WO2007086610A1

WO2007086610A1 - Bubble column type hydrocarbon synthesis reactor

Info

Publication number: WO2007086610A1
Application number: PCT/JP2007/051845
Authority: WO
Inventors: Osamu Wakamura; Yuzuru Kato; Eiichi Yamada; Yasuhiro Onishi; Yasuyuki Osawa
Original assignee: Nippon Steel Engineering Co., Ltd.
Priority date: 2006-01-30
Filing date: 2007-01-30
Publication date: 2007-08-02
Also published as: JP2007197636A

Abstract

The bubble column type hydrocarbon synthesis reactor synthesizes hydrocarbons by a chemical reaction of a gas whose main components are hydrocarbon and carbon monoxide, and a slurry having solid catalyst particles suspended in a liquid, including: a reactor main body for accommodating the slurry; a reaction gas-feeding portion that is disposed at the lower part of the reactor main body and feeds the gas into the slurry; a separator that is extendedly provided along the height direction of the reactor main body and divides a space in the interior of the reactor main body into a plurality of areas.

Description

DESCRIPTION

BUBBLE COLUMN TYPE HYDROCARBON SYNTHESIS REACTOR

TECHNICAL FIELD

The present invention relates to a bubble column type hydrocarbon synthesis reactor, and in particular to a reactor that carries out a Fischer-Tropsch synthesis reaction by introducing a synthesis gas into a slurry having solid catalyst particles suspended in a liquid hydrocarbon. The present application claims priority to Japanese Patent Application No.

2006-20655 filed on January 30, 2006, the entire contents of which are incorporated herein for reference.

BACKGROUND ART As one of the reaction systems of a Fischer-Tropsch synthesis reaction

(hereinafter called FT reaction) that generates a hydrocarbon compound and water by catalytic reaction from a synthesis gas which is mainly composed of hydrogen and carbon monoxide, a bubble column type slurry phase FT reaction system that carries out an FT reaction by introducing a synthesis gas into a slurry in which solid catalyst particles are suspended in a liquid hydrocarbon is available. Further, a hydrocarbon compound synthesized by the FT reaction is mainly utilized as a raw material for a fuel oil and lubricant oil.

In an FT reactor used for the bubble column type slurry phase FT reaction system, it is necessary to equally disperse catalyst particles in a liquid hydrocarbon in the reactor in order to keep the reaction temperature uniform inside the reactor. However, since it is usual for the specific gravity of the catalyst particles to be heavier than that of the liquid hydrocarbon, there is a tendency the catalyst particles to be unevenly distributed and accumulated in the vicinity of the bottom of the reactor. On the other hand, in a bubble column type FT reactor in which a synthesis gas is introduced from the bottom of the reactor, an ascending flow (air lift) is generated upward of the reactor by a rise of the introduced gas through the slurry, thereby catalyst particles which tend to be unevenly distributed in the vicinity of the bottom of the reactor may be relatively dispersed into the slurry to some extent; however, there is a problem; that the catalyst particles are not sufficiently diffused when the synthesis gas is introduced at a low flow rate.

A technology has been proposed as solving means of such a problem, by which a pipe-shaped downward tube of a so-called "downcomer" is provided in the interior of a reactor to generate a descending flow of slurry inside the downcomer by utilizing the characteristics of an FT reactor in which gas will flow upward due to a smaller specific gravity and liquid in the slurry will flow downward due to a greater specific gravity, thereby promoting an air lift effect based on a synthesis gas introduced into the slurry (for example, refer to specifications of US Patent No. 6,201,031, US Patent No. 5,866,621 and US Patent No. RE 37,229, and PCT International Publication No. WO94/14536). Meanwhile, where the pipe-shaped downcomer as described in the above patent documents is used, it is usually necessary to provide a FT reactor with cooling tubes for removing heat generated by the FT synthesis reaction. However, when a pipe-shaped downcomer is installed in the interior of the reactor (at the middle part of the cross-section of the reactor, in particular), cooling tubes cannot be disposed at a site where the downcomer is to be installed and, therefore, the cooling tubes cannot be arranged evenly. Thus, a problem is posed in that heat generated by the FT reaction cannot be removed effectively and evenly, the temperature of the slurry cannot be kept uniform in the interior of the reactor, and hydrocarbon as a product may not be stable in composition. There is also a problem in that the arrangement of cooling tubes may be complicated, depending on the size of the downcomer.

It is also necessary to provide a member for supporting the downcomer in the interior of the reactor when the above-described downcomer is installed. Therefore, there is another problem in that the structure inside the reactor is complicated due to the necessity of avoiding possible interference between the supporting member and the cooling tubes, thereby making the installation difficult.

The present invention was developed in view of such problems. It is, therefore, an object of the present invention to uniformly disperse catalyst particles in the slurry, keeping uniform the temperature of the slurry in the interior of the reactor and also simplifying the structure inside the reactor, thereby providing an easy installation in a bubble column type hydrocarbon synthesis reactor that carries out a Fischer-Tropsch synthesis reaction.

DISCLOSURE OF THE INVENTION

The inventor et al. found, based on earnest research and study to solve the above-described problems, that a separator can be installed inside a reactor by utilizing the characteristics that an ascending flow of slurry is generated in the vicinity of the center axis of the reactor and a descending flow of slurry is generated near the inner wall of the reactor, thereby generating the descending flow of slurry in an area (circulating area) between the separator and the inner wall of the reactor to promote an air lift effect by introduced gas, and completed the present invention based on the knowledges. That is, a bubble column type hydrocarbon synthesis reactor according to the present invention synthesizes hydrocarbons by a chemical reaction of a gas whose main components are hydrogen and carbon monoxide, and a slurry having solid catalyst particles suspended in liquid, and includes: a reactor main body for accommodating the slurry; a reaction gas-feeding portion that is disposed at the lower part of the reactor main body and feeds the gas into the slurry; and a separator that is provided along the height direction of the reactor main body to divide a space in the interior of the reactor main body into a plurality of areas.

At least one of the plurality of areas is formed so as to be in contact with the inner wall surface of the reactor main body, the separator is disposed in such a way that the slurry can be communicated between the plurality of areas and the separator is also disposed in such a way that the slurry can generate mainly a descending flow at an area which is in contact with the inner wall surface of the reactor main body among the plurality of areas. In the bubble column type hydrocarbon synthesis reactor according to the present invention, the separator may be disposed so that the upper end of the separator is located at a position lower than the liquid level of the slurry, when a chemical reaction is carried out by the gas contact with the slurry in the interior of the reactor main body.

In the bubble column type hydrocarbon synthesis reactor according to the present invention, the separator may be divided in the height direction of the reactor main body.

The bubble column type hydrocarbon synthesis reactor according to the present invention may be further provided with a rectifying member which is disposed in the vicinity of the lower end of the separator to adjust the flow direction of the slurry and that of bubbles of the gas. A method for operating the bubble column type hydrocarbon synthesis reactor according to the present invention is a method for operating a bubble column type hydrocarbon synthesis reactor which synthesizes hydrocarbons by a chemical reaction of a gas whose main components are hydrogen and carbon monoxide, and a slurry having solid catalyst particles suspended in liquid, including: a step in which the slurry is fed into the reactor main body for accommodating the slurry until the liquid level of the slurry is higher than the upper end of the separator; and a step in which the gas is fed into the slurry accommodated inside the reactor main body.

According to the bubble column type hydrocarbon synthesis reactor of the present invention, a descending flow of slurry is generated in an area formed so as to be along the inner wall surface of the reactor main body among a plurality of areas in the interior of the reactor main body divided by the separator, and an ascending flow of slurry is generated at other areas. Thereby, an air lift effect is promoted by a gas introduced into the reactor and catalyst particles can be evenly dispersed in the slurry. As a result, the temperature of the slurry inside the reactor can be kept uniform to stabilize compositions of the hydrocarbon products.

Also, according to the bubble column type hydrocarbon synthesis reactor of the present invention, since it is possible to evenly dispose cooling tubes in a reaction area in the interior of the reactor, heat generated from the reaction can be removed effectively and evenly, thereby keeping uniform the temperature of the slurry in the reaction area. Therefore, the composition of the hydrocarbon product can be stabilized. Further, the cooling tubes can be arranged in a simple manner, thereby making it possible to simplify the structure inside the reactor and make the installation easy.

Still further, according to the bubble column type hydrocarbon synthesis reactor of the present invention, since the interior of the reactor is made simpler in structure as compared with the installation of a pipe-shaped downcomer, the interior of the reactor ,

O

can be made simpler in structure to make the installation easy. Thereby, the production cost can be reduced more.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a longitudinal sectional view showing the entire configuration of an

FT reactor according to Embodiment 1 of the invention.

FIG. 2 is an enlarged longitudinal sectional view showing major parts of the FT reactor depicted in FIG. 1.

FIG. 3 is a cross sectional view showing the FT reactor depicted in FIG. 2, which is taken along the line a-a.

FIG. 4 is a cross sectional view showing a first modified version of the FT reactor depicted in FIG. 3.

FIG. 5 is a cross sectional view showing a second modified version of the FT reactor depicted in FIG. 3. FIG. 6 is a longitudinal sectional view showing the constitution of the major parts of the FT reactor according to Embodiment 2 of the present invention.

FIG. 7 is a cross sectional view showing the FT reactor depicted in FIG. 6, which is taken along the line b-b.

FIG. 8 is a cross sectional view showing the FT reactor depicted in FIG. 6, which is taken along the line c-c.

BEST MODES FOR CARRYING OUT THE INVENTION A detailed description is given of a preferred embodiment of the invention with reference to the accompanying drawings. In the specification and the drawings, components that are substantially identical to each other in function and configuration are given the same reference numerals, and overlapping description thereof is omitted. (Embodiment 1)

First, based on FIG. 1, a description is given of a bubble column type slurry phase FT synthesis reactor (hereinafter merely called an FT reactor) 1 that is one example of a bubble column type hydrocarbon synthesis reactor according to Embodiment 1 of the invention.

As shown in FIG. 1, the FT reactor 1 according to the present embodiment is mainly provided with a reactor main body 10, a distributor 20, a cooling tube 40, a separator 50 and a rectifying plate 60. The reactor main body 10 is a roughly cylindrical vessel made of metal, the diameter of which is 1 to 20 meters, preferably 2 to 10 meters, and the height of which is 10 to 50 meters, preferably 15 to 45 meters. Slurry 12 having solid catalyst particles 124 suspended in a liquid hydrocarbon (product of the FT reaction) 122 is accommodated in the interior of the reactor main body 10. The distributor 20 is one example of the reaction gas-feeding portion according to the present embodiment. The distributor 20 is disposed at the lower part in the interior of the reactor main body 10 and feeds a synthesis gas, the main components of which are hydrogen and carbon monoxide, into the slurry 12. The distributor 20 is provided with a synthesis gas feeding pipe 22, a nozzle header 24 attached to the distal end part of the synthesis gas feeding pipe 22 and a plurality of synthesis gas feeding nozzles 26 attached to the side part of the nozzle header 24.

The synthesis gas fed externally through the synthesis gas feeding pipe 22 passes through the interior of the nozzle header 24 and is jetted into the slurry 12 in the interior of the reactor main body 10, for example, downward (that is, the direction shown by the thin arrow in the drawing) from a synthesis gas feeding port (not shown) secured at the _o

lower part of the synthesis gas feeding nozzle 26 (the bottom part side of the reactor main body 10). Thus, the synthesis gas introduced from the distributor 20 into the slurry 12 is made into bubbles 28 and drifts from bottom to the top toward the height direction (the perpendicular direction) of the reactor main body 10 in the slurry 12. In the process, the synthesis gas is dissolved in the liquid hydrocarbon 122 and brought into contact with the catalyst particles 124, whereby a synthesis reaction of the liquid hydrocarbon (FT synthesis reaction) is carried out. It is to be noted that in the present embodiment, the synthesis gas is jetted downward, but the synthesis gas may be jetted upward of the reactor main body 10. Still further, the synthesis gas is introduced from the distributor 20, which is disposed at the lower part of the interior of the reactor main body 10, into the slurry 12, and the synthesis gas thus introduced is made into bubbles 28 and rised upward in the interior of the reactor main body 10, whereby in the interior of the reactor main body 10, an ascending flow (air lift) of the slurry 12 is generated at the middle part of the cross-section of the reactor main body 10 and in the vicinity thereof (that is, in the vicinity of the center axis of the reactor main body 10), and a descending flow of the slurry 12 is generated near the inner wall of the reactor main body 10 (that is, near the inner-circumferential portion). Thereby, as shown by the thick arrows in FIG. 1, a circulating flow of the slurry 12 is generated in the interior of the reactor main body 10. The cooling tube 40 is provided along the height direction of the reactor main body 10 in the interior of the reactor main body 10 and cools the slurry 12, whose temperature is raised due to heat generated by the FT synthesis reaction. The cooling tube 40 may be formed so as to reciprocate a plurality of times (for example, reciprocates two times in FIG. 1) vertically in the perpendicular direction by bending a single tube as shown in, for example, FIG. 1. However, the shape and number of _g

cooling tubes are not limited to the above-described shape and number, but may be such that the cooling tubes are evenly disposed in the interior of the reactor main body 10 and contribute to uniform cooling of the slurry 12. For example, a plurality of cooling tubes having a double-tube structure of a so-called bayonet type may be installed in the interior of the reactor main body 10.

Cooling water (for example, the temperature of which is different by -50 through O⁰C from the interior temperature of the reactor main body 10) introduced from the cooling tube inlet 42 is caused to circulate in the cooling tube 40. By exchanging heat between the cooling water and the slurry 12 via the tubular wall of the cooling tube 40 in the process during which the cooling water circulates in the cooling tube 40, the slurry 12 in the interior of the reactor main body 10 is cooled down. A part of the cooling water is discharged from the cooling tube outlet 44 as steam. In addition, the medium for cooling the slurry 12 is not limited to the cooling water as described above, but, for example, a straight chain, branched-chain and annular paraffin, olefin, low-molecular-weight silane, silyl ether, and silicone oil, etc., of C4 through ClO may be used as the medium.

The separator 50 is extendedly provided in the interior of the reactor main body 10 along the height direction of the reactor main body 10, dividing a space in the interior of the reactor main body 10 into a plurality of areas, hi the present embodiment, the space in the interior of the reactor main body 10 is divided in such a way that a reaction area generating an ascending flow of the slurry 12 can communicate with a circulating area generating a descending flow of the slurry 12. In this instance, the circulating area (the area where the descending flow of the slurry 12 given by the downward arrow in FIG. 1 is generated) is formed near the inner wall in the interior of the reactor main body 10. Further, a cooling tube 40 is disposed in the reaction area (the area where the ascending flow of the slurry 12 given by the upward arrow in FIG. 1 is generated). The separator 50 will be described in detail later.

The rectifying plate 60 is one example of the rectifying member according to the present invention and is disposed in the vicinity of the lower end of the separator 50 to adjust the flow direction of the slurry 12 and that of bubbles of the synthesis gas. More specifically, the descending flow generated in the circulating area is guided to be directed toward the reaction area. The rectifying plate 60 is formed in such a way that the cross section of the reactor main body 10 in the direction vertical to the height direction (the horizontal direction) is roughly in a crescent shape enclosed, for example, by a circular arc which is in contact with the inner wall surface of the reactor main body 10 and the chord thereof. However, the rectifying plate may be available in any shape, as long as the descending flow of the slurry 12 at the circulating area can be guided to be directed toward the reaction area. For example, the cross-section of the rectifying plate in the horizontal direction may be formed roughly in a ring shape. The rectifying plate 60 will also be described in detail later.

Next, a detailed description will be made for constitutions and effects of the separator 50 and the rectifying plate 60 in the present embodiment by referring to FIG. 2 and FIG. 3.

As described above, the separator 50 divides a space in such a way that a reaction area R generating the ascending flow of the slurry 12 and a circulating area C generating the descending flow of the slurry 12 can circulate each other. In the present embodiment, as shown in FIG. 2 and FIG. 3, the reaction area R is formed at the middle part of the cross-section of the reactor main body 10 and in the vicinity thereof, and the circulating area C is formed near the inner wall of the reactor main body 10. More specifically, the separator 50 is a dividing plate composed of two flat plates disposed near _π

the inner wall of the reactor main body 10. The reaction area R of the present embodiment is formed as an area enclosed by two separators 50 and the inner wall of the reactor main body 10 at the middle part of the cross-section of the reactor main body 10 and in the vicinity thereof. The circulating area C of the present embodiment is formed as an area enclosed by one separator 50 and the inner wall of the reactor main body 10 near the inner wall of the reactor main body 10. In this instance, two circulating areas C are disposed so as to face each other across the center axis of the reactor main body 10.

Further, the shape and number of the separators are not limited to the above-described dividing plate composed of two flat plates. The separator may be provided in any number and any shape, as long as it divides the space in such a way that the reaction area R is formed at the middle part of the cross-section of the reactor main body 10 and in the vicinity thereof and the circulating area C is formed near the inner wall in the interior of the reactor main body 10.

For example, as shown in FIG. 4, a roughly square hollow rod-shaped separator 510 may be disposed so that the four corners thereof are in contact with the inner wall of the reactor main body 10. In this instance, a reaction area R enclosed by the four side surfaces of the separator 510 is formed at the middle part of the cross-section of the reactor main body 10 and in the vicinity thereof, whereas four circulating areas C enclosed by one side surface of the separator 510 and the inner wall of the reactor main body 10 are formed near the inner wall in the interior of the reactor main body 10.

Alternatively, as shown in FIG. 5, a roughly cylindrically shaped separator 520 may be disposed on the inner wall side of the reactor main body 10 so as to provide a double-tube structure. In this instance, a reaction area R enclosed by the separator 520 is formed at the middle part of the cross-section of the reactor main body 10 and in the vicinity thereof, whereas one ring-shaped circulating area C enclosed by the outer wall of the separator 520 and the inner wall of the reactor main body 10 is formed near the inner wall of the reactor main body 10.

As described above, the reaction area R generating an ascending flow of the slurry 12 is formed at the middle part of the cross-section of the reactor main body 10 and in the vicinity thereof and the circulating area C generating a descending flow of the slurry 12 is formed near the inner wall of the reactor main body 10, whereby the circulating area C acts as a downcomer. Thereby, an ascending flow of slurry is generated at the middle part of the cross-section of the reactor and in the vicinity thereof, and a descending flow of slurry is generated near the inner wall of the reactor by utilizing the characteristics of a bubble column type FT reactor, thus making it possible to promote an air lift effect based on a synthesis gas introduced into the slurry in the interior of the reactor. Therefore, catalyst particles can be evenly dispersed into the slurry, by which the temperature of the slurry inside the reactor can be kept uniform and the composition of the hydrocarbon product can be stabilized. When the FT reaction is carried out in the interior of the reactor main body 10, it is preferable that the separator 50 be formed in such a way that the upper end thereof is placed near the upper surface (liquid level) of the slurry 12 in the interior of the reactor main body 10 and the lower end thereof be kept close to the vicinity of the bottom of reactor main body 10. It is, thereby, possible to sufficiently promote the air lift effect. In operating the FT reactor 1 described in the present embodiment, at first, the slurry 12 is fed into the reactor main body 10 until the upper surface (liquid level) is higher than the upper end of the separator 50, and a synthesis gas is, thereafter, fed into the slurry 12 accommodated in the reactor main body 10. When the FT reaction is carried out in the interior of the reactor main body 10, it is necessary for the upper end of the separator 50 to be lower than the upper surface of the slurry 12. When the upper ^

end of the separator 50 is higher than the upper surface of the slurry 12, the slurry 12 is prevented from flowing from the reaction area R to the circulating area C, resulting in a failure of promoting the air lift effect.

Further, as described above, the cooling tube 40 is disposed in the reaction area R. In the present embodiment, the separator 50 (the separator 510 or 520) is disposed near the inner wall of the reactor main body 10, unlike a conventional reactor in which a pipe-shaped downcomer is provided at the middle part of the reactor main body 10. Therefore, since there are no downcomers which prevent disposing of the cooling tubes 40 at the middle part of the cross-section of the reactor main body 10 and in the vicinity thereof, the cooling tubes 40 can be evenly disposed in the reaction area R in the interior of the reactor main body 10. It is, thus, possible to remove heat generated by the FT reaction carried out in the interior of the reactor main body 10 effectively and evenly and also keep the temperature of the slurry 12 uniform in the interior of the reactor main body 10. As described so far, according to the FT reactor 1 of the present embodiment, the temperature of the slurry 12 can be kept constant and free of temperature difference depending on the site where the reaction is carried out, thereby making it possible to stabilize the composition of the hydrocarbon product.

Further, where the cooling tube 40 is a cooling tube group which is constituted of two or more cooling tubes, major cooling tubes included in the cooling tube group may be formed in the reaction area R and remaining cooling tubes may be formed in the circulating area.

Still further, the FT reactor 1 of the present embodiment eliminates the necessity of providing a conventional pipe-shaped downcomer or a supporting member for supporting the downcomer in the interior of the reactor main body 10, whereby the reactor can be simplified in internal structure and installed easily, as compared with the ^

installation of the pipe-shaped downcomer. Thereby, the production cost can also be reduced more.

In addition, as described above, the FT reactor 1 of the present embodiment is provided in the vicinity of the lower end of the separator 50 in the reactor main body 10 with a rectifying plate 60 for guiding to direct the descending flow of the slurry 12 in the circulating area C toward the reaction area R. The rectifying plate 60 as a rectifying member of the present invention is formed so that the cross-section in the horizontal direction is roughly in a crescent shape enclosed by a circular arc which is in contact with the inner wall surface of the reactor main body 10 and the chord thereof. It is, however, preferable that the chord of the above-described roughly crescent-shaped rectifying plate 60 be located nearer at the middle part of the reactor main body 10 than the separator 50 in view of a fact that a rectifying effect of the rectifying plate 60 (effect of promoting the flow of the slurry 12 from the circulating area C to the reaction area R) and an air lift promoting effect are exerted sufficiently. Further, a relative distance (relative position) between the lower end of the separator 50 and the rectifying plate 60 can be adjusted to control the flow rate of the slurry 12 running from the circulating area C to the reaction area R. The inventor et al. have experimentally confirmed that in the present embodiment, when a distance between the lower end of the separator 50 and the rectifying plate 60 is reduced to about 1/10 of the diameter of the reactor main body 10, for example, the rectifying plate 60 is able to exert a sufficient rectifying effect.

The rectifying plate 60 also acts to block an ascending flow of the slurry 12 from its downward. Thereby, a descending flow of the slurry 12 at the circulating area C is not prevented from flowing by an ascending flow of the slurry 12 from below the rectifying plate 60, making it possible to exert a sufficient rectifying effect. It is, thus, ^

possible to improve an air lift effect based on an introduced synthesis gas and also disperse catalyst particles 124 into the slurry 12 more uniformly. (Embodiment 2)

Next, a description will be made for the constitution and effect of the FT reactor 2 according to Embodiment 2 of the present invention by referring to FIG. 6 through FIG. 8.

Embodiment 2 of the present invention is an example where separators are provided in a plurality of stages divided in the height direction of the reactor main body 10. In the present embodiment, the separator is divided in the height direction of the reactor main body 10. More specifically, the separator is divided into two portions, namely a first separator 501 disposed at the upper part of the reactor main body 10 and a second separator 502 disposed at the lower part thereof. However, the number of the separators is not limited, in particular, and may be decided in accordance with the height of the reactor main body 10. Therefore, for example, where the height of the reactor main body 10 is high, the separator may be provided in three or more divisions in the height direction of the reactor main body 10.

As described above, the separator is provided in a divided manner in the height direction of the reactor main body 10, thereby making it possible to provide a descending flow of the slurry 12 by using a separator at a lower stage (the second separator 502 in the present embodiment) even in a case where the liquid level of the slurry 12 is decreased to be lower than the upper end of the separator at an upper stage (the first separator 501 in the present embodiment) on operation of the FT reactor 2 when the quantity of the slurry 12 is reduced, or the quantity of the synthesis gas flow rate is reduced. Further, the separator is provided in a divided manner in the height direction of _{Λ r}

16

the reactor main body 10, thereby making it possible to make smaller individual separators (separators 501 and 502 in the present embodiment) and fabricate the separators easily.

The inventor et al. estimate that where the reactor main body 10 is long in the perpendicular direction (the reactor main body is high) and the separator is provided only at one stage, an air lift effect based on an introduced synthesis gas is decreased, due to an excessive length of the reaction area R in the perpendicular direction, to result in difficulty in circulating the slurry 12. However, the inventor et al. consider that as described in the separators 501 and 502 according to the present embodiment, the separator is provided in a divided manner in the height direction of the reactor main body 10, whereby each reaction area R divided by the separator is made short in the perpendicular direction and the above-described air lift effect is, therefore, not decreased.

As shown in FIG. 6 to FIG. 8, the upper separator 501 and the lower separator 502 may be disposed, with these separators deviated at 90 degrees. Therefore, a plurality of separators are disposed, with the separators deviated at a predetermined angle, thereby providing an effect that slurry can flow smoothly at sites where the separators are divided to result in promoting descending flow of the slurry 12 in the circulating area C.

Further, as with the FT reactor 1 according to Embodiment 1 described previously, the FT reactor 2 of the present embodiment may also be provided with a rectifying plate. In this instance, for example, a first rectifying plate (upper rectifying plate) 601 may be provided at an upper separator 501, and a second rectifying plate (lower rectifying plate) 602 may be provided at a lower separator 502.

As described above, the rectifying plate is provided at each of the divided separators, thereby allowing the rectifying plate to exert a sufficient rectifying effect and increasing further an air lift effect based on an introduced synthesis gas to diffuse more _{χ η}

uniformly catalyst particles 124 in the slurry 12.

A description has been given so far of preferred embodiments of the present invention by referring to the attached drawings. It is a matter of course that the present invention is not limited to the above-described embodiments. It is obvious that various types of modifications and variations are conceivable by one skilled in the same art in the category described in the scope of claims of the present invention. Therefore, it is to be understood that such various types of modifications and variations naturally belong to the technical scope of the present invention.

For example, in the above-described embodiment, the shape of the reactor main body 10 is roughly cylindrical. However, the shape of the reactor main body is not limited in particular, as long as the reaction area is formed at the middle part of the cross-section of the reactor main body and in the vicinity thereof, the circulating area is formed near the inner wall of the reactor main body, and an air lift effect of the synthesis gas introduced by utilizing the characteristics of the bubble column type FT reactor can be promoted.

Further, in the above-described embodiment, the cooling tube 40 is formed so as to reciprocate a plurality of times vertically along the perpendicular direction by bending a single tube. However, as long as the tube is evenly disposed in the reaction area in the interior of the reactor main body and contributes to uniform cooling of the slurry, the shape and number of cooling tubes are not limited in particular. For example, a plurality of double-tube structure cooling tubes of a so-called "bayonet type" may be disposed in the interior of the reactor.

Additionally, in the above-described embodiment, rectifying plates 60, 601 and 602 are provided respectively in the vicinity of the lower ends of separators 50, 501 and 502. The rectifying plate is not necessarily provided. However, it is preferable to provide the rectifying plate in promoting further an air lift effect as described above.

INDUSTRIAL APPLICABILITY

The present invention is applicable to a bubble column type hydrocarbon synthesis reactor, and in particular to a reactor for carrying out a Fischer-Tropsch synthesis reaction by introducing a synthesis gas into a slurry having solid catalyst particles suspended in a liquid hydrocarbon.

Claims

1. A bubble column type hydrocarbon synthesis reactor for synthesizing hydrocarbons by a chemical reaction of a gas whose main components are hydrogen and carbon monoxide, and a slurry having solid catalyst particles suspended in a liquid, comprising: a reactor main body for accommodating the slurry; a reaction gas-feeding portion that is disposed at the lower part of the reactor main body and feeds the gas into the slurry; and a separator that is extendedly provided along the height direction of the reactor main body and divides a space in the interior of the reactor main body into a plurality of areas; wherein at least one of the plurality of areas is formed so as to be in contact with the inner wall surface of the reactor main body, the separator is disposed in such a way that the slurry can circulate among the plurality of areas, and the separator is also disposed in such a way that the slurry can mainly generate a descending flow in an area which is in contact with the inner wall surface of the reactor main body among the plurality of areas.

2. The bubble column type hydrocarbon synthesis reactor according to Claim 1, wherein the separator is disposed so that the upper end of the separator is located at a position lower than the liquid level of the slurry when a chemical reaction is carried out by the gas contact with the slurry in the interior of the reactor main body.

3. The bubble column type hydrocarbon synthesis reactor according to Claim 1 , wherein the separator is divided in the height direction of the reactor main body.

4. The bubble column type hydrocarbon synthesis reactor according to Claim 1, which is further provided with a rectifying member disposed in the vicinity of the lower end of the separator to adjust the flow direction of the slurry and that of bubbles of the gas.

5. A method for operating the bubble column type hydrocarbon synthesis reactor which synthesizes hydrocarbons by a chemical reaction of a gas whose main components are hydrogen and carbon monoxide, and a slurry having solid catalyst particles suspended in a liquid, comprising: a step in which the slurry is fed into the reactor main body for accommodating the slurry until the liquid level of the slurry is higher than the upper end of the separator; and a step in which the gas is fed into the slurry accommodated inside the reactor main body.