Tubular fixed bed reactor with built-in structural member in tube pass and application of tubular fixed bed reactor

Abstract

The invention provides a tubular fixed bed reactor with a built-in structural member in a tube pass, the top and the bottom of the tube pass in the tubular fixed bed reactor are plugged with porcelain balls, the interior of the tube pass is filled with a foam metal internal member, the foam metal internal member is provided with through holes, and the through holes comprise a large hole D and a small hole d; wherein the ratio Dmax / Dmin of the maximum aperture Dmax to the minimum aperture Dmin in the macropores D is less than or equal to 3, the average aperture Da of the macropores D is 1.0 mm-5 mm, and 1.0 mm < = Dmin < = Dmax < = 10 mm, the ratio dmax / dmin of the maximum aperture dmax to the minimum aperture dmin in the macropores d is less than or equal to 10, the average aperture da of the macropores d is 0.05 mm-0. 6mm, and 0.05 mm < = dmin < = dmax < = 1.0 mm; and the ratio of the average pore diameter da of the small pores d to the average pore diameter Da of the large pores D is less than or equal to 0.155. The built-in structural member is combined with the particle size of the catalyst and the reaction pressure, so that the mass transfer and heat transfer capacities in the tube pass of the reactor are improved on the premise of not increasing the pressure drop of a catalyst bed and not sacrificing the production capacity of the reactor.

Description

Technical Field

[0001] The invention belongs to the technical field of tubular fixed bed reactors, and in particular relates to a tubular fixed bed reactor with built-in structural parts in the tubes. Background Art

[0002] At present, the highly exothermic reactors used in industry include slurry bed reactors, fluidized bed reactors, and shell-and-tube fixed bed reactors. Among them, the shell-and-tube fixed bed reactor has always attracted attention due to its simple structure, small back mixing, small catalyst wear, and easy separation of products. However, there are always problems of mass transfer and heat transfer when the shell-and-tube fixed bed reactor is used for highly exothermic reactions. In industrial production, in order to reduce the pressure drop of the catalyst bed to reduce the energy consumption of the equipment, the catalyst particles loaded in the shell-and-tube fixed bed reactor are usually >1mm. At this time, the diffusion restriction in the catalytic reaction becomes very important and will greatly affect the product selectivity. At the same time, due to the small ratio of the tube diameter to the catalyst diameter of the shell-and-tube fixed bed reactor, the wall effect in the tube will be seriously affected. In addition, the poor thermal conductivity of the catalyst will greatly limit the radial heat transfer in the tube, which is very likely to cause local overheating of the catalyst bed to appear "hot spots". In severe cases, even "flying temperature" phenomenon will occur, causing the active components of the catalyst to sinter and the catalyst performance to decline.

[0003] At present, the methods to solve or improve these problems are to prepare catalysts using metal foam as carrier or to add internal components in the tube process.

[0004] In order to improve the thermal conductivity of the catalyst and reduce the pressure drop, CN200410096609.X loads the active metal onto the foam metal, and the obtained catalyst has the advantages of high catalytic activity and good thermal conductivity. However, although the use of foam metal as a carrier catalyst can reduce the pressure drop, improve its thermal conductivity, and eliminate the influence of internal diffusion, the foam metal has a large porosity and a low specific surface area, which will lead to a low catalyst loading amount, and it is difficult to control the uniform dispersion of the active components on the foam metal carrier, making it difficult to mass produce.

[0005] CN202310311711.X fixes several internal components to the inner wall of the tube side of the tubular reactor. The internal components are plate-like structures, evenly distributed in the axial direction and extending in the axial direction. The internal components reduce the bed pressure drop and strengthen the radial heat transfer of the reactor tube side. However, the internal components fixedly connected to the wall surface will lead to a decrease in the catalyst packing density and a decrease in production capacity. Moreover, the internal components fixed in the reactor tube side are not conducive to the loading and removal of the catalyst.

[0006] CN202180074473.4 inserts a tubular insert into a tubular reactor, the tubular insert having an inner channel of varying diameter, and operates the inner channel of the tubular insert to change the profile of the internal reaction chamber, thereby improving the temperature distribution of the catalyst bed. However, in this technology, the introduced tubular insert will sacrifice part of the reactor volume, resulting in a decrease in the reactor production capacity; on the other hand, since the tubular insert is mainly placed in the upstream section of the catalyst bed, the upstream section is the part where the reaction is prone to form hot spots, but in the process of the highly exothermic reaction of Fischer-Tropsch synthesis, the catalyst will inevitably gradually deactivate, and the hot spot will move downstream of the catalyst bed, which will cause the tubular insert to be unable to continue to play its heat transfer role. Summary of the invention

[0007] In order to overcome the deficiencies in the prior art, the present invention provides a tubular fixed bed reactor with built-in structural parts in the tube side. By combining the built-in structural parts with the catalyst particle size and the reaction pressure, the mass transfer and heat transfer capacity in the reactor tube side is improved without increasing the pressure drop of the catalyst bed and without sacrificing the production capacity of the reactor.

[0008] In order to achieve the purpose of the present invention, the present invention adopts the following technical solutions:

[0009] In a first aspect, the present invention provides a tubular fixed bed reactor with a built-in structural member in a tube pass, wherein the top and bottom of the tube pass in the tubular fixed bed reactor are blocked with springs and porcelain balls, the inside of the tube pass is filled with a foam metal internal component, and the foam metal internal component is provided with a through hole, and the through hole includes a large hole D and a small hole d;

[0010] Among them, the maximum pore size D in the macropore D max With minimum aperture D min The ratio of ≤3, the average pore diameter Da of the macropore D is 1.0mm~5mm, and 1.0mm≤D min ≤D max ≤10mm; the maximum aperture d among the small holes d max With the minimum aperture d min The ratio of ≤10, the average pore diameter da of the small hole d is 0.05mm~0.6mm, and 0.05mm≤d min ≤d max ≤1.0mm; the ratio of the average pore diameter da of the small pores d to the average pore diameter Da of the large pores D is ≤0.155. In some preferred embodiments, the ratio of the total volume of the small pores d to the total volume of the large pores D in the foam metal internal component is 0.08-0.8, for example, 0.10, 0.20, 0.25, 0.50, 0.60, 0.70.

[0011] In the tubular fixed bed reactor provided by the present invention, the foam metal internal component is placed in the tube of the reactor, and a double aperture structure (i.e., including large holes D and small holes d) is provided on the foam metal internal component, or in other words, the foam metal internal component is a metal bracket composed of countless open-pore unit cells arranged in a certain manner. The foam metal internal component is generally cylindrical, and the difference between its cylindrical diameter M and the inner diameter N of the tube generally satisfies: 0.1≤NM≤1mm, which is convenient for the foam metal to be placed in the tubular reactor, and the fine annular gap between the foam metal and the inner wall of the tubular reactor can form convection-enhanced heat transfer.

[0012] The catalyst in the tubular fixed bed reactor is not loaded on the foam metal internal components, but is loaded into the large holes of the foam metal internal components in the reactor by gravity, which is convenient for production and loading and unloading, and the particle size of the catalyst particles is satisfy: In some specific embodiments, the minimum pore size D in the macropores D of the foam metal internal component is min The maximum particle size of the catalyst particles Ratio Preferably In some specific embodiments, the manufacturing method of the foam metal internal component can be sintering, electroplating, pressure casting, foaming, 3D printing, etc.

[0013] The small holes of the foam metal internal components in the shell-and-tube fixed bed reactor provided by the present invention are used to pass fluids, thereby increasing the porosity of the catalyst bed, reducing the pressure drop of the catalyst bed, improving the mass transfer capacity in the tube side of the shell-and-tube reactor, and improving product distribution; in some specific embodiments, the porosity ε of the foam metal internal components is 0.88≤ε≤0.98, for example, 0.90, 0.93, 0.95.

[0014] In the tube pass of the tubular fixed bed reactor of the present invention, the number of open-cell foam metal internal components loaded in each tubular reactor is not specifically required, but for ease of loading and disassembly, the preferred number is 1 to 10. In some specific embodiments, the volume occupied by the foam metal internal components in the tube pass of the tubular fixed bed reactor is 0.50 to 0.95, for example, 0.60, 0.65, 0.70, 0.80, 0.85.

[0015] In some specific embodiments, in order to enhance the heat transfer effect, the ratio of the inner diameter of the tube side of the shell-and-tube fixed bed reactor to the average pore diameter Da of the macropores D in the foam metal internal component is 2 to 40, for example, 4, 5, 30, 35; preferably 6 to 20, for example, 8, 10, 15, 18.

[0016] In the tubular fixed bed reactor provided by the present invention, the thermal conductivity of the foam metal internal component is greater than 10 W / m / K, preferably greater than 100 W / m / K; more specifically, the material of the foam metal internal component is preferably selected from one or more of copper, iron, aluminum, titanium, stainless steel or iron-chromium alloy. It should be noted that the material selected for the foam metal internal component will not damage the activity of the catalyst.

[0017] In the tubular fixed bed reactor provided by the present invention, the through holes on the foam metal internal components are circular, elliptical, pentagonal or hexagonal.

[0018] The tube size (internal diameter N and height H) of the tube-type fixed bed reactor of the present invention can be arbitrary. In some preferred embodiments, the inner diameter of the tube is 20 mm to 60 mm, such as 25 mm, 30 mm, 35 mm, 40 mm, 45 mm, 50 mm, 55 mm, and the height of the tube is 1 m to 15 m, such as 2 m, 4 m, 6 m, 8 m, 10 m, 12 m, 14 m. The number of tubes is not specifically limited, and is preferably 100 to 10,000.

[0019] In a second aspect, the present invention provides an application of the above-mentioned shell-and-tube fixed bed reactor, and the above-mentioned shell-and-tube reactor is used to carry out a highly exothermic reaction, for example, a Fischer-Tropsch synthesis reaction and a methanol synthesis reaction.

[0020] In some specific embodiments, the conditions for the Fischer-Tropsch synthesis reaction are: a pressure of 2 to 8 MPa, preferably 4 to 6 MPa; a temperature of 180 to 350°C, preferably 200 to 250°C.

[0021] In some specific embodiments, the catalyst active component of the Fischer-Tropsch synthesis reaction is one or more of iron, iridium, cobalt, ruthenium, rhodium, nickel, platinum, molybdenum or tungsten; the catalyst carrier is selected from aluminum oxide, titanium dioxide, silicon dioxide, activated carbon, zeolite or molecular sieve. The preparation method of the catalyst of the present invention can adopt precipitation method, impregnation method, kneading method, etc.

[0022] The above technical solution has the following technical effects:

[0023] The tubular fixed bed reactor of the present invention has a foam metal internal component with double pore sizes (large pores D and small pores d) built into the tube side, which is combined with the catalyst particle size and the reaction pressure to improve the mass transfer and heat transfer capacity in the reactor tube side without increasing the pressure drop of the catalyst bed and sacrificing the production capacity of the reactor.

[0024] The tubular fixed bed reactor provided by the present invention improves the mass transfer capacity in the tube pass, improves the product distribution, and simultaneously improves the heat transfer capacity in the tube pass, and improves the temperature distribution. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 : A schematic diagram of the filling structure of a tubular fixed bed reactor provided by the present invention;

[0026] Figure 2 : Schematic diagram of the appearance of the foam metal internal component;

[0027] Figure 3 : Schematic diagram of the microstructure of through holes in foam metal internal components;

[0028] Figure 4 : Schematic diagram of dual pore size distribution of foam metal internal components;

[0029] Figure 5 : Schematic diagram of dual pore size distribution of the foam metal internal component during the Fischer-Tropsch synthesis reaction in Comparative Example 6;

[0030] Among them, 1. tubular fixed bed reactor, 2. ceramic balls, 3. foam metal internal components, 4. catalyst, 5. large pores, 6. small pores. DETAILED DESCRIPTION

[0031] In order to facilitate the understanding of the present invention, the present invention will be further described below in conjunction with examples. It should be understood that the following examples are only for a better understanding of the present invention and do not mean that the present invention is limited to the following examples.

[0032] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

[0033] Where specific experimental steps or conditions are not specified in the examples, the corresponding conventional experimental steps or conditions in the art can be used. The instruments used without specifying the manufacturer are all conventional products that can be purchased commercially.

[0034] In the following examples, the pore size distribution and porosity were measured using the mercury intrusion method.

[0035] Example 1

[0036] The inner diameter of the tube side of the fixed bed reactor used in this embodiment is 32 mm, the height is 130 cm, and saturated water is provided outside the tube side for heat extraction. Three foam metal internal components are built into the tube side, and the material is 6061 aluminum alloy prepared by pressure casting, and the thermal conductivity is 155 W / m / K, and the porosity ε is 0.90. The through holes of the foam metal internal components are double apertures (such as Figure 3 , 4 As shown), the diameter is 31mm, the height is 105mm, the average pore size Da of the large pore D is 2mm, the average pore size da of the small pore d is 0.15mm, and the maximum pore size D in the large pore D ismax With minimum aperture D min The ratio D max / D min 2, 1.5mm≤D min ≤D max ≤3mm, the largest hole diameter d among the small holes d max With the minimum aperture d min The ratio d max / d min 5, 0.06mm≤d min ≤d max ≤0.3mm; the volume of the foam metal internals in the tube is 0.9. The ratio of the total volume of small pores to the total volume of large pores is 0.33.

[0037] The catalyst is in spherical particle form, the carrier is aluminum oxide, the active component is Co, the Co content is 25%, and the average particle size is The minimum pore size D in the large pores D of the foam metal internal component is 0.6 mm. min The maximum particle size of the catalyst particles The ratio is 2.

[0038] Will be like Figure 2 The foam metal internal components having the above characteristics are placed in the tube array, such as Figure 1 As shown, the catalyst is loaded into a tubular fixed bed reactor by gravity, and the catalyst passes through and fills the macropores of the foam metal internals (such as Figure 4 As shown), if necessary, tap the reactor lightly with a wooden hammer to ensure that the catalyst is densely packed. The final catalyst loading volume is 0.77 with a macropore volume ratio, a loading amount of 735 g, and a loading height of 105 cm.

[0039] At H2 / CO=2, space velocity 570h -1 The Fischer-Tropsch synthesis reaction was carried out at a reaction pressure of 4.0 MPa and a reaction temperature of 220°C. The experimental results are shown in Table 1.

[0040] Example 2

[0041] The inner diameter of the tube side of the tube-in-tube fixed bed reactor used in this embodiment is 32 mm, the height is 130 cm, and saturated water is provided outside the tube side for heat extraction. A foam metal internal component is built into the tube side, and the material is 6061 aluminum alloy prepared by pressure casting, and its thermal conductivity is 131 W / m / K, and its porosity ε is 0.88. The foam metal internal component has a double aperture, a diameter of 31 mm, and a height of 105 mm. The average aperture Da of the large pore D is 2.5 mm, the average aperture da of the small pore d is 0.2 mm, and the maximum aperture D in the large pore D is 0.1 mm. max With minimum aperture D min The ratio Dmax / D min 1.5,2mm≤D min ≤D max ≤3mm, the largest hole diameter d among the small holes d max With the minimum aperture d min The ratio d max / d min 6, 0.05mm≤d min ≤d max ≤0.3mm; the volume of the foam metal internals in the tube is 0.92. The ratio of the volume of small pores to the volume of large pores is 0.28.

[0042] The catalyst is in spherical particle form, the carrier is aluminum oxide, the active component is Co, the Co content is 25%, and the average particle size is The minimum pore size D in the large pores D of the foam metal internal component is 0.4 mm. min The maximum particle size of the catalyst particles The ratio is 3.5.

[0043] The above catalyst was loaded into the foam metal macropores of the tubular fixed bed reactor by gravity. If necessary, the reactor was gently tapped with a wooden hammer to ensure that the catalyst was densely packed. The final catalyst loading volume was 0.80 to the macropore volume, the loading amount was 770 g, and the loading height was 105 cm.

[0044] At H2 / CO=2, space velocity 570h -1 The Fischer-Tropsch synthesis reaction was carried out at a reaction pressure of 5.0 MPa and a reaction temperature of 220°C. The experimental results are shown in Table 1.

[0045] Example 3

[0046] The inner diameter of the tube in the tube-in-tube fixed bed reactor used in this embodiment is 32 mm, the height is 130 cm, and saturated water is used outside the tube to extract heat. Five foam metal internal components are built into the tube, made of stainless steel and prepared by 3D printing, with a thermal conductivity of 53 W / m / K and a porosity ε of 0.95. The foam metal internal components are double-aperture, with a diameter of 31 mm and a height of 105 mm. The average pore size Da of the large pore D is 4 mm, the average pore size da of the small pore d is 0.25 mm, and the maximum pore size D in the large pore D is 0.1 mm. max With minimum aperture D min The ratio D max / D min 2.5,3mm≤D min ≤D max ≤7.5mm, the largest hole diameter d among the small holes d max With the minimum aperture d min The ratio d max / dmin 9, 0.05mm≤d min ≤d max ≤0.45mm; the volume of the foam metal internals in the tube is 0.95. The ratio of the volume of small pores to the volume of large pores is 0.39.

[0047] The catalyst is in the form of spherical particles, the carrier is silicon dioxide, the active component is Co, the Co content is 30%, and the average particle size is obtained by impregnation method. The minimum pore size D in the large pores D of the foam metal internal component is 0.55 mm. min The maximum particle size of the catalyst particles The ratio is 4.

[0048] The above catalyst was loaded into the foam metal macropores of the tubular fixed bed reactor by gravity. If necessary, the reactor was gently tapped with a wooden hammer to ensure that the catalyst was densely packed. The final catalyst loading volume was 0.39 to macropore volume, the loading amount was 746 g, and the loading height was 105 cm.

[0049] At H2 / CO=2, space velocity 570h -1 The Fischer-Tropsch synthesis reaction was carried out at a reaction pressure of 3.5 MPa and a reaction temperature of 220°C. The experimental results are shown in Table 1.

[0050] Example 4

[0051] The inner diameter of the tube side of the tube-in-tube fixed bed reactor used in this embodiment is 32 mm, the height is 130 cm, and saturated water is provided outside the tube side for heat extraction. Five foam metal internal components are built into the tube side, and the material is 1070 aluminum alloy prepared by foaming method, and the thermal conductivity is 226 W / m / K, and the porosity ε is 0.92. The foam metal internal components are double aperture, with a diameter of 31 mm and a height of 105 mm. The average aperture Da of the large pores D is 5 mm, the average aperture da of the small pores d is 0.3 mm, and the maximum aperture D in the large pores D is 0.1 mm. max With minimum aperture D min The ratio D max / D min 2,4mm≤D min ≤D max ≤8mm, the largest hole diameter d among the small holes d max With the minimum aperture d min The ratio d max / d min 3, 0.2mm≤d min ≤d max ≤0.6mm; the volume of the foam metal internals in the tube is 0.85. The ratio of the volume of small pores to the volume of large pores is 0.33.

[0052] The catalyst is in the form of spherical particles, the carrier is titanium dioxide, the active component is Co, the Co content is 25%, and the average particle size is obtained by precipitation method. The minimum pore size D in the large pores D of the foam metal internal component is 0.80 mm. min The maximum particle size of the catalyst particles The ratio is 3.

[0053] The above catalyst was loaded into the foam metal macropores of the tubular fixed bed reactor by gravity. If necessary, the reactor was gently tapped with a wooden hammer to ensure that the catalyst was densely packed. The final catalyst loading volume was 0.39 to macropore volume, the loading amount was 703 g, and the loading height was 105 cm.

[0054] At H2 / CO=2, space velocity 570h -1 The Fischer-Tropsch synthesis reaction was carried out at a reaction pressure of 3.0 MPa and a reaction temperature of 220°C. The experimental results are shown in Table 1.

[0055] Comparative Example 1

[0056] This comparative example uses a tube-type fixed bed reactor with an inner diameter of 32 mm and a height of 130 cm. Saturated water is used outside the tube to extract heat. The catalyst is directly loaded in the tube. Specifically, the catalyst is a clover-shaped catalyst, the carrier is aluminum oxide, and the active component is Co, wherein the Co content is 25%, and it is prepared by impregnation. The length of the catalyst is 5 to 10 mm, the cross-sectional diameter is 1.6 mm, the catalyst loading is 850 g, the loading height is 105 cm, and the upper and lower ends of the catalyst bed are both filled with Ceramic balls are used for filling.

[0057] At H2 / CO=2, space velocity 570h -1 , reaction pressure 3.0MPa, reaction temperature 220℃, experimental results are shown in Table 1.

[0058] Comparative Example 2

[0059] The inner diameter of the tube side of the tube-type fixed bed reactor used in this comparative example is 32 mm, the height is 130 cm, and saturated water is used outside the tube side for heat extraction. Two foam metal internal components are built into the tube side, and the material is 6061 aluminum alloy prepared by pressure casting, and the thermal conductivity is 155 W / m / K and the porosity ε is 0.90. The foam metal internal component has a single pore size, and the average pore size is 2 mm, the diameter is 31 mm, and the height is 105 mm.

[0060] The catalyst is in spherical particle form, the carrier is aluminum oxide, the active component is Co, the Co content is 25%, and the average particle size is The catalyst loading amount is 980 g and the loading height is 105 cm.

[0061] At H2 / CO=2, space velocity 570h -1 The Fischer-Tropsch synthesis reaction was carried out at a reaction pressure of 4.0 MPa and a reaction temperature of 220°C. The experimental results are shown in Table 1.

[0062] Comparative Example 3

[0063] The inner diameter of the tube side of the tube-type fixed bed reactor used in this comparative example is 32 mm, the height is 130 cm, and saturated water is used outside the tube side for heat extraction. A foam metal internal component is built into the tube side, and the material is 6061 aluminum alloy prepared by pressure casting, and its thermal conductivity is 155 W / m / K, and the porosity ε is 0.90. The foam metal internal component has a single pore size, and its average pore size is 0.8 mm, the diameter is 31 mm, and the height is 105 mm.

[0064] The catalyst is in spherical particle form, the carrier is titanium dioxide, the active component is Co, the Co content is 40%, and the average particle size is The catalyst particles were coated onto the foam metal by sol method, with a coating thickness of 0.1 mm. The loading amount of the catalyst was 165 g, and the loading height was 105 cm.

[0065] At H2 / CO=2, space velocity 570h -1 The Fischer-Tropsch synthesis reaction was carried out at a reaction pressure of 3.0 MPa and a reaction temperature of 220°C. The experimental results are shown in Table 1.

[0066] Comparative Example 4

[0067] The inner diameter of the tube side of the tube fixed bed reactor used in this comparative example is 32mm, the height is 130cm, and saturated water is used to extract heat outside the tube side. Three foam metal internal components are built into the tube side, and the material is 6061 aluminum alloy prepared by pressure casting, and the thermal conductivity is 155W / m / K and the porosity ε is 0.95. The foam metal internal component has a single pore size, and its average pore size is 2mm, the diameter is 31mm, and the height is 105mm.

[0068] The catalyst is in spherical particle form, the carrier is aluminum oxide, the active component is Co, the Co content is 25%, and the average particle size is The catalyst loading amount was 1117 g and the loading height was 105 cm.

[0069] At H2 / CO=2, space velocity 570h -1 The Fischer-Tropsch synthesis reaction was carried out at a reaction pressure of 3.0 MPa and a reaction temperature of 220°C. The experimental results are shown in Table 1.

[0070] Comparative Example 5

[0071] The foam metal internal component was prepared by the same material, method and pore size distribution as in Example 1, and the catalyst was also the same, except that its porosity ε was 0.50, which not only resulted in the catalyst loading in the reactor being only 382 g, but also the reactor production capacity being only 43.5 kg / h / m under the same reaction conditions as in Example 1. 3 , and will cause the pressure drop to increase significantly to 491Pa.

[0072] Comparative Example 6

[0073] The inner diameter of the tube in the tube-in-tube fixed bed reactor is 32 mm and the height is 130 cm. There is saturated water outside the tube for heat extraction. Two foam metal internal components are built into the tube. The material is 1070 aluminum alloy prepared by pressure casting. Its thermal conductivity is 226 W / m / K and its porosity ε is 0.93. The foam metal internal component has a double aperture, a diameter of 31 mm and a height of 105 mm. The average aperture Da of the large pore D is 1.5 mm, the average aperture da of the small pore d is 0.4 mm, and the maximum aperture D in the large pore D is 0.6 mm. max With minimum aperture D min The ratio D max / D min 5, 1mm≤D min ≤D max ≤5mm, the maximum aperture d among the small holes d max With the minimum aperture d min The ratio d max / d min 3, 0.2mm≤d min ≤d max ≤0.6mm; the volume of the foam metal internals in the tube is 0.85. The ratio of the volume of small pores to the volume of large pores is 0.43.

[0074] The catalyst of Example 4 was loaded into the macropores of the foam metal of the tubular fixed bed reactor, and the final catalyst loading volume was 0.3 to the macropore volume, the loading amount was 600 g, and the loading height was 105 cm. Under the same reaction conditions as Example 4, the axial temperature difference was 18°C, the radial temperature difference was 13°C, and the catalyst space-time yield was 0.081 g CH2 / g catalyst / h. The temperature difference became larger because the ratio of the average pore diameter da (0.4 mm) of the small pore d to the average pore diameter Da (1.5 mm) of the large pore D was greater than 0.155, resulting in partial defects in the foam metal structure, and the small pores and large pores were partially fused (reference Figure 5 The defective part has a reduced heat transfer capacity, which leads to excessively high local temperature. The catalyst is prone to bridging during loading, and the loading amount is reduced. Bridging will cause channeling of gas flow, affecting the reaction effect. Reducing the loading amount will reduce the reactor capacity, resulting in C 5+ The space-time yield decreases.

[0075] Table 1 Comparison of test results

[0076]

[0077]

[0078] From the data in Table 1 above, it can be seen that compared with the case without adding the foam metal internal component (Comparative Example 1), after adding the internal component, although the catalyst loading amount is slightly reduced, the axial radial temperature difference is reduced, the catalyst bed utilization rate is improved, the CO conversion rate is improved, and the catalyst particles are reduced. + The selectivity of C5 + The space-time yield increased without any decrease in the reactor production capacity.

[0079] It can be seen from Comparative Examples 2 and 4 that when the catalyst particles are reduced, only measures such as single-pore foam metal and increased pressure can improve the axial radial temperature difference, improve the catalyst activity and reactor production capacity, but the catalyst bed pressure drop will increase significantly, which is very unfavorable to the catalyst and equipment. Comparative Example 3 coats the catalyst on foam metal, and its axial radial temperature difference is the smallest, the catalyst conversion rate is also very high, and the catalyst bed pressure drop is significantly reduced, but the reactor production capacity is greatly reduced, which will affect the economic efficiency of the enterprise.

Claims

1. A tubular fixed bed reactor with built-in structural parts in the tube path, characterized in that: The top and bottom of the tube in the tubular fixed bed reactor are blocked with porcelain balls, and the inside of the tube is filled with a foam metal internal component, and the foam metal internal component is provided with through holes, and the through holes include a large hole D and a small hole d; Among them, the maximum pore size D in the macropore D max With minimum aperture D min The ratio D max / D min ≤3, the average pore diameter Da of the macropore D is 1.0mm~5mm, and 1.0mm≤D min ≤D max ≤10mm; The maximum pore size d among the small pores d max With the minimum aperture d min The ratio d max / d min ≤10, the average pore diameter da of the small hole d is 0.05mm~0.6mm, and 0.05mm≤d min ≤d max ≤1.0mm; The ratio of the average pore diameter da of the small pores d to the average pore diameter Da of the large pores D is ≤0.

155.

2. The tubular fixed bed reactor according to claim 1, characterized in that: The porosity ε of the foam metal internal component is 0.88≤ε≤0.98; Preferably, the total volume ratio of small pores d to large pores D in the foam metal internal component is 0.08-0.

8.

3. The tubular fixed bed reactor according to claim 1 or 2, characterized in that: The foam metal internal component occupies 0.5 to 0.95 of the volume of the tube pass, and the number of the foam metal internal components in the tube pass of the tubular fixed bed reactor is 1 to 10.

4. The tubular fixed bed reactor according to any one of claims 1 to 3, characterized in that: The particle size of the catalyst particles loaded in the tubular fixed bed reactor is satisfy: Preferably, the minimum pore size D in the macropore D is min The maximum particle size of the catalyst particles Ratio Preferably 5. The tube-in-tube fixed bed reactor according to claim 4, characterized in that: The ratio of the inner diameter of the tube side of the tubular fixed bed reactor to the average pore diameter Da of the macropores D in the foam metal internal component is 2 to 40, preferably 6 to 20; Preferably, the inner diameter of the tube is 20 mm to 60 mm, and the height is 1 m to 15 m.

6. The tube-in-tube fixed bed reactor according to claim 5, characterized in that: The thermal conductivity of the foam metal internal component is greater than 10 W / m / K, preferably greater than 100 W / m / K; The material of the foam metal inner component is preferably selected from one or more of copper, iron, aluminum, titanium, stainless steel or iron-chromium alloy.

7. The tube-in-tube fixed bed reactor according to claim 6, characterized in that: The through holes on the foam metal inner component are in the shape of a circle, an ellipse, a pentagon or a hexagon.

8. Use of the tubular fixed bed reactor according to any one of claims 1 to 7, characterized in that: Applicable to strong exothermic reactions; The highly exothermic reaction is, for example, a Fischer-Tropsch synthesis reaction and a methanol synthesis reaction.

9. The use according to claim 8, characterized in that: The conditions of the Fischer-Tropsch synthesis reaction are: pressure of 2-8 MPa, preferably 4-6 MPa; temperature of 180-350°C, preferably 200-250°C.

10. The use according to claim 9, characterized in that: The catalyst active component of the Fischer-Tropsch synthesis reaction is one or more of iron, iridium, cobalt, ruthenium, rhodium, nickel, platinum, molybdenum or tungsten; The carrier of the catalyst is selected from alumina, titanium dioxide, silicon dioxide, activated carbon, zeolite or molecular sieve.

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