in a fixed-bed flow, through which the gas flow in the gravitational direction flows.
• it is necessary to fix the particles in order to avoid unwanted particle movements since such movements can cause signs of wear in the form of abrasion or loss due to fragmentation of the particles into smaller fragments. This can result in an increased pressure loss in the catalyst bed or the particle fractions discharged with the gas stream can have undesirable effects in downstream system parts.
• the problem may be compounded in gas phase reactions, such as propane or butane dehydrogenation, where a process gas and a reaction gas must be mixed before entering the catalyst bed.
• gas phase reactions such as propane or butane dehydrogenation
• a process gas and a reaction gas must be mixed before entering the catalyst bed.
• the volume smaller gas stream is injected into the other gas stream at high speed, often only a very short residence time ( ⁇ 100 ms) of the gas mixture in the free space before entering the catalyst bed may be tolerated.
• This requires in addition to high flow rates, a small distance of the mixing nozzles from the catalyst surface.
• a layer of very large particles, usually inert for the desired reaction is applied to the catalyst bed.
• This can also be comparatively large ceramic balls, which, just like the large particles, fix the underlying bed of very small catalyst particles.
• the problem here is, in particular in the above-described method, in which a short residence time of the gas mixture in the free space before the catalyst bed is necessary that the residence time of the gas mixture before entering the catalyst layer is increased increases to the flow through the ball bed. Since local channels and free spaces inhibit a further gas mixture within the ball bed, the optimum mixing must already be completed above the balls, so that the flow through the balls only increases the residence time, but does not serve as a mixing section.
• the object of the invention is to provide a fixing device for catalyst particles, in particular in flow-through in the direction of gravity fixed bed, which avoids the disadvantages listed above and in particular has a low specific pressure loss, which remains low even with possible operational contamination, as little influence the residence time of the gas flowing through has made possible a secure holddown of the catalyst particles even at high flow velocities and has a certain flexibility in order to be able to adapt to changes in the bedrock.
• the invention achieves this by means of a fixing device for catalyst particles having the features of patent claim 1.
• the fixing device according to the invention is on the bed of the catalyst particles, for example in a reactor, as described in DE 103 59 744 Al the Applicant, a layer of metal mesh placed, which consists of individual firmly intertwined metal mesh elements. The weight of this metal mesh, the particles are held down. By tilting the uppermost particle layer within the metal Braided also prevents a transverse movement of the particles.
• the thickness of the metal braid is relatively small, so that the time required for the gas to flow before flowing into the catalyst layer is extremely short. Due to a favorable ratio of its metal mesh cross section to the material thickness of the pressure loss is low. Furthermore, the metal braid is flexible, so that a sagging of the catalyst bed does not cause the bottom of the metal mesh loses contact with the surface of the catalyst particles, so that in this case, a secure fixation, as described above, is maintained.
• the metal mesh is formed such that the maximum possible free cross section of a metal mesh element is smaller than the smallest cross section of the catalyst particles. This prevents that catalyst particles can be swirled up through the metal mesh and destroyed. Also, the described canting effect is achieved in a particularly advantageous manner, so that a secure fixation of the particles is ensured even at high flow velocities of the gas flowing through.
• the individual metal mesh elements have a closed shape.
• a metal mesh of self-contained metal mesh elements offers a particularly advantageous ratio of flexibility compared to its own weight, which has a positive effect on the function of the fixing device.
• the metal mesh elements are oval and / or annular. The interweaving of annular elements can have manufacturing advantages. But it is also possible that the elements are formed oval or have a different shape, which may be preferable depending on the application under circumstances.
• each of the metal mesh elements is formed firmly closed and / or welded.
• a metal mesh of rings is conceivable, which are only compressed, but in this case the achievable strengths are often not sufficient, so that in conventional applications, a permanent closure of the rings or their welding is preferable.
• the areal size of the metal mesh is greater than the surface area of the bed of catalyst particles. In this way, a tension in the metal mesh is avoided when resting the metal mesh on the catalyst bed. Due to the loosely resting on the metal mesh can yield to the sagging of the bed and so continue to have full contact with the surface of the bed. Possible local unevennesses of the bed surface are easily compensated by the loosening of the metal mesh.
• the areal size of the metal mesh is 1.05 to 2 times the size of the surface of the bed of catalyst particles. These values for the size of the metal mesh compared to the surface of the catalyst bed have proven to be particularly advantageous.
• At least one further layer of a metal mesh can also be advantageous for at least one further layer of a metal mesh to rest on the first layer of the metal mesh.
• braid feels like.
• a very fine-mesh metal mesh must be used, by applying a further layer of metal mesh, the pressure forces and thus the fixing effect of the lowest layer of the metal mesh can be significantly increased become.
• the mesh size of the metal braids lying above does not have to correspond to the mesh width of the lowest metal braid. It can be advantageous that the maximum possible free cross-section of the further layers of the metal braid next to the same size is also larger and / or smaller than the maximum possible free cross section of the first layer of the metal braid.
• the pressure effect can be increased by applying an additional weight by a second or further layers of a coarser metal braid, wherein the fixing is performed by the bottom metal mesh layer having a small free cross section for fixing the particles.
• At least one laid-up layer of the metal mesh may consist of a plurality of interconnected segments.
• the segments may be connected to each other at the seams substantially to shock or himself partially overlap at the seams. This depends on the design of the reactor and other parameters resulting from the specific requirements.
• the metal mesh consists of a catalytically active material and / or is coated with a catalytically active material.
• the effective residence time of the gas stream above the catalyst bed can be further reduced.
• the metal mesh consists of a corrosion-resistant material and / or is provided with a corrosion protection. This also depends on the application, in particular the reaction gases and catalyst materials used, possibly useful to reduce the wear of the metal mesh during operation.
• the fixing device is designed for use in an oxy-reactor for dehydrogenation of butane and / or propane.
• the invention has proven to be particularly effective.
• the invention also relates to a method for holding down catalyst particles with a fixing device, as described above, with the features of claim 15, and a reactor for gas phase reactions with the features of claim 16.
• FIG. 2 is a schematic plan view of an inventive metal braid in a stretched state
• Fig. 3 shows an example of a metal mesh according to the invention in the laid, unstressed state and in
• Fig. 4 is a schematic representation of a single member of a metal mesh according to the invention.
• gas phase reactor has a gas inlet tube 2, which passes through a horizontally disposed catalyst 3 centrally, wherein above the catalyst bed in the reactor, a gas 4 is formed.
• the centric gas inlet tube 2 is surrounded by a ring manifold 5 for oxygen in pure form, as air or mixed with inert gas or water vapor, said annular tube 5 feeds a plurality of equipped with outlet openings 6 annular tubes 7, which are arranged above the catalyst 3.
• the O 2 inlet into the annular distributor 5 is indicated only by arrows 8, and the gas outlet of the reactor is only indicated and bears the reference 9. Below the free space in which the two gases mix with each other, there is a position of a Metal braid 10 according to the invention.
• the metal mesh 10 is larger in area than the size of the surface of the catalyst bed 3, so that it rests loosely on the bed 3 and compensates for local unevenness. Upon yielding of the bed 3, it is further terhin over the entire surface on the surface.
• On the first layer of the metal braid 10 is another layer of a metal mesh 10a according to the invention, which has larger metal mesh elements 11, as the first layer of the metal mesh, in which the free cross-section is smaller than the smallest size of the particles in the catalyst particle bed.
• FIG. 2 A plan view of a metal mesh 10 according to the invention is shown in greater detail in FIG. 2 and FIG. 3, wherein in FIG. 2 the metal mesh is shown in a tensioned state. It is the metal mesh layer, which rests directly on the particle bed, in which the free cross sections of the openings in the metal mesh are chosen so that they are smaller in the tensioned state than the smallest occurring in the catalyst bed particle size.
• an embodiment of the metal mesh 10 according to the invention consists of round, self-contained annular metal mesh elements 11, which are welded at their connection point, so that they do not bend even with tensile loads. Furthermore, it can be seen that the diameter of the metal mesh rings is not inevitably must be smaller than the smallest particle size, since depending on the ring thickness of the smallest free cross section is less than the radius opening of a single ring element.
• the invention is not limited to the above embodiment, but can be modified in many ways, without departing from the spirit, in particular the materials of the metal mesh of the catalyst particles and the gases used for the flow, gas mixtures u. like. are adapted to be selected for the different applications and covered by the invention, the same applies to the design of the metal mesh itself, as long as it has the claimed properties.

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• Chemical & Material Sciences (AREA)
• Organic Chemistry (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Physics & Mathematics (AREA)
• Fluid Mechanics (AREA)
• Engineering & Computer Science (AREA)
• Materials Engineering (AREA)
• Devices And Processes Conducted In The Presence Of Fluids And Solid Particles (AREA)
• Physical Or Chemical Processes And Apparatus (AREA)
• Catalysts (AREA)
• Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
• Braiding, Manufacturing Of Bobbin-Net Or Lace, And Manufacturing Of Nets By Knotting (AREA)

Applications Claiming Priority (2)

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Citations (3)

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• 2008
  • 2008-02-21 DE DE102008010422A patent/DE102008010422A1/de not_active Ceased
• 2009
  • 2009-01-23 US US12/735,840 patent/US8303904B2/en not_active Expired - Fee Related
  • 2009-01-23 WO PCT/EP2009/000405 patent/WO2009103395A1/de not_active Ceased
  • 2009-01-23 MX MX2010009249A patent/MX339868B/es active IP Right Grant
  • 2009-01-23 KR KR1020107014320A patent/KR101590200B1/ko not_active Expired - Fee Related
  • 2009-01-23 EA EA201001314A patent/EA019310B1/ru not_active IP Right Cessation
  • 2009-01-23 JP JP2010547072A patent/JP5727230B2/ja not_active Expired - Fee Related
  • 2009-01-23 EP EP09712941A patent/EP2252392A1/de not_active Withdrawn
  • 2009-01-23 BR BRPI0907582-8A patent/BRPI0907582A2/pt active Search and Examination
  • 2009-01-23 MY MYPI20103147 patent/MY150513A/en unknown
  • 2009-01-23 CA CA2715801A patent/CA2715801C/en not_active Expired - Fee Related
  • 2009-01-23 CN CN200980101638.1A patent/CN101909739B/zh not_active Expired - Fee Related
  • 2009-02-20 AR ARP090100587A patent/AR070448A1/es unknown
• 2010
  • 2010-09-20 ZA ZA2010/06716A patent/ZA201006716B/en unknown

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