Multiple pipe type reaction container

Abstract

To provide a multiple pipe type reaction container which is excellent in cooling efficiency, and can easily and efficiently replace a catalyst to be filled.SOLUTION: A multiple pipe type reaction container 1 includes an inside cooling pipe 3 with catalysts which makes a cooling fluid flow therein and has catalysts 9 provided on its outer peripheral surface, a reaction gas flowing pipe 5 to which the inside cooling pipe 3 with the catalysts is inserted so as to take out and pull the inside cooling pipe 3 with the catalysts, and that makes reaction gas flow therein, and an outside cooling container 7 which is provided on the outer periphery of the reaction gas flowing pipe 5, makes the cooling fluid flow therein and cools the outer peripheral surface of the reaction gas flowing pipe 5, wherein the catalysts 9 are provided so as to be divided into a plurality of catalysts 9 in the flow direction of the cooling fluid, and can be independently replaced.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a reaction vessel having a catalyst-equipped reaction gas flow tube through which a reaction gas flows and in which a catalyst is provided, and in particular to a multi-tube reaction vessel in which the reaction vessel has multiple tubes. [Background technology]

[0002] Catalytic reactions are often exothermic, and as the reactor scale increases, there is a concern that abnormal heat generation within the catalyst bed may cause the reaction to go out of control or damage the catalyst and equipment, so a cooling mechanism is important. For example, Patent Document 1 discloses a method in which a heat transfer tube through which a refrigerant flows is provided in a catalyst packed bed to cool the packed bed.

[0003] In addition, the activity of the catalyst gradually decreases due to poisoning by impurities contained in the raw materials, adhesion of products to the catalyst surface, etc. For this reason, the catalyst packed in the reactor is generally replaced periodically.

[0004] As a method for replacing a catalyst, for example, Patent Document 2 discloses a technique in which the tip of a double pipe is cut open, a vacuum pump hose is inserted to suck out the filler, and the pipe is refilled and then welded shut. Moreover, Patent Document 3 discloses a method in which a fluid is fed into a tube filled with a catalyst to flush out the filler. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2003-229147 A [Patent Document 2] Japanese Patent Application Publication No. 10-328555 [Patent Document 3] Japanese Patent Publication No. 60-71036 Summary of the Invention [Problem to be solved by the invention]

[0006] Regarding the cooling mechanism, the method of Patent Document 1 has a problem in that the cooling efficiency is good in the areas close to the heat transfer tubes in the packed bed, but is poor in areas away from the heat transfer tubes, such as near the wall of the packed container.

[0007] In addition, in the method of Patent Document 2, the replacement of the catalyst requires the use of a vacuum pump to suck out the catalyst. In addition, since the catalyst is sucked up, the catalyst may fall due to the effect of gravity, making it difficult to recover all of it. Furthermore, in Patent Document 2, the container must be cut open prior to recovery of the catalyst, and the cut portion must be welded shut after filling, which is problematic in terms of labor and cost.

[0008] Furthermore, the method of Patent Document 3 has a problem in that it requires power to transport the fluid. In addition, when the filler is pushed away, depending on the shape of the container, the filler may be structurally trapped, making it impossible to recover the entire amount.

[0009] The activity of a catalyst generally decreases from the upstream side in the flow of the reaction gas, so even if the overall catalyst yield decreases, the catalyst on the downstream side may not be significantly deteriorated. However, in all of the above cited documents, the entire amount of catalyst is replaced when the catalyst is replaced. Therefore, even catalysts that are not very deteriorated (i.e., catalysts that have not reached the end of their replacement life) are subject to replacement, which poses a problem in that the catalyst is not utilized efficiently.

[0010] The present invention has been made to solve the above problems, and has an object to provide a multi-tube reaction vessel which has excellent cooling efficiency and in which the catalyst packed therein can be easily and efficiently replaced. [Means for solving the problem]

[0011] (1) A multi-tube reaction vessel according to the present invention comprises: an inner cooling pipe with a catalyst, through which a cooling fluid flows and on which a catalyst is provided on an outer peripheral surface; a reaction gas flow pipe into which the inner cooling pipe with a catalyst is removably inserted and through which a reaction gas flows; and an outer cooling vessel, which is provided on the outer periphery of the reaction gas flow pipe and through which a cooling fluid flows to cool the outer peripheral surface of the reaction gas flow pipe; The catalyst is divided into a plurality of parts in the flow direction of the cooling fluid and is characterized in that it is individually replaceable.

[0012] (2) In addition, in the above-mentioned (1), the inner cooling pipe with catalyst is characterized in that a porous catalyst layer is fixed to the outer periphery of a metal cooling pipe body, and the cooling pipe body is connected so as to be separable in the axial direction.

[0013] (3) In addition, in the above-mentioned (2), the porous catalyst layer is fixed to the outer periphery of the cooling pipe body via an intermediate layer, and the intermediate layer has a function of reducing the difference in thermal expansion coefficient between the porous catalyst layer and the cooling pipe body.

[0014] (4) In the above (2) or (3), a baffle plate is provided which is disposed adjacent to the inner surface of the reaction gas flow pipe to prevent the porous catalyst layer from contacting the inner surface of the reaction gas flow pipe and which provides resistance to the flow of the reaction gas.

[0015] (5) In addition, in the above-mentioned (1), the inner cooling pipe with catalyst is characterized in that a plurality of cage members containing a catalyst are provided on the outer periphery of the cooling pipe body.

[0016] (6) In the above-mentioned (5), the cage member is capable of being individually removed from the cooling pipe body.

[0017] (7) Furthermore, in the device described in (5) above, the cage member is fixed to the cooling pipe main body, and the cooling pipe main body is connected to the cage member in an axially separable manner.

[0018] (8) In the device described in (5) above, the cage member has an opening and closing door for inserting and removing the catalyst.

[0019] (9) Furthermore, in any one of the above (1), (2), (3), (5), (6), (7), or (8), the present invention is characterized in that it comprises a catalyst layer temperature detection unit which detects the temperature of at least one of the catalysts divided into a plurality of parts; a catalyst temperature comparison unit which inputs detection information detected by the catalyst layer temperature detection unit and compares the current catalyst temperature based on the detection information with the undegraded catalyst temperature when the catalyst is not degraded; a catalyst replacement determination unit which determines whether or not each catalyst needs to be replaced based on the comparison result of the catalyst temperature comparison unit; and a notification unit which notifies the fact when the catalyst replacement determination unit determines that replacement is necessary.

[0020] (10) In the device according to (9) above, the catalyst layer temperature detection unit detects the temperature of each of the catalyst layers divided into a plurality of catalyst layers, a reactant gas supply property detector that detects a temperature, a pressure, a flow rate, and a concentration of the reactant gas supplied to the reactant gas flow pipe; an exhaust reaction gas property detection unit that detects the temperature, pressure, flow rate, and concentration of the reaction gas exhausted from the reaction gas flow pipe; a wall surface temperature detection unit that detects a wall surface temperature of the reaction gas flow pipe; A database of physical properties of the reaction gas flow pipe material and catalyst; a catalyst layer temperature distribution estimation unit that estimates an undegraded catalyst temperature in an undegraded state of each of the catalysts based on the temperature detection unit, the supply reaction gas property detection unit, the exhaust reaction gas property detection unit, the wall surface temperature detection unit, and the physical property database, The catalyst temperature comparison unit is characterized in that it compares the undegraded catalyst temperature estimated by the catalyst layer temperature estimation unit with the temperature detected by the catalyst layer temperature detection unit. Effect of the Invention

[0021] According to the present invention, when it is time to replace the catalyst, only the catalyst whose performance has decreased due to the progress of deterioration can be replaced, thereby reducing catalyst costs. [Brief description of the drawings]

[0022] [Figure 1] FIG. 1 is an explanatory diagram of a multi-tube reaction vessel according to a first embodiment. [Diagram 2] FIG. 2 is a view showing a state in which an inner cooling tube with a catalyst of the multi-tubular reaction vessel according to the first embodiment is pulled out from a reaction gas flow tube. [Diagram 3] FIG. 2 is a partial cross-sectional view of the multi-tube reaction vessel shown in FIG. [Figure 4] FIG. 2 is an explanatory diagram of one embodiment of an inner cooling tube with a catalyst in the multi-tube reaction vessel shown in FIG. [Diagram 5] 2 is an explanatory diagram of another embodiment of the inner cooling tube with catalyst in the multi-tube reaction vessel shown in FIG. 1. FIG. [Figure 6] 6 is an explanatory diagram of a method for replacing a catalyst in the catalyst-equipped inner cooling tube shown in FIG. 5. FIG. [Figure 7] 2 is an explanatory diagram of another embodiment of the inner cooling tube with catalyst in the multi-tube reaction vessel shown in FIG. 1. FIG. [Figure 8] FIG. 2 is an explanatory diagram of an embodiment in which baffle plates are provided in the multi-tube reaction vessel shown in FIG. [Figure 9] 5 is an explanatory diagram of the function when the baffle plate of FIG. 4 is provided. FIG. [Figure 10] FIG. 11 is an explanatory diagram of another embodiment of the baffle plate (part 1). [Figure 11] FIG. 2 is an explanatory diagram of another embodiment of the baffle plate (part 2). [Figure 12] FIG. 4 is an explanatory diagram of another embodiment of the baffle plate (part 3). [Figure 13]FIG. 4 is an explanatory view of another aspect of the multi-tube reaction vessel according to the first embodiment. [Figure 14] FIG. 11 is an explanatory diagram of an inner cooling tube with a catalyst of a multi-tube reaction vessel according to a second embodiment. [Figure 15] 15 is an explanatory view of another embodiment of a cage member provided in the catalyst-equipped inner cooling pipe shown in FIG. 14. [Figure 16] FIG. 11 is an explanatory diagram of one aspect of an inner cooling pipe with a catalyst in the second embodiment. [Figure 17] FIG. 11 is an explanatory view of another aspect of the inner cooling pipe with catalyst in the second embodiment. [Figure 18] 13 is an explanatory diagram of a catalyst replacement method in another aspect of the catalyst-equipped inner cooling pipe of the second embodiment. FIG. [Figure 19] 13 is an explanatory diagram of a catalyst replacement method in another aspect of the cage member of the catalyst-equipped inner cooling tube of embodiment 2. FIG. [Figure 20] 13 is an explanatory diagram of a catalyst replacement method in another aspect of the cage member of the catalyst-equipped inner cooling tube of embodiment 2. FIG. [Figure 21] FIG. 11 is an explanatory view of another aspect of the inner cooling pipe with catalyst in the second embodiment. [Figure 22] FIG. 11 is an explanatory view of another aspect of the inner cooling pipe with catalyst in the second embodiment. [Diagram 23] FIG. 11 is an explanatory diagram of an inner cooling tube with a catalyst of a multi-tube reaction vessel according to embodiment 3. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0023] [Embodiment 1] A multi-tube reaction vessel 1 according to this embodiment includes an inner cooling tube 3 with a catalyst, a reaction gas flow tube 5, and an outer cooling vessel 7, as shown in FIGS. Each component will be described in detail below.

[0024] <Inner cooling tube with catalyst> The catalyst-equipped inner cooling pipe 3 has a catalyst 9 provided on the outer peripheral surface of a metal cooling pipe body 3a through which a cooling fluid flows, and the catalyst 9 is cooled from the inside by the cooling fluid flowing through the cooling pipe body 3a. The catalyst 9 is divided into a plurality of parts in the flow direction of the cooling fluid, and can be individually replaced.

[0025] 3, the catalyst-equipped inner cooling pipe 3 is removably inserted into the reaction gas flow pipe 5, and in the inserted state, the space between the inner surface of the reaction gas flow pipe 5 and the outer surface of the catalyst 9, i.e., the space in which the catalyst 9 is arranged, becomes the space through which the reaction gas flows. When the reaction gas passes through the catalyst 9 arranged in this space, a catalytic reaction takes place.

[0026] A cover member 11 is attached to the upper part of the catalyst-equipped inner cooling pipe 3, closing the upper end opening 5a (see Figure 2) of the reaction gas flow pipe 5 with the catalyst-equipped inner cooling pipe 3 inserted into the reaction gas flow pipe 5. In addition, the lower end of the catalyst-equipped inner cooling pipe 3 is adapted to close the lower end opening 5b (see FIG. 2) of the reaction gas flow pipe 5 when the catalyst-equipped inner cooling pipe 3 is inserted into the reaction gas flow pipe 5.

[0027] An example of the catalyst 9 of the catalyst-equipped inner cooling pipe 3 is a porous catalyst layer 9a formed and fixed (integrated) on the outer circumferential surface of the cooling pipe body 3a constituting the catalyst-equipped inner cooling pipe 3, as shown in Fig. 3. If the porous catalyst layer 9a is a ceramic or carbon-based material such as alumina, silica, or zeolite, the film is formed directly by CVD or sputtering, or a precursor gel or slurry is formed by dip coating or wash coating. After film formation, it is heated to adhere and fix. In addition, in the case of a zeolite material, it is possible to directly synthesize and form a membrane by hydrothermal synthesis.

[0028] Since the cooling pipe body 3a is made of metal, it is preferable to provide an intermediate layer 13 made of a cermet or a binder material, as shown in the enlarged view of FIG. 3, in order to reduce the difference in thermal expansion coefficient between the metal and the porous catalyst layer 9a (oxide carrier) and to ensure adhesion.

[0029] In this example, the cooling fluid flows from the top to the bottom of the inner cooling pipe 3 with catalyst. Examples of cooling fluids include, but are not limited to, air, inert gas, water, seawater, ethylene glycol, and the like.

[0030] In the case where the catalyst 9 is a porous catalyst layer 9a, a method for making the catalyst 9 provided in a plurality of divided parts, that is, the porous catalyst layers 9a, individually replaceable will be described. As shown in Fig. 4, the cooling pipe body 3a has a structure in which a plurality of short pipes are connected in series in the axial direction. In the example shown in Fig. 4, the upper end pipe 3a to which the uppermost cover member 11 is attached is t and upper end tube 3a t Three intermediate tubes 3a, each having a porous catalyst layer 9a fixed thereto, are provided below the intermediate tubes 3a. i and the lowest intermediate tube 3a i A connecting pipe 3a is connected to the external pipe. c It is composed of the following: In addition, the connecting pipe 3a c 3a i Alternatively, the lowermost one of the two may be provided integrally therewith.

[0031] As shown in FIG. 5, the upper end tube 3a t Only the upper end tube 3a is expanded. t The lower surface of the upper end tube 3a may be abutted against the upper end surface of the reaction gas flow tube 5. t can have the function of the lid member 11.

[0032] The activity of the catalyst 9 generally decreases from the upstream side in the flow of the reaction gas, so that the catalyst 9 on the downstream side does not deteriorate so much even if the overall catalyst yield decreases. In this respect, in the present embodiment, when replacing the intermediate pipe 3a, the most upstream (lowest end) intermediate pipe 3a, which is deteriorated, is replaced as shown in FIG. i Remove the deteriorated intermediate tube 3a and replace it with a new intermediate tube 3a. i For example, the upper end tube 3a tThe replaced intermediate tube 3a should be installed directly below the i The new intermediate tube 3a is at the top, the one that was at the top before the replacement is now the second one from the top, and the one that was second from the top before the replacement is now the third one from the top, i.e., the bottom one. i The installation position is the upper end pipe 3a t However, the present invention is not limited to this and the intermediate pipe may be installed at any position in combination with other intermediate pipes before replacement. In this way, only the catalyst 9 whose performance has decreased due to the progress of deterioration is replaced, and thus the catalyst cost can be reduced.

[0033] <Reaction gas flow tube> The catalyst-equipped inner cooling pipe 3 is removably inserted into the reaction gas flow pipe 5, and the reaction gas flows inside. A gas inlet 15 through which the reaction gas enters is provided at the bottom of the reaction gas flow pipe 5, and a gas outlet 17 through which the reaction gas (which may contain liquid) is discharged is provided at the top of the reaction gas flow pipe 5. Therefore, the flow of the reaction gas in the reaction gas flow pipe 5 is from bottom to top, opposite to the flow of the cooling fluid in the inner cooling pipe 3 with catalyst, and is a counterflow to the cooling fluid. Note that, as in this example, the reaction gas and the cooling fluid may be counterflowed, and in some cases, the reaction gas and the cooling fluid may be parallel flowed to preferentially cool the superheated part (gas inlet part).

[0034] <Outer cooling container> The outer cooling vessel 7 is provided on the outer periphery of the reaction gas flow pipe 5 and cools the outer periphery of the reaction gas flow pipe 5 by passing a cooling fluid therethrough. 1, the outer cooling vessel 7 of this embodiment is made of a cylinder having a larger diameter than the reaction gas flow pipe 5, and is provided with a cooling fluid inlet 19 on the upper side and a cooling fluid outlet 21 on the lower side. Therefore, the flow of the cooling fluid in the outer cooling vessel 7 is from top to bottom, similar to the catalyst-containing inner cooling pipe 3, and is a counterflow to the reaction gas.

[0035] In the multi-tube reaction vessel 1 configured as above, with the catalyst-carrying inner cooling tube 3 inserted into the reaction gas flow tube 5, a cooling fluid flows through the catalyst-carrying inner cooling tube 3 and the outer cooling vessel 7. When the reaction gas flows through the reaction gas flow pipe 5, reaction heat is generated by a catalytic reaction when the reaction gas passes through the porous catalyst layer 9a. This reaction heat is cooled from the inside by the cooling fluid flowing through the catalyst-equipped inner cooling pipe 3 and from the outside by the cooling fluid flowing through the outer cooling vessel 7.

[0036] As described above, in this embodiment, the heat of catalytic reaction is cooled from both the inside and outside, so that the cooling efficiency is good. In addition, by being able to cool from both the inside and outside, it is possible to reduce temperature unevenness in the catalyst 9 and suppress the occurrence of hot spots (a phenomenon in which a very small part of the packed bed generates abnormal heat).

[0037] In this embodiment, the inner cooling pipe 3 with catalyst is disposed approximately at the center of the reaction gas flow pipe 5, so that cooling from the inside can be performed evenly. Similarly, the reaction gas flow pipe 5 is disposed approximately at the center of the outer cooling vessel 7, so that cooling from the outside can be performed evenly. However, since the present invention is characterized by cooling the catalyst 9 from the inside and the outside, it is not limited to the case where the inner cooling pipe 3 with catalyst is disposed at the center of the reaction gas flow pipe 5, nor is it limited to the case where the reaction gas flow pipe 5 is disposed at the center of the outer cooling vessel 7.

[0038] Furthermore, according to this embodiment, when it is time to replace the catalyst 9, as described above, the catalyst-equipped inner cooling pipe 3 is pulled out from the reaction gas flow pipe 5, and only the catalyst 9 whose performance has decreased due to the progress of deterioration is replaced, thereby making it possible to reduce catalyst costs. In addition, since the catalyst 9 is not discharged by gravity during replacement, the inner cooling tube 3 with catalyst can be placed horizontally or upside down, and the installation position of the multi-tube reaction vessel 1 is not limited.

[0039] In the above example, the catalyst-equipped inner cooling pipe 3 is inserted from one side of the reaction gas flow pipe 5. However, as shown in FIG. 7, the catalyst-equipped inner cooling pipe 3 may be made divisible and connectable in the middle so that it can be inserted from both sides of the reaction gas flow pipe 5. In this case, when replacing the filter, for example, the one on the upstream side may be removed as a deteriorated product and replaced with a new one, or the one attached on the downstream side may be moved to the upstream side and the new product may be provided on the downstream side.

[0040] As shown in FIG. 8, it is preferable to provide a baffle plate 23 on the outer periphery of the inner cooling pipe, which is disposed close to the inner surface of the reaction gas flow pipe 5 (dotted line in FIG. 8) to prevent the porous catalyst layer 9a (two-dot chain line in FIG. 8) from contacting the inner surface of the reaction gas flow pipe 5 and to provide resistance to the flow of the reaction gas. Note that the porous catalyst layer 9a is not shown in FIG. 8. The baffle plate 23 shown in FIG. 8 is annular and has many gas passage holes 23a through which the reaction gas passes. By providing the gas passage holes 23a, the reaction gas is guided to the porous catalyst layer 9a side by the baffle plate 23, as shown in FIG. 9, and contact with the porous catalyst layer 9a is improved. The baffle plate 23 is also expected to have a holding effect on the porous catalyst layer 9a.

[0041] The outer diameter of the baffle plate 23 is approximately equal to the inner diameter of the reaction gas flow pipe 5, and the outer diameter of the porous catalyst layer 9a is slightly smaller than the outer diameter of the baffle plate 23. The reason for this is as follows. By providing such a baffle plate 23, a small gap can be maintained between the porous catalyst layer 9a and the inner surface of the reaction gas flow pipe 5, and the porous catalyst layer 9a can be prevented from adhering to the inner surface of the reaction gas flow pipe 5 due to the catalytic reaction.

[0042] When it is time to replace the catalyst 9, the catalyst-attached inner cooling pipe 3 is pulled out from the reaction gas flow pipe 5, and the replacement target, for example, the intermediate pipe 3a i(see FIG. 4) is removed and a new inner cooling pipe 3 with catalyst attached is inserted. At this time, if the porous catalyst layer 9a hits the inner surface of the reaction gas flow pipe 5 during removal or insertion, it will be damaged. However, since the outer peripheral end face of the baffle plate 23 protrudes beyond the porous catalyst layer 9a, it is possible to prevent the porous catalyst layer 9a from hitting the inner surface of the reaction gas flow pipe 5. The baffle plate 23 is disposed between the intermediate pipe 3a and the inner cooling pipe 3 with the catalyst. i It is preferable to provide a

[0043] As another embodiment of the baffle plate 23, as shown in FIG. 10, semicircular rings divided in half in the circumferential direction may be provided at positions shifted in the axial direction.

[0044] Furthermore, if the outer peripheral end face of the baffle plate 23 abuts against the inner peripheral face of the reaction gas flow pipe 5, it is difficult to smoothly insert or remove the baffle plate 23, so it is preferable to provide a small gap. However, if there is a gap, the reaction gas will pass through the gap, so as shown in Fig. 11, a protrusion 25 that protrudes slightly around the entire circumference may be provided on the inner surface of the reaction gas flow pipe 5, and the outer peripheral end of the baffle plate 23 may be placed on the protrusion 25. In this way, the gap is blocked by the protrusion 25 and the baffle plate 23, so that the reaction gas is guided to the porous catalyst layer 9a side, and the catalytic reaction can be carried out more reliably.

[0045] When a plurality of baffle plates 23 are provided, it is necessary to prevent interference between the baffle plates 23 and the protrusions 25 when inserting and removing the catalyst-equipped inner cooling pipe 3 into and from the reaction gas flow pipe 5. For this reason, for example, as shown in Fig. 12, the inner surface of the reaction gas flow pipe 5 may be tapered so that the diameter of the baffle plates 23 decreases downward, and the diameter of the baffle plates 23 on the lower side may be made smaller, so that the lower baffle plates 23 do not interfere with the upper protrusions 25.

[0046] In the above embodiment, the thickness of the porous catalyst layer 9a fixed to the cooling pipe main body 3a is constant, but by forming the cooling pipe main body 3a into a tapered surface that narrows in diameter downward, as shown in Fig. 13, the thickness of the porous catalyst layer 9a can be made thinner at the top and thicker toward the bottom. In this way, if the reaction gas is introduced from the top where the layer thickness is thin, the amount of catalyst in contact with the reaction gas at the top is small, so heat generation in the catalyst layer due to the catalytic reaction can be suppressed, and at the bottom, although the layer thickness of the catalyst layer is thicker, the amount of unreacted reaction gas is small, so heat generation is suppressed, and as a result, the temperature gradient from upstream to downstream can be equalized. Furthermore, by making the cooling pipe main body 3a have a tapered surface and the upper part slightly larger than the inner diameter of the reaction gas flow pipe 5, the upper end opening 5a of the reaction gas flow pipe 5 can be closed simply by inserting the inner cooling pipe 3 with catalyst into the reaction gas flow pipe 5, and the cover member 11 can be omitted.

[0047] [Embodiment 2] In the first embodiment, the catalyst-equipped inner cooling pipe 3 has a cooling pipe main body 3a that can be divided into a plurality of parts, and a porous catalyst layer 9a is formed on and fixed (integrated) to the outer circumferential surface of the cooling pipe main body 3a. In this embodiment, as an aspect of the catalyst-equipped inner cooling pipe 3, as shown in Figure 14, multiple cage members 27 containing a catalyst 9 are attached to the cooling pipe main body 3a, and the catalyst 9 can be replaced for each cage member 27. As in the first embodiment, the present embodiment also has a reaction gas flow pipe 5 and an outer cooling vessel 7, but as these are the same as in the first embodiment, a description thereof will be omitted.

[0048] In the example shown in FIG. 14, the cooling pipe main body 3a is made of a single pipe body that is not divided, and a cage member 27 is fixed to such a cooling pipe main body 3a. 14, the cage member 27 has a flat cylindrical shape and is fixed to the cooling pipe main body 3a with the cooling pipe main body 3a inserted through the center. The mesh of the cage member 27 is smaller than the particle size of the catalyst 9 to be filled, and is sized so that the catalyst 9 does not escape from the cage member 27. It should be noted that the basket member 27 is not limited to a mesh-like member, but may be a cylindrical plate member with small holes therein.

[0049] Each cage member 27 is fixed to the cooling pipe main body 3a, and is provided with an opening / closing door 29 as shown in Fig. 14, and the catalyst 9 can be discharged or filled into each cage member 27 by opening the opening / closing door 29. The opening / closing door 29 may be provided on the side of the cage member 27 as shown in Fig. 14, or the top surface may be made openable and closable as the opening / closing door 29 as shown in Fig. 15.

[0050] 16 and 17 show a state in which the catalyst-equipped inner cooling pipe 3 of this embodiment is inserted into the reaction gas flow pipe 5. Fig. 16 corresponds to Fig. 4 of the first embodiment, and Fig. 17 corresponds to Fig. 5 of the first embodiment.

[0051] In addition, the cage members 27 may be made individually removable from the cooling pipe main body 3a, in which case, as shown in Fig. 18(a), an insertion hole 31 through which the cooling pipe main body 3a can be inserted is provided in the center of the cage member 27, and as shown in Fig. 18(b), the cooling pipe main body 3a is inserted into the insertion hole 31, and when in use, the cage member 27 is fixed to the cooling pipe main body 3a, and when replacing the catalyst, the cage members 27 are released and removed from the cooling pipe main body 3a. In this way, the cage members 27 can be replaced together without providing each cage member 27 with an opening / closing door 29 for inserting and removing the catalyst 9, making the replacement work easier.

[0052] As a method for removing the cage members 27 from the cooling pipe main body 3a, the cage members 27 of each stage may be formed by splitting a cylindrical body in half, as shown in Fig. 19(a). In this way, as shown in Fig. 19, with a plurality of cage members 27 attached to the cooling pipe main body 3a, only the cage member 27 to be replaced can be removed from the cooling pipe main body 3a and replaced. In the example shown in FIG. 19, one cage member 27 is made up of two members, but one cage member 27 may be made up of three or more members.

[0053] 20(a), a recessed portion 33 recessed from the side wall to the center may be provided in a part of a cylindrical cage member 27, and as shown in Fig. 20(b), a cooling pipe main body 3a may be placed in the recessed portion 33 and the cage member 27 may be fixed to the cooling pipe main body 3a with a gas-impermeable fixing member 35. In this way, just the cage member 27 to be replaced can be removed from the cooling pipe main body 3a and replaced, similarly to the case of Fig. 19.

[0054] 21 and 22, the cage member 27 may be fixed to the cooling pipe main body 3a so that the cooling pipe main body 3a can be separated in the axial direction. Fig. 21 corresponds to Fig. 4 of the first embodiment, and Fig. 22 corresponds to Fig. 5 of the first embodiment.

[0055] [Embodiment 3] The multi-tube reactor 37 according to this embodiment is a multi-tube reactor 37 that can inform the timing of replacement when replacing a catalyst 9 that has deteriorated (reaching the end of its replacement life), and as shown in FIG. 23, includes a catalyst layer temperature detection unit 39, a supply reaction gas property detection unit 41, an exhaust reaction gas property detection unit 43, a wall surface temperature detection unit 45, a reaction gas flow pipe material / catalyst physical property database 47, a catalyst layer temperature distribution estimation unit 49, a catalyst temperature comparison unit 51, a catalyst replacement judgment unit 53, and an alarm unit 55. Each component will be described in detail below. In FIG. 23, the same parts as those in FIG. 1 are denoted by the same reference numerals and the description thereof will be omitted.

[0056] <Catalyst layer temperature detection unit> The catalyst layer temperature detection unit 39 detects the temperature of each of the catalysts 9 provided from the upstream side to the downstream side.

[0057] <Supply reaction gas property detection unit> The supplied reactant gas property detection unit 41 detects the temperature, pressure, flow rate, and concentration of the reactant gas supplied to the reactant gas flow pipe 5 .

[0058] <Exhaust reaction gas property detection unit> The discharged reaction gas property detection unit 43 detects the temperature, pressure, flow rate, and concentration of the reaction gas discharged from the reaction gas flow pipe 5 .

[0059] <Wall surface temperature detection unit> The wall surface temperature detector 45 detects the wall surface temperature of the reaction gas flow pipe 5 .

[0060] <Reaction gas flow pipe material and catalyst property database> The reaction gas flow pipe material / catalyst physical property database 47 stores the material of the reaction gas flow pipe 5 and the physical property values ​​of the catalyst 9 . Specifically, C bed :Catalytic heat capacity, q react : Molar reaction heat, M bed : amount of catalyst, k: reaction rate constant, a1: reaction order, a2: reaction order, h: heat transfer coefficient, U: catalyst heat transfer coefficient, cp: gas specific heat, ρ: gas density, α: conversion coefficient from molar flow rate to volumetric flow rate (e.g., 22.4 for mol / s to L / s (standard conditions)).

[0061] <Catalyst layer temperature distribution estimation section> The catalyst layer temperature distribution estimation unit 49 estimates the undegraded catalyst temperature at each of multiple locations on the undegraded catalyst 9 based on the exhaust reaction gas property detection unit 43, the wall surface temperature detection unit 45, and the physical properties database. The undegraded catalyst temperature is the catalyst temperature at the time when heat is generated by catalytic reaction when reaction gas passes through the catalyst 9 when it is not degraded. When the reaction gas composition does not fluctuate, the temperature that the catalyst exhibits at the beginning of the reaction (initial temperature) may be used as the undegraded catalyst temperature.

[0062] The undegraded catalyst temperature can be estimated by solving the following heat balance equation at each position where the catalyst layer temperature detector 39 is installed. [Temperature of catalyst layer after time Δt] = [Temperature of catalyst layer at reference time] + [Heat received by catalyst layer during time Δt] / [Heat capacity of catalyst layer] [Heat received by the catalyst layer] = [Reaction heat generated by the catalytic reaction] + [Heat flowing in from the boundary of the region] + [Heat brought in by the inflowing gas] - [Heat removed by the outflowing gas] The desired [temperature of the catalyst layer after time Δt] is Tpred Then, the specific calculation formula is as follows:

[0063] T pred =T0+Q all / C bed Here, T pred : predicted temperature (= packed bed temperature after Δt time), Δt: calculation time T0: Catalyst layer temperature at the reference time Q all : Heat gain of catalyst C bed : Catalyst heat capacity Q all =Q r +Q w +Q in -Q out -Q gas Here, Q r : Total reaction heat Q w : Heat from the wall Q in : Heat from upstream Q out : Heat to downstream Q gas : Heat gain from gas Q r =q react ×r×M bed ×Δt r=k×P1 a1 ×P2 a2 (For two-component reactions) P1 = P0 x C1, P2 = P0 x C2 Here, q react : Molar reaction heat r: Molar reaction rate M bed :Catalyst amount k: reaction rate constant P1: Component 1 partial pressure a1: reaction order P2: Component 2 partial pressure a2: Reaction order P0: Total pressure C1: Component 1 concentration C2: Component 2 concentration Q w =h×(T0-T w ) Where, h: heat transfer coefficient T w :Wall temperature Q in =U×(T up -T0) Here, T up : Upstream catalyst temperature at the reference time (if the target layer is the upstream end, set separately*) *Approximately the wall temperature, for example. The same applies to the downstream end. U: Catalyst heat transfer coefficient Q out =U×(T0-T down ) Here, T down : Downstream catalyst temperature at the reference time (if the target layer is the downstream end, set separately) Q gas =cp×ρ×F×Δt×(T0-T up ) Where, cp: gas specific heat ρ: Gas density F: Gas volume flow rate F = F0 + r × M bed ×Δt×α Where, F0: inlet gas volume flow rate α: Conversion coefficient from molar flow rate to volumetric flow rate (e.g., 22.4 for mol / s to L / s (standard conditions))

[0064] In the above calculation, the database of physical properties of reaction gas flow pipe materials and catalysts 47 is referred to. bed :Filled bed heat capacity, q react : Molar reaction heat, M bed : catalyst loading, k: reaction rate constant, a1: reaction order, a2: reaction order, h: heat transfer coefficient, U: catalyst heat transfer coefficient, cp: gas specific heat, ρ: gas density, α: molar flow rate. In addition, T0: catalyst layer temperature at the reference time is obtained from the catalyst layer temperature detector, P0: total pressure is obtained from the gradient of Pgi of the supply reaction gas property detector and Pgo of the exhaust reaction gas property detector, C1: component 1 concentration and C2: component 2 concentration are obtained from the gradient of Cgi of the supply reaction gas property detector and Cgo of the exhaust reaction gas property detector, T w :The wall temperature is measured from the wall temperature detector, T up The upstream catalyst temperature at the reference time is the catalyst layer temperature detection part Tc1 From T down The downstream catalyst temperature at the reference time is the catalyst layer temperature detection part T c4 and F0: inlet gas volumetric flow rate is obtained from the supply reactant gas property detector.

[0065] <Catalyst temperature comparison section> The catalyst temperature comparison unit 51 compares the catalyst temperature estimated by the catalyst layer temperature distribution estimation unit 49 with the temperature detected by the catalyst layer temperature detection unit 39 .

[0066] <Catalyst replacement judgment unit> The catalyst replacement determination unit 53 determines whether or not the catalyst 9 needs to be replaced based on the comparison result of the catalyst temperature comparison unit 51 . As the deterioration of the catalyst 9 progresses, the amount of heat generated by the catalytic reaction decreases, and the difference with the temperature of the undegraded catalyst increases. Therefore, the catalyst replacement determination unit 53 determines that replacement is necessary when the difference between the current temperature of the catalyst layer and the undegraded catalyst temperature exceeds a preset value.

[0067] <Notification Department> The notification unit 55 notifies the user when it is determined by the catalyst replacement determination unit 53 that replacement is required. Specific examples of the notification may include visual notification, such as displaying "replacement required" on a monitor or turning on a lamp, or audio notification, such as sounding an alarm.

[0068] According to this embodiment, even when the properties of the reaction gas vary, deterioration of the catalyst 9 can be appropriately determined.

[0069] In addition, when the properties of the reaction gas do not fluctuate, the supply reaction gas property detection unit 41, the exhaust reaction gas property detection unit 43, the wall temperature detection unit 45 and the reaction gas flow piping material / catalyst physical property database 47 are not required, and the catalyst temperature comparison unit 51 inputs the detection information detected by the catalyst layer temperature detection unit 39 and compares the current catalyst temperature based on the detection information with the undegraded catalyst temperature when the catalyst 9 is not degraded.

[0070] In this case, the catalyst layer temperature detection unit 39 may be provided corresponding to each of the multiple catalysts 9, or may be provided only for the catalyst 9 to be replaced, for example, only for the most upstream catalyst 9, and when that catalyst 9 needs replacement, replacement as shown in Figure 5 is performed. [Explanation of symbols]

[0071] 1. Multi-tube reaction vessel 3 Inner cooling tube with catalyst 3a Cooling pipe body 3a t upper end tube 3a i Intermediate Tube 3a c Connecting Pipe 5. Reaction gas flow tube 5a Top opening 5b Bottom opening 7 Outer cooling vessel 9. Catalyst 9a Porous catalyst layer 11 Cover member 13. Middle Class 15 Gas inlet 17 Gas exhaust port 19 Cooling fluid inlet 21 Cooling fluid outlet 23 Baffle plate 23a Gas passage hole 25 Protrusion 27 Cage parts 29 Opening and closing doors 31 Insertion hole 33 Depression 35 Fixing member 37 Multi-tube reaction vessel (embodiment 3) 39 Catalyst layer temperature detection unit 41 Supply reaction gas property detection unit 43 Exhaust reaction gas property detection unit 45 Wall temperature detector 47 Database of properties of reaction gas flow pipe materials and catalysts 49 Catalyst layer temperature distribution estimation section 51 Catalyst temperature comparison section 53 Catalyst replacement judgment unit 55 Notification Department

Claims

1. a catalyst-equipped inner cooling pipe through which a cooling fluid flows and which has a catalyst provided on its outer peripheral surface; a reaction gas flow pipe into which the catalyst-equipped inner cooling pipe is removably inserted and through which a reaction gas flows; and an outer cooling vessel which is provided on the outer periphery of the reaction gas flow pipe and through which a cooling fluid flows to cool the outer peripheral surface of the reaction gas flow pipe, The catalyst is divided into a plurality of parts in the flow direction of the cooling fluid, and each part can be individually replaced.

2. 2. The multi-tube reaction vessel according to claim 1, wherein the inner cooling pipe with catalyst is formed by fixing a porous catalyst layer to the outer periphery of a metal cooling pipe body, and the cooling pipe body is connected in an axial direction so as to be separable.

3. 3. The multi-tube reaction vessel according to claim 2, wherein the porous catalyst layer is fixed to an outer periphery of the cooling pipe body via an intermediate layer, and the intermediate layer has a function of reducing a difference in thermal expansion coefficient between the porous catalyst layer and the cooling pipe body.

4. 4. The multi-tube reaction vessel according to claim 2 or 3, further comprising a baffle plate disposed adjacent to an inner surface of the reaction gas flow pipe to prevent the porous catalyst layer from contacting the inner surface of the reaction gas flow pipe and to provide resistance to a flow of the reaction gas.

5. 2. The multi-tube reaction vessel according to claim 1, wherein the inner cooling tube with catalyst is configured such that a plurality of basket members containing a catalyst are provided on the outer periphery of a cooling tube body.

6. 6. The multi-tube reaction vessel according to claim 5, wherein the cage member is individually removable from the cooling tube body.

7. 6. The multi-tube reaction vessel according to claim 5, wherein the cage member is fixed to the cooling pipe body, and the cooling pipe body is connected to the cage member in an axially separable manner.

8. 6. The multi-tube reaction vessel according to claim 5, wherein the cage member has an opening / closing door for inserting and removing the catalyst.

9. 9. The multi-tube reaction vessel according to claim 1, further comprising: a catalyst layer temperature detection unit which detects a temperature of at least one of the catalysts divided into a plurality of parts; a catalyst temperature comparison unit which receives detection information detected by the catalyst layer temperature detection unit and compares a current catalyst temperature based on the detection information with an undegraded catalyst temperature when the catalyst is not degraded; a catalyst replacement determination unit which determines whether or not each catalyst needs to be replaced based on a comparison result of the catalyst temperature comparison unit; and a notification unit which notifies the fact when the catalyst replacement determination unit determines that the catalyst needs to be replaced.

10. The catalyst layer temperature detection unit detects the temperature of each of the catalyst layers divided into a plurality of catalyst layers, a reactant gas supply property detector that detects the temperature, pressure, flow rate, and concentration of the reactant gas supplied to the reactant gas flow pipe; an exhaust reaction gas property detection unit that detects the temperature, pressure, flow rate, and concentration of the reaction gas exhausted from the reaction gas flow pipe; a wall surface temperature detection unit that detects a wall surface temperature of the reaction gas flow pipe; A database of physical properties of the reaction gas flow pipe material and catalyst; a catalyst layer temperature distribution estimation unit that estimates an undegraded catalyst temperature in an undegraded state of each of the catalysts based on the temperature detection unit, the supply reaction gas property detection unit, the exhaust reaction gas property detection unit, the wall surface temperature detection unit, and the physical property database, 10. The multi-tube reactor according to claim 9, wherein the catalyst temperature comparison unit compares the undegraded catalyst temperature estimated by the catalyst layer temperature estimation unit with the temperature detected by the catalyst layer temperature detection unit.

Images