JP2013081898A - Granular substance-filling device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a granular substance-filling device hardly causing formation of a bridge by the granular substance, and capable of uniformly supplying the granular substance to a plurality of reaction tubes.SOLUTION: This granular substance-filling device includes a plurality of hoppers arranged in parallel to one another, and transport paths each arranged on the output side of each hopper, wherein the hopper includes a rear side wall located on the upstream side of the transport path, the rear side wall is tilted so that its lower side is located on the downstream side of the transport path relative to its upper side, and a projection vector L to the transport path of a normal vector H toward the inside of the hopper has a part becoming nonparallel to the downstream direction of the transport path. Alternatively, the granular substance filling device includes a plurality of hoppers arranged in parallel to one another, transport paths each arranged on the output side of each hopper, and input parts each arranged on the output side of each transport path, wherein the input part is formed by connecting a lower cylinder having a small caliber to the lower side of an upper cylinder having a large caliber by shifting the axis thereof.

Description

  The present invention relates to an apparatus for filling a fixed-bed multitubular reactor with particulates such as a catalyst.

  2. Description of the Related Art Conventionally, a granular material filling apparatus for supplying granular materials such as a catalyst to a fixed bed multitubular reactor and filling each reaction tube of the reactor with the granular material is known. For example, Patent Document 1 includes a plurality of hoppers and a trough-shaped transport path provided on the exit side of each hopper, and the granular material is transported by vibrating the trough-shaped transport path with a vibrator. And a granular material filling device that is supplied to each reaction tube of the reactor from an opening formed at the tip of the conveyance path. Patent Document 2 is a granular material filling device having a plurality of hoppers, a conveyance path provided on the exit side of each hopper, and an inclined surface chute provided on the exit side of each conveyance path, A conveyor is provided on the bottom surface of the conveyance path, and a granular material filling apparatus is disclosed in which the granular material is conveyed through the conveyance path by the conveyor and supplied to each reaction tube of the reactor through a chute.

JP 2000-37621 A JP 2006-142297 A

  In the granular material filling apparatus, it is required as performance that the granular material can be uniformly supplied to a plurality of reaction tubes. That is, it is necessary that the granular material be smoothly transported from the hopper to the reaction tube. However, in the granular material filling apparatus, a bridge made of the granular material may be formed in the course of conveying the granular material, and in that case, it becomes difficult to uniformly supply the granular material to the plurality of reaction tubes.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a granular material filling apparatus that can hardly form a bridge due to granular materials and can uniformly supply the granular materials to a plurality of reaction tubes. There is.

  The granular material filling device of the present invention that has solved the above problems is a granular material filling device that supplies granular materials to each reaction tube of a fixed-bed multitubular reactor, and is a plurality of the granular material filling devices arranged in parallel. Each hopper and a transport path provided on the exit side of each hopper, the hopper has a rear side wall located on the upstream side of the transport path, and the lower side of the rear side wall is a transport path from above. In addition, the projection vector L onto the conveyance path of the normal vector H that is directed to the inside of the hopper has a portion that is not parallel to the downstream direction of the conveyance path. It has the characteristics. If the rear side wall of the hopper is formed in this way, the granular material is less likely to have the vertical drag of the vector H received from the inner side surface of the rear side wall directed to the front side wall located on the downstream side of the conveying path. It becomes difficult to form a bridge between the front wall and the front wall. As a result, the granular material is smoothly supplied from the hopper to the conveyance path, and the granular material is easily supplied uniformly to the reaction tube.

  In the hopper, it is preferable that the front side wall located on the downstream side of the transport path is formed substantially vertically. If the front side wall is formed in this way, it becomes difficult for the granular material to form a bridge between the rear side wall and the front side wall.

  The rear side wall is preferably formed in a V-shaped or U-shaped horizontal cross section. If the rear side wall is formed in this way, a portion where the projection vector L of the normal vector H toward the inside of the hopper on the rear side wall is not parallel to the downstream direction of the conveyance path is a portion of the rear side wall. It occupies most of the rear side wall in the horizontal section, and it becomes difficult for the particulate matter to form a bridge between the rear side wall and the front side wall.

  The present invention is also a granular material filling device for supplying granular material to each reaction tube of a fixed bed multitubular reactor, provided with a plurality of hoppers arranged in parallel and on the outlet side of each hopper. It has a conveyance path and an input part provided on the exit side of each conveyance path, and the input part is connected to the lower cylinder having a small diameter on the lower side of the upper cylinder having a large diameter while shifting the axis. A granular material filling device is provided. If the charging part is formed in this way, a difference occurs in the falling speed of the granular material in the charging part, and it becomes difficult for the granular material to form a bridge in the charging part. As a result, the particulate matter is easily supplied uniformly to the reaction tube.

  Even in the granular material filling apparatus in which the lower portion of the upper cylinder having the large diameter is connected to the lower cylinder having the small diameter and the shaft is shifted from each other, the rear side wall of the hopper is located above the lower portion. In addition to being inclined so as to be located on the downstream side of the conveyance path, the projection vector L of the normal vector H toward the inside of the hopper onto the conveyance path has a portion that is not parallel to the downstream direction of the conveyance path. It is preferable.

  It is preferable that the input portion is positioned such that the axis of the upper cylinder is located more distally than the axis of the lower cylinder when viewed from the conveyance path. If the input part is formed in this way, it becomes more difficult for the granular material to form a bridge in the input part.

  It is preferable that a hole through which the powdery material is removed is formed on the bottom surface of the conveyance path. By providing a hole through which the powdered material is removed on the bottom surface of the conveyance path, only the granular material is easily supplied to the reaction tube. As a result, it becomes easy to make the pressure loss of the reaction tube uniform.

  In the granular material filling apparatus of the present invention, it is difficult for the granular material to form a bridge in the hopper or the charging portion, and it becomes easy to uniformly supply the granular material to a plurality of reaction tubes.

An example of the side view of the granular material filling apparatus of this invention is represented. The top view of the granular material filling apparatus shown in FIG. 1 is represented. The perspective view of a part of hopper and conveyance path of the granular material filling apparatus shown in FIG. 1 is represented. The enlarged view of the hopper shown in FIG. 3 is represented. Another example of a hopper is shown. 6A shows an enlarged view of a part of the granular material filling apparatus shown in FIG. 2 and a part of the conveyance path, and FIG. 6B shows an input part of the granular material filling apparatus shown in FIG. An enlarged view of a part of the conveyance path is shown. FIG. 7A shows another example of a top view of a part of the input unit and the conveyance path, and FIG. 7B shows a side view thereof. FIG. 8A shows another example of a top view of a part of the input unit and the conveyance path, and FIG. 8B shows a side view thereof. Represents a reference example of a hopper. FIG. 10A shows a reference example of a top view of a part of the input unit and the conveyance path, and FIG. 10B shows a side view thereof.

  The granular material filling apparatus of the present invention supplies granular material to each reaction tube of a fixed bed multitubular reactor. By using the granular material filling device of the present invention, it becomes easy to supply an equal amount of granular materials such as catalyst to a plurality of reaction tubes of a fixed bed multitubular reactor, and the granular materials are uniformly distributed to the plurality of reaction tubes. Easy to fill.

  The granular material filling apparatus of the present invention can be used to fill a granular material for a generally used fixed-bed multitubular reactor. In the fixed bed multitubular reactor, a plurality of reaction tubes are preferably arranged in a substantially vertical direction. The reaction performed in the fixed bed multitubular reactor is not particularly limited, and the reaction raw material introduced into the reaction tube is not particularly limited.

  As the reaction tube of the fixed bed multitubular reactor, a general tube having a circular cross section may be used. The inner diameter of the reaction tube is not particularly limited, but is preferably 15 mm or more, more preferably 20 mm or more, further preferably 22 mm or more, more preferably 50 mm or less, more preferably 40 mm or less, and still more preferably 38 mm or less. The length of the reaction tube is determined according to the capability of the related equipment, but may be appropriately selected within a range of 1 m to 10 m.

  Examples of the particulate material include a catalyst and an inert substance. Preferably, a catalyst is used as at least one of the particulates.

  Examples of the catalyst include granular catalysts used for gas phase catalytic oxidation reaction, ammoxidation reaction, hydrogenation reaction, dehydrogenation reaction and the like. As the catalyst, the catalytically active component may be used as it is, or a molded catalyst obtained by mixing the catalytically active component with a powdery substance that is inactive to the reaction may be used. You may use the supported catalyst which carry | supported.

  Examples of the inert substance include a support for supporting the catalyst in filling the fixed bed multi-tubular reactor; a catalyst diluent; a substance used as a reaction gas preheating layer or a cooling layer, and the like. Specific examples include, for example, refractories formed from silica, alumina, silica alumina, metal (stainless steel, iron, etc.), silicon carbide, titania, magnesia, steatite, earthenware, porcelain, various ceramics, etc. Is mentioned. The inert substance means a substance that is generally inactive with respect to a reaction raw material, a target product, and the like.

  The shape of the granular material is not particularly limited, and examples thereof include a columnar shape, a ring shape, a spherical shape, and an indefinite shape.

  The size of the granular material is not particularly limited as long as it fits in the reaction tube, but the particle size (d) of the granular material has a ratio D / d of 2/1 or more in relation to the inner diameter (D) of the reaction tube to be filled. It is preferably 2.5 / 1 or more, more preferably 15/1 or less, and even more preferably 10/1 or less. The particle size (d) of the granular material is the diameter when the shape of the granular material is spherical, the diameter of a circular cross section or multiple circular cross section when it is a cylinder or ring shape, and the case of other shapes. Means the longest distance between any two points of the granular material. Furthermore, when the shape of the granular material is a cylinder or a ring, the ratio h / φ of the height (h: length in the direction perpendicular to the cross-section) to the cross-sectional diameter (φ) is 0.3 / 1 or more and 3 / 1 or less is preferable.

  The structure of the granular material filling device of the present invention will be described with reference to the drawings. The present invention is not limited to the embodiment shown in the drawings. 1 shows a side view of the granular material filling device, FIG. 2 shows a top view of the granular material filling device shown in FIG. 1, and FIG. 3 shows one of the hopper and conveyance path of the granular material filling device shown in FIG. The perspective view of a part is represented.

  The granular material filling apparatus 1 includes a plurality of hoppers 11 arranged in parallel and a conveyance path 2 provided on the exit side of each hopper 11. The particulate matter is stored in the hopper 11, supplied from the outlet of the hopper 11 to the transport path 2, and then supplied to each reaction tube through the transport path 2.

  A plurality of hoppers 11 and transport paths 2 are provided, and one transport path 2 corresponds to one hopper 11. In the figure, eight hoppers and eight conveyance paths are provided, but the number of hoppers and conveyance paths is not particularly limited as long as it is two or more. In the granular material filling device 1, a certain amount of granular material is supplied from each hopper 11 to the conveyance path 2, and a certain amount of granular material is supplied to each supply pipe through the conveyance path 2.

  The hopper 11 stores the particulate matter and supplies the particulate matter to each conveyance path 2. The hopper 11 has an upper opening and a lower opening, and supplies the granular material to the hopper from the upper opening, and the granular material in the hopper is supplied to the conveying path 2 by dropping from the lower opening. One of the transport paths 2 is provided below each lower opening.

  A plurality of hoppers 11 are arranged in parallel. Specifically, a plurality of hoppers 11 are arranged in parallel corresponding to the plurality of transport paths 2. The plurality of hoppers may be arranged independently. For example, the plurality of hoppers may be arranged apart from each other. However, as shown in FIG. 3, the plurality of hoppers 11 are preferably arranged adjacent to each other. At this time, as shown in FIG. 3, it is preferable that the left and right side walls 14 substantially parallel to the conveying direction (downstream direction) F of the granular material in the conveying path 2 are provided in each hopper 11 substantially vertically (substantially vertically). The adjacent hoppers 11 are preferably divided by the side walls 14.

  The plurality of hoppers 11 preferably have substantially the same shape. If a plurality of hoppers are formed in this way, a certain amount of particulate matter is easily supplied from each hopper.

  The conveyance path 2 is a path for transferring the granular material supplied from the hopper 11 to each reaction tube. The granular material is conveyed from the upstream side to the downstream side of the conveying path 2. For example, in FIGS. 1 and 2, the granular material is conveyed from the left side to the right side of the drawing. In the present invention, “upstream” and “downstream” do not represent elevation, but represent the direction of conveyance. That is, the “upstream side” represents the start point side of the conveyance, and the “downstream side” represents the end point side of the conveyance. The “downstream direction” means a direction in which the granular material is transported through the transport path, and means a direction in which the width center line of the transport path extends.

  The conveyance path 2 is provided so as to connect the outlet (lower opening) of the hopper 11 and the reaction tube. That is, each transport path 2 is provided below the outlet (lower opening) of any hopper 11 and above any reaction tube. The conveyance path 2 is preferably formed in a bowl shape as shown in FIG. 3, and as a result, the granular material is suitably conveyed along the conveyance path 2. Moreover, it is preferable that each conveyance path 2 has the width | variety beyond the internal diameter of a reaction tube.

  The conveyance path 2 is preferably provided with conveyance means such as a conveyor. In FIG. 1, the bottom surface of the conveyance path 2 is a conveyor 3, and the belt 4 surface of the conveyor 3 is provided substantially horizontally. In FIG. 1, the conveyor 3 is provided on the upstream side of the conveyance path 2, and thereafter, the conveyance path 2 is provided with the downstream side inclined downward. That is, in FIG. 1, the granular material is supplied from the hopper 11 and is conveyed to the downstream side by the conveyor 3 up to the middle of the conveying path 2, and thereafter is further conveyed to the downstream side by natural flow. In addition, a conveyance means is not limited to a conveyor, For example, a granular material may be conveyed downstream by vibrating a conveyance path with a vibrator. Further, the conveyance path may be provided substantially horizontally, or the downstream side may be provided inclined upward or downward.

  A plurality of transport paths 2 are arranged in parallel. As shown in the figure, it is preferable that each conveyance path extends linearly, and it is preferable that the respective conveyance paths are arranged in parallel to each other. In addition, each conveyance path may be distribute | arranged mutually non-parallel, for example, a conveyance path may be distribute | arranged radially.

  By the way, in a granular material filling apparatus, it is calculated | required as performance that a granular material can be uniformly supplied to a some reaction tube. That is, it is necessary that the granular material be smoothly transported from the hopper to the reaction tube. However, in the granular material filling device, a bridge due to the granular material is likely to be formed in the hopper or in the connection portion supplied from the conveyance path to the reaction tube, and as a result, the granular material may be clogged in the hopper or in the connection portion. is there.

  Therefore, in the granular material filling apparatus of the present invention, the shape of the hopper and the shape of the connection portion between the conveyance path and the reaction tube are devised to suppress the formation of bridges due to the granular material, and to prevent the clogging of the granular material. Yes.

  The shape of the hopper will be described. The hopper 11 has a rear side wall 12 located on the upstream side of the conveyance path 2, and the rear side wall 12 is inclined so that the lower side thereof is located on the downstream side of the conveyance path 2 from above. If the rear side wall 12 of the hopper 11 is provided so as to be inclined so that the lower side is located on the downstream side of the transport path 2 from above, the rear side wall 12 when the particulate matter is transported to the downstream side of the transport path 2. The granular material is easily supplied to the conveyance path 2 along the path. At this time, the rear side wall 12 is preferably formed to have an inclination angle larger than the repose angle of the granular material.

  However, when the rear side wall 12 of the hopper 11 is inclined as described above, the granular material is pushed into the lower portion of the hopper 11 on the rear side wall 12, and as a result, the granular material is formed in the hopper 11. It becomes easy to form a bridge. At this time, if the rear side wall 12 is provided so that the projection vector of the normal vector of the inner side surface of the rear side wall 12 onto the conveyance path 2 is parallel to the downstream direction of the conveyance path 2, the particulate matter is bridged. It becomes easy to form. This can be explained as follows.

  In FIG. 9, in the hopper of the granular material filling apparatus shown in FIG. 3, the rear side wall is planar, that is, the projection vector of the normal vector on the inner side surface of the rear side wall to the transport path is parallel to the downstream direction of the transport path. A hopper provided with a rear side wall is shown. FIG. 9 shows one hopper placed on a plane P parallel to the transport path. On the rear side wall 12 of the hopper 11, the projection vector L of the normal vector H toward the inside of the hopper 11 onto the plane P is parallel to the downstream direction F of the transport path. At this time, the granular material receives the vertical drag of the vector H from the inner side surface of the rear side wall 12, but the rear side wall 12 is such that the projection vector L of the vector H onto the plane P is parallel to the downstream direction F of the transport path. If provided, the granular material easily forms a bridge in the hopper 11 along the downstream direction F of the conveyance path. That is, the granular material easily forms a bridge between the rear side wall 12 and the front side wall 13 of the hopper 11. In addition, the front side wall 13 means the side wall of the hopper located in the downstream of a conveyance path.

  Therefore, in the granular material filling device according to the present invention, the rear side wall of the hopper is provided so as to be inclined so that the lower side is located on the downstream side of the conveying path from the upper side, and the normal vector H toward the inside of the hopper is provided. The projection vector L onto the transport path is formed so as to have a portion that is not parallel to the downstream direction of the transport path. This will be described with reference to FIG.

  FIG. 4 shows the hopper 11 extracted from the granular material filling apparatus 1 shown in FIG. FIG. 4 shows one hopper 11 placed on a plane P parallel to the transport path 2. In FIG. 4, the inner side surface of the rear side wall 12 of the hopper 11 is formed in a horizontal cross-section V shape. The rear side wall 12 is composed of two planes so that the horizontal cross section forms a V-shape, and the projection vector L of the normal vector H toward the inside of the hopper 11 in each plane onto the conveyance path is in the downstream direction of the conveyance path. Non-parallel to F. When the rear side wall 12 is formed in this way, the vertical force of the vector H received from the inner side surface of the rear side wall 12 becomes difficult for the granular material to go to the front side wall 13, and the granular material becomes difficult to move between the rear side wall 12 and the front side wall 13. It becomes difficult to form a bridge between them. As a result, the granular material is smoothly supplied from the hopper 11 to the transport path 2, and the granular material is easily supplied uniformly to the reaction tube. The V-shape is not limited to a V-shape whose cross section is symmetric, and includes a V-shape whose cross-section is asymmetrical. That is, the V shape may be any shape having a cross section formed by a combination of two straight lines.

  In FIG. 5, the other example of the hopper with which the granular material filling apparatus of this invention is equipped was shown. FIG. 5A shows a hopper 11 formed on the inner surface of the rear side wall 12 in a V shape with the bottom cut off in a horizontal section. In the hopper of FIG. 5A, the rear side wall 12 is parallel to a portion 12a in which the projection vector L of the normal vector H toward the inside of the hopper onto the conveyance path is non-parallel to the downstream direction of the conveyance path. Part 12b. Thus, the rear side wall 12 of the hopper 11 does not have to occupy all the portions where the projection vector L is non-parallel to the downstream direction of the transport path, and only a part of the rear side wall 12 is projected vector. It suffices if L is formed so as to be non-parallel to the downstream direction of the transport path.

  FIG. 5B shows a hopper formed in a U-shape in a horizontal cross section on the inner side surface of the rear side wall 12. Also in the hopper of FIG. 5B, the rear side wall 12 has a portion where the projection vector L of the normal vector H toward the inside of the hopper 11 onto the conveyance path is non-parallel to the downstream direction of the conveyance path. Yes. The U shape may be any shape in which the bottom is formed in a curved shape in the cross-sectional shape. For example, a part of the cross-sectional shape may be configured by a straight line in addition to the curve, and the cross-sectional shape is symmetrical. Or left-right asymmetrical.

  On the rear side wall 12 of the hopper, a portion 12a (hereinafter, referred to as “non-parallel portion”) in which the projection vector L of the normal vector H toward the inside of the hopper onto the conveyance path is non-parallel to the downstream direction of the conveyance path. Is preferably formed at least at the lower end of the rear side wall. Specifically, the non-parallel portion 12a is preferably formed in a portion of 1/3 or more starting from the lower end 12L of the rear side wall 12 and extending from the lower end 12L of the rear side wall 12 to the upper end 12U. , More preferably ½ or more, and more preferably from the lower end 12L of the rear side wall 12 to the upper end 12U. Thus, if the non-parallel part 12a is formed, a granular material will become easy to discharge | emit suitably from the lower side opening of a hopper, without forming a bridge | bridging in a hopper.

  The non-parallel portion 12 a is preferably formed on the rear side wall 12 so as to occupy 1/2 or more of the inner side surface in the horizontal cross section of the rear side wall 12. More preferably, the non-parallel portion 12a occupies 2/3 or more of the inner surface in the horizontal cross section of the rear side wall 12, and more preferably occupies 3/4 or more. For example, if the rear side wall is formed in a V-shaped horizontal section as shown in FIG. 4 or the rear side wall is formed in a U-shaped horizontal section as shown in FIG. A mode in which most (or substantially the whole) of the inner side surface is occupied in the horizontal cross section of the side wall, and the non-parallel portion is thus formed is particularly preferable. Moreover, it is preferable that the non-parallel part which occupies the said predetermined ratio of an inner surface in the horizontal cross section of a rear side wall is formed in the lower side edge part of a rear side wall at least as demonstrated above.

  The non-parallel portion is preferably a portion where the projection vector L of the normal vector H directed toward the inside of the hopper does not intersect with the projection onto the conveyance path of the front side wall. The normal vector H is assumed to have an infinite length with the inner surface of the rear side wall 12 as a starting point. If the non-parallel portion is defined in this way, it becomes difficult for the granular material to form a bridge between the rear side wall and the front side wall.

  On the other hand, the shape of the front side wall 13 of the hopper is not particularly limited. For example, the front side wall 13 may be provided so as to be inclined such that the lower side thereof is located on the upstream side of the transport path 2 from the upper side, and may further have a non-parallel portion like the rear side wall 12. However, as shown in FIGS. 1 to 5, the front side wall 13 is preferably formed substantially vertically. Note that “substantially vertical” is based on a horizontal plane and means substantially vertical. If the front side wall 13 is thus formed, it becomes difficult for the granular material to form a bridge between the rear side wall 12 and the front side wall 13.

  It is preferable that a gate is provided on the front side wall so that the height of the lower end can be adjusted. By adjusting the height of the lower end of the front side wall, the amount of the granular material supplied from the hopper to the conveyance path can be adjusted.

  Next, the shape of the connection portion between the conveyance path and the reaction tube will be described. As shown in FIG. 1, a loading portion 21 is provided on the exit side of each conveyance path 2. The input part 21 is provided in order to introduce the granular material conveyed by the conveyance path 2 into each reaction tube. As shown in FIG. 1, the charging unit 21 is preferably provided with an upper end connected to the lower side of the conveyance path 2, and the lower end of the charging unit 21 is directly connected to a reaction tube or a hose. It is preferable to be connected to the reaction tube through the like.

  By the way, when the charging unit 21 has a simple cylindrical shape or a shape in which a cylinder is connected to the tip of a cone or a quadrangular pyramid, the granular material forms a bridge in the charging unit 21, and the granular material is It becomes easy to clog. Therefore, in the granular material filling device 1 of the present invention, the shape of the charging unit 21 is devised so that the granular material is not easily clogged by the charging unit 21. This will be described with reference to FIG.

  6A shows an enlarged view of a part of the charging unit 21 and the conveyance path 2 of the granular material filling apparatus 1 of FIG. 2, and FIG. 6B shows the granular material filling apparatus 1 of FIG. An enlarged view of a part of the input unit 21 and the conveyance path 2 is shown. That is, FIG. 6A shows a top view of a part of the input unit and the conveyance path, and FIG. 6B shows a side view thereof.

  The insertion portion 21 is formed by connecting a lower cylinder 24 having a small diameter to the lower side of the upper cylinder 22 having a large diameter while shifting the axis. If the charging part 21 is formed in this manner, it is considered that a difference occurs in the falling speed of the granular material in the charging part 21 and it becomes difficult for the granular material to form a bridge in the charging part 21. That is, a part of the granular material that has entered the feeding portion 21 from the supply path 2 falls directly from the upper cylinder 22 to the lower cylinder 24, and the falling speed increases, while the other portion from the upper cylinder 22 to the lower cylinder. When falling to 24, the drop speed falls upon hitting the connecting portion 26 between them, and it is considered that the formation of a bridge in the 21 parts of the granular material is suppressed by this difference in drop speed. As a result, the particulate matter is continuously supplied to the reaction tube, and the particulate matter is easily filled uniformly in the reaction tube.

  In FIG. 6, the shaft 23 of the upper cylinder 22 is positioned more distally than the shaft 25 of the lower cylinder 24 as viewed from the conveyance path 2. If the input part 21 is formed in this way, it becomes more difficult for the granular material to form a bridge in the input part 21. The reason is not clear, but it can be considered as follows. That is, when the granular material is conveyed from the supply path 2 to the input portion 21, the amount of the granular material is easily introduced into the input portion 21 toward the distal side as viewed from the conveying path 2 due to the momentum of conveyance. At this time, if the shaft 23 of the upper cylinder 22 is located further on the distal side than the shaft 25 of the lower cylinder 24, the granular material introduced more in the distal side hits the connecting portion 26 and falls. It is considered that the flow is dispersed and it becomes difficult for the granular material to form a bridge in the input portion 21.

  If the lower cylinder 24 is connected to the upper cylinder 22 by shifting the axis, the insertion portion 21 is formed so that the shaft 23 of the upper cylinder 22 is seen from the conveyance path 2 from the shaft 25 of the lower cylinder 24. It is not necessarily located on the distal side. For example, as shown in FIG. 7 (FIG. 7A shows another example of a top view of a part of the feeding portion and the conveyance path, and FIG. 7B shows a side view thereof) The shaft 23 may be located closer to the proximal side of the lower cylinder 24 than the shaft 25, as shown in FIG. 8 (FIG. 8 (a) shows the top surface of the input portion and part of the transport path. FIG. 8B shows a side view thereof), and the shaft 23 of the upper cylinder 22 may be located on the left side or the right side as viewed from the conveyance path 2 with respect to the shaft 25 of the lower cylinder 24. . 7 and FIG. 8, the bridge formation suppression effect by the granular material can be obtained.

  As a reference example, FIG. 10 shows an insertion portion formed by connecting an upper cylinder 22 having a large diameter and a lower cylinder 24 having a small diameter so that the axes thereof coincide with each other (FIG. 10A). 10 (b) shows a side view thereof), and in this case, most of the granular material introduced from the supply path 2 into the input section 21 It becomes easy to hit the connecting portion 26 between the upper cylinder 22 and the lower cylinder 24. Therefore, the granular materials are likely to fall at the same speed in the charging portion 21, and the granular materials are likely to form a bridge in the charging portion 21. In particular, the granular material easily forms a bridge on the basis of the connection portion 26.

  A more preferable aspect of the charging unit 21 will be described. As shown in FIGS. 6-8, it is preferable that the connection part 26 between the upper side cylinder 22 and the lower side cylinder 24 is gradually reducing the cross-sectional diameter below. If the charging part 21 is formed in this way, when the granular material falls in the charging part 21, it becomes difficult for the granular material to stay in the connecting part 26, and the granular material is difficult to form a bridge in the charging part 21. . At this time, in the cross section including both the shafts 23 and 25 of the upper cylinder 22 and the lower cylinder 24, the connecting portion 26 has a maximum angle with respect to the respective shafts 23 and 25 in a range of 2 ° to 40 ° (more preferably 5 ° to It is preferably formed so as to be within a range of 30 °.

  The inner diameter of the upper cylinder 22 is preferably 1.1 times or more, more preferably 1.2 times or more, more preferably 2.5 times or less, and more preferably 2.0 times or less that of the lower cylinder 24. When the inner diameter of the upper cylinder 22 is 1.1 times or more than the inner diameter of the lower cylinder 24, when the granular material falls in the input portion 21, the granular material easily hits the connecting portion 26, and the granular material becomes the input portion 21. It becomes difficult to form a bridge inside. If the inner diameter of the upper cylinder 22 is 2.5 times or less than the inner diameter of the lower cylinder 24, when the granular material falls in the input portion 21, the granular material is less likely to stay at the connecting portion 26, and the granular material is It becomes difficult to form a bridge within 21.

The upper cylinder 22 and the lower cylinder 24 are preferably positioned as follows. That is, the axial distance X of the upper cylinder and lower cylinder is preferably at least 0.5 times the difference between R _U -R _D of radius R _D of radius R _U and the lower cylinder of the upper cylinder, 0. more preferably 7 times or more, more preferably 0.9 times or more, and particularly preferably equal to R _U -R _D substantially. In the case the center distance X of the upper cylinder and lower cylinder is equal to R _U -R _D, compared to a plane perpendicular to the upper cylinder and the lower cylinder axis, the projected projection circle of the lower cylinder of the upper cylinder It will be inscribed in the circle.

  As described above, in the granular material filling device of the present invention, the shape of the hopper and the shape of the charging portion are devised to suppress the formation of bridges due to the granular material and to prevent clogging of the granular material. The granular material filling apparatus of the present invention only needs to include at least one of the hopper and the charging unit, thereby suppressing the formation of bridges due to the granular material and supplying the granular material uniformly to the plurality of reaction tubes. It becomes easy.

  Next, the suitable aspect of a conveyance path is demonstrated in the granular material filling apparatus of this invention.

  When the bottom surface of the conveyance path 2 is constituted by the conveyor 3, the conveyor 3 is constituted by an endless track belt 4 supported by at least two rollers 5, and the belt 4 is conveyed by the rotation of the rollers 5. At this time, in order to make the belt 4 go straight in the downstream direction of the conveyance path 2 without meandering, the back surface (roller side surface) of the belt 4 is provided with a convex portion extending in the circumferential direction of the belt 4, A recess extending in the circumferential direction of the roller 5 is preferably formed on the surface of the roller 5. The convex portion provided on the back surface of the belt 4 is formed so as to fit into the concave portion on the surface of the roller 5. If the belt 4 and the roller 5 are formed in this way, when the belt 4 is conveyed by the roller 5, the belt 4 is less likely to be displaced with respect to the axial direction of the roller 5, and advances straight in the downstream direction of the conveyance path 2. It becomes easy. As a result, the granular material is uniformly conveyed on the conveyance path 2 by the conveyor 3.

  It is preferable that a brush 6 is attached to the conveyor 3 at a portion of the belt 4 that does not constitute the bottom surface of the conveyance path 2 so as to contact the surface of the belt 4. In FIG. 1, a brush 6 is attached to the lower side of the conveyor 3 so as to contact the lower surface of the belt 4. If the brush 6 is attached in this way, when the belt 4 is conveyed by the rotation of the roller 5, the powdery material (powdered material generated by wear of the granular material) attached to the surface of the belt 4 is brushed 6. Is continuously removed. As a result, the formation of deposits on the belt 4 due to moisture absorption of the powdery material is suppressed, and only the granular material is easily supplied to the reaction tube.

  As shown in FIG. 2, it is preferable that a hole 7 is formed on the bottom surface of the conveyance path 2 to screen off the powdery material. When powder is supplied to the reaction tube, the pressure loss in the reaction tube is likely to increase, making it difficult to evenly distribute the pressure loss in multiple reaction tubes, and the reaction efficiency varies from reaction tube to reaction tube. Leading to a decline in the rate. Therefore, by providing the hole 7 through which the powdery material is removed on the bottom surface of the transport path 2, only the granular material is easily supplied to the reaction tube. For example, a punching metal may be employed as the hole 7 through which the powdered material is removed. It is preferable that the hole 7 through which the particulate matter is screened is provided immediately before the particulate matter is introduced into the input unit 21, that is, on the downstream side of the conveyance path 2. Moreover, the hole 7 is formed so as to have an appropriate hole diameter so that not only the powdered material generated by the abrasion of the granular material is screened but also the fragments generated by the crushing of the granular material are screened out. preferable. In FIG. 1, a receiving tray 8 for receiving the powdered material dropped from the hole is provided below the hole 7 through which the powdered material is screened, and the granular material filling apparatus 1 is provided with the receiving tray 8 in this way. Is preferred.

  It is preferable that the conveyance path 2 is formed so that the end portion on the input portion 21 side gradually decreases in width toward the entrance of the input portion 21. In FIG. 2 and FIGS. 6 to 8, the end portion on the input portion 21 side of the transport path 2 is formed in this way. The lower cylinder 24 of the charging unit 21 is preferably the same diameter as the diameter of the reaction tube or a diameter close to that in order to smoothly fill the reaction tube with the granular material from the charging unit 21. When the width of 2 is set in accordance with the diameter of the charging unit 21, the granular material conveying ability of the conveying path 2 cannot be secured sufficiently, and it takes a lot of time for the filling operation of the granular material into the reaction tube. However, if the end of the transport path 2 on the input unit 21 side is formed so that the width gradually decreases toward the entrance of the input unit 21, the amount of the granular material transport in the transport path 2 can be increased. The granular material can be efficiently supplied to the reaction tube. In addition, the granular material can be smoothly introduced from the conveyance path 2 to the input unit 21. The maximum width of the conveyance path 2 is preferably 1.1 times or more, more preferably 1.2 times or more, more preferably 3.0 times or less, and preferably 2.5 times or less of the inner diameter of the upper cylinder 22 of the input unit 21. More preferred.

  Hereinafter, the present invention will be described in more detail with reference to examples. However, the present invention is not limited to the following examples, and appropriate modifications are made within a range that can meet the purpose described above and below. Any of these can be carried out and are included in the technical scope of the present invention.

Preparation of Catalyst Solution A was prepared by dissolving 392 parts of cobalt nitrate and 172 parts of nickel nitrate in 500 parts of ion-exchanged water. Further, 95 parts of ferric nitrate and 137 parts of bismuth nitrate were dissolved in a nitric acid aqueous solution composed of 80 parts of 61% by mass nitric acid and 300 parts of ion-exchanged water to prepare a solution B. Separately, 500 parts of ammonium paramolybdate was added to 1500 parts of heated ion-exchanged water and dissolved with stirring to prepare Solution C. Solution A and solution B were added dropwise to solution C and mixed, and then an aqueous solution in which 2.4 parts of potassium nitrate was dissolved in 40 parts of ion-exchanged water was added to obtain a suspension. The resulting suspension was heated, stirred and evaporated to dryness to give a solid. The solid thus obtained was dried at 150 ° C. and then pulverized to 150 μm or less. An appropriate amount of ammonium nitrate and ion-exchanged water were added to the obtained powder and kneaded to obtain a paste-like substance. This pasty substance was molded into a ring shape having an outer diameter of 8 mm, an inner diameter of 2 mm, and a length of 8.8 mm, and calcined at 470 ° C. for 8 hours under air flow to obtain a catalyst. The metal element composition excluding oxygen of this catalyst was Mo ₁₂ Bi _1.2 Fe ₁ Co _5.7 Ni _2.5 K _0.1 .

Test example 1
The catalyst prepared as described above was charged into a reaction tube of a fixed bed multitubular reactor using the granular material filling apparatus shown in FIGS. As shown in FIG. 3 and FIG. 4, the hopper of the granular material filling apparatus is inclined such that the rear side wall is positioned on the downstream side of the conveying path from above and the rear side wall is formed in a V-shaped horizontal section. It had been. The rear side wall was inclined at an angle of 62 °. As shown in FIG. 6, the insertion portion is connected to the lower cylinder having a small diameter on the lower side of the upper cylinder having a large diameter while the axis of the upper cylinder is shifted from the conveyance path from the axis of the lower cylinder. It was formed to be located on the distal side. At this time, the upper cylinder had an inner diameter of 27 mmφ, and the lower cylinder had an inner diameter of 21 mmφ. The fixed bed multitubular reactor was equipped with 11,000 reaction tubes having an inner diameter of 25 mm and a length of 3000 mm.

  The granular material filling apparatus used all eight conveying paths, and charged the catalyst into eight reaction tubes at the same time. Each hopper was charged with 1 L of catalyst, and the catalyst was supplied to the corresponding reaction tube with a transfer time of 30 seconds. After the eight reaction tubes were filled with the catalyst, another eight reaction tubes were filled with the catalyst in the same manner, and this catalyst filling operation was repeated 25 times to fill the 200 reaction tubes with the catalyst.

  In Test Example 1, no bridging by the catalyst occurred in the hopper and the charging part. After filling the reaction tube with the catalyst, the layer length (packed layer length) of the catalyst filled in the reaction tube and the pressure loss of the reaction tube were measured. As a result, the packed bed length distribution was in the range of ± 2% of the average packed bed length, and the pressure loss distribution was in the range of ± 3% of the average pressure loss.

Test example 2
As shown in FIG. 7, the input portion is the same as in Test Example 1 except that the input portion formed so that the axis of the upper cylinder is located closer to the proximal side than the axis of the lower cylinder as shown in FIG. The catalyst was charged into the reaction tube. Note that the inner diameters of the upper and lower cylinders of the charging portion were the same as those in Test Example 1.

  In Test Example 2, no bridging occurred in the hopper, but bridging was likely to occur in the charging part. However, no bridging occurred in the charging section by continuing the filling with light sticking with the stick. After packing the catalyst into the reaction tube, the packed bed length and pressure loss of the reaction tube were measured. As a result, the distribution of packed bed length was within ± 3% of the average packed bed length, and the distribution of pressure loss was the average pressure loss. Of ± 4%.

Test example 3
As shown in FIG. 8, the same as in Test Example 1 except that an input portion formed so that the axis of the upper cylinder is positioned on the left side or the right side as viewed from the conveyance path as shown in FIG. The catalyst was charged into the reaction tube. Note that the inner diameters of the upper and lower cylinders of the charging portion were the same as those in Test Example 1.

  In Test Example 3, no bridging occurred in the hopper, but bridging was likely to occur in the charging part. However, no bridging occurred in the charging section by continuing the filling with light sticking with the stick. As a result of measuring the packed bed length and pressure loss of the reaction tube after filling the catalyst into the reaction tube, the packed bed length distribution is within ± 2% of the average packed bed length, and the pressure loss distribution is the average pressure loss. Of ± 4%.

Test example 4
As shown in FIG. 9, the catalyst was filled into the reaction tube in the same manner as in Test Example 1 except that a hopper having a flat rear wall (horizontal cross-sectional shape) was used.

  In Test Example 4, a bridge was generated near the lower openings of the five hoppers in the first catalyst filling operation. Therefore, although the catalyst was urged with a spatula to urge the catalyst to be discharged, the discharge time of the catalyst to the conveying path varied. Further, a total of 25 catalyst filling operations were performed, and in each case, a bridge was formed by a plurality of hoppers. Note that no bridging occurred in the charging section. As a result of measuring the packed bed length and pressure loss of the reaction tube after filling the catalyst into the reaction tube, the distribution of packed bed length is within ± 4% of the average packed bed length, and the distribution of pressure loss is the average pressure loss. Of ± 9%.

Test Example 5
As shown in FIG. 10, the reaction tube was filled with the catalyst in the same manner as in Test Example 1 except that the input portion was formed so that the axis of the upper cylinder and the axis of the lower cylinder coincided as shown in FIG. . Note that the inner diameters of the upper and lower cylinders of the charging portion were the same as those in Test Example 1.

  In Test Example 5, no bridge occurred in the hopper, but a bridge sometimes formed in the charging portion. Although filling was performed while lightly pushing the charging portion with a stick, formation of the bridge could not be suppressed. Therefore, the work was continued by temporarily stopping the conveyor on the transport path and removing the bridge at the charging section, and then restarting the filling. However, extra work time was required for interruption. As a result of measuring the packed bed length and pressure loss of the reaction tube after filling the catalyst into the reaction tube, the distribution of packed bed length is within ± 5% of the average packed bed length, and the distribution of pressure loss is the average pressure loss. Of ± 11%.

  The granular material filling apparatus of the present invention can be used to fill each reaction tube of a fixed bed multitubular reactor with a granular material such as a catalyst.

1: Granular material filling device 2: Conveyance path 3: Conveyor 11: Hopper 12: Rear side wall 13: Front side wall 21: Loading part 22: Upper cylinder 24: Lower cylinder

Claims (7)

A granular material filling device for supplying granular materials to each reaction tube of a fixed bed multitubular reactor,
A plurality of hoppers arranged in parallel;
Each having a transport path provided on the exit side of each hopper,
The hopper has a rear side wall located on the upstream side of the conveyance path, and the rear side wall is inclined so that the lower side is located on the downstream side of the conveyance path from above and is normal to the inside of the hopper The granular material filling apparatus, wherein a projection vector L of the vector H onto the conveyance path has a portion that is not parallel to the downstream direction of the conveyance path.   The granular material filling apparatus according to claim 1, wherein the hopper has a front side wall positioned substantially downstream of the conveyance path.   The granular material filling device according to claim 1 or 2, wherein the rear side wall is formed in a V-shaped or U-shaped horizontal section. A granular material filling device for supplying granular materials to each reaction tube of a fixed bed multitubular reactor,
A plurality of hoppers arranged in parallel;
A transport path provided on the exit side of each hopper;
Each having a loading section provided on the exit side of each conveyance path,
The granular material filling apparatus, wherein the charging portion is formed by connecting a lower cylinder having a small diameter to a lower side of an upper cylinder having a large diameter while shifting an axis.   The hopper has a rear side wall located on the upstream side of the conveyance path, and the rear side wall is inclined so that the lower side is located on the downstream side of the conveyance path from above and is normal to the inside of the hopper The granular material filling device according to claim 4, wherein a projection vector L of the vector H onto the conveyance path has a portion that is non-parallel to the downstream direction of the conveyance path.   The granular material filling device according to claim 4 or 5, wherein an axis of the upper cylinder is located distal to the axis of the lower cylinder as viewed from the conveyance path.   The granular material filling device according to any one of claims 4 to 6, wherein a hole through which a powdery material is removed is formed on a bottom surface of the conveyance path.

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