JP2010202700A - Vapor phase polymerization apparatus, method for manufacturing polymer, and clogging detection method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vapor phase polymerization apparatus capable of detecting whether clogging is generated in a transfer pipe. <P>SOLUTION: The vapor phase polymerization apparatus comprises a vapor phase polymerization tank 1 for vapor phase-polymerizing an olefin, a hopper 2 for storing a polymer of the olefin vapor phase-polymerized in the vapor phase polymerization tank 1, the transfer pipe 3 for connecting the vapor phase polymerization tank 1 and the hopper 2, and a thermometer 4 for measuring a temperature of the transfer pipe 3. Therefore, clogging generated in the transfer pipe 3 can be detected. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a gas phase polymerization apparatus that detects clogging in a transfer pipe in a gas phase polymerization apparatus such as olefin, a method for producing a polymer, and a clogging detection method.

  In the olefin polymerization method using a fluidized bed reactor, a mass of olefin polymer or a lump such as a plate may be generated in the fluidized bed reactor. When the particles are extracted, the lump is extracted and clogs the piping. For this reason, polymerization termination may occur due to defective product extraction, the balance between heat generation and heat removal due to polymerization may be lost, polymerization temperature may be poorly controlled, and polymerization may be terminated.

  As a method for detecting abnormalities in a gas phase polymerization tank such as the generation of a lump, for example, Patent Documents 1 and 2 describe a method of measuring the temperature distribution on the outer shell surface of a fluidized bed type polymerization apparatus with a temperature measuring device. Has been.

JP 11-189603 A (released July 13, 1999) JP 11-193302 A (released July 21, 1999)

  However, in a gas phase polymerization reactor such as a fluidized bed type, a transfer pipe is formed by a polymer mass generated in a transfer pipe that is transferred from the reactor to a downstream gas phase polymerization tank or a hopper after the raw material is polymerized. There is a need to prevent clogging of the transfer pipe because it may be clogged and polymerization may stop.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a gas phase polymerization apparatus capable of detecting whether or not a clogging has occurred in a transfer pipe.

  In order to solve the above problems, a gas phase polymerization apparatus according to the present invention includes a gas phase polymerization tank for vapor phase polymerization of olefin, a container for containing the polymer of the olefin, the gas phase polymerization tank and the container. And a temperature measuring means for measuring the temperature of the transfer tube.

  In the gas phase polymerization apparatus according to the present invention, the temperature measuring means is preferably means for measuring the temperature of the outer wall surface of the transfer pipe.

  In the gas phase polymerization apparatus according to the present invention, the transfer pipe measures a supply port for supplying a gas for cleaning the inside of the transfer pipe into the transfer pipe by the gas phase polymerization tank and the temperature measuring means. It is preferable to provide between the positions.

  In order to solve the above problems, a method for producing a polymer according to the present invention is a method for producing an olefin polymer using a gas phase polymerization apparatus according to the present invention, wherein the olefin is vapor-phase polymerized. A polymerization step and a transfer step of transferring the polymerized olefin polymer to the container via the transfer tube and measuring the temperature of the transfer tube are included.

  Further, in the method for producing a polymer according to the present invention, the transfer pipe measures a supply port for supplying a gas for cleaning the transfer pipe into the transfer pipe by the gas phase polymerization tank and the temperature measuring means. In the transfer step, the gas having a temperature lower than the polymerization temperature in the gas phase polymerization step is preferably supplied from the supply port to the transfer pipe.

  Furthermore, in the method for producing a polymer according to the present invention, the gas is preferably ethylene, hydrogen, nitrogen, or an unreacted source gas in the gas phase polymerization tank.

  In the method for producing a polymer according to the present invention, in the transfer step, the polymer is preferably transferred by a pressure difference inside the gas phase polymerization tank and the container.

  In order to solve the above problems, a blockage detection method according to the present invention is a method for detecting blockage in the transfer pipe in the gas phase polymerization apparatus according to the present invention, wherein the polymer is removed via the transfer pipe. Whether or not the transfer pipe is clogged is detected based on whether or not the temperature of the transfer pipe measured using the temperature measuring unit is lower than a preset temperature.

  According to the present invention, it is possible to detect whether or not a blockage has occurred in the transfer pipe.

It is a mimetic diagram showing a schematic structure of gas phase polymerization device 100 concerning one embodiment of the present invention. It is a figure which shows the structure of the transfer pipe 3 of the gas phase polymerization apparatus 100 which concerns on one Embodiment of this invention.

  An embodiment of the present invention will be described with reference to FIGS.

(Configuration of gas phase polymerization apparatus 100)
First, the configuration of a gas phase polymerization apparatus 100 according to the present embodiment will be described with reference to FIG. FIG. 1 is a schematic diagram showing a schematic configuration of a gas phase polymerization apparatus 100 according to the present embodiment.

  As shown in FIG. 1, the gas phase polymerization apparatus 100 includes a gas phase polymerization tank 1, a hopper (container) 2, a transfer pipe 3, and a thermometer (temperature measuring means) 4.

  The gas phase polymerization apparatus 100 is an apparatus for producing an olefin polymer, and measures the temperature of the transfer pipe 3 when transferring the polymer from the gas phase polymerization tank 1 to the downstream hopper 2 via the transfer pipe 3. A thermometer 4 is provided.

  That is, in the gas phase polymerization apparatus 100, first, the raw material olefin is charged into the gas phase polymerization tank 1 to perform gas phase polymerization. Next, the olefin polymer produced by the polymerization reaction is withdrawn from the gas phase polymerization tank 1 and transferred to the hopper 2 through the transfer pipe 3. At this time, according to the gas phase polymerization apparatus 100 according to the present embodiment, since the temperature of the transfer pipe 3 is measured by the thermometer 4, it is possible to detect whether or not the transfer pipe 3 is clogged. it can. Details of the method for detecting the presence or absence of blockage will be described later.

  Here, the blockage means a state in which the inside of the transfer tube 3 is blocked by a lump or the like. In the present embodiment, the lump is intended to be a lump produced by solidification and solidification of the olefin polymer.

  Examples of the olefin include ethylene, propylene, 1-butene, 1-hexene, 4-methyl-1-pentene and 1-octene. Moreover, an olefin may be used independently and may be used in combination of 2 or more type.

  Examples of combinations of olefins include, for example, ethylene and propylene, ethylene and 1-butene, ethylene and 1-hexene, ethylene and 4-methyl-1-pentene, ethylene and 1-octene, propylene and 1-butene, and ethylene. Examples thereof include 1-butene and 1-hexene, ethylene, 1-butene and 4-methyl-1-pentene, and a copolymer can be formed by this combination. Among them, the olefin copolymer is particularly preferably a copolymer of ethylene and an α-olefin having 3 to 20 carbon atoms, and ethylene having a polyethylene crystal structure and α having 3 to 20 carbon atoms. -More preferred are copolymers with olefins.

  The α-olefin is more preferably an α-olefin having 3 to 8 carbon atoms, and examples thereof include 1-butene, 1-hexene, 4-methyl-1-pentene, and 1-octene.

  Here, the polymerization includes homopolymerization and copolymerization, and the polymer is intended to include a homopolymer and a copolymer.

  The gas phase polymerization tank 1 is a tank for vapor phase polymerization of olefins. Examples of the gas phase polymerization tank 1 include, for example, JP-A-58-201802, JP-A-59-126406, JP-A-2-233708, JP-A-4-234409, JP-A-7-62009. What is necessary is just to use the well-known gaseous-phase fluidized bed type | formula reactor described in gazettes.

  As the configuration of the gas phase polymerization tank 1, as shown in FIG. 1, for example, a gas introduction port 15 for introducing a gas such as an olefin or a catalyst or a circulating gas, a gas dispersion plate 13 for dispersing the introduced gas, and polymerization are performed. You may provide the extraction port 14 which extracts the polymer of an olefin, the gas discharge port 16 which discharges | emits the gas which was not reacting to superposition | polymerization, and the gas circulation line 10 which circulates the discharged | emitted gas.

  The hopper 2 is a container for containing an olefin polymer produced by gas phase polymerization. That is, the olefin polymer polymerized in the gas phase polymerization tank 1 is introduced through the transfer pipe 3. As shown in FIG. 1, the hopper 2 may be a hopper that temporarily stores the introduced polymer. For example, in the case of a gas phase polymerization apparatus that continuously performs gas phase polymerization, a gas phase is used instead of the hopper 2. A polymerization tank may be used.

  The transfer pipe 3 connects the gas phase polymerization tank 1 and the hopper 2, and transfers the olefin polymer generated by the gas phase polymerization in the gas phase polymerization tank 1 to the hopper 2. That is, the transfer pipe 3 transfers the polymer extracted from the extraction port 14 of the gas phase polymerization tank 1 and introduces it from the receiving port 21 provided in the downstream hopper 2. For example, the number of transfer pipes 3 may be three as shown in the present embodiment, but may be one or more.

  In the present embodiment, the transfer pipe 3 is a gas for cleaning the inside of the transfer pipe 3 (hereinafter, a gas for cleaning the inside of the transfer pipe included in the gas phase polymerization apparatus according to the present invention is referred to as “cleaning gas”). It is preferable to provide a supply port to be supplied into the transfer pipe 3 between the gas phase polymerization tank 1 and the position measured by the thermometer 4. According to this, it is possible to more quickly detect whether or not the transfer pipe 3 is clogged, and a polymer mass generated in the transfer pipe 3 by the cleaning gas supplied from the supply port. Can be removed.

  The thermometer 4 measures the temperature of the transfer pipe 3 when the polymer is being transferred. In this embodiment, it is preferable that the thermometer 4 measures the temperature of the outer wall surface of the transfer pipe 3. According to this, by measuring the temperature of the outer wall surface of the transfer pipe 3, it is possible to detect whether or not the transfer pipe 3 is clogged. Examples of the thermometer 4 include a thermocouple thermometer, a radiation thermometer, and a resistance thermometer. Here, the transfer pipe 3 and the thermometer 4 of the present embodiment will be described in detail with reference to FIG.

(Transfer tube 3 and thermometer 4)
FIG. 2 is a diagram showing a configuration of the transfer pipe 3 of the gas phase polymerization apparatus 100 according to the present embodiment. As described above, the gas phase polymerization apparatus 100 includes the thermometer 4 for measuring the temperature of the transfer pipe 3, particularly the outer wall surface of the transfer pipe 3. According to this, it is possible to detect whether or not the transfer pipe 3 is blocked.

  For example, when the polymer produced in the gas phase polymerization tank 1 is extracted and sent to the hopper 2 through the transfer pipe 3, the temperature of the transfer pipe 3 is set to the vapor phase polymerization tank unless the inside of the transfer pipe 3 is clogged. 1 is close to the polymerization temperature.

  On the other hand, for example, if the polymer is agglomerated in the transfer tube 3 to form a lump, the inside of the transfer tube 3 is blocked and the polymer does not flow. As a result, since the polymer does not flow downstream from the position where the blockage occurs, the temperature of the transfer pipe 3 near the position is significantly lower than the polymerization temperature.

  According to the gas phase polymerization apparatus 100 according to the present embodiment, since the thermometer 4 that measures the temperature of the outer wall surface of the transfer pipe 3 is provided, the temperature of the transfer pipe 3 measured by the thermometer 4 is set in advance. Whether or not the transfer pipe 3 is clogged can be detected based on whether or not the temperature is lower than the temperature.

  Here, the preset temperature is intended to be a temperature set to determine whether or not the transfer pipe 3 is clogged. For example, if an olefin polymer is produced several times in advance using the gas phase polymerization apparatus 100, the temperature at which clogging occurs in the transfer pipe 3 at that time is specified, and the average value is set as the temperature. Good.

  Therefore, if the temperature of the transfer pipe 3 is lower than a preset temperature, it can be determined that there is a lump in the transfer pipe 3 and a blockage has occurred. Thereby, the operation of the gas phase polymerization apparatus 100 can be continued without stopping the polymerization reaction by exchanging or cleaning the transfer pipe 3 in which the blockage has occurred.

  The thermometer 4 may be installed directly on the outer wall surface of the transfer pipe 3, for example, or may be measured remotely by attaching a sensor or the like to the outer wall surface of the transfer pipe 3. Moreover, the location measured with the thermometer 4 should just be one location, for example, and may be multiple.

  The position to be measured by the thermometer 4 may be appropriately set depending on the length of the transfer pipe or the like. For example, when the length of the transfer pipe is 5 to 50 m, it is 0 from the outlet 14 of the gas phase polymerization tank 1. It is preferably located within a range 0.5 m before the receiving port 21 of the hopper 2 (range indicated by A in FIG. 2), more preferably 2 m from the outlet 14. If it measures at this position, since the temperature of the transfer pipe 3 in the position where obstruction | occlusion tends to occur can be measured, obstruction | occlusion is easy to detect.

  In addition, as described above, the supply port 31 for supplying a cleaning gas for cleaning the inside of the transfer tube 3 is provided between the gas phase polymerization tank 1 and the position measured by the thermometer 4. It is preferable to provide.

  For example, when the cleaning gas is supplied from the supply port 31 to the transfer pipe 3, the cleaning gas flows downstream from the supply port 31. At this time, a cleaning gas having a temperature lower than the polymerization temperature in the gas phase polymerization tank 1 is supplied from the supply port 31. Therefore, when the clogging in the transfer pipe 3 occurs on the gas phase polymerization tank 1 side than the supply port 31, the inside of the transfer pipe 3 measured by the thermometer 4 is almost occupied by the supplied cleaning gas. . Therefore, the measured value of the thermometer 4 shows a value lower than the polymerization temperature, and it is possible to more clearly detect that the transfer pipe 3 is clogged.

  On the other hand, when the blockage in the transfer pipe 3 occurs on the hopper 2 side with respect to the supply port 31, the polymer staying in the transfer pipe 3 can be discharged by the pressure of the cleaning gas.

  As the cleaning gas, for example, ethylene, hydrogen, nitrogen, or an unreacted raw material gas in the gas phase polymerization tank 1 is preferable. If these gases are used as the cleaning gas, for example, when the hopper 2 is a gas phase polymerization tank in the next step, the cleaning gas can be used in the gas phase polymerization in the next step. Moreover, although the temperature of cleaning gas should just be lower than the polymerization temperature in the gaseous-phase polymerization tank 1, it is preferable that it is -10-50 degreeC, for example. Next, a method for producing a polymer using the gas phase polymerization apparatus 100 according to this embodiment will be described.

(Method for producing polymer)
The method for producing a polymer according to the present embodiment may mainly include a gas phase polymerization step and a transfer step.

  The gas phase polymerization step is a step for vapor phase polymerization of olefin.

  The transfer step is a step of transferring the polymerized olefin polymer to the hopper 2 through the transfer tube 3 and measuring the temperature of the transfer tube 3.

  According to the method for producing a polymer according to the present embodiment, first, a raw material olefin is introduced into the gas phase polymerization tank 1 and subjected to gas phase polymerization to produce a polymer. Next, the produced polymer is extracted from the extraction port 14 to the transfer pipe 3 and transferred to the hopper 2. Here, as described above, the gas phase polymerization apparatus 100 is provided with the thermometer 4 for measuring the temperature of the transfer pipe 3, and the temperature of the transfer pipe 3 for transferring the polymer is measured by the thermometer 4. Thereby, it is detected whether or not the transfer tube 3 is blocked by whether or not the temperature of the transfer tube 3 measured using the thermometer 4 is lower than a preset temperature.

  Here, a series of flows for producing a polymer using the gas phase polymerization apparatus 100 according to the present embodiment will be described. The gas phase polymerization in the gas phase polymerization tank 1 shown below is only an example, and a polymer may be generated using, for example, a conventionally known gas phase polymerization method.

  In the polymer production method according to the present embodiment, first, the temperature and pressure in the gas phase polymerization tank 1 are set according to the polymerization conditions described later. Next, the main raw material olefin gas and hydrogen are introduced from the circulation gas line 10 and the catalyst is also introduced. The introduced olefin gas or the like rises and undergoes a polymerization reaction while forming a fluidized bed. Thereafter, the olefin polymer produced by the polymerization reaction is extracted from an extraction port 14 provided below the gas phase polymerization tank 1.

  Here, the flow rate of the olefin gas that has not reacted to the polymerization that has passed through the fluidized bed (hereinafter referred to as unreacted gas) is reduced in the deceleration region located in the upper part of the gas phase polymerization tank 1. The unreacted gas is discharged from the gas discharge port 16 provided at the upper part of the gas phase polymerization tank 1 to the circulation gas line 10 and is provided below the gas dispersion plate 13 of the gas phase polymerization tank 1 through the circulation gas line 10. The gas is transferred to the gas inlet 15.

  At this time, before introducing the unreacted gas into the gas phase polymerization tank 1, it is necessary to lower the polymerization reaction heat possessed by the gas. Therefore, the unreacted gas is cooled by the heat exchanger 12 provided in the circulation gas line 10, compressed by the compressor 11, and then introduced from the gas inlet 15. Thus, the unreacted gas introduced into the gas phase polymerization tank 1 can be used again for the polymerization reaction.

  Next, the polymer extracted from the extraction port 14 is transferred to the hopper 2 through the transfer pipe 3. At this time, in the transfer pipe 3, the polymer is preferably transferred by a pressure difference inside the gas phase polymerization tank 1 and the hopper 2. According to this, the polymer can be effectively transferred with simple equipment.

  The polymer may be transferred, for example, continuously or intermittently, but it is more preferable to transfer the polymer continuously. According to this, compared with the case where a polymer is intermittently transferred, it is possible to prevent the polymer from staying in the transfer pipe 3. As such a transfer method, for example, a method described in JP 2001-139605 A, JP 2002-530441 A, or JP 2008-143929 A may be used.

  In the present embodiment, when the polymer is transferred through the transfer pipe 3, a cleaning gas having a temperature lower than the polymerization temperature in the gas phase polymerization tank 1 is supplied from the supply port 31 to the transfer pipe 3. Is preferred. According to this, since the cleaning gas having a temperature lower than the polymerization temperature is supplied from the supply port 31, for example, when the transfer pipe 3 is clogged, the temperature in the transfer pipe 3 is quickly lowered. , Occlusion can be detected.

  The polymerization conditions in the gas phase polymerization reaction may be known polymerization conditions, for example. That is, the pressure in the gas phase polymerization tank 1 may be within a range in which all or at least a part of the olefin can exist as a gas phase, and may be, for example, 0.1 to 5.0 MPa. More preferably, it is 5-3.0 MPa. Moreover, what is necessary is just to select suitably the temperature in the gas phase polymerization tank 1 with the catalyst to be used, the pressure in the gas phase polymerization tank 1, the kind of olefin to superpose | polymerize, etc., for example, 30-110 degreeC may be sufficient. Further, the flow rate of the circulating gas circulating in the gas phase polymerization tank 1 may be, for example, 10 to 100 cm / second, but more preferably 20 to 70 cm / second. Further, hydrogen or an inert gas may coexist in the circulating gas.

  Here, in this specification, the circulation gas is intended to collectively refer to all the gases that are introduced into the gas phase polymerization tank 1 including the olefin gas. That is, in olefin gas phase polymerization, in addition to the olefin gas used as a raw material, hydrogen that serves as a molecular weight regulator or nitrogen accompanying the supply of a catalyst or the like may be included.

  The olefin gas contains alkanes as impurities in the raw material and as a by-product due to a hydrogenation reaction during gas phase polymerization. Therefore, for example, when ethylene, butene, hexene, or the like is used as the olefin gas, ethane, butane, hexane, or the like is present. Thus, the circulating gas contains hydrogen, nitrogen, and alkanes (ethane, butane, hexane, etc.) in addition to the olefin gas.

  The polymerization catalyst used for polymerizing the olefin may be a known olefin polymerization catalyst such as a Ziegler type catalyst or a Philips type catalyst, but is a metallocene catalyst using a metallocene compound. It is more preferable.

  That is, in terms of quality, generally, when a metallocene-based catalyst is used, the composition distribution is narrow, so that the strength of the produced polymer is increased. In addition, the metallocene-based catalyst depends on the cocatalyst, but since the active sites are limited, the molecular weight distribution of the polymer can be controlled, and the above-described composition distribution is narrow, so that the blocking of the film is reduced. . Also, some metallocene catalysts can introduce long chain branching into the polymer, so that processability can be improved.

  Further, regarding the production side (particularly, the gas phase polymerization step), since the metallocene catalyst has good copolymerizability, the comonomer concentration in the gas phase is low, so that the amount of comonomer adsorbed on the product powder is reduced. Accordingly, the amount of comonomer accompanying the post-treatment system is reduced, so that the comonomer loss or recovery time is reduced.

As a method for producing a Ziegler type catalyst, for example, JP 59-8706, JP 59-22907, JP 59-22908, JP 59-64611, JP 59-71309, JP-A-60-42404, JP-A-60-13
No. 3011, JP-A-60-215006, JP-A-62-2232405,
JP-A-62-297304, JP-A-1-256502, JP-A-1-2898
09, JP-A-3-81303, JP-A-3-88808, JP-A-3-9
No. 3803, JP-B 56-18132, JP-B 56-15807, JP-B 61-50964, JP-B 61-363, JP-B 62-56885, JP-A 11-322833. A known manufacturing method described in Japanese Patent Laid-Open No. 2002-187909 may be used. In addition, particles obtained by polymerizing a small amount of olefin can be used as necessary (see, for example, JP-A-2001-342211). Such pretreatment for polymerizing a small amount of olefin may be referred to as prepolymerization.

  Examples of the metallocene catalyst include a solid catalyst component (for example, JP-A-61-108610) in which a promoter component such as an organoaluminum compound, an organoaluminum oxy compound, and a boron compound and a metallocene compound are supported on a particulate carrier. Prepolymerization using a solid catalyst component described in JP-A No. 61-296008, JP-A 63-89505, JP-A 3-234709, JP-A 6-336502, etc. The particles obtained in this way can be used. Moreover, you may use together promoter components, such as an organoaluminum compound and a boron compound, as needed.

  In addition, for example, a solid catalyst component (for example, see JP-A-2003-171212) obtained by supporting a promoter component such as an organoaluminum compound, an organoaluminum oxy compound, a boron compound, and an organozinc compound on a particulate carrier. The particles obtained by prepolymerizing a small amount of olefin in combination with a catalyst component such as a metallocene compound or an organoaluminum compound may be used as the metallocene catalyst.

  EXAMPLES Hereinafter, although this invention is demonstrated based on an Example, this invention is not limited to this Example. In the examples shown below, the measured values of each item were measured by the following method.

(1) Density (Unit: kg / m ³ )
It measured according to the method prescribed | regulated to A method among JISK7112-1980. The sample was annealed according to JIS K6760-1995.

(2) Melt flow rate (MFR, unit: g / 10 minutes)
According to the method defined in JIS K7210-1995, the measurement was performed under the conditions of a load of 21.18 N and a temperature of 190 ° C.

[Example 1]
In Example 1, a fluidized bed gas phase polymerization reactor (gas phase polymerization tank) and a post-treatment system hopper (container) for recovering a polymer from the reactor are connected by two transfer pipes. A polymerization apparatus was produced. One transfer pipe continuously transferred the polymer, and the other transfer pipe intermittently transferred the polymer.

  Of these transfer pipes, a thermometer (temperature measuring means) is installed on the outer wall surface of the transfer pipe that continuously transfers the polymer at a position 2 m from the transfer start position (extraction port). Monitored. Further, a cleaning gas supply port was provided at a position 0.45 m from the transfer start position of the transfer pipe.

  The polymerization reaction conditions were a polymerization temperature: 87 ° C., a pressure: 2.0 MPaG, and a circulating gas flow rate: 55 cm / second. The gas composition was 57.1 mol% ethylene, 9.4 mol% hydrogen, 19.6 mol% 1-butene, 12.0 mol% nitrogen, and 1.9 mol% hexane.

Further, a catalyst and triethylaluminum were added during the polymerization reaction. As the catalyst, a prepolymerized catalyst equivalent to the prepolymerized catalyst described in Example 2 of JP-A-2001-342211 was used. Triethylaluminum was supplied at 5.5 mol / t to the polymer produced. Furthermore, 25 degreeC ethylene was supplied at 50 kg / h from the supply port of the cleaning gas described above. Under such conditions, ethylene and 1-butene were copolymerized. The apparatus was operated at an ethylene-1-butene copolymer density of 921.1 kg / m ³ and MFR of 1.11 g / 10 minutes.

  While the apparatus was in operation, the thermometer installed in the transfer pipe showed about 74 ° C., but the temperature dropped rapidly on the way to 28 ° C. Therefore, the transfer pipe was replaced with a spare transfer pipe.

  As a result, it was possible to continue the operation without causing any abnormality in the polymerization temperature in the gas phase polymerization reactor. When the transfer pipe whose temperature was lowered was opened and inspected, the polymer was agglomerated and it was confirmed that the transfer pipe was blocked.

[Comparative Example 1]
In Comparative Example 1, an apparatus was produced with the same configuration except that the thermometer and the cleaning gas supply port in the gas phase polymerization apparatus produced in Example 1 were not provided.

The polymerization reaction conditions were a polymerization temperature: 87 ° C., a pressure: 2.0 MPaG, and a circulating gas flow rate: 55 cm / second. The gas composition was 54.3 mol% ethylene, 10.0 mol% hydrogen, 20.8 mol% 1-butene, 12.8 mol% nitrogen, and 2.1 mol% hexane. The same catalyst and triethylaluminum as in Example 1 were used. The apparatus was operated at an ethylene-1-butene copolymer density of 920.7 kg / m ³ and MFR of 1.16 g / 10 min.

  Since the polymerization temperature in the gas phase polymerization reactor suddenly started to rise during the operation of the apparatus, heat removal was enhanced by a heat exchanger. However, since the polymerization temperature could not be controlled and the polymerization temperature reached 95 ° C., an emergency quencher was added to stop the polymerization. As a result of opening inspection, blockage was confirmed in the transfer pipe.

  The present invention is not limited to the configurations described above, and various modifications are possible within the scope of the claims, and technical means disclosed in different embodiments and examples, respectively. Embodiments and examples obtained by combining these are also included in the technical scope of the present invention.

  The gas phase polymerization apparatus according to the present invention can be applied to the production of polyolefins such as polypropylene and polyethylene.

1 Gas phase polymerization tank 2 Hopper (container)
3 Transfer pipe 4 Thermometer (temperature measuring means)

Claims (8)

A gas phase polymerization tank for gas phase polymerization of olefin;
A container for containing the olefin polymer gas-phase polymerized in the gas-phase polymerization tank;
A transfer pipe connecting the gas phase polymerization tank and the container;
A gas phase polymerization apparatus comprising temperature measuring means for measuring the temperature of the transfer pipe.   The gas phase polymerization apparatus according to claim 1, wherein the temperature measuring means is a means for measuring the temperature of the outer wall surface of the transfer pipe.   The said transfer pipe is provided with the supply port which supplies the gas for wash | cleaning the inside of the said transfer pipe into the said transfer pipe between the position measured by the said vapor phase polymerization tank and the said temperature measurement means, The claim 1 or 2 A gas phase polymerization apparatus as described in 1. above. A method for producing an olefin polymer using the gas phase polymerization apparatus according to any one of claims 1 to 3,
A gas phase polymerization step for gas phase polymerization of olefin;
A method for producing a polymer, comprising: transferring a polymer of the polymerized olefin to the container via the transfer pipe, and measuring a temperature of the transfer pipe. The transfer pipe is provided with a supply port for supplying a gas for cleaning the inside of the transfer pipe into the transfer pipe between the gas phase polymerization tank and a position measured by the temperature measuring means,
5. The method for producing a polymer according to claim 4, wherein, in the transfer step, the gas having a temperature lower than the polymerization temperature in the gas phase polymerization step is supplied from the supply port to the transfer pipe.   The method for producing a polymer according to claim 5, wherein the gas is ethylene, hydrogen, nitrogen, or an unreacted raw material gas in the gas phase polymerization tank.   The method for producing a polymer according to any one of claims 4 to 6, wherein in the transfer step, the polymer is transferred by a pressure difference inside the gas phase polymerization tank and the container. The gas phase polymerization apparatus according to claim 1, wherein the blockage in the transfer pipe is detected.
When the polymer is being transferred through the transfer pipe, the transfer pipe is blocked depending on whether the temperature of the transfer pipe measured using the temperature measuring means is lower than a preset temperature. A blockage detection method that detects whether or not it has occurred.

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