JP5545799B2 - Olefin polymerization reaction apparatus, polyolefin production system, and polyolefin production method - Google Patents

Description

  The present invention relates to an olefin polymerization reaction apparatus and a polyolefin production system using a spouted bed, and a method for producing polyolefins such as polyethylene and polypropylene using these.

  2. Description of the Related Art Conventionally, an olefin polymerization reaction apparatus is known that polymerizes an olefin monomer supplied as a gas or liquid in a container in the presence of a catalyst to form granular polyolefin particles. However, since the polyolefin particles are almost completely mixed in one container, short paths through which particles that are not sufficiently grown are discharged and particles that have grown too much are likely to accumulate in the container.

  In this case, the structural uniformity of the produced particles is poor, the catalyst cost is increased, the catalyst residue is increased, and defects in the molded product obtained by molding a multistage polymer obtained by polymerization in multiple reaction regions (Since it resembles the shape of a fish eye, it is called “fish eye”.) Problems such as an increase are likely to occur. In addition, in the case of complete mixing, when performing polymerization of different lots by changing the polymerization conditions, it takes time to completely discharge the polymerized polyolefin particles before changing the conditions, so that non-standard products A large amount will be generated. On the other hand, it is conceivable to connect a plurality of completely mixed type devices in series to form a plug flow as a whole, but it is expensive to install a large number of devices in series. Therefore, in one apparatus, it is required to make the plug flow by reducing the residence time distribution. As such an apparatus, apparatuses as disclosed in Patent Documents 1 to 3 are known.

  On the other hand, devices such as Patent Documents 4 to 10 and Non-Patent Document 1 are known as devices that have various improvements using a fluidized bed. Among such apparatuses, when apparatuses such as Patent Documents 4 to 6 and Non-Patent Document 1 are used, a region where the gas composition is different in the region where the polyolefin particles circulate is partially compared with other regions. By providing it, it is said that polyolefin with wide molecular weight distribution and copolymer composition distribution can be produced.

  By the way, although it is not the field of polyolefin manufacture, the technique of making a solid particle and a fluid contact using the flow called a spouted bed is known (refer nonpatent literature 2). Moreover, the technique which uses a draft tube as a stabilization plan of a spouted bed is also known (refer patent documents 11-13 and nonpatent literature 3-5). In addition, if it uses a fluidized bed, the technique which uses a draft tube also in polyolefin manufacture is known (refer patent document 10).

Japanese Patent No. 2675919 US Pat. No. 5,235,009 JP 2002-537420 A Special Table 2002-520426 European Patent Application No. 1484343 JP-T-2006-502263 JP 59-42039 A JP-T-2002-515516 JP 58-216735 A International Publication No. 02/40547 Japanese Examined Patent Publication No. 6-76239 U.S. Pat. No. 4,373,272 Japanese Patent No. 3352059

G. Weikkert, Chemie Ingenieur Technik 2005, 77, no. 8, p. 977 Akira Yokokawa, Journal of Powder Engineering, 1997, vol. 21, no. 11, p. 715-p. 723 Yasuo Hirote et al., Journal of Powder Engineering, 1997, vol. 34, no. 5, p. 343-p. 360 Takenaka Sohei, Abstract of the 71st Annual Meeting of the Chemical Society of Japan J123, 2006 Toshifumi Ishikura et al., Chemical Engineering Papers, 1996, VOL. 22, no. 3, p. 615-p. 621

  However, in the method of Patent Document 1 in which a plurality of zones are formed in a horizontal direction in a container, it is necessary to provide a stirring paddle or the like in the container, which causes a problem that the structure is complicated and the energy required for stirring the particles is large. It was. Further, in the method of Patent Document 2 in which a large number of fluidized beds are connected in series in the vertical direction, it is necessary to provide a free board portion at each stage, so that the height of the apparatus may be huge. Further, in Patent Document 3 in which polymerization is carried out in one pass in a tubular reactor, it is necessary to lengthen the tube extremely in order to obtain a sufficient residence time.

  In addition, in the circulating fluidized bed type apparatuses as in Patent Documents 4 and 5, although the molecular weight distribution and copolymer composition distribution of each polyolefin particle are wide and uniform, the number of circulations in the apparatus can be controlled. The residence time distribution of polyolefin particles in the apparatus cannot be made substantially narrow. In the case of a fluidized bed using a dispersion plate, it is disadvantageous in terms of pressure loss. In addition, although the fluidized bed apparatus described in Patent Documents 6 to 8 does not necessarily require a gas dispersion plate, there is room for improvement in terms of volumetric efficiency.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide an olefin polymerization reaction apparatus having a narrow particle residence time distribution and a small pressure loss, and a polyolefin production system including the olefin polymerization reaction apparatus. Moreover, it aims at providing the polyolefin manufacturing method using the said olefin polymerization reaction apparatus or polyolefin manufacturing system.

  The olefin polymerization reaction apparatus according to the present invention includes a cylindrical portion extending in the vertical direction, a reduced diameter portion formed in the cylindrical portion, having a smaller inner diameter as it goes downward and having a gas introduction opening at the lower end, and a cylindrical portion. A spouted bed in a reaction region provided with a draft tube extending upward from a position spaced apart from the gas introduction opening and surrounded by the inner surface of the reduced diameter portion and the inner surface of the cylindrical portion above the reduced diameter portion Is formed.

  In the spouted bed type olefin polymerization reaction apparatus of the present invention, an olefin-containing gas is introduced upward from the gas introduction opening at the lower end of the reduced diameter portion into a reaction region in which a particle layer is formed by containing polyolefin particles containing a catalyst. It is made to flow at a high speed to form a spouted bed in the reaction zone. Here, the spouted bed is a particle layer composed of polyolefin particles (hereinafter sometimes simply referred to as “particles”) due to the action of the olefin-containing gas from the gas introduction opening, and has a particle concentration near the central axis of the cylindrical portion. While a thin jet is formed with the gas flowing upward with the gas (jet part), an annular structure is formed in which the particle descends in the form of a moving layer under the influence of gravity. The state of the particle layer.

  Part of the olefin-containing gas blown from the gas introduction opening forms a jet and blows through the particle layer and the draft tube, and the rest diffuses into the part of the particle layer having an annular structure. Thus, when the olefin-containing gas and the polyolefin particles come into solid-gas contact, the polyolefin particles grow by polymerization of the olefin in the reaction region. In the present invention, by installing a draft tube extending in the vertical direction at a predetermined position in the reaction region, it is possible to form a spouted bed that has sufficiently high stability and can reduce pressure loss.

  The draft tube has a straight pipe portion that extends downward from the upper end opening with a constant diameter, and an enlarged diameter portion that increases in diameter as it goes downward from the edge of the straight pipe portion, and the enlarged diameter portion extends from the gas introduction opening. It is preferable to extend to a separated position. By employing the draft tube having such a configuration, it is possible to increase the amount of gas flowing into the annular particle layer that contributes to the removal of the polymerization heat of the polyolefin particles. Thereby, polyolefin particles can be grown stably.

  In general, it is known that the spouted bed can exhibit superior performance in terms of pressure loss as compared with the fluidized bed, and that mixing slightly close to the plug flow occurs due to the circulating movement of particles. Therefore, the spouted bed type olefin polymerization reaction apparatus according to the present invention has an advantage that the residence time distribution of particles in the reaction region can be reduced as compared with a conventional apparatus using a fluidized bed. Also, when producing relatively large polyolefin particles with a particle size of several millimeters, which require an excessive gas flow rate for fluidization in the fluidized bed, the spouted bed has a lower gas flow rate than the fluidized bed. There is also an advantage that fluidization is possible.

  The olefin polymerization reaction apparatus of the present invention is disposed above the upper end opening of the draft tube in the reaction region, the outer diameter increases toward the lower side, the upper end is closed, and the lower end is separated from the inner wall of the cylindrical portion. Preferably, the first conical baffle is further provided.

  In a conventional fluidized bed type apparatus, it is necessary to secure a certain freeboard zone in order to suppress particle scattering. In the apparatus of the present invention, the first conical baffle disposed above the draft tube serves as a baffle that suppresses scattering of the jetted particles. Therefore, the freeboard zone can be shortened, and a high volumetric efficiency can be achieved as compared with a fluidized bed type apparatus.

  The olefin polymerization reaction apparatus of the present invention preferably has a plurality of the reaction regions, and the polyolefin particles sequentially pass through the reaction regions. Further, from the viewpoint of space saving of the apparatus, it is more preferable that the plurality of reaction regions are formed so as to be aligned in the vertical direction, and the polyolefin particles sequentially pass from the upper reaction region to the lower reaction region. By using an ejector or the like, the polyolefin particles can be passed from below to above. By providing a plurality of reaction regions and making the spouted bed multistage, the particle residence time distribution can be sufficiently reduced. Further, as described above, the spouted bed, unlike the conventional fluidized bed, is slightly mixed with the plug flow, so that the residence time distribution can be narrowed equally with a smaller number of stages than when the fluidized bed is multistaged.

  In the olefin polymerization reaction apparatus having a plurality of reaction zones provided in series as described above and having a multi-stage spouted bed, it is provided with a transfer means for transferring polyolefin particles from the upstream reaction zone to the downstream reaction zone. It is preferable.

  The olefin polymerization reaction apparatus of the present invention preferably further includes a tubular portion extending downward from the edge of the gas introduction opening of the reduced diameter portion. When gas is introduced from the tubular portion into the reaction region, such a tubular portion is not provided, and the gas flows upward in the reaction region as compared with the case where the gas is simply introduced from the gas introduction opening. Is sufficiently stabilized. As a result, the flow state of the spouted bed can be sufficiently maintained even if the flow rate of the introduced gas and the amount of particles in the reaction region vary somewhat. In addition, when the tubular portion is provided, even if the particles are likely to fall downward from the gas introduction opening due to gravity, the particles are pushed up by the gas flowing in from the lower side in the pipe and returned to the reaction region again. There is also an advantage that it is easy.

  It is preferable that the tubular portion further includes a partition that divides the inside of the pipe line in the horizontal direction. By adopting a tubular portion having a partition wall, the effect of pushing up particles that are likely to fall downward from the gas introduction opening is improved, and the falling particles can be further reduced.

  The olefin polymerization reaction apparatus according to the present invention further includes a cylindrical member having at least one end closed and disposed inside the tubular portion, and a pipe line leading to the gas introduction opening is formed between the outer surface of the cylindrical member and the tubular portion. It can also have an annulus formed by the inner surface. By adopting such a configuration, the horizontal cross section of the pipe can be made into a ring shape, and compared with the case where a pipe having the same cross sectional area and a circular cross section is adopted as follows. There are significant advantages. First, as compared with a circular pipe, the effect of pushing up particles that are likely to drop downward from the gas introduction opening is improved, and the falling particles can be further reduced. The above configuration is effective when the reactor is scaled up. In other words, even when the gas introduction opening is enlarged, the cross section of the flow path up to this is a ring shape, so that the opening interval can be narrowed compared to the case where the cross section is circular. It is easy to form a stable spouted bed.

  The olefin polymerization reaction apparatus of the present invention comprises a closing plate for closing the lower end of the tubular portion, a gas introduction pipe provided so as to penetrate the closing plate, having a pipe line narrower than the pipe line of the tubular part, and below A second conical baffle having an outer diameter that increases toward the end and is closed at the upper end and is spaced from the inner surface of the tubular portion, and the second conical baffle is disposed immediately above the upper end of the gas introduction pipe. It may be provided. According to the reactor of the above configuration, since the second conical baffle serves as a particle fall prevention plate, it is sufficient for the particles to fall through the gas introduction opening even when the gas supply is stopped. Can be prevented.

  The olefin polymerization reaction apparatus of the present invention preferably communicates with the inside of the draft tube, and further includes a pipe for supplying gas or liquid into the draft tube. By supplying gas or liquid into the draft tube through this pipe, the gas composition in the draft tube can be made different from the gas composition outside the draft tube. Thereby, it is possible to produce polyolefin particles having a wide molecular weight distribution and copolymer composition distribution and uniform.

  The polyolefin production method according to the present invention is to polymerize olefins by using the above-mentioned olefin polymerization reaction apparatus to form a spouted layer of polyolefin particles in the reaction region. The polyolefin production method according to the present invention continuously supplies olefin to an olefin polymerization reactor, continuously withdraws gas containing unreacted olefin from the olefin polymerization reactor, and supplies the extracted gas to the olefin polymerization reactor. It may be provided with a step of returning and a step of cooling all or part of the extracted gas to obtain a condensate containing olefin. In this case, it is preferable to supply the condensate to the jet part of the spouted bed formed in the reaction region of the olefin polymerization reactor. As a result, the latent heat of vaporization of the condensate can be used, and the heat removal from the olefin polymerization reaction apparatus of the condensate can be efficiently performed. Further, when the olefin polymerization reaction apparatus includes the first conical baffle, the condensate may be supplied to the lower part of the first conical baffle. In this case, there is an advantage that a line for supplying condensate can be disposed by using the jig of the first conical baffle.

  The polyolefin production system of the present invention includes an olefin prepolymerization reactor for polymerizing olefins in the presence of an olefin polymerization catalyst to form polyolefin particles, and the olefin polymerization reactor described above connected to a subsequent stage of the olefin prepolymerization reactor. With. The polyolefin production method of the present invention performs multistage polymerization of olefins using the above-described polyolefin production system.

  According to the present invention, it is possible to form a spouted bed that has sufficiently high stability and can also reduce pressure loss, and to reduce the particle residence time distribution. Accordingly, when the olefin polymer is continuously produced, it is possible to produce a polymer having excellent uniformity on the polymer structure, and it is easy to replace the polymer in the reaction apparatus in accordance with the production condition change.

1 is a schematic configuration diagram showing an embodiment of a polyolefin production system according to the present invention. It is an expansion schematic sectional drawing of 10 A of olefin polymerization reaction apparatuses of FIG. It is a schematic block diagram which shows other embodiment of the polyolefin manufacturing system which concerns on this invention. It is a schematic block diagram which shows other embodiment of the polyolefin manufacturing system which concerns on this invention. It is a schematic block diagram which shows other embodiment of the polyolefin manufacturing system which concerns on this invention. (A) And (b) is sectional drawing which shows the structure of a draft tube. It is sectional drawing which shows the tubular part extended below from the edge of the opening for gas introduction. (A)-(c) is a figure which shows the structure of a gas introduction part. (A) And (b) is a figure which shows the structure of a gas introduction part. (A) And (b) is a figure which shows the structure of a gas introduction part. It is a schematic cross section which shows the tubular part by which the cylindrical member was arrange | positioned. It is a schematic cross section which shows the tubular part by which the gas introduction pipe and the 2nd conical baffle were arrange | positioned. It is a schematic cross section which shows the gas introduction pipe and 2nd conical baffle arrange | positioned at the tubular part. It is a schematic cross section which shows the extension pipe | tube which has a bellmouth-shaped lower end part.

  Hereinafter, preferred embodiments of the present invention will be described in detail. Further, the positional relationship such as up, down, left and right is based on the positional relationship shown in the drawings unless otherwise specified. Further, the dimensional ratios in the drawings are not limited to the illustrated ratios.

(Polyolefin production system)
FIG. 1 shows a polyolefin production system 100A according to this embodiment. This manufacturing system 100 </ b> A includes an olefin prepolymerization reaction apparatus 5 and an olefin polymerization reaction apparatus 10 </ b> A connected to a subsequent stage of the olefin prepolymerization reaction apparatus 5.

(Olefin prepolymerization reactor)
The olefin prepolymerization reactor 5 polymerizes olefins in the presence of an olefin polymerization catalyst to form polyolefin particles.

  Although it does not specifically limit as the olefin prepolymerization reaction apparatus 5, For example, a slurry polymerization reaction apparatus, a block polymerization reaction apparatus, a stirring tank type gas phase polymerization reaction apparatus, and a fluid bed type gas phase polymerization reaction apparatus are mentioned. In addition, these apparatuses may be used individually by 1 type, may be used combining several apparatus of the same kind, and may be used combining two or more different kinds of apparatuses.

  Examples of the slurry polymerization reaction apparatus include known polymerization reaction apparatuses such as a stirring tank type reaction apparatus and a loop type reaction apparatus described in Japanese Patent Publication No. 41-12916, Japanese Patent Publication No. 46-11670, and Japanese Patent Publication No. 47-42379. A device or the like can be used. In addition, slurry polymerization is performed using an aliphatic solvent such as propane, butane, isobutane, pentane, hexane, heptane, and octane; an inert solvent such as cycloaliphatic hydrocarbon such as cyclopentane and cyclohexane, and an olefin such as propylene and butene. This is a method in which a monomer added is used as a polymerization solvent, an olefin polymerization catalyst is dispersed in a slurry in the polymerization solvent, and the polymerization is carried out in a state where the resulting polymer is not dissolved in the polymerization solvent. The polymerization is carried out at a temperature and pressure at which the polymerization solvent is kept in a liquid state and the produced polymer is not dissolved in the polymerization solvent. The polymerization temperature is usually from 30 to 100 ° C, preferably from 50 to 80 ° C. The polymerization pressure is usually normal pressure to 10 MPaG, preferably 0.3 to 5 MPaG.

  Examples of the bulk polymerization reaction apparatus include known polymerization reaction apparatuses, for example, a stirring tank type reaction apparatus and a loop type reaction described in Japanese Patent Publication Nos. 41-12916, 46-11670, 47-42379. A device or the like can be used. In addition, bulk polymerization is substantially free of inert solvents such as aliphatic hydrocarbons such as propane, butane, isobutane, pentane, hexane, heptane, and octane; alicyclic hydrocarbons such as cyclopentane and cyclohexane, This is a method in which an olefin monomer such as propylene or butene is used as a polymerization solvent, an olefin polymerization catalyst is dispersed in the polymerization solvent, and the polymerization is performed in a state where the resulting polymer is not dissolved in the polymerization solvent. The polymerization is carried out at a temperature and pressure at which the polymerization solvent is kept in a liquid state and the produced polymer is not dissolved in the polymerization solvent. The polymerization temperature is usually from 30 to 100 ° C, preferably from 50 to 80 ° C. The polymerization pressure is usually normal pressure to 10 MPaG, preferably 0.5 to 5 MPaG.

  As the stirred tank type gas phase polymerization reaction apparatus, a known polymerization reaction apparatus, for example, a reaction apparatus described in JP-B-46-31969 and JP-B-59-21321 can be used. The stirred tank type gas phase polymerization uses a gaseous monomer as a medium and polymerizes the gaseous monomer in the medium while keeping the olefin polymerization catalyst and the olefin polymer in a fluid state by a stirrer. Is the method. The polymerization temperature is usually from 50 to 110 ° C, preferably from 60 to 100 ° C. The polymerization pressure may be within a range in which olefin can exist as a gas phase in the stirred tank gas phase polymerization reactor, and is usually normal pressure to 5 MPaG, preferably 0.5 to 3 MPaG.

  As the fluidized bed gas phase polymerization reaction apparatus, a known reaction apparatus, for example, a reaction apparatus described in JP-A-58-201802, JP-A-59-126406, or JP-A-2-233708 is used. be able to. The fluidized bed gas phase polymerization uses a gaseous monomer as a medium, and the olefin polymerization catalyst and the olefin polymer are maintained in a fluid state mainly by the flow of the medium in the medium while the gaseous monomer is used. This is a method of polymerizing. In order to promote fluidization, a stirrer may be additionally provided. The polymerization temperature is usually 0 to 120 ° C, more preferably 20 to 100 ° C, and further preferably 40 to 100 ° C. The polymerization pressure may be within a range in which olefin can exist as a gas phase in the fluidized bed reactor, and is usually normal pressure to 10 MPaG, more preferably 0.2 to 8 MPaG, still more preferably 0.5 to 5 MPaG. It is.

  As a combination of each reaction apparatus, the aspect which connected the fluidized bed type gas phase polymerization reaction apparatus or the stirring tank type gas phase polymerization reaction apparatus to the back | latter stage of a slurry polymerization reaction apparatus or a block polymerization reaction apparatus is mention | raise | lifted, for example.

  Also, a slurry polymerization reactor or a bulk polymerization reactor, and a subsequent stage, for example, a fluidized bed gas phase polymerization reactor, a stirred tank gas phase polymerization reactor, or an olefin polymerization reactor 10A described later, etc. In general, a flushing tank for separating unreacted olefin or polymerization solvent and olefin polymer particles is provided between the gas phase polymerization reaction apparatus. However, the flushing tank is not necessarily required. In particular, when a bulk polymerization reactor is used, there are many cases where the flushing tank is not installed.

(Olefin polymerization reactor)
The olefin polymerization reaction apparatus 10 </ b> A is an apparatus that causes the polyolefin particles generated by the olefin prepolymerization reaction apparatus 5 to perform an olefin polymerization reaction substantially in a gas phase state.

  As shown in FIG. 1, the olefin polymerization reaction apparatus 10 </ b> A mainly includes a cylinder 12 extending in the vertical direction, a plurality of baffle plates (first conical baffles) 20 provided in the cylinder 12, and a plurality of provided in the cylinder 12. A cylindrical baffle (reduced diameter portion) 30 is provided. The baffle plates 20 and the cylindrical baffles 30 are alternately arranged in the axial direction of the cylinder. The baffle plate 20 and the cylindrical baffle 30 are preferably arranged coaxially with the axis of the cylinder 12. From the viewpoint of stabilizing the spouted bed, the inner diameter of the cylinder 12 is preferably 5 m or less, and more preferably 3.5 m or less.

  In the olefin polymerization reaction apparatus 10 </ b> A, five stages of reaction regions 25 are formed in the cylinder 12 so as to be aligned in the vertical direction. The reaction region 25 is a region surrounded by the outer surface of the cylindrical baffle 30, the inner surface of the cylindrical baffle 30 immediately below, and the inner surface of the portion of the cylinder 12 (cylindrical portion) between the cylindrical baffles 30. is there. However, the uppermost reaction region 25 is a region surrounded by the inner surface of the top portion of the cylinder 12, the inner surface of the cylindrical baffle 30 immediately below, and the inner surface of the portion of the cylinder 12 (cylindrical portion) therebetween. It is.

  In each reaction region 25, the olefin-containing gas flows at high speed from the gas introduction opening formed at the lower end 30b of the cylindrical baffle 30 so that a spouted layer of polyolefin particles is formed. It has become.

  A draft tube T <b> 1 is installed in each reaction region 25 coaxially with the axis of the cylinder 12. By using the draft tube T1, the stability of the spouted bed can be improved. The draft tube T1 is a straight pipe extending upward from a position separated from the gas introduction opening of the cylindrical baffle 30.

  The ratio (Lc / Do) between the distance (clearance) Lc between the lower end T1a of the draft tube T1 and the gas introduction opening of the cylindrical baffle 30 and the diameter Do of the gas introduction opening of the cylindrical baffle 30 is 0.5. It is preferable that it is -5, and it is more preferable that it is 0.7-4. When the ratio Lc / Do is less than 0.5, gas diffusion to the annular portion of the spouted layer tends to be insufficient, and when it exceeds 5, the stability of the spouted layer tends to be insufficient. .

The draft tube T1 can have a length such that the upper end T1b protrudes from the powder surface of the spouted bed. Thereby, the pressure loss in the spouted bed is further reduced. On the other hand, the draft tube T1 may have a length at which the upper end T1b is lower than the powder surface of the spouted bed. Thereby, gas diffusibility can be improved to an annular particle layer. Ratio to the inner diameter _{D R} of the cylinder 12 of the length Lt of the draft tube (Lt / _{D R),} from the viewpoint of stability and gas diffusibility of the spouted bed, preferably 0.5 or more, 0.8 or more It is more preferable that

  The ratio (Dt / Do) of the inner diameter Dt of the draft tube T1 to the diameter Do of the gas introduction opening is preferably 0.8 or more, from the viewpoint of the stability of the spouted bed and the gas diffusibility, 1.0 or more. It is more preferable that

  As shown in FIG. 2, baffle plates 20 are disposed above the cylindrical baffle 30 in each reaction region 25 and at positions facing the gas introduction openings. The baffle plate 20 plays a role in preventing the jetted polyolefin particles from scattering. Thereby, the freeboard zone can be shortened and high volumetric efficiency is achieved.

  The baffle plate 20 has a conical shape in which the outer diameter increases toward the lower side while the upper end 20 a is closed, and the lower end 20 b is separated from the inner wall of the cylinder 12. Thereby, the blown-up particles collide with the inner surface of the baffle plate 20 and are taken into the annular structure of the spouted bed. On the other hand, the gas flows upward between the lower end 20 b and the inner wall of the cylinder 12.

  The cylindrical baffle 30 is a tapered cylinder whose inner diameter becomes smaller toward the lower side, and the upper end 30 a is in contact with the inner wall of the cylinder 12. As a result, the gas flows upward from the circular gas introduction opening at the lower end 30 b and does not flow between the upper end 30 a and the cylinder 12. Note that the gas introduction opening formed in the lower end 30b has a check so that the polyolefin particles in the reaction region 25 do not flow downward from the gas introduction opening when the olefin polymerization reactor 10A is started or temporarily stopped. A valve (not shown) may be provided.

  As shown in FIG. 1, the upper four cylindrical baffles 30 provided in the cylinder 12 are provided with downcomer pipes 35a so as to penetrate the upper four cylindrical baffles 30, and the lowermost cylindrical baffle 30 has a downcomer pipe. 35b is provided. The downcomer tube 35 a lowers the polyolefin particles from the upper reaction region 25 to the lower reaction region 25. The downcomer tube 35 b is for extracting polyolefin particles from the lowermost reaction region and discharging them out of the cylinder 12. Two valves V71 and V72 are arranged in series on the downcomer pipe 35b. By sequentially opening and closing these valves, the polyolefin particles can be discharged to the next step.

In order to form a stable spouted bed in each reaction region 25, the cylindrical baffle 30 preferably satisfies the following conditions. That is, the tubular baffle 30, that ratio to the inner diameter _{D R} of the cylinder 12 of the opening diameter _{D O} of the gas inlet opening of the lower end 30b of the tubular baffle 30 _(D O / _{D R)} is 0.35 or less preferable. In addition, the inclination angle α30 of the cylindrical baffle 30 in FIG. 2, that is, the angle formed with the horizontal plane of the inner surface of the cylindrical baffle 30, is preferably equal to or greater than the repose angle of the polyolefin particles present in the cylinder 12. α30 is more preferably the angle of repose or more, and more than the angle at which all polyolefin particles can be discharged naturally by gravity. Thereby, the smooth downward movement of the polyolefin particles is achieved.

  Although a spouted layer can be formed even when a flat plate in which an opening for gas introduction is employed instead of the cylindrical baffle 30, a region where particles are not fluidized in the vicinity of the inner surface of the cylinder 12 on the flat plate. Occurs. If it does so, there exists a possibility that particle | grains may melt and agglomerate by heat removal defect in this area | region. Therefore, in order to avoid such a situation, it is preferable that the inclination angle α30 of the cylindrical baffle 30 is not less than a predetermined angle as described above.

  The inclination angle α20 of the baffle plate 20 in FIG. 2, that is, the angle formed with the horizontal surface of the outer surface of the baffle plate 20 is preferably set to be equal to or greater than the repose angle of the polyolefin particles present in the cylinder 12. Thereby, it is possible to sufficiently prevent the polyolefin particles from adhering to the baffle plate 20.

  The repose angle of the polyolefin particles is, for example, about 35 to 50 °, and the inclination angles α30 and α20 are preferably set to 55 ° or more.

  The baffle plate 20 and the cylindrical baffle 30 are each fixed to the cylinder 12 by a support (not shown), and there is almost no influence on the gas flow or polyolefin flow by the support. As a material of the cylinder 12, the baffle plate 20, and the cylindrical baffle 30, for example, carbon steel, SUS304, SUS316L, or the like can be used. Note that SUS is a stainless steel standard defined by JIS (Japanese Industrial Standard). When using a catalyst containing a large amount of corrosive components (for example, halogen components such as chlorine), it is preferable to use SUS316L.

  As shown in FIG. 1, a gas supply nozzle 38 is provided at the lower part of the cylinder 12, and the olefin monomer is supplied to the lower part of the cylinder 12 via a line L <b> 30. On the other hand, a gas discharge nozzle 61 is provided in the upper part of the cylinder 12. The gas rising in the cylinder 12 is discharged to the outside through the line L40, and gas entrained particles are discharged by the cyclone 62 installed as necessary. The gas is processed in the heat exchanger 63, the compressor 64, the heat exchanger 65, and the gas-liquid separator 66, and then introduced into the line L30 via the line L35 and recycled. In addition to the gas supply nozzle 38, a discharge nozzle (not shown) that can discharge the polyolefin particles at the end of the operation may be provided at the lower part of the cylinder 12. Further, for the purpose of reducing the residual amount of powder in the olefin polymerization reaction apparatus 10A at the end of the operation, an inverted cone-shaped interior (not shown) is provided at a position where the gas flow in the lower part of the cylinder 12 is not hindered. May be installed.

  The cylinder 12 is provided with a liquid supply nozzle 50 for supplying the liquid olefin separated by the gas-liquid separator 66 from the outside of the cylinder 12 into the predetermined reaction region 25. More specifically, as shown in FIG. 1, the liquid supply nozzle 50 is disposed in the vicinity of the gas introduction opening of the second-stage cylindrical baffle 30 so that liquid olefin is injected toward the jet. It has become. The liquid supply nozzle 50 is connected to a pump 52 and a line L20 for supplying the liquefied olefin monomer as needed. In FIG. 1, the liquid supply nozzle 50 is disposed in the vicinity of the gas introduction opening of the cylindrical baffle 30, but the position of the liquid supply nozzle 50 is not limited to this, and for example, a deflection is provided. It may be arranged near the lower end of the plate 20. In addition, it is preferable that the liquid supply nozzle 50 is installed in the area | region used as a high gas flow rate like the jet part in which a jet is formed.

  Further, a plurality of gas discharge nozzles 60 are provided in a portion of the cylinder 12 facing the outer surface of the cylindrical baffle 30. More specifically, as shown in FIG. 1, the gas discharge nozzle 60 is provided at a portion facing the outer surface of the second-stage cylindrical baffle 30 from the top. The gas discharge nozzle 60 is connected to the line L40 via the line L41. The amount of gas discharged from the gas discharge nozzle 60 is controlled by a valve or the like so as to be substantially the same as the amount of gas supplied from the liquid supply nozzle 50 and vaporized. Therefore, even when the olefin monomer liquefied from the liquid supply nozzle 50 is supplied into the cylinder 12, the gas cylinder speed in the cylinder 12 is maintained substantially constant up and down.

  A line L5 is connected to a position higher than the uppermost cylindrical baffle 30 in the cylinder 12, and polyolefin particles containing olefin polymerization catalyst solid particles are supplied to the uppermost reaction region 25.

  In this way, in the present embodiment, a two-stage polymerization process is realized by the olefin prepolymerization reaction apparatus 5 and the olefin polymerization reaction apparatus 10A. In this way, by polymerizing and growing the polyolefin particles by the olefin prepolymerization reactor 5, it is preferable to obtain relatively large polyolefin particles having a particle diameter of preferably 500 μm or more, more preferably 700 μm or more, and particularly preferably 850 μm or more. A more stable spouted layer can be formed. However, a single-stage polymerization process without the olefin prepolymerization reactor 5 can also be used. In this case, the olefin polymerization catalyst or the prepolymerization catalyst is directly supplied to the olefin polymerization reaction apparatus 10A, and the olefin is polymerized. Further, one or a plurality of additional olefin polymerization reaction devices such as the olefin prepolymerization reaction device 5 and the olefin polymerization reaction device 10A are provided at the subsequent stage of the olefin polymerization reaction device 10A to realize a polymerization process of three or more stages. Also good.

(Olefin, polyolefin, catalyst, etc.)
Next, olefins, polyolefins, catalysts, etc. in such a system will be described in detail.

  In the olefin polymerization reaction apparatus, polyolefin production method and polyolefin production system of the present invention, olefin is polymerized (homopolymerization, copolymerization) to produce a polyolefin, that is, an olefin polymer (olefin homopolymer, olefin copolymer). . Examples of the olefin used in the present invention include ethylene, propylene, 1-butene, 1-pentene, 4-methyl-1-pentene, 5-methyl-1-hexene, 1-hexene, 1-heptene and 1-octene. can give.

  One or more of these olefins are used, and the olefin to be used may be changed in each polymerization step. When the olefin is used in a multistage polymerization method, the olefin to be used may be different from each other in each step. As a combination of olefins when two or more olefins are used, propylene / ethylene, propylene / 1-butene, propylene / ethylene / 1-butene, ethylene / 1-butene, ethylene / 1-hexene, ethylene / 1-octene, etc. Can be given. In addition to olefins, other copolymer components such as dienes may be used in combination.

  In the present invention, for example, olefin polymers such as propylene homopolymer, propylene / ethylene copolymer, propylene / 1-butene copolymer, propylene / ethylene / 1-butene copolymer (homopolymer, copolymer) ) Can be suitably produced. In particular, it is suitable for the production of an olefin polymer obtained by multistage polymerization in which the content ratio of monomer units constituting the polymer component is different. For example, in the olefin prepolymerization reaction apparatus 5 and the olefin polymerization reaction apparatus 10A By supplying one type of olefin, homopolymer particles or random copolymer particles copolymerized with a small amount of another type of olefin are formed, and the olefin prepolymerization reactor 5 and the olefin polymerization reactor 10A are used in the subsequent stage. In such an additional olefin polymerization reactor, two or more olefins can be supplied to the polymer particles to produce a multistage polymerized olefin copolymer. In this case, since the residence time distribution in the olefin polymerization reaction apparatus 10A is narrow, the composition ratio in the polymer particles is easily made constant, which is particularly effective in reducing defects during molding.

  Examples of the polymer include propylene-propylene / ethylene polymer, propylene / propylene / ethylene / propylene / ethylene polymer, propylene / ethylene / propylene / ethylene polymer, and propylene / propylene / ethylene / 1-butene polymer. Can give. Here, “-” indicates a boundary between the polymers, and “•” indicates that two or more olefins are copolymerized in the polymer. Among these, a polymer having a monomer unit based on propylene, referred to as high-impact polypropylene (also commonly referred to as a polypropylene block copolymer in Japan), a crystalline propylene polymer part and an amorphous propylene polymer. Is suitable for the production of a multistage polymerized propylene copolymer. The multistage polymerized propylene copolymer is composed of a crystalline homopolypropylene part or a random copolymer part copolymerized with a small amount of an olefin other than propylene, amorphous ethylene and propylene, ethylene as an optional component, and an olefin other than propylene. In the presence of the respective polymers, and obtained by polymerizing in multiple stages continuously in an arbitrary order, in 1,2,3,4-tetrahydronaphthalene at 135 ° C. The intrinsic viscosity measured by is preferably in the range of 0.1 to 100 dl / g. Since this multistage polymerized propylene copolymer is excellent in heat resistance, rigidity and impact resistance, it can be used in various packaging containers such as automobile parts such as bumpers and door trims and retort food packaging containers.

  Moreover, in the olefin polymerization reaction apparatus and the production method of the present invention, the molecular weight of the olefin polymer component produced in each polymerization step may be different in order to broaden the molecular weight distribution of the olefin polymer. The present invention is also suitable for the production of a wide molecular weight distribution olefin polymer, for example, the intrinsic viscosity obtained by the above measurement of the polymer component produced in the polymerization step of producing the polymer component having the highest molecular weight, Preferably it is in the range of 0.5 to 100 dl / g, more preferably in the range of 1 to 50 dl / g, particularly preferably 2 to 20 dl / g, and the intrinsic viscosity produces a polymer component having the lowest molecular weight. The amount of the polymer component produced in the polymerization step for producing the polymer component having the highest molecular weight which is 5 times or more the intrinsic viscosity of the polymer component produced in the polymerization step is 0.1% in the olefin polymer. An olefin polymer containing -80% by weight can be suitably produced.

  As the olefin polymerization catalyst used in the present invention, a known addition polymerization catalyst used for olefin polymerization can be used. As a specific example, a Ziegler system comprising a solid catalyst component containing titanium, magnesium, halogen and an electron donor (hereinafter referred to as catalyst component (A)), an organoaluminum compound component and an electron donor component. Examples thereof include solid catalysts, metallocene solid catalysts in which a metallocene compound and a promoter component are supported on a particulate carrier. Moreover, these catalysts can also be used in combination.

  As the catalyst component (A) used for the preparation of the Ziegler-based solid catalyst, what is generally called a titanium / magnesium composite catalyst can be used. The following titanium compound, magnesium compound, and electron It can be obtained by contacting the donor.

As a titanium compound used for the preparation of the catalyst component (A), for example, the general formula Ti (OR ¹ ) _a X _4-a (R ¹ is a hydrocarbon group having 1 to 20 carbon atoms, and X is a halogen atom. , A represents a number of 0 ≦ a ≦ 4)). Specifically, tetrahalogenated titanium compounds such as titanium tetrachloride; trihalogenated alkoxytitanium compounds such as ethoxytitanium trichloride and butoxytitanium trichloride; dihalogenated dialkoxytitanium such as diethoxytitanium dichloride and dibutoxytitanium dichloride Compounds; monohalogenated trialkoxytitanium compounds such as triethoxytitanium chloride and tributoxytitanium chloride; and tetraalkoxytitanium compounds such as tetraethoxytitanium and tetrabutoxytitanium. These titanium compounds may be used alone or in combination of two or more.

  Examples of the magnesium compound used for the preparation of the catalyst component (A) include a magnesium compound having a magnesium-carbon bond or a magnesium-hydrogen bond and having a reducing ability, or a magnesium compound having no reducing ability. . Specific examples of magnesium compounds having reducing ability include dialkyl magnesium compounds such as dimethyl magnesium, diethyl magnesium, dibutyl magnesium, and butyl ethyl magnesium; alkyl magnesium halide compounds such as butyl magnesium chloride; alkyl alkoxy magnesium compounds such as butyl ethoxy magnesium; Examples thereof include alkyl magnesium hydrides such as butyl magnesium hydride. These magnesium compounds having a reducing ability may be used in the form of a complex compound with an organoaluminum compound.

  On the other hand, specific examples of magnesium compounds having no reducing ability include magnesium halide compounds such as magnesium dichloride; alkoxymagnesium halide compounds such as methoxymagnesium chloride, ethoxymagnesium chloride and butoxymagnesium chloride; diethoxymagnesium and dibutoxymagnesium. Dialkoxymagnesium compounds such as magnesium; carboxylates of magnesium such as magnesium laurate and magnesium stearate; These magnesium compounds not having a reducing ability may be synthesized in advance by a known method from a magnesium compound having a reducing ability at the time of preparing the catalyst component (A).

  The electron donor used for the preparation of the catalyst component (A) includes alcohols, phenols, ketones, aldehydes, carboxylic acids, esters of organic acids or inorganic acids, ethers, acid amides, acid anhydrides. Oxygen-containing electron donors such as ammonia; nitrogen-containing electron donors such as ammonia, amines, nitriles and isocyanates; and organic acid halides. Of these electron donors, inorganic acid esters, organic acid esters and ethers are preferably used.

The inorganic acid ester is preferably a general formula R ² _n Si (OR ³ ) _4-n (R ² represents a hydrocarbon group having 1 to 20 carbon atoms or a hydrogen atom, and R ³ has 1 to 20 carbon atoms. And a silicon compound represented by the following formula: n represents a number of 0 ≦ n <4. Specifically, tetraalkoxysilanes such as tetramethoxysilane, tetraethoxysilane, and tetrabutoxysilane; methyltrimethoxysilane, ethyltrimethoxysilane, butyltrimethoxysilane, isobutyltrimethoxysilane, t-butyltrimethoxysilane, methyl Alkyltrialkoxysilanes such as triethoxysilane, ethyltriethoxysilane, butyltriethoxysilane, isobutyltriethoxysilane, t-butyltriethoxysilane; dimethyldimethoxysilane, diethyldimethoxysilane, dibutyldimethoxysilane, diisobutyldimethoxysilane, di- t-butyldimethoxysilane, butylmethyldimethoxysilane, butylethyldimethoxysilane, t-butylmethyldimethoxysilane, dimethyldiethoxysilane Dialkyldialkoxy such as diethyldiethoxysilane, dibutyldiethoxysilane, diisobutyldiethoxysilane, di-t-butyldiethoxysilane, butylmethyldiethoxysilane, butylethyldiethoxysilane, t-butylmethyldiethoxysilane Examples thereof include silane.

  As the organic acid esters, mono- and polyvalent carboxylic acid esters are preferably used, and examples thereof include aliphatic carboxylic acid esters, alicyclic carboxylic acid esters, and aromatic carboxylic acid esters. Specific examples include methyl acetate, ethyl acetate, methyl propionate, ethyl propionate, ethyl butyrate, ethyl valerate, methyl acrylate, ethyl acrylate, methyl methacrylate, ethyl benzoate, butyl benzoate, methyl toluate, Ethyl toluate, ethyl anisate, diethyl succinate, dibutyl succinate, diethyl malonate, dibutyl malonate, dimethyl maleate, dibutyl maleate, diethyl itaconate, dibutyl itaconate, diethyl phthalate, di-n-phthalate Examples thereof include butyl and diisobutyl phthalate. Preferred are unsaturated aliphatic carboxylic acid esters such as methacrylic acid esters, maleic acid esters and phthalic acid esters, and more preferred are phthalic acid diesters.

  Examples of ethers include dialkyl ethers such as diethyl ether, dibutyl ether, diisobutyl ether, diamyl ether, diisoamyl ether, methyl butyl ether, methyl isoamyl ether, and ethyl isobutyl ether. Dibutyl ether and diisoamyl ether are preferred.

  Examples of the organic acid halides include mono- and polyvalent carboxylic acid halides, and examples thereof include aliphatic carboxylic acid halides, alicyclic carboxylic acid halides, and aromatic carboxylic acid halides. Specific examples include acetyl chloride, propionic acid chloride, butyric acid chloride, valeric acid chloride, acrylic acid chloride, methacrylic acid chloride, benzoyl chloride, toluic acid chloride, anisic acid chloride, succinic acid chloride, malonic acid chloride, maleic acid chloride, Examples thereof include itaconic acid chloride and phthalic acid chloride. Aromatic carboxylic acid chlorides such as benzoyl chloride, toluic acid chloride, and phthalic acid chloride are preferable, and phthalic acid chloride is more preferable.

Examples of the method for preparing the catalyst component (A) include the following methods.
(1) A method in which a liquid magnesium compound or a complex compound comprising a magnesium compound and an electron donor is reacted with a precipitating agent and then treated with a titanium compound, or a titanium compound and an electron donor.
(2) A method of treating a solid magnesium compound or a complex compound comprising a solid magnesium compound and an electron donor with a titanium compound, or a titanium compound and an electron donor.
(3) A method in which a liquid magnesium compound and a liquid titanium compound are reacted in the presence of an electron donor to precipitate a solid titanium composite.
(4) A method in which the reaction product obtained in (1), (2) or (3) is further treated with a titanium compound, or an electron donor and a titanium compound.
(5) A method of treating a solid product obtained by reducing an alkoxytitanium compound with an organomagnesium compound such as a Grignard reagent in the presence of an organosilicon compound having a Si—O bond with an ester compound, an ether compound and titanium tetrachloride. .
(6) A solid product obtained by reducing a titanium compound with an organomagnesium compound in the presence of an organosilicon compound or an organosilicon compound and an ester compound is converted into a mixture of an ether compound and titanium tetrachloride, and then an organic acid halide compound. And then treating the treated solid with a mixture of an ether compound and titanium tetrachloride or a mixture of an ether compound, titanium tetrachloride and an ester compound.
(7) A method in which a contact reaction product of a metal oxide, dihydrocarbylmagnesium and a halogen-containing alcohol is contacted with an electron donor and a titanium compound after or without treatment with a halogenating agent.
(8) A method in which a magnesium compound such as a magnesium salt of an organic acid or alkoxymagnesium is contacted with an electron donor and a titanium compound after or without treatment with a halogenating agent.
(9) A method of treating the compound obtained in (1) to (8) with any one of a halogen, a halogen compound and an aromatic hydrocarbon.

  Of these methods for preparing the catalyst component (A), the methods (1) to (6) are preferred. All of these preparations are usually performed under an inert gas atmosphere such as nitrogen or argon.

  In the preparation of the catalyst component (A), the titanium compound, the organosilicon compound and the ester compound are preferably used after being dissolved or diluted in a suitable solvent. Examples of the solvent include aliphatic hydrocarbons such as hexane, heptane, octane, and decane; aromatic hydrocarbons such as toluene and xylene; alicyclic hydrocarbons such as cyclohexane, methylcyclohexane, and decalin; diethyl ether, And ether compounds such as dibutyl ether, diisoamyl ether, and tetrahydrofuran.

  In the preparation of the catalyst component (A), the temperature of the reduction reaction using the organomagnesium compound is usually −50 to 70 ° C., and preferably from −30 to 50 ° C., particularly preferably from the viewpoint of increasing the catalyst activity and cost. -25 to 35 ° C. The dropping time of the organomagnesium compound is not particularly limited, but is usually about 30 minutes to 12 hours. Further, after the reduction reaction, a post-reaction may be performed at a temperature of 20 to 120 ° C.

In the preparation of the catalyst component (A), a porous material such as an inorganic oxide or an organic polymer may coexist in the reduction reaction, and the porous product may be impregnated with the porous product. As such a porous substance, those having a pore volume at a pore radius of 20 to 200 nm of 0.3 ml / g or more and an average particle diameter of 5 to 300 μm are preferable. Examples of the porous inorganic oxide include SiO ₂ , Al ₂ O ₃ , MgO, TiO ₂ , ZrO ₂ , and composite oxides thereof. In addition, examples of the porous polymer include polystyrene-based porous polymers such as polystyrene and styrene-divinylbenzene copolymer; polyethyl acrylate, methyl acrylate-divinylbenzene copolymer, polymethyl methacrylate, methyl methacrylate-divinyl. Examples thereof include polyacrylic ester porous polymers such as benzene copolymers; polyolefin porous polymers such as polyethylene, ethylene-methyl acrylate copolymers, and polypropylene. Among these porous materials, preferably _SiO 2, _Al 2 _{O 3,} a styrene - divinylbenzene copolymer.

The organoaluminum compound component used for the preparation of the catalyst of the Ziegler-based solid catalyst has at least one Al-carbon bond in the molecule, and a typical one is shown below by a general formula.
R ⁴ _m AlY _3-m
R ⁵ R ⁶ Al—O—AlR ⁷ R ⁸
(R ^{4 to} R ⁸ represent a hydrocarbon group having 1 to 8 carbon atoms, Y represents a halogen atom, hydrogen or an alkoxy group. R ^{4 to} R ⁸ may be the same or different. M is a number represented by 2 ≦ m ≦ 3.)

  Specific examples of the organoaluminum compound component include trialkylaluminum such as triethylaluminum and triisobutylaluminum; dialkylaluminum hydride such as diethylaluminum hydride and diisobutylaluminum hydride; dialkylaluminum halide such as diethylaluminum chloride and diisobutylaluminum chloride; triethylaluminum And a mixture of a trialkylaluminum and a dialkylaluminum halide such as a mixture of sodium and diethylaluminum chloride; an alkylalumoxane such as tetraethyldialumoxane and tetrabutyldialumoxane. Among these organoaluminum compounds, preferably trialkylaluminum, a mixture of trialkylaluminum and dialkylaluminum halide, alkylalumoxane, more preferably triethylaluminum, triisobutylaluminum, a mixture of triethylaluminum and diethylaluminum chloride, or Tetraethyl dialumoxane is preferred.

  The electron donor component used for the preparation of the Ziegler-based solid catalyst includes alcohols, phenols, ketones, aldehydes, carboxylic acids, esters of organic acids or inorganic acids, ethers, acid amides, acid anhydrides Commonly used ones such as oxygen-containing electron donors such as ammonia; nitrogen-containing electron donors such as ammonia, amines, nitriles and isocyanates can be used. Of these electron donor components, esters of inorganic acids and ethers are preferred.

The inorganic acid ester is preferably a general formula R ⁹ _n Si (OR ¹⁰ ) _4-n (wherein R ⁹ is a hydrocarbon group or hydrogen atom having 1 to 20 carbon atoms, and R ¹⁰ is 1 to 1 carbon atom). 20 is a silicon compound represented by the following formula: n is 0 ≦ n <4. Specific examples include tetrabutoxysilane, butyltrimethoxysilane, tert-butyl-n-propyldimethoxysilane, dicyclopentyldimethoxysilane, cyclohexylethyldimethoxysilane, and the like.

（式中、Ｒ^１１〜Ｒ^１４は炭素数１〜２０の線状又は分岐状のアルキル基、脂環式炭化水素基、アリール基、又はアラルキル基であり、Ｒ^１１又はＲ^１２は水素原子であってもよい。）で表されるジエーテル化合物があげられる。具体例としては、ジブチルエーテル、ジアミルエーテル、２，２−ジイソブチル−１，３−ジメトキシプロパン、２，２−ジシクロペンチル−１，３−ジメトキシプロパン等をあげることができる。 The ethers are preferably dialkyl ethers, general formula

(Wherein R ^{11 to} R ¹⁴ are a linear or branched alkyl group having 1 to 20 carbon atoms, an alicyclic hydrocarbon group, an aryl group, or an aralkyl group, and R ¹¹ or R ¹² is a hydrogen atom. May be present). Specific examples include dibutyl ether, diamyl ether, 2,2-diisobutyl-1,3-dimethoxypropane, 2,2-dicyclopentyl-1,3-dimethoxypropane, and the like.

Among these electron donor components, an organosilicon compound represented by the general formula R ¹⁵ R ¹⁶ Si (OR ¹⁷ ) ₂ is particularly preferably used. Here, in the formula, R ¹⁵ is a hydrocarbon group having 3 to 20 carbon atoms in which the carbon atom adjacent to Si is secondary or tertiary, specifically, isopropyl group, sec-butyl group, tert-butyl. Group, branched alkyl groups such as tert-amyl group; cycloalkyl groups such as cyclopentyl group and cyclohexyl group; cycloalkenyl groups such as cyclopentenyl group; aryl groups such as phenyl group and tolyl group. In the formula, R ¹⁶ is a hydrocarbon group having 1 to 20 carbon atoms, specifically, a linear alkyl group such as methyl group, ethyl group, propyl group, butyl group, pentyl group; isopropyl group, sec -Branched alkyl groups such as butyl group, tert-butyl group, tert-amyl group; cycloalkyl groups such as cyclopentyl group and cyclohexyl group; cycloalkenyl groups such as cyclopentenyl group; aryls such as phenyl group and tolyl group Group and the like. Further, in the formula, R ¹⁷ is a hydrocarbon group having 1 to 20 carbon atoms, preferably a hydrocarbon group having 1 to 5 carbon atoms. Specific examples of the organosilicon compound used as such an electron donor component include tert-butyl-n-propyldimethoxysilane, dicyclopentyldimethoxysilane, cyclohexylethyldimethoxysilane, and the like.

  In the preparation of the Ziegler-based solid catalyst, the amount of the organoaluminum compound component used is usually 1-1000 mol, preferably 5-800 mol, per 1 mol of titanium atoms contained in the catalyst component (A). The amount of the electron donor component used is usually 0.1 to 2000 mol, preferably 0.3 to 1000 mol, more preferably 0.5 to 1 mol per mol of titanium atoms contained in the catalyst component (A). 800 moles.

  The catalyst component (A), the organoaluminum compound component, and the electron donor component may be contacted in advance before being supplied to the multistage polymerization reaction apparatus, and separately supplied to the multistage polymerization reaction apparatus. You may make it contact. Further, any two of these components may be brought into contact with each other, and then another component may be brought into contact with each other. Each component may be brought into contact several times.

Examples of the metallocene compound used for the preparation of the metallocene solid catalyst include transition metal compounds represented by the following general formula.
L _x M
(In the formula, M represents a transition metal. X represents a number satisfying the valence of the transition metal M. L is a ligand coordinated to the transition metal, and at least one of L is cyclopentadidi. (It is a ligand having an enyl skeleton.)

  The M is preferably a group 3-6 atom of the Periodic Table of Elements (IUPAC 1989), more preferably titanium, zirconium, or hafnium.

  Examples of the ligand having a cyclopentadienyl skeleton of L include a (substituted) cyclopentadienyl group, a (substituted) indenyl group, and a (substituted) fluorenyl group. Specifically, a cyclopentadienyl group, Methylcyclopentadienyl group, tert-butylcyclopentadienyl group, dimethylcyclopentadienyl group, tert-butyl-methylcyclopentadienyl group, methyl-isopropylcyclopentadienyl group, trimethylcyclopentadienyl group, Tetramethylcyclopentadienyl group, pentamethylcyclopentadienyl group, indenyl group, 4,5,6,7-tetrahydroindenyl group, 2-methylindenyl group, 3-methylindenyl group, 4-methylindene Nyl group, 5-methylindenyl group, 6-methylindenyl group, 7-methylin Nyl group, 2-tert-butylindenyl group, 3-tert-butylindenyl group, 4-tert-butylindenyl group, 5-tert-butylindenyl group, 6-tert-butylindenyl group, 7- tert-butylindenyl group, 2,3-dimethylindenyl group, 4,7-dimethylindenyl group, 2,4,7-trimethylindenyl group, 2-methyl-4-isopropylindenyl group, 4,5 -Benzindenyl group, 2-methyl-4,5-benzindenyl group, 4-phenylindenyl group, 2-methyl-5-phenylindenyl group, 2-methyl-4-phenylindenyl group, 2-methyl-4- Naphthylindenyl group, fluorenyl group, 2,7-dimethylfluorenyl group, 2,7-di-tert-butylfluorenyl group, and their positions Body, and the like. Moreover, when there are a plurality of ligands having a cyclopentadienyl skeleton, they may be the same as or different from each other.

  Among L, as a ligand other than a ligand having a cyclopentadienyl skeleton, a group containing a hetero atom, a halogen atom, a hydrocarbon group (here, a group having a cyclopentadiene-type anion skeleton is included) Not).

  Examples of the hetero atom in the group containing a hetero atom include an oxygen atom, a sulfur atom, a nitrogen atom, and a phosphorus atom. Examples of such a group include an alkoxy group; an aryloxy group; a thioalkoxy group; a thioaryloxy group; An alkylamino group; an arylamino group; an alkylphosphino group; an arylphosphino group; an aromatic or aliphatic heterocyclic group having at least one atom selected from an oxygen atom, a sulfur atom, a nitrogen atom and a phosphorus atom in the ring, etc. Can be given. Specific examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom. Examples of the hydrocarbon group include an alkyl group, an aralkyl group, an aryl group, and an alkenyl group.

  Two or more Ls may be directly linked and linked via a residue containing at least one atom selected from a carbon atom, a silicon atom, a nitrogen atom, an oxygen atom, a sulfur atom, and a phosphorus atom. It may be. Examples of such residues include alkylene groups such as methylene group, ethylene group, propylene group; substituted alkylene groups such as dimethylmethylene group (isopropylidene group) and diphenylmethylene group; silylene group; dimethylsilylene group, diethylsilylene group, Substituted silylene groups such as diphenylsilylene group, tetramethyldisilylene group, dimethoxysilylene group; heteroatoms such as nitrogen atom, oxygen atom, sulfur atom, phosphorus atom and the like, particularly preferably methylene group, ethylene group, dimethylmethylene Group (isopropylidene group), diphenylmethylene group, dimethylsilylene group, diethylsilylene group, diphenylsilylene group or dimethoxysilylene group.

  Examples of metallocene compounds include bis (cyclopentadienyl) zirconium dichloride, bis (methylcyclopentadienyl) zirconium dichloride, bis (indenyl) zirconium dichloride, bis (4,5,6,7-tetrahydroindenyl) zirconium. Dichloride, ethylenebis (indenyl) zirconium dichloride, dimethylsilylenebis (trimethylcyclopentadienyl) zirconium dichloride, dimethylsilylenebis (indenyl) zirconium dichloride, dimethylsilyl (tetramethylcyclopentadienyl) (3,5-di-tert -Butyl-2-phenoxy) titanium dichloride and the like. Moreover, the compound which substituted dichloride with groups, such as dimethoxide and diphenoxide, can also be illustrated.

  Examples of the promoter component used for the preparation of the metallocene-based solid catalyst include organoaluminum oxy compounds, organoaluminum compounds, and boron compounds.

  Examples of the organoaluminum oxy compound include tetramethyldialuminoxane, tetraethyldialuminoxane, tetrabutyldialuminoxane, tetrahexyldialuminoxane, methylaluminoxane, ethylaluminoxane, butylaluminoxane, hexylaluminoxane and the like.

  Examples of the organoaluminum compound include trimethylaluminum, triethylaluminum, trinormalbutylaluminum, triisobutylaluminum, and trinormalhexylaluminum.

  Examples of the boron compound include tris (pentafluorophenyl) borane, triphenylcarbenium tetrakis (pentafluorophenyl) borate, tri (n-butyl) ammonium tetrakis (pentafluorophenyl) borate, N, N-dimethylanilinium tetrakis ( And pentafluorophenyl) borate.

As the particulate carrier used for the preparation of the metallocene solid catalyst, a porous material is preferable, and SiO ₂ , Al ₂ O ₃ , MgO, ZrO ₂ , TiO ₂ , B ₂ O ₃ , CaO, ZnO, BaO, ThO. Inorganic oxides such as ₂ ; clays and clay minerals such as smectite, montmorillonite, hectorite, laponite, and saponite; organic polymers such as polyethylene, polypropylene, and styrene-divinylbenzene copolymer are used.

  Examples of the metallocene solid catalyst include JP-A-60-35006, JP-A-60-35007, JP-A-60-35008, JP-A-61-108610, JP-A-61-. 276805, JP-A 61-296008, JP-A 63-89505, JP 3-234709, JP 5-502906, JP 6-336502, JP 7 -224106 gazette etc. can be used.

  Further, the metallocene-based solid catalyst may be used together with a promoter component such as an organoaluminum compound and a boron compound as necessary in the polymerization of olefin, and when used in combination, the metallocene-based solid catalyst and the promoter component are You may make it contact before supplying to a polymerization reaction apparatus previously, and you may supply separately to a polymerization reaction apparatus and you may make it contact in a polymerization reaction apparatus. In addition, each component may be contacted separately in multiple times.

  The mass average particle diameter of the above olefin polymerization catalyst is usually 5 to 150 μm. In particular, in the gas phase polymerization reaction apparatus, those having a size of 10 μm or more are preferably used, and those having a size of 15 μm or more are more preferably used from the viewpoint of suppressing particle scattering outside the apparatus. In addition, the polymerization catalyst of this embodiment may contain additives such as fluidization aids and static electricity removal additives. Further, the polymerization catalyst of this embodiment can be used in combination with a chain transfer agent such as hydrogen in order to adjust the molecular weight of the polymer.

  The above olefin polymerization catalyst may be a so-called prepolymerization catalyst that is preliminarily polymerized with a small amount of olefins. Examples of the olefins used in the prepolymerization include the olefins used in the above-described polymerization. In this case, one type of olefin may be used alone, or two or more types of olefins may be used in combination.

  A method for producing the prepolymerization catalyst is not particularly limited, and examples thereof include slurry polymerization and gas phase polymerization. Of these, slurry polymerization is preferred. In this case, it may be economically advantageous in manufacturing. Moreover, you may manufacture using any of a batch type, a semibatch type, and a continuous type.

  The mass average particle diameter of the prepolymerized catalyst is usually 5 to 1000 μm. In particular, in the gas phase polymerization reaction apparatus, those having a size of 10 μm or more are preferably used, and those having a size of 15 μm or more are more preferably used from the viewpoint of suppressing scattering outside the apparatus. Further, it is preferable that the number of prepolymerization catalysts having a particle size of 20 μm or less, particularly 10 μm or less is small.

  The polymerization catalyst may be introduced into the reaction apparatus by suspending it in a hydrocarbon solvent, or may be introduced together with an inert gas such as monomer gas or nitrogen.

(Polyolefin production method)
Subsequently, a method for producing polyolefin using such a system will be described. First, in the olefin prepolymerization reaction apparatus 5, polyolefin particles containing a catalyst component having polymerization activity are generated by a known method using an olefin polymerization catalyst.

  On the other hand, in the olefin polymerization reaction apparatus 10A, the olefin monomer gas is supplied from the nozzle 38 via the line L30, the pressure is increased to the polymerization pressure, and the inside of the cylinder 12 is heated. The polymerization pressure may be within the range in which the olefin can exist as a gas phase in the reaction apparatus, and is usually normal pressure to 10 MPaG, more preferably 0.2 to 8 MPaG, and further preferably 0.5 to 5 MPaG. This is because if the polymerization pressure is less than normal pressure, the productivity may decrease, and if the reaction pressure exceeds 10 MPaG, the equipment cost of the reaction apparatus may increase. The polymerization temperature varies depending on the type of monomer, the molecular weight of the product, etc., but is a temperature not higher than the melting point of the olefin polymer, preferably 10 ° C. or lower than the melting point. Specifically, 0 to 120 ° C is preferable, 20 to 100 ° C is more preferable, and 40 to 100 ° C is still more preferable. Moreover, it is preferable to perform the polymerization in an environment substantially free of moisture. In the presence of moisture, the polymerization activity of the polymerization catalyst may decrease. Moreover, when oxygen, oxygen monoxide, and carbon dioxide are excessively present in the polymerization reaction system, the polymerization activity may be lowered.

  Thereafter, polyolefin particles having a particle size of about 0.5 to 5.0 mm separately obtained by a known method are supplied into the cylinder 12 through a supply line (not shown) connected to the line L5. Usually, the polyolefin particles supplied into the cylinder 12 are often used without containing a catalyst component having polymerization activity, but may contain a catalyst component having polymerization activity.

  When polyolefin particles are supplied into the cylinder 12 while supplying the olefin monomer gas from the nozzle 38, a spouted layer of polyolefin particles is formed in the reaction region 25 as shown in FIG. That is, by the action of the gas from the gas introduction opening, a jet flow in which the particle concentration is dilute near the central axis of the cylinder 12 in the reaction region 25 and the particles flow upward together with this gas is formed. Is formed in a moving layer shape under the influence of gravity, and a circulating motion of particles occurs in the reaction region 25.

  At the stage where the spouted bed is formed in each reaction region 25, polyolefin particles containing a catalyst component having polymerization activity generated in the pre-polymerization reactor 5 are supplied into the cylinder 12 from the line L5 in a constant amount per unit time. Then, the steady operation of the olefin polymerization reactor 10A is started. While growing in each reaction region 25, the polyolefin particles containing the catalyst component having polymerization activity are sequentially lowered into the lower reaction region 25 through the downcomer tube 35a, and finally discharged from the downcomer tube 35b. .

  On the other hand, part of the gas containing the olefin monomer forms a jet and blows through the particle layer, and the rest diffuses into the part of the particle layer having an annular structure. Thus, the olefin-containing gas and the polyolefin particles come into solid-gas contact, and the olefin polymerization reaction proceeds by the action of the catalyst in the polyolefin particles, and the polyolefin particles grow.

式中、ｄ_Ｐは粒径を、ρ_Ｓは粒子の密度を、ρ_Ｇは反応領域の圧力・温度条件下におけるガスの密度を、ρ_ＡＩＲは室温条件下における空気の密度を、Ｌ_Ｓは噴流層高さを、それぞれ示す。 In order to form a stable spouted bed in each reaction region 25, it is preferable to satisfy the following operating conditions. That is, it is the minimum gas superficial velocity Ums or more gas superficial velocity U ₀ can form a spouted bed. The minimum gas superficial velocity Ums is influenced by the shape of the polymerization reaction apparatus in addition to the physical properties of the handled powder and gas. Various formulas for estimating the minimum gas superficial velocity Ums have been proposed, and the following formula (1) can be given as an example.

Where d _P is the particle size, ρ _S is the particle density, ρ _G is the gas density under the pressure and temperature conditions in the reaction zone, ρ _AIR is the air density at room temperature, and L _S is The spouted bed height is shown respectively.

式中、ｕ_ｔは粒子の終末速度を、ｕ_ｍｆは最小流動化速度を、それぞれ示す。 In addition, the spouted bed height L _S in the reaction region 25 is not more than the maximum spouted bed height Ls _MAX m that can form a spouted bed and is not more than the maximum spouted bed height Ls _MAX . Various formulas for estimating the maximum spouted bed height Ls _MAX have been proposed, and the following formula (2) can be given as an example.

In the formula, u _t represents the end velocity of the particles, and u _mf represents the minimum fluidization velocity.

The spouted bed height L _S is preferably higher than the cylindrical baffle 30 from the viewpoint of forming volumetric efficiency and a more stable spouted bed.

  Further, as shown in FIG. 1, after condensing all or part of the gas containing olefin extracted from the olefin polymerization reaction apparatus to obtain a condensate, the condensate is discharged from the middle nozzle 50 of the cylinder 12 to the cylinder 12. May be supplied. In this case, the olefin monomer consumed by the polymerization reaction can be replenished. In addition to this, when the liquid olefin monomer evaporates in the cylinder 12, it is possible to remove heat from the polyolefin particles by latent heat of vaporization. In the plurality of reaction regions 25 in the cylinder 12, the upper reaction region 25 is likely to be heated to a higher temperature due to reaction heat, and a temperature difference from the lower reaction region 25 occurs. Therefore, by supplying the liquid olefin monomer from the nozzle 50 provided in the middle stage of the cylinder 12, the temperature difference can be suppressed to the minimum, and the temperature can be made uniform.

  According to the olefin polymerization reaction apparatus 10A according to the present embodiment, by arranging the draft tube T1 in the reaction region 25, both high stability of the spouted bed and reduction of pressure loss can be achieved. Furthermore, high gas diffusibility to the annular particle layer can be achieved by appropriately setting the diameter, length, clearance, and the like of the draft tube T1.

  According to the olefin polymerization reactor 10A, a multistage spouted bed is formed in the cylinder 12, and the residence time distribution of the particles can be narrowed. Accordingly, when the olefin polymer is continuously produced, it is possible to produce a polymer having excellent uniformity on the polymer structure. Further, when changing the production conditions, the polyolefin particles polymerized before the change of conditions can be easily discharged from the container, so that the amount of non-standard products generated can be sufficiently reduced. Moreover, since the baffle plate 20 which suppresses scattering of the jetted particle is provided, a free board zone can be shortened and high volumetric efficiency can be achieved.

  In addition, this invention is not limited to the said embodiment. For example, in the above-described embodiment, the case where the downcomer tube 35a is employed as the transfer means for transferring the polyolefin particles from the upstream reaction region to the downstream reaction region is exemplified. Particles may be transferred. The olefin polymerization reaction apparatus 10B of the polyolefin production system 100B shown in FIG. 3 includes ejector-type transfer means. In addition, although not shown, a transfer means called a double damper or a double bubble system may be used in which two open / close valves are provided apart from the flow passage to transfer powder.

  The transfer means of the olefin polymerization reaction apparatus 10B includes a particle extraction pipe L31 for extracting polyolefin particles from the upstream reaction region 25, an ejector 32 provided at the tip of the particle extraction pipe L31, and a polyolefin particle from the ejector 32. And a particle supply pipe L33 for supplying the gas to the downstream reaction region 25. An open / close valve is provided in the middle of the particle extraction pipe L31. Further, the ejector 32 and the gas-liquid separator 66 are connected by a line L36 in which a compressor (not shown) is disposed in the middle, and a part of the recycled gas separated by the gas-liquid separator 66 is ejected. Supplied as working gas. 3 illustrates the transfer of the polyolefin particles from the upper stage to the lower stage, but it is also possible to transfer the polyolefin particles from the lower stage to the upper stage in the direction opposite to the vertical direction by adjusting the differential pressure generated in the ejector. is there. That is, in this case, the upstream reaction region is arranged at the lower stage, and the downstream reaction region is arranged at the upper stage.

  In the above embodiment, the olefin polymerization reaction apparatus in which the five-stage spouted bed is formed in the vertical direction is illustrated, but the number of spouted bed stages is not limited to this and may be a single stage. However, from the viewpoint of realizing sufficient plug flow, the number of spouted bed stages is preferably 3 or more, and more preferably 6 or more. Furthermore, the multi-stage spouted bed does not necessarily have to be formed in the vertical direction. For example, a plurality of reaction apparatuses in which a single-stage spouted bed is formed are installed in the horizontal direction, and these reaction apparatuses are connected in series. You may connect. Regarding the device design and operation control method, each device (including the olefin prepolymerization reaction device 5) is made more uniform in each stage so that the residence time distribution of the polyolefin particles becomes narrower. It is preferable to design the capacity of the stage and control the hold-up and residence time of the polyolefin particles.

  Moreover, in the said embodiment, although the case where the liquid supply nozzle 50 was arrange | positioned in the vicinity of the gas introduction opening of the cylindrical baffle 30 of the 2nd step from the top was illustrated, the arrangement | positioning location and number of the liquid supply nozzle 50 are as follows. What is necessary is just to set suitably according to the kind etc. of the polyolefin particle to manufacture. For example, if the temperature of each reaction region 25 can be made uniform by other means, the liquid supply nozzle 50 does not necessarily have to be disposed, or the liquid is provided in the vicinity of the gas introduction openings of all the cylindrical baffles 30. Each supply nozzle 50 may be disposed.

  Further, the downcomer tubes 35a and 35b illustrated in the above embodiment have upper ends protruding to the upper side of the cylindrical baffle 30, but the outer surfaces of these downcomer tubes 35a and 35b and the inner surface of the cylinder 12 or When the flow of polyolefin particles between the inner surfaces of the cylindrical baffles 30 is hindered, the downcomer tubes 35a and 35b may be configured not to protrude upward from the inner surfaces of the cylindrical baffles 30. . In this case, a mechanism (for example, an on-off valve) for adjusting the amount of particles to be lowered from the upper reaction region 25 to the lower reaction region 25 may be appropriately provided in the downcomer tube.

  With reference to FIG. 4, a preferred configuration of a polyolefin production system that employs a bulk polymerization reactor as the olefin prepolymerization reactor and adopts an ejector system as a transfer means will be described in detail. A polyolefin production system 100C shown in FIG. 4 includes a bulk polymerization reaction apparatus 5 and an olefin polymerization reaction apparatus 10C having an upper stage and a lower reaction area 25 therein.

The bulk polymerization reaction apparatus 5 polymerizes olefins in a liquid phase containing an olefin polymerization catalyst to form polyolefin particles. The polyolefin particles generated in the bulk polymerization reactor 5 are supplied to the olefin polymerization reactor 10C through the line L5 together with the liquid olefin. The nozzle 68 is for supplying slurry to the upper reaction region 25, and is provided at a position lower than the powder surface 85 of the spouted bed, as shown in FIG. When the slurry is supplied into the reaction region 25 from a position lower than the powder surface 85, the superficial velocity after gasification of the liquid olefin contained in the slurry is the minimum fluidization rate of the polyolefin particles contained in the reaction region 25 ( It is preferable to adjust the supply amount of the slurry so that U _mf ) is not exceeded. By adjusting the supply amount of the slurry in this way, it is possible to sufficiently prevent the fluidized state of the spouted bed from becoming unstable as the liquid olefin is gasified in the reaction region 25. The “vacuum speed after gasification of liquid olefin” means that the volume flow rate of liquid olefin supplied to the olefin polymerization reactor is converted to the volume flow rate after gasification, and this is the cylindrical part of the olefin polymerization reactor. the cross-sectional area ^{_{a (a = πD R 2/}} 4, D R is the inner diameter of the cylindrical portion) means a value calculated by dividing.

  In addition, although the structure which supplies a slurry from the position lower than the powder surface 85 was illustrated here, the position which supplies a slurry is not limited to this. For example, the nozzle 68 may be provided at a position higher than the powder surface 85. In this case, even if the amount of slurry supplied per unit time is relatively large, there is an advantage that the fluidized state of the spouted bed can be prevented from becoming unstable as the liquid olefin is gasified.

  As shown in FIG. 4, a gas supply nozzle 38 is provided at the lower part of the cylinder 12, and the olefin monomer is supplied to the lower part of the cylinder 12 via a line L <b> 30. On the other hand, a gas discharge nozzle 61 is provided in the upper part of the cylinder 12. The gas rising in the cylinder 12 is discharged to the outside through the line L40, and gas entrained particles are discharged by the cyclone 62 installed as necessary. After passing through the compressor 64 and the heat exchanger 65, the gas is introduced into the line L30 via the line L35 and recycled.

  As described above, the olefin polymerization reaction apparatus 10 </ b> C includes an ejector-type transfer unit. This transfer means includes a particle extraction tube L31 for extracting polyolefin particles from the upper reaction region 25, an ejector 32 provided at the tip of the particle extraction tube L31, and a polyolefin particle from the ejector 32 in the lower reaction region 25. And a particle supply pipe L33 for supplying to the gas. An on-off valve 80 is provided in the middle of the particle extraction pipe L31. Lines L38 are connected to the particle extraction pipe L31 on the upstream side and downstream side of the on-off valve 80, respectively, so that gas for preventing clogging can be supplied into the particle extraction pipe L31 through the gas supply pipe L38. ing.

  A part of the gas pressurized by the compressor 64 is supplied to the ejector 32 through a line L37. This gas is used as a gas for operating the ejector. A part of the gas pressurized by the compressor 64 is supplied to the particle extraction pipe L31 upstream and downstream of the on-off valve 80 through a line L38. This gas is used as a gas for preventing the on-off valve 80 and the ejector 32 from being clogged.

  In FIG. 4, the polyolefin particles are illustrated as being transferred from the upper stage to the lower stage. However, by adjusting the differential pressure generated in the ejector, it is also possible to transfer the polyolefin particles from the lower stage to the upper stage in the direction opposite to the vertical direction. is there. That is, in this case, the upstream reaction region is arranged at the lower stage, and the downstream reaction region is arranged at the upper stage.

  The flow rate of the ejector operating gas is not particularly limited as long as it is greater than the amount capable of discharging polyolefin particles. On the other hand, the clogging preventing gas is preferably about 10 parts by volume with respect to 100 parts by volume of the ejector operating gas. From the viewpoint of reliably preventing the on-off valve 80 and the ejector 32 from being clogged, the upstream side of the on-off valve 80 through the line L38, regardless of the on-off state of the on-off valve 80, while operating in the olefin polymerization reactor 10C. And it is preferable to always supply gas downstream.

  The olefin polymerization reaction apparatus 10C includes a capacitance level meter 93 and a differential pressure gauge 90 for measuring the height of the spouted bed (position of the powder surface 85). By using the capacitance level meter 93 and the differential pressure meter 90 in combination, the displacement of the powder surface 85 can be grasped more accurately. In order to prevent the connection line of the differential pressure gauge 90 from being blocked, it is preferable to perform line blowing constantly or periodically.

  The olefin polymerization reactor 10D shown in FIG. 5 uses the draft tube T1 in the reaction region 25, and can make the gas composition inside the draft tube T1 different from the gas composition outside the draft tube T1. The olefin polymerization reaction apparatus 10D includes a pipe L25 communicating with the inside of the draft tube T1, through which gas or liquid is supplied into the draft tube T1. For example, it is possible to produce a polymer having a relatively large molecular weight in the draft tube T1 by using a gas composition having a smaller amount of hydrogen compared to the outside of the draft tube T1. By repeatedly passing the particles through regions having different gas compositions and gradually growing the particles, the molecular weight distribution of the polymer can be controlled, and particles having excellent uniformity in the polymer structure can be produced.

  The olefin polymerization reactor 10D is configured to form a single-stage spouted bed, and is mainly disposed in a cylinder 12A extending in the vertical direction, a closing plate 15 closing the upper end of the cylinder 12A, and the cylinder 12A. A deflection plate 20 and a cylindrical baffle 30 provided at the lower end of the cylinder 12A are provided. Both the baffle plate 20 and the cylindrical baffle 30 are preferably arranged coaxially with the axis of the cylinder 12A. A reaction region 25 is formed by the lower surface of the closing plate 15, the inner surface of the cylinder 12 </ b> A, and the inner surface of the cylindrical baffle 30. Gas can be supplied into the reaction region 25 from the gas introduction opening at the lower end of the cylindrical baffle 30. A compressor 54 and a heat exchanger 65 are disposed in the middle of the line L30.

  A gas discharge hole 70 is formed in the cylinder 12 </ b> A forming the side wall surface of the reaction region 25 so that the gas in the reaction region 25 can be discharged. In the olefin polymerization reaction apparatus 10D according to the present embodiment, four gas discharge holes 70 are formed so as to be substantially equidistant along the circumferential direction of the cylinder 12A. The gas flowing upward from the gas introduction opening of the cylindrical baffle 30 is not discharged from the upper side of the reaction region 25 as it is, but is discharged from the four gas discharge holes 70 to the side, The amount of gas diffusing into the annular particle layer can be increased. As a result, the solid-gas contact efficiency between the particles and the olefin-containing gas is improved in the annular particle layer of the spouted bed. The gas discharge hole 70 is preferably above the lower end 20b of the baffle plate 20 in the reaction region 25, and more preferably above the upper end 20a of the baffle plate 20. By providing the gas discharge hole 70 at such a height, particles discharged from the gas discharge hole 70 together with the gas can be sufficiently reduced. Here, although four gas discharge holes 70 are illustrated as being installed here, the number of gas discharge holes 70 is not limited to this. The number of installed gas discharge holes 70 may be more than 4 or less than 4, but is preferably 2 or more in order to perform more uniform gas discharge. Moreover, although the olefin polymerization reaction apparatus 10D forms a single-stage spouted bed, it can also be configured to form a multi-stage spouted bed. In this case, the draft tube T1 and the pipe L25 communicating with the draft tube T1 may be provided in at least one reaction region, or the draft tube T1 and the pipe L25 may be provided in each reaction region.

  In the above-described embodiment, the case where the draft tube T1 (see FIG. 6A) made of a straight pipe is employed is exemplified, but a draft tube having the following configuration may be adopted. For example, a draft tube T2 shown in FIG. 6B has a straight pipe portion T2a extending downward from the upper end opening with a constant diameter, and a diameter-expanded portion T2b having a diameter increasing downward from the edge of the straight pipe portion T2a. And have. By using the draft tube having such a configuration, the stability of the spouted bed and the gas diffusibility to the annular portion may be improved. In addition, from the viewpoint of further improving the gas diffusibility, a plurality of through holes penetrating from the inside to the outside of the draft tube T1 may be provided. Moreover, when providing a some through-hole in draft tube T2, you may provide in the whole, but you may provide only in the enlarged diameter part T2b.

  Moreover, in the said embodiment, although the apparatus of the structure by which the opening for gas introduction was simply formed in the lower end of the cylindrical baffle 30 was illustrated, from a viewpoint of improving the stability of a spouted layer further, a gas introduction part is used. It is good also as the following structures. For example, you may provide the extension pipe (tubular part) 40 extended below from the edge of the opening for gas introduction of the cylindrical baffle 30 (refer FIG. 7). Further, a partition wall or the like extending in the longitudinal direction of the extension tube 40 and partitioning the pipe line 40a in the horizontal direction may be provided inside the extension tube 40. A specific embodiment of such an extension tube is shown in FIGS. FIGS. 8A to 8C are cross-sectional views perpendicular to the longitudinal direction of the extension tube, and the partition 40b of the extension tube 41 shown in FIG. 8A has a lattice structure. The partition wall 40c of the extension pipe 42 shown in FIG. 8B has a honeycomb structure. The partition 40d of the extension pipe 43 shown in FIG. The extension pipe 43 has a structure in which a plurality of cylindrical pipes are arranged in parallel in a pipe line, and has an advantage that it is easier to construct than other structures.

  The partition provided in the pipe line of the extension pipe is not limited to the form shown in FIGS. 8A to 8C, and may be the form shown in FIGS. The partition walls 40b and 40c shown in FIGS. 9A and 9B are formed so that an opening is formed at the center of the extension pipe. The extension pipes 44 and 45 shown in FIGS. 10 (a) and 10 (b) are ones in which one or two cylindrical members are coaxially arranged in the pipe line, and partition walls 40e and 40f are formed by these. Yes.

Instead of providing a partition wall in the pipe line 40a of the extension pipe 40, as shown in FIG. 11, the gas introduction part may be formed by coaxially arranging a cylindrical member 46 whose upper end is closed in the pipe line 40a. . By arranging the cylindrical member 46 in the conduit 40 a, an annulus 46 a is formed by the outer surface of the cylindrical member 46 and the inner surface of the extension tube 40. By adopting such a configuration, the horizontal cross section of the pipe line 40a can be formed into a ring shape. As a result, compared with the case where a pipe having the same cross-sectional area as that of the annulus 46a and a circular cross section is adopted, the pushing-up effect on the particles that are likely to fall downward from the gas introduction opening is improved, and the pipe drops. Particles can be further reduced. When the diameter of a circle and _{D OE} having the same area as the opening area of the annulus 46a, the ratio to the inner diameter _{D R} of the cylinder 12 of diameter _{D OE (D OE / D R} ) is preferably at 0.35 or less . From the viewpoint of suppressing turbulence of the gas flow, the upper side of the cylindrical member 46 is preferably tapered as shown in FIG. The cylindrical member 46 only needs to have at least one end closed, and may have a lower end or both ends closed.

  Further, the configuration of the gas introduction unit may be as shown in FIG. The extension pipe 40 shown in FIG. 12 includes a closing plate 47 that closes the lower end thereof, and a gas introduction pipe 48 that has a pipe line 48 a that is thinner than the pipe line 40 a and is provided so as to penetrate the closing plate 47. Further, a conical baffle (second conical baffle) 23 is disposed immediately above the upper end of the gas introduction pipe 48. The conical baffle 23 has an outer diameter that increases toward the lower side, is closed at the upper end, and is spaced from the inner surface of the extension tube 40 at the lower end. By adopting such a configuration, since the conical baffle 23 serves as a particle fall prevention plate, it is possible to sufficiently prevent the particles from falling through the gas introduction opening even when the gas supply is stopped. . From the viewpoint of further stabilizing the flow state of the spouted bed, the conical baffle 23 preferably has a cylindrical portion 23c extending downward from the peripheral edge at the lower end thereof, as shown in FIG.

  Moreover, it is good also considering the lower end part of the extension pipes 40-45 as a bell mouth shape. FIG. 14 shows an extension tube 49 having a lower end portion 40g having a bell mouth shape. By adopting the extension pipe having the partition wall, the annulus part and / or the bellmouth shaped lower end part as described above, the effect of pushing up the particles which are likely to fall downward from the gas introduction opening of the cylindrical baffle 30 is improved. In addition, falling particles can be further reduced.

  In the present invention, the draft tube and the gas introduction part having a suitable shape are selected according to the characteristics (average particle diameter, specific gravity, shape, etc.) of the particles to be brought into contact with the gas and the reaction conditions (temperature, pressure, gas supply amount, etc.). The configurations can be used in appropriate combinations.

  In order to evaluate the stability of the spouted bed formed in the reaction region of the olefin polymerization reactor according to the present invention, the pressure loss, and the solid-gas contact efficiency between the particles and the gas in the annular particle layer, examples and comparative examples were performed. It was. The stability of the spouted bed was evaluated from the average deviation of pressure fluctuations. In addition, the evaluation of the solid-gas contact efficiency between particles and gas is performed by comparing the value (Ua / Umf) obtained by dividing the gas flow velocity (Ua) in the annular particle layer by the minimum fluidization velocity (Umf) of the particles. Was done by.

<Examples 1a to 3a and Comparative Example 1a>
Example 1a
A cylindrical cold model device made of transparent vinyl chloride resin capable of forming a single-stage spouted bed was prepared. In this apparatus, a set of a combination of an inverted conical cylindrical baffle having a gas introduction orifice and a conical baffle plate (first conical baffle) is arranged in a cylinder. The configuration of the gas introduction unit was as shown in FIG.

The inner diameter _{D R} of the cylindrical cold model apparatus and 500 mm, the opening diameter _{D O} of the gas inlet orifice of the tubular baffle lower end was 75 mm. Accordingly, in the present embodiment, the ratio of the inner diameter _{D R} of the cylinder of the opening diameter _{D O} of the orifice for gas introduction _(D O / _{D R)} is 0.15. In addition, the inclination angle formed by the inner surface of the inverted conical cylindrical baffle and the horizontal plane and the inclination angle formed by the outer surface of the baffle plate and the horizontal plane were both 65 °. Further, the conical deflector has an outer diameter of 300 mm at the lower end and is hollow inside. The central axis of the cylindrical device was placed inside diameter 75mm made the same as the opening diameter D _O of the gas inlet orifice, a draft tube of length 550mm in the position of 60mm upwardly from the gas inlet orifice.

This apparatus was filled with 30 kg of polypropylene particles having an average particle size of 900 μm, and gas was supplied from the gas introduction orifice to evaluate the flow state of the polypropylene particles. The minimum fluidization speed (Umf) of the polypropylene particles was 0.20 m / s. The introduced gas was room temperature air and was supplied at 5.4 m ³ per minute.

  In the present embodiment, a jet (spout) is formed in which the particle concentration is dilute and the gas flows upward together with the gas in the draft tube installed on the central axis of the cylinder, and the particles form an annular particle layer around it. A descending flow state of the spouted bed was observed. In this state, the pressure (corresponding to the pressure loss of the entire spouted bed) of the in-cylinder gas supply portion at a position 50 mm below from the upper end of the cylindrical baffle (joint portion between the cylinder and the cylindrical baffle) was measured. The pressure is 200 Hz from the differential pressure from the atmospheric pressure using a high-performance differential pressure transducer (PD-200GA manufactured by Kyowa Denki Co., Ltd.) so that it can be quantitatively evaluated including the fluctuation range. The frequency was measured. The pressure was obtained by averaging the measured values, and the pressure fluctuation range was evaluated by the average deviation of the measured values. Further, the pressure in the cylinder (near the inner surface) at a position 50 mm above from the upper end of the cylindrical baffle (joint portion between the cylinder and the cylindrical baffle) is measured by the same method, and is formed above this position. The height of the particle layer was measured, and the pressure loss per unit height in the annular particle layer was calculated. Note that when calculating the pressure loss per unit height in the annular particle layer, Ergun's formula that can estimate the pressure loss of the particle packed layer was used by regarding the formed annular particle layer as a particle packed layer. The gas superficial velocity corresponding to the measured pressure loss was calculated, and this gas superficial velocity was taken as the gas flow velocity (Ua) in the annular particle layer.

  As a result, in this example, the pressure loss of the spouted bed is 1.3 kPa, and the average deviation of pressure fluctuation is 0.023 kPa. The formed spouted bed has little pressure loss, and the pressure fluctuation width is very stable. It was something. The gas flow rate in the annular particle layer was calculated to be 0.023 m / s, which was 0.12 times the minimum fluidization speed.

Example 2a
Evaluation was performed in the same manner as in Example 1a except that the length of the draft tube was set to 460 mm without changing the installation position of the upper end, and the installation was performed 150 mm above the gas introduction orifice. As a result, the pressure loss of the spouted bed is 1.9 kPa, and the average deviation of the pressure fluctuation is 0.10 kPa, which is inferior to Example 1a, but the formed spouted bed has a small pressure loss and a stable pressure fluctuation range. It was something. Further, the gas flow rate in the annular particle layer was calculated to be 0.046 m / s, 0.23 times the minimum fluidization speed, and in this respect, the performance exceeded that of Example 1a.

(Example 3a)
Evaluation was performed in the same manner as in Example 1a except that the length of the draft tube was set to 150 mm without changing the installation position of the upper end, and the installation was performed at a position 460 mm above the gas introduction orifice. As a result, the pressure loss of the spouted bed is 2.3 kPa, and the average deviation of pressure fluctuation is 0.31 kPa, which is inferior to Example 1a, but the formed spouted bed has little pressure loss and a stable pressure fluctuation range. It was something. Further, the gas flow rate in the annular particle layer was calculated to be 0.080 m / s, 0.40 times the minimum fluidization speed, and in this aspect, the performance exceeded that of Example 1a.

(Comparative Example 1a)
Evaluation was performed in the same manner as in Example 1a except that no draft tube was installed in the reaction region. As a result, the annular portion gas velocity showed a high value of 0.110 m / s, but the formed spouted bed had a large pressure loss, a wide pressure fluctuation range, and a relatively unstable one.

<Examples 1b to 3b and Comparative Example 1b>
Examples 1b to 3b and the comparison were performed under the same conditions as in Examples 1a to 3a and Comparative Example 1a except that the gas superficial velocity U was set to 0.59 m / s instead of 0.46 m / s. Example 1b was carried out respectively. Table 2 shows the results.

<Examples 1c to 3c and Comparative Example 1c>
Examples 1c to 3c and the comparison were performed under the same conditions as in Examples 1a to 3a and Comparative Example 1a except that the gas superficial velocity U was set to 0.34 m / s instead of 0.46 m / s. Example 1c was carried out respectively. Table 3 shows the results.

<Examples 4a to 7a and Comparative Example 2a>
Example 4a
A cylindrical cold model device having the same configuration as that used in Example 1a was prepared except that the gas introduction unit was configured as shown in FIG. That is, an extension pipe (length: 100 mm, inner diameter: 150 mm) extending downward from the edge of the gas introduction orifice (opening diameter D _O : 150 mm) at the lower end of the cylindrical baffle was provided. Further, a cylindrical member (outer diameter: 110 mm) whose upper end is closed is mounted in the extension pipe, so that air is supplied into the apparatus through an annulus formed by the inner surface of the extension pipe and the outer surface of the cylindrical member. I made it.

The inner diameter _{D R} of the cylindrical cold model apparatus with 500 mm, therefore, in the present embodiment, the ratio of the inner diameter _{D R} of the cylinder of the opening diameter _{D O} of the orifice for gas introduction _(D O / _{D R)} is 0.30 is there. Incidentally, the equivalent diameter _{D OE} annulus opening area basis of the orifice for gas introduction is 102 mm, the ratio to the inner diameter _{D R} of the cylinder of diameter _{D OE (D OE / D R} ) is 0.20. In addition, the inclination angle formed by the inner surface of the inverted conical cylindrical baffle and the horizontal plane and the inclination angle formed by the outer surface of the baffle plate and the horizontal plane were both 65 °. Further, the conical deflector has an outer diameter of 300 mm at the lower end and is hollow inside. The central axis of the cylindrical device was placed inside diameter 150mm made the same as the opening diameter D _O of the gas inlet orifice, a draft tube of length 590mm in the position of 120mm upward from the gas inlet orifice.

This apparatus was filled with 30 kg of polypropylene particles, and air at room temperature was supplied from the gas introduction orifice at 5.4 m ³ per minute to evaluate the flow state of the polypropylene particles. As the polypropylene particles, those having an average particle diameter of 900 μm and a minimum fluidization speed Umf of 0.20 m / s were used as in Example 1a.

  In the present embodiment, a jet (spout) is formed in which the particle concentration is dilute and the gas flows upward together with the gas in the draft tube installed on the central axis of the cylinder, and the particles form an annular particle layer around it. A descending flow state of the spouted bed was observed. In this example, the pressure loss of the spouted bed was 0.71 kPa, and the average deviation of pressure fluctuation was 0.21 kPa. The gas flow rate in the annular particle layer was calculated to be 0.015 m / s, which was 0.08 times the minimum fluidization rate.

(Example 5a)
Evaluation was performed in the same manner as in Example 4a except that the length of the draft tube was set to 420 mm without changing the position of the lower end. As a result, the pressure loss of the spouted bed was 0.72 kPa, and the average deviation of pressure fluctuation was 0.15 kPa. The gas flow rate in the annular particle layer was calculated to be 0.021 m / s, which was 0.11 times the minimum fluidization rate.

Example 6a
Evaluation was performed in the same manner as in Example 5a except that the length of the draft tube was set to 300 mm without changing the installation position of the upper end. As a result, the pressure loss of the spouted bed was 1.1 kPa, and the average deviation of pressure fluctuation was 0.17 kPa. The gas flow rate in the annular particle layer was calculated to be 0.044 m / s, which was 0.22 times the minimum fluidization speed.

(Example 7a)
Evaluation was performed in the same manner as in Example 6a except that the length of the draft tube was set to 150 mm without changing the installation position of the upper end. As a result, the pressure loss of the spouted bed was 1.7 kPa, and the average deviation of the pressure fluctuation was 0.56 kPa. The gas flow rate in the annular particle layer was calculated to be 0.091 m / s, which was 0.46 times the minimum fluidization speed.

(Comparative Example 2a)
Evaluation was performed in the same manner as in Example 4a except that no draft tube was installed in the reaction region. As a result, the annular portion gas velocity showed a high value of 0.120 m / s, but the formed spouted bed had a large pressure loss, a wide pressure fluctuation range, and was relatively unstable.

<Examples 4b to 7b and Comparative Example 2b>
Instead of setting the gas superficial velocity U to 0.46 m / s, except that it was set to 0.59 m / s, Examples 4b to 7b and Comparative Example were compared under the same conditions as in Examples 4a to 7a and Comparative Example 2a. Example 2b was carried out respectively. Table 5 shows the results.

<Examples 4c to 7c and Comparative Example 2c>
Examples 4c to 7c and the comparison were made under the same conditions as in Examples 4a to 7a and Comparative Example 2a except that the gas superficial velocity U was set to 0.34 m / s instead of 0.46 m / s. Example 2c was performed respectively. Table 6 shows the results.

<Examples 8a to 11a>
(Example 8a)
Instead of a straight pipe draft tube, a draft tube having a straight pipe portion extending downward from the upper end with a constant diameter and a diameter-expanding portion whose diameter increases downward from the edge of the straight pipe portion is used. Prepared a cylindrical cold model device having the same configuration as that used in Example 1a (see FIGS. 6B and 7). In this example, a draft tube having the configuration shown in the column of Example 8a in Table 7 was installed at a position 270 mm above the gas introduction orifice on the central axis of the cylindrical device.

This apparatus was filled with 30 kg of polypropylene particles having an average particle size of 900 μm, and gas was supplied from the gas introduction orifice to evaluate the flow state of the polypropylene particles. The minimum fluidization speed (Umf) of the polypropylene particles was 0.20 m / s. The introduced gas was room temperature air and was supplied at 5.4 m ³ per minute.

  In the present embodiment, a jet (spout) is formed in which the particle concentration is dilute and the gas flows upward together with the gas in the draft tube installed on the central axis of the cylinder, and the particles form an annular particle layer around it. A descending flow state of the spouted bed was observed. In this example, the pressure loss of the spouted bed was 1.9 kPa, and the average deviation of pressure fluctuation was 0.14 kPa. The gas flow rate in the annular particle layer was calculated to be 0.059 m / s, which was 0.30 times the minimum fluidization speed.

Example 9a
Instead of a straight pipe draft tube, a draft tube having a straight pipe portion extending downward from the upper end with a constant diameter and a diameter-expanding portion whose diameter increases downward from the edge of the straight pipe portion is used. Prepared a cylindrical cold model device having the same configuration as that used in Example 4a (see FIGS. 6B and 11). In this example, a draft tube having the structure shown in the column of Example 9a in Table 7 was installed at a position 270 mm above the gas introduction orifice on the central axis of the cylindrical device.

This apparatus was filled with 30 kg of polypropylene particles having an average particle size of 900 μm, and gas was supplied from the gas introduction orifice to evaluate the flow state of the polypropylene particles. The minimum fluidization speed (Umf) of the polypropylene particles was 0.20 m / s. The introduced gas was room temperature air and was supplied at 5.4 m ³ per minute.

  In the present embodiment, a jet (spout) is formed in which the particle concentration is dilute and the gas flows upward together with the gas in the draft tube installed on the central axis of the cylinder, and the particles form an annular particle layer around it. A descending flow state of the spouted bed was observed. In this example, the pressure loss of the spouted bed was 1.2 kPa, and the average deviation of pressure fluctuation was 0.37 kPa. The gas flow rate in the annular particle layer was calculated to be 0.129 m / s, which was 0.65 times the minimum fluidization speed.

Example 10a
Evaluation was performed in the same manner as in Example 9a, except that the configuration of the draft tube was changed to that shown in the column of Example 10a in Table 7 without changing the installation position of the lower end. As a result, the pressure loss of the spouted bed was 1.1 kPa, and the average deviation of pressure fluctuation was 0.36 kPa. The gas flow rate in the annular particle layer was calculated to be 0.143 m / s, which was 0.72 times the minimum fluidization speed.

Example 11a
Evaluation was performed in the same manner as in Example 9a except that the configuration of the draft tube was changed to that shown in the column of Example 11a in Table 7 without changing the installation position of the lower end. As a result, the pressure loss of the spouted bed was 1.3 kPa, and the average deviation of pressure fluctuation was 0.40 kPa. The gas flow rate in the annular particle layer was calculated to be 0.152 m / s, which was 0.76 times the minimum fluidization speed.

<Examples 8b to 11b>
Instead of setting the gas superficial velocity U to 0.46 m / s, Examples 8b to 11b were carried out under the same conditions as in Examples 8a to 11a, respectively, except that the gas superficial velocity U was set to 0.59 m / s. Table 8 shows the results.

<Examples 8c to 11c>
Instead of setting the gas superficial velocity U to 0.46 m / s, Examples 8c to 11c were carried out under the same conditions as in Examples 8a to 11a, respectively, except that the gas superficial velocity U was set to 0.34 m / s. Table 9 shows the results.

  10A, 10B, 10C, 10D ... Olefin polymerization reactor, 12, 12A ... cylinder (cylindrical part), 20 ... baffle plate (first conical baffle), 23 ... second conical baffle, 25 ... reaction zone, 30 ... Cylindrical baffle (reduced diameter portion), L31 ... particle extraction pipe (transfer means), 32 ... ejector (transfer means), L33 ... particle supply pipe (transfer means), 35a, 35b ... downcomer pipe (transfer means), L38 ... Gas supply pipe, 80 ... Open / close valve, 100A, 100B, 100C ... Polyolefin production system, T1, T2 ... Draft tube, T2a ... Straight pipe portion of the draft tube, T2b ... Diameter expansion portion of the draft tube.

Claims (20)

A cylindrical portion extending vertically;
A reduced diameter portion formed in the cylindrical portion and having a gas introduction opening at the lower end as the inner diameter decreases toward the bottom,
A draft tube provided in the cylindrical portion and extending upward from a position separated from the gas introduction opening;
With
A spouted olefin polymerization reaction apparatus in which a spouted layer is formed in a reaction region surrounded by an inner surface of the reduced diameter portion and an inner surface of the cylindrical portion above the reduced diameter portion.   The draft tube has a straight pipe portion extending downward from the upper end opening with a constant diameter, and a diameter-expanding portion whose diameter increases toward the lower side from the edge of the straight pipe portion, and the diameter-expanding portion is used for introducing the gas. The olefin polymerization reactor according to claim 1, which extends to a position separated from the opening.   In the reaction region, a first cone is disposed above the upper end opening of the draft tube, the outer diameter increases toward the lower side, the upper end is closed, and the lower end is spaced from the inner wall of the cylindrical portion. The olefin polymerization reaction apparatus according to claim 1, further comprising a baffle. 4. The apparatus according to claim 1, comprising a plurality of the reaction regions, wherein polyolefin particles sequentially pass through the plurality of reaction regions from the reaction region on the upstream side to the reaction region on the downstream side . Olefin polymerization reactor. The olefin polymerization reaction apparatus according to claim 4 , further comprising transfer means for transferring polyolefin particles from the reaction region on the upstream side to the reaction region on the downstream side. Before SL transfer means, supplied from the reaction zone of the upstream and particle extraction pipe for extracting the polyolefin particles, an ejector provided in the particle discharge pipe, the polyolefin particles from the ejector to the reaction zone of the downstream The olefin polymerization reaction apparatus according to claim 5 , wherein the olefin polymerization reaction apparatus has a particle supply pipe. Said plurality of reaction areas are formed to be aligned in the vertical direction, the polyolefin particles successively passes from the reaction zone of the upstream located above to the reaction zone downstream located below, claim 4 The olefin polymerization reaction apparatus according to any one of -6 . Said plurality of reaction areas are formed to be aligned in the vertical direction, the polyolefin particles successively passes from the reaction zone of the upstream positioned below into the reaction zone downstream located above, claim 6 The olefin polymerization reaction apparatus described in 1.   The olefin polymerization reaction apparatus according to any one of claims 1 to 8, further comprising a tubular portion extending downward from an edge of the gas introduction opening of the reduced diameter portion.   The olefin polymerization reaction apparatus according to claim 9, wherein the tubular portion further includes a partition that horizontally partitions the inside of the pipe.   An annulus that further includes a cylindrical member that is closed at least at one end and is disposed inside the tubular portion, and a pipe line leading to the gas introduction opening is formed by the outer surface of the cylindrical member and the inner surface of the tubular portion. The olefin polymerization reaction apparatus according to claim 9, having a portion.   A closing plate for closing the lower end of the tubular portion, a gas introduction pipe provided so as to penetrate the closing plate with a narrower pipe line than the pipe line of the tubular portion, and an outer diameter increasing toward the lower side And a second conical baffle whose upper end is closed and whose lower end is spaced from the inner surface of the tubular portion, and the second conical baffle is disposed immediately above the upper end of the gas introduction pipe. The olefin polymerization reaction apparatus according to claim 11.   The olefin polymerization reaction apparatus according to claim 12, wherein the second conical baffle has a cylindrical portion that extends downward from a peripheral edge portion at a lower end of the second conical baffle.   The olefin polymerization reaction apparatus according to any one of claims 1 to 13, further comprising a pipe that communicates with the inside of the draft tube and supplies gas or liquid into the draft tube.   The polyolefin manufacturing method which superposes | polymerizes an olefin by forming the spout layer by a polyolefin particle in the said reaction area | region using the olefin polymerization reaction apparatus as described in any one of Claims 1-14.   A polyolefin production method for polymerizing an olefin by forming a spouted layer of polyolefin particles in the reaction region using the olefin polymerization reaction apparatus according to claim 14, wherein gas and / or in the draft tube through the pipe A polyolefin production method in which the composition of gases existing inside and outside the draft tube in the reaction region is made different from each other by supplying a liquid. Continuously supplying olefin to the olefin polymerization reactor, continuously extracting gas containing unreacted olefin from the olefin polymerization reactor, and returning the extracted gas to the olefin polymerization reactor;
Cooling all or part of the extracted gas to obtain a condensate containing olefin;
The polyolefin manufacturing method of Claim 15 or 16 provided with these.   The method for producing polyolefin according to claim 17, further comprising a step of supplying the condensate to a spout portion of a spout bed formed in the reaction region. An olefin prereactor for polymerizing olefins in the presence of an olefin polymerization catalyst to form polyolefin particles;
The olefin polymerization reaction apparatus according to any one of claims 1 to 14, which is connected to a subsequent stage of the olefin pre-reaction apparatus,
A polyolefin production system comprising:   A polyolefin production method for performing multi-stage polymerization of olefins using the polyolefin production system according to claim 19.

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