JP4768726B2 - Method for structurally filling contact tubes of a contact tube bundle - Google Patents

Description

  The present invention relates to a method for structurally filling the contact tubes of a contact tube bundle, in which the individual contact tubes of the contact tube bundle are filled in a uniform manner from bottom to top with a composition which can be distinguished from one another stepwise.

  In many cases of tube bundle reactors (reactors having a bundle of contact tubes contained in a reaction vessel), a method for carrying out a heterogeneous contact gas phase reaction by contacting a catalyst fixed bed existing in a vertically arranged tube The tube bundle reactors necessary for this are known as well (see, for example, German Patent No. 4431949, European Patent No. 7000071). These may be endothermic gas phase reactions or exothermic gas phase reactions. In both cases, the reaction mixture is passed through a fixed catalyst bed present in a so-called contact tube of a tube bundle reactor, and the reactants react partially or completely during the time that the reactants stay on the catalyst surface. The reaction temperature in the contact tube is such that the liquid heat medium (heat exchange means) passes around the contact tube of the tube bundle contained in the container in order to introduce energy into the reactor or to remove energy from the reactor. Adjusted by. In this case, the heating medium and the reaction gas mixture can pass through the tube bundle reactor in the forward or countercurrent manner.

  In this case, in addition to the possibility of supplying the heat exchange means in a simple manner substantially longitudinally directly to the contact tube, this longitudinal feed can be realized throughout the reaction vessel or by means of a continuous deflection plate. This longitudinal flow can be superposed inside the reaction vessel, the deflector plate leaving the cross section and being arranged along the contact tube, resulting in a meandering flow of the heat medium in the longitudinal section of the tube bundle (eg Germany) No. 4,431,949, European Patent No. 7,00714, German Patent No. 2,830,765, German Patent No. 2,201,528, German Patent No. 2231557 and German Patent No. 2310517).

  If necessary, heat media that are substantially separated from one another in space can be passed around the contact tube and into tube sections arranged at various positions along the tube. The tube portion through which a particular heat medium extends generally represents a separation reaction zone. One advantageous variant of this multi-zone tube bundle reactor is for example German Patent No. 2830765, German Patent No. 2513405, US Pat. No. 3,147,084, German Patent No. 2121528, European Patent No. 383224, and German Patent No. 2903582. 2 zone tube bundle reactor.

  Suitable heat media are, for example, molten salts of salts such as potassium nitrate, potassium nitrite, sodium nitrite and / or sodium nitrate, low melting metals such as alloys of sodium, mercury and various metals, ionic liquids (at least one kind of Oppositely charged ions are ionic liquids having at least one carbon atom), but common liquids such as water or high-boiling organic solvents (eg mixtures of Diphyl and dimethyl phthalate) are also applicable.

  Contact tubes are generally formed from ferritic or stainless steel and often have a wall thickness of a few mm, for example 1 to 3 mm. Its diameter is generally a few centimeters, for example 10-50 mm, often 20-30 mm. The length of the tube is usually in the range of a few meters (contact tube length is typically 1-8 m, often 2-6 m, often 2-4 m). The number of contact tubes (work tubes) accommodated in the container is preferably at least 1000, often at least 3000 or 5000, often at least 10,000, from a work point of view. The number of contact tubes contained in the reactor vessel is often 15000-30000 or 40000 or 50000. Tube bundle reactors with more than 50000 contact tubes tend to be eliminated. The contact tubes are usually distributed substantially evenly in the container, advantageously such that the distance between the central inner axes of the nearest adjacent contact tubes (contact tube distance) is 25-55 mm, often 35-45 mm. Distributed (see for example EP 468290).

  In general, at least some of the contact tubes (work tubes) of the tube bundle reactor are advantageously uniform over the entire length (within the limits of production accuracy), ie from the point of view of operation, i.e. their inner diameter, wall thickness and length. Same within narrow tolerances (see WO 03/059857).

  Said necessary properties often correspond to the filling of the catalyst compacts into uniformly manufactured contact tubes in order to ensure optimal and substantially problem-free operation of the tube bundle reactor (eg WO 03/057653). Issue). In order to achieve an optimum yield and selectivity of the reaction carried out in particular in the tube bundle reactor, it is important that all working tubes of the reactor are advantageously packed as uniformly as possible in the catalyst bed.

  A distinction is made between working tubes and the thermotubes described, for example, in EP 837783. The working tube is a contact tube that actually performs the chemical reaction to be performed, but the thermo tube is first used to monitor and adjust the reaction temperature in the contact tube. For this purpose, the thermopipe generally has a fixed thermocouple cover in addition to the fixed bed of the catalyst, the cover being provided only with a temperature sensor, and traveling vertically through the thermopipe. In general, the number of thermo tubes in the tube bundle reactor is much smaller than the number of working tubes. The number of thermo tubes is generally 20 or less.

  This applies in particular to the heterogeneous catalytic gas phase partial oxidation of at least one organic compound, which takes place in a tube bundle reactor during which a considerable amount of heat is released.

  Examples which may be mentioned are the conversion of propene to acrolein and / or acrylic acid (see, for example, German Patent 2,351,151), t-butanol, isobutene, isobutane, isobutyraldehyde, or methacrolein and / or methacrylic of methyl ether of t-butanol Conversion to acid (see, for example, German Patent No. 2526238, European Patent No. 92097, European Patent No. 58927, German Patent No. 4132263, German Patent No. 4132684, and German Patent No. 4022212), acrolein to acrylic acid Conversion of methacrolein to methacrylic acid (eg German Patent No. 2526238), conversion of o-xylene or naphthalene to phthalic anhydride (see eg German Patent No. 522871) and butadiene Conversion to hydromaleic acid (for example German Patent No. 2106796 and German Patent No. 1624921), conversion of n-butane to maleic anhydride (for example British Patent No. 1464198 and British Patent No. 1292354), Indan for example anthraquinone Conversion (e.g. German Patent No. 2025430), conversion of ethylene to ethylene oxide or propylene to propylene oxide (e.g. German Patent 1254137, German Patent 2159346, European Patent 372972, WO89 / 0710, DE 4311608), conversion of propylene and / or acrolein to acrylonitrile (eg German Patent 2351151), conversion of isobutene and / or methacrolein to methacrylonitrile. (Ie the term partial oxidation for the purposes of the present invention includes partial ammoxidation, ie partial oxidation in the presence of ammonia), dehydrogenation by oxidation of hydrocarbons (eg German Patent 2,351,151), Conversion to acrylonitrile or acrolein and / or acrylic acid (eg German Patent No. 101031297, European Patent No. 1090684, European Patent No. 608838, German Patent No. 10046672, European Patent No. 529853, WO 01/96270 and German Patents) No. 10028582).

  Catalysts used to carry out heterogeneous catalytic gas phase reactions on a fixed bed of catalysts located in tube bundle reactors and tubular reactors are generally active materials that can be shaped to produce shaped bodies of various shapes. Yes (called a catalyst compact). Examples of these shaped bodies are spheres, pellets, extrudates, rings, spirals, pyramids, cylinders, prisms, cubes, cubes and the like.

  In the simplest case, the shaped body consists only of catalytically active material, which may optionally be diluted with an inert material. These shaped bodies are generally called fully active catalysts.

  In the case of a fully active catalyst, the shaping can be performed, for example, by compressing a catalytically active powder (eg a powdered active multicomponent oxide composition) to produce the desired catalyst shape (eg tableting, sintering, screw extrusion or ram extrusion). )).

  Alternatively, molding can be achieved by coating a catalyst inert material (inert material) with an active material. As with all active catalyst compacts, the inert support can have a regular or irregular shape. In the simplest case, for example, the surface of an inert carrier is moistened using a liquid binder, followed by application of the powdered active material to the moistened surface, and the binder is applied to the surface for coating. be able to. The resulting catalyst is called a coated catalyst.

  Inert supports suitable for many heterogeneous catalytic gas phase reactions are porous or non-porous aluminum oxide, silicon dioxide, thorium dioxide, zirconium dioxide, silicon carbide or silicates such as magnesium silicate or aluminum silicate (eg of type C220 CeramTec). Steatite) and metals such as stainless steel or aluminum.

  Geometrically inert (in the context of the present invention, inertness is generally less than 5 mol% of the reactant conversion rate when the reaction gas mixture passes through a packing containing only dilute shaped bodies under the reaction conditions. Instead of coating the support with the active material (which generally means less than 2 mol%), the support can often be impregnated with a solution of the catalytically active substance and subsequently evaporate the solvent. The catalyst compact resulting from this process is commonly referred to as a supported or impregnated catalyst.

  The longest diameter of the catalyst compact (the longest possible direct contact line between two points on the surface of the catalyst compact) is generally 1-20 mm, often 2-15 mm, often 3 or 4-10 or 8 or 6 mm. In the case of rings, the wall thickness is generally 0.5 to 6 mm, often 1 to 4 or 3 or 2 mm.

  The active materials used are particularly often noble metals (eg Ag) or oxide materials containing oxides together with one or more other elements (multi-element oxide materials, eg multi-metal oxide materials) It is.

  Only in very few heterogeneous catalytic gas phase reactions on the fixed bed of catalyst present in the tubes of the tube bundle reactor, the fixed bed of the catalyst is uniform along the individual contact tubes and the catalyst compact that completely fills the contact tubes. It consists of one floor.

  Rather, in most cases, the contact tube packing consists of multiple portions of catalyst packing disposed on top of each other. Each individual bed portion consists of a uniform bed of catalyst compacts. However, its composition generally changes suddenly as it moves from one floor part to the next. This is also referred to as a structured packing (or bed) in the contact tube.

  Examples of structured packing in these contact tubes are in particular European Patent No. 979813, European Patent No. 90074, European Patent No. 456837, European Patent No. 1105598, US Pat. No. 5,1985,811 and US Pat. No. 4203903.

  In the simplest case, two different parts of the catalyst packing in the reaction tube were diluted with different proportions of inert compacts with no active material, with the catalyst compact having one active material ( In the simplest case, known as a diluted shaped body, it may be an inert carrier, but it may also be a shaped body formed from metal. This diluted shaped body can have the same shape as the catalyst shaped body or a different shape (the longest possible dimension range is generally governed by the same limits as for the catalyst shaped body). Many types of dilute shapes by arranging portions of catalyst packing with different degrees of dilute, which are individually adapted to the requirements of the gas phase reaction carried out in each case, continuously along the contact tube (Diluted structure) can be manufactured. In many cases, the lean structure decreases the degree of dilution in the flow direction of the reaction gas mixture (ie, the specific volume active material increases in the flow direction and the specific volume activity is low where the reactant concentration is high, and vice versa. Is also the same). However, if necessary, the opposite or completely different dilute shapes (active structuring) can be selected. In the simplest case, the structured packing in the contact tube is a portion of the catalyst packing consisting of a catalyst shaped body with an active material (which may be diluted with a dilute shaped body), for example at the bottom of the contact tube. There is a portion of the catalyst filling consisting only of the lean shaped body (the portion of the filling consisting of only the lean shaped body is hereinafter referred to as the portion of the packing consisting of the catalyst shaped body). May be. It is also possible to interrupt the two parts of the packing formed from the same catalyst shaped body with active material by the part consisting only of the lean shaped body.

  Of course, the active structuring can also be caused by a mixture that does not change along two or more different parts of the catalyst body with the active material present in the part of the packing in the contact tube. In this case, the catalyst shaped bodies differ only in shape or only in the chemical composition of the active material or in the physical composition of the active material (eg pore distribution, specific surface area, etc.) Only the mass ratio of the active material applied may be different. However, the catalyst molded body may be different in two or more or all of the different features. Furthermore, the catalyst molded body can include a diluted catalyst molded body. Instead of active structuring, the filling of the contact tube may have selective structuring. Selective structuring occurs particularly as a reaction followed by a gas phase reaction, and is particularly advantageous when the individual active materials can catalyze various subsequent reaction steps in a demanding manner.

  Overall, in the case of a structured packing in the part in the contact tube (from bottom to top), the uniformly packed part in the reaction tube consists of only one type of catalyst or only one type Catalyst moldings of a specific composition, which may consist only of a dilute molding, or a mixture of catalyst moldings, or a mixture of a catalyst molding and a dilute molding, or may be a mixture of various lean moldings Represents.

  Contact tubes filled in a structured manner have by definition at least 2, often 3 or 4, often 5 or 6, or 7 or 8 to 10 or more portions of filling Are different in terms of their type and / or amount, i.e. generally not the same.

  Uniform filling of the contact tubes filled in this structured manner only requires that the same composition of the catalyst compact that does not vary along the contact tube portion is present in the corresponding contact tube portion. It is. Secondly, however, it is necessary that the same amount of the same composition of the catalyst compact is present in the corresponding contact tube section.

  In order to achieve this purpose in the case of a large number (more than 10,000) of contact tubes (working tubes), a measured portion of each composition of the catalyst compact is introduced into each contact tube from a storage container with the composition. State-of-the-art catalyst filling equipment was used (see, for example, German Patent No. 19934324, WO 98/14392 and US Pat. No. 4,402,463). The main type of parameter sought here is the uniform rate of introduction (ie a very constant amount of each catalyst compact composition introduced per unit time during filling). The dimensions of the portion into which the composition having an introduction rate and introduction time is introduced and the portion to be filled are determined.

  However, state-of-the-art methods have various drawbacks. First, the rate of introduction is not completely constant over time, resulting in a shift in the introduced portion. This is particularly due to the fact that the molded body to be introduced is arranged laterally and occasionally closes the molded body outlet of the filling device. If the individual composition of the catalyst shaped body consists of more than one type of shaped body, partial demixing occurs in the storage vessel, which is ultimately compared to the portion of the corresponding packing in the various contact tubes. Cause some compositional variation. Within one and the same part of the packing in the individual contact tubes, composition variations occur along the part of the packing. Furthermore, the packing speed achieved is often not sufficient. The rate of packing is particularly important since the production, ie the gas phase reaction, is interrupted during the filling of the contact tube.

  It is therefore an object of the present invention to provide an improved method of filling contact tubes in a bundle of contact tubes in a structured manner.

  A method for filling the contact tubes of a bundle of contact tubes in a structured way, filling the individual contact tubes of a bundle of contact tubes in a uniform manner from bottom to top in cross-section with different compositions of the catalyst compact. First, a uniform portion of a suitable composition of the catalyst molded body is formed, and the portion is surrounded by a packaging material to produce a package filled with a uniform amount of the composition of the catalyst molded body. It is characterized in that a specific part of the filling in the contact tube is produced by transferring the packet to each individual contact tube. This number of packets transferred to one contact tube is generally 1 or more.

  According to the invention, the uniformity interval of said parts is generally less than ± 1% by weight or less than 0.3% by weight or less than 0.1% by weight (based on the number average of all uniformly produced parts) Is less than 0.01% by weight. The smaller the relative uniformity interval, the larger the portion present in the packet.

  The method of the present invention is generally applicable to catalyst shaped bodies in which the longest diameter L is (substantially) smaller than the inner diameter D of the reaction tube. However, a diameter as large as this diameter is also common. The D / L ratio is often 2: 1 or 3: 1 to 20: 1 or 4: 1 to 10: 1.

  The amount present in the packet filled with the catalyst compact is preferably between 50 g and 5 kg, adapted to the desired length of the part of the packing and determined in advance by injection tests in a suitably shaped transparent tube. . The amount of one part is often 100 g to 3 kg, often 200 g or 300 g to 2 kg, i.e. the amount may be eg 400 g, 600 g, 800 g, 1000 g, 1200 g, 1400 g, 1600 g and 1800 g. This generally corresponds to a numerically similar packing volume in l or ml (ie in the range of 25 or 50 ml to 5 or 10 l).

  According to the present invention, the amount of wrap is very advantageously the amount that, when transferred to the reaction tube, produces all the desired parts of the packing in the tube. However, in order to achieve an increased uniformity of the filling part, the amount corresponding to one part is a packet in which the production of the desired part of the filling is transferred more than one (often 2-10, often 2-5). The required amount may be used.

  The packaging may be paper bags, bags made from other materials, large bags, boxes, cans, compartments, buckets, frame boxes, baskets, drums, bottles and the like. Depending on the active material, paper, cardboard, wood, glass, ceramic materials, metals (sheets and foils), plastics, foams, etc. can be used as packaging materials. The choice of packaging means and packaging method depends not only on the type of active material, but also on the type of external influence expected after packaging, for example during storage. For example, heat resistance, impact stability, light impermeability, air impermeability, water vapor impermeability and the like are required.

  For example, it is advantageous to package the part using a shrinkable film that can be sealed under reduced pressure and that can be easily laminated. For example, the packaging material may discharge foreign substances such as volatile plasticizers or residual monomers, be present during storage of the package, and clog the catalytically active surface so that the packaging material does not adversely affect the properties of the catalyst. General care must be taken to ensure.

According to the invention, transparent polyethylene (high density, low density or medium density) is a particularly advantageous packaging material, especially when the active material is a multi-element oxide, such as a multi-metal oxide. The moisture (water vapor) permeability of the package which is 1.0 g / m ² / d ¹ (d = day) or less at 25 ° C. is generally advantageous. For this purpose, for example, an aluminum-coated bag or a bag made of liquid crystal polyester film can be used. An advantageous means is a bag, especially if it is made of plastic (for example polyethylene) and can be sealed by airtight welding.

A uniform amount of the composition of the catalyst compact is filled, and the production of the packets used according to the invention can be carried out very efficiently and at high speed by means of a packaging device prior to the corresponding filling process. Dispensing devices are particularly advantageous for the method of the invention. In the case of this packaging device combination, the packaged goods exist in a form produced for distribution (for example, packaging apparatuses that produce the packaged goods themselves from films prepared in the form of rolls are frequently used. Though). As a basic component, the packaging device is a dispensing device that distributes the material to be filled according to the mass or number of parts, a device that actually fills and, for example, twist, rotate, fold, adhere and join, weld, Consisting of a closing device that closes the package from loose to firm by the groove / spring principle or by attachment with fasteners, if the composition of the catalyst molded body introduced by the present invention has more than one type of molded body, the composition The production according to the invention of a uniform part of an object is preferably carried out as follows.

  First, each type of compact is produced in large quantities with as much uniformity as possible.

  Subsequently, a uniform part of each type of molded body is continuously produced by means of a metering device prepared for each type of molded body according to the mass or number of parts. Put it in the prepared conveyor belt. Each conveyor belt conveys a uniform portion of each type of compact at an appropriate speed. The conveyor belts come together at their ends and discharge the desired amount of each type of molded body into a wrap. This produces a packet whose contents are indistinguishable in terms of quantity and composition.

  Filling the contact tube is a simple way to transfer the number of packets pre-calculated from the dimensions of the contact tube and the desired length of the packing part and measured in the injection test in the correspondingly shaped transparent reaction tube. The packet filled with the composition of the catalyst molded body can be transferred to each contact tube. In the method of the invention, the amount packaged in the individual packet is always less than or equal to the amount introduced into the individual contact tubes. Often there is a case where the same number of packets is transferred to each contact tube. The number transferred to the contact tube according to the invention is preferably an integer. Since each packet provided for the filling part has the same composition and amount, a filling part that is particularly uniform on various contact tubes can thus be produced in a short time according to the invention.

  The easiest way to transfer the packet to the contact tube is by hand. However, in order to transfer the packet to the contact tube so as to obtain a very uniform bulk density, the movement can also be carried out by means of an apparatus for filling the tube with the bulk material described in DE 199334324. This device has a certain number of distribution pipes, which can be lowered simultaneously into the contact tubes to be filled. This device has one storage container per distribution pipe, which is connected to each distribution pipe by an inlet and a conveying chute. Due to the individual operable metering zones, the flow of the loose mass discharged from the respective storage container to the conveying chute is limited to the desired speed to be introduced into the contact tube. Instead of transferring the packet filled according to the invention directly to the respective contact tube, the package is consumed continuously by each storage container of the filling device (the capacity of the storage container is preferably the content of one packet or 1 or It can be transferred to each contact tube (corresponding to the content of two packets) with a very uniform transport speed. Since the storage container does not contain a large amount of the composition of the catalyst compact that is filled at any time, this naturally prevents demixing of the compact in the storage container and the stability of the introduction rate is very uniform. Produces density. A typical conveying speed may be from 500 molded bodies per minute to 40000 molded bodies per minute.

  A particularly advantageous filling device has a cascade of storage vessels that are connected to one another and substantially allow continuous execution of the process of the invention.

  There is a second storage container on top of each storage container in this arrangement, and this container fills the portion corresponding to one packet before the contents of the underlying storage container are completely discharged. Can do.

  Storage containers arranged on top of each other can be connected to various distribution pipes.

  The process according to the invention can be carried out, for example, when the active material of the catalyst compact present in the package is a multi-metal oxide containing Mo, Bi and FE (for example the oxide of the general formula II of DE 44 42 346) and / or Mo and It is suitable when it is a multimetal oxide containing V (for example, an oxide of the general formula I of German Patent No. 4442346). However, the active material of the catalyst compact present in the wrapping is a multimetallic oxide containing V and P (eg for the production of European Patent No. 302509, eg maleic anhydride) or a multimetallic oxidation containing V and Cs Products (for example EP 1084115, EP 1117484, or EP 131467, for example for the production of phthalic anhydride) or Mo and P-containing multimetal oxides (for example DE 4329907) For example, for the production of methacrylic acid).

  The methods recommended in connection with the present invention are the publications for the heterogeneous catalytic partial oxidation of propene and / or acrolein to acrylic acid, European Patent No. 7000893, European Patent No. 7000071, German Patent No. 10337788, German Patent No. Structured contact tube fillings recommended in US Pat. No. 10313210, German Patent No. 10313214, German Patent No. 10313213, German Patent No. 10313212, German Patent No. 10313211, German Patent No. 10313208, German Patent No. 10313209 It is particularly useful for filling parts of the contact tube. The packaging material used should be a packaging material that is highly permeable to water vapor and closed in an airtight manner. The recommendation of Japanese Patent Laid-Open No. 15-10695 can pursue this purpose. If necessary, the filling aids recommended in German Patent No. 10337998 can be used. This corresponds to the filling means recommended in the state of the art cited within the scope of the present invention.

  The method of the present invention is superior with respect to the high degree of packing uniformity that can be achieved using the method of the present invention and for high filling rates combined with the same packing uniformity that can be achieved using the method of the present invention. Yes. Both depend to a great extent on the fact that the distribution and filling of the parts are separated from each other in space and time. The length of the uniform portion of the packing when using the method of the present invention is typically 20 cm to 800 cm, often 50 cm to 200 cm.

  According to the invention, it is particularly advantageous to provide a packet containing the same composition of a shaped catalyst body having a specific color. After transferring the packets to the individual reaction tubes to produce the desired part of the packing, each reaction tube can subsequently be closed with a cap of the same color to advantageously indicate that this process has been completed. . This constitutes a very simple way of avoiding that the reaction tube is filled more than once with one and the same composition of the catalyst compact. Alternatively, the filling height of the reaction tube can be checked with a measuring bar.

Examples and Comparative Examples A) Using the method described in Example 1 of German Patent No. 10046957, 70 kg of a fully active catalyst ring having a shape of 5 mm × 3 mm × 2 mm (outer diameter × length × inner diameter) is produced. did.

The stoichiometry of the active material was as follows:
[B ₂ W ₂ O ₉ × 2WO ₃ ] _0.5 × [Mo ₁₂ Co _5.5 Fe _2.94 Si _1.59 K _0.08 O _x ] ₁
70 kg of fully active catalyst ring is uniformly mixed with 30 kg of steatite ring having a shape of 7 mm × 7 mm × 4 mm, and the catalyst filling described in German Patent No. 1934324 is carried out in a transparent plastic tube having an inner diameter of 35 mm and a length of 6 m The apparatus was used to fill the mixture until the plastic tube was completely filled. In this filling method, all homogeneous mixture was placed in a storage container and plastic tubes were filled from it.

  Visual inspection of plastic tubes filled in this way showed uneven bands at many fill heights.

  B) 70 kg of fully active catalyst ring and 30 kg of steatite ring from A) were introduced into a polyethylene bag. These 55 filled polyethylene bags were successively transferred to a storage container of the same catalyst filling apparatus as A), and transferred to the same plastic tube as A) by the catalyst filling apparatus at the same filling speed as A).

  Visual inspection of plastic tubes filled with this method showed no non-uniform bands.

  C) A composition of 357 g of fully active catalyst ring / 153 g of steatite ring using a fully active catalyst ring from A) (shape 5 mm × 3 mm × 2 mm) and a steatite ring of the same shape (5 mm × 3 mm × 2 mm) Part I was filled into a polyethylene bag using a packaging device (wrapping I). The total amount of Composition I charged was 5.685 metric tons.

  Furthermore, a portion of 835 g of composition II consisting only of the fully active catalyst ring from A was filled into a polyethylene bag (wrapping II). The total amount of Composition II charged was 9.308 metric tons.

  11148 contact tubes made of ferritic steel and having an inner diameter of 25.4 mm (wall thickness of 2 mm) and a length of 3.20 m are first converted into one piece using the catalyst filling device described in German Patent No. 1934324. Packet II was filled into all tubes and subsequently one packet I was transferred sequentially to all tubes. The uniform interval of filling time of the individual tubes was less than ± 5 seconds relative to the time average. The average filling time was 45 seconds. Pressure drop measurements on 200 randomly selected individual fill tubes with an air supply of 3000 Nl / l · h produced a uniformity interval for number average pressure drops of less than ± 3%.

  The filled tube is suitable for partial oxidation of propene to acrolein. Refilling to improve the uniformity recommended by WO 03/057653 was not necessary.

  US Patent No. 60/568699, filed May 7, 2004, is hereby incorporated by reference. Many modifications and variations of the present invention are possible with respect to the above concepts. Thus, it can be assumed that the invention may be practiced otherwise than as specifically described within the scope of the appended claims.

Claims (10)

Filling a large number of contact tubes with a compact so that each contact tube comprises at least two parts with different compact compositions and is evenly provided between the multiple contact tubes In that case,
(1) Packing a uniform amount of the corresponding shaped body composition into each of a number of packages and transferring the same number of packages to each separate individual part of the number of contact tubes Thereby obtaining at least two parts having a composition of the different shaped bodies filled into the multiple contact tubes,
(2) Molded body composition is a mixture of two or more types of catalyst molded bodies that differ in one or more means of shape, chemical composition of active material, physical properties of active material or mass ratio of active material
Or
Mixture of catalyst compact and dilute compact
Consists of
(3) The amount and composition in each respective package is determined by the mass or number of different catalyst compact types,
(4) The number of the packages to be transferred to different individual one parts of the multiple contact tubes is an integer from 1 to 10,
(5) the multiple contact tubes have a bundle of at least 1000 contact tubes having an internal diameter of 10-50 mm;
and
(6) Each package includes a molded body of 50 g to 5 kg.
Filling a large number of contact tubes with a compact so that each contact tube comprises at least two parts with different compact compositions and is evenly provided between the multiple contact tubes how to. The method according to claim 1, wherein the shaped body has a longest dimension of 1 to 20 mm. 3. A method according to claim 1 or 2, wherein each said contact tube comprises at least three different parts having different shaped body compositions. The method according to any one of claims 1 to 3, wherein the ratio of the inner diameter D of the contact tube to the longest dimension L of the catalyst molded body contained in the package is 2: 1 to 20: 1. The composition of the compact includes a catalyst compact having Mo-, Bi- and Fe- containing composite metal oxygen and / or a catalyst compact having Mo- and V- containing composite metal oxygen. The method of any one of 1-4. 6. A method according to any one of the preceding claims, wherein the package is packed with a sufficient amount of shaped body to supply all defined portions of the contact tube. The method according to claim 1, wherein the package is manually transferred to the contact tube. The method according to any one of claims 1 to 6, wherein the catalyst package is transferred to the contact tube by a method of a catalyst filling machine. 9. A process according to claim 8 , wherein the catalyst filling machine has a storage container corresponding to the capacity of the quantity part of the package. The number of packages to be transferred per contact tube, any one process of claim 1 which is 5 to 9.