JP2006206629A - Process for producing polyolefin - Google Patents

Process for producing polyolefin Download PDF

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Publication number
JP2006206629A
JP2006206629A JP2005016677A JP2005016677A JP2006206629A JP 2006206629 A JP2006206629 A JP 2006206629A JP 2005016677 A JP2005016677 A JP 2005016677A JP 2005016677 A JP2005016677 A JP 2005016677A JP 2006206629 A JP2006206629 A JP 2006206629A
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gas phase
polymerization tank
powder
phase polymerization
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Arihiro Saito
有弘 斉藤
Yoichi Konno
容一 今野
Jitsuo Kurokawa
実男 黒川
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Sumitomo Chemical Co Ltd
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Sumitomo Chemical Co Ltd
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Abstract

<P>PROBLEM TO BE SOLVED: To provide a process for producing a polyolefin which enables the prevention of blocking up and clogging of withdrawal piping by a polymer powder on withdrawing a polymer powder from a gas phase polymerization tank to a powder separator. <P>SOLUTION: This method for producing a polyolefin uses a polymerization apparatus which has n (provided n is an integer of n≥2) gas phase polymerization tanks arranged in series and a powder separator, the n-th gas phase polymerization tank and the powder separator being connected by piping for withdrawing a polymer powder, and the ratio (Pn-1/Pn) of the pressure [Pn-1 (kPaG)] of the (n-1)-th polymerization tank to the pressure [Pn (kPaG)] of the n-th polymerization tank is 1.2≤Pn-1/Pn≤2.5 and the difference [Pn-Ps (kPaG)] between the pressure ([Pn (kPaG)]) of the n-th polymerization tank and the pressure [Ps (kPaG)] of the powder separator is Pn-Ps (kPaG)≤800 (kPaG). <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

本発明はポリオレフィンの製造方法に関するものである。詳しくは、気相重合槽から重合パウダーをパウダー分離器へ抜出すときに、重合パウダーによる抜出し配管の詰まり、閉塞を防止することができるポリオレフィンの製造方法に関するものである。   The present invention relates to a method for producing a polyolefin. More specifically, the present invention relates to a method for producing a polyolefin capable of preventing clogging and blockage of an extraction pipe by polymerization powder when the polymerization powder is extracted from a gas phase polymerization tank to a powder separator.

ポリオレフィンの製造方法において、気相重合槽を用いて得られた重合パウダーは、通常、気相重合槽からパウダー分離器へ抜出され、パウダー分離器によって、未反応のオレフィンモノマーと分離される。   In the polyolefin production method, the polymer powder obtained using the gas phase polymerization tank is usually extracted from the gas phase polymerization tank to the powder separator and separated from the unreacted olefin monomer by the powder separator.

例えば、米国特許第4,340,701号公報には、未反応のオレフィンモノマーを除去する方法として、不活性雰囲気下で、ポリマーの温度が少なくとも90℃に上昇するまで、機械的手段によって、粒子状のオレフィンポリマーを撹拌し、前記オレフィンポリマーが冷却する前に、放出されたオレフィンモノマーを分離する方法が記載されている。   For example, US Pat. No. 4,340,701 describes a method for removing unreacted olefin monomers by mechanical means until the polymer temperature rises to at least 90 ° C. under an inert atmosphere. A process is described in which the shaped olefin polymer is stirred and the released olefin monomer is separated before the olefin polymer cools.

また、米国特許第6,335,402号公報には、気相重合において、固体が流動する気相重合反応器や装置部品の内部に生成する付着物を抑制する方法として、ポリオレフィンと静電気防止剤からなり、厚さが0.1〜800μmである静電気防止層がコートされた気相重合反応器や装置部品が記載されている。   US Pat. No. 6,335,402 also discloses a polyolefin and an antistatic agent as a method for suppressing deposits generated inside a gas phase polymerization reactor or apparatus component in which a solid flows in gas phase polymerization. A gas phase polymerization reactor and apparatus parts coated with an antistatic layer having a thickness of 0.1 to 800 μm are described.

米国特許第4,340,701号公報U.S. Pat. No. 4,340,701 米国特許第6,335,402号公報US Pat. No. 6,335,402

しかし、上記の公報等の方法においても、重合パウダーを抜出す気相重合槽の圧力とパウダー分離器の圧力の差が大きい場合、重合パウダーの表面に未反応のオレフィンモノマーが析出し、重合パウダーの表面が粘着性を有することがあり、気相重合槽から重合パウダーをパウダー分離器へ抜出すときに、重合パウダーによる抜出し配管の詰まり、閉塞を起こすことがあった。
かかる状況において、本発明の目的は、気相重合槽から重合パウダーをパウダー分離器へ抜出すときに、重合パウダーによる抜出し配管の詰まり、閉塞を防止することができるポリオレフィンの製造方法を提供することにある。
However, even in the method described in the above publication, when the difference between the pressure of the gas phase polymerization tank for extracting the polymer powder and the pressure of the powder separator is large, unreacted olefin monomer is deposited on the surface of the polymer powder, and the polymer powder When the polymer powder is extracted from the gas phase polymerization tank to the powder separator, the extraction pipe is clogged or clogged with the polymer powder.
In such a situation, an object of the present invention is to provide a method for producing a polyolefin capable of preventing clogging and clogging of an extraction pipe by polymerization powder when the polymerization powder is extracted from a gas phase polymerization tank to a powder separator. It is in.

本発明者等は、検討の結果、本発明が、上記の課題を解決できることを見出し、本発明を完成させるに至った。
すなわち、本発明は、
少なくともn個(ただし、nは、n≧2である整数)の直列に配置された気相重合槽と、パウダー分離器とを有し、第n番目の気相重合槽とパウダー分離器が重合パウダーの抜出し配管によって接続されている重合装置を用いるポリオレフィンの製造方法であって、下記の要件(I)と要件(II)とを満足するポリオレフィンの製造方法に係るものである。
要件(I):
第n−1番目の重合槽の圧力(Pn-1(kPaG))と第n番目の重合槽の圧力(Pn(kPaG))の比(Pn-1/Pn)が、
1.2≦Pn-1/Pn≦2.5
であること
要件(II):
第n番目の重合槽の圧力(Pn(kPaG))とパウダー分離器の圧力(Ps(kPaG))の差(Pn−Ps(kPaG))が、
Pn−Ps(kPaG)≦800(kPaG)
であること
As a result of the study, the present inventors have found that the present invention can solve the above problems, and have completed the present invention.
That is, the present invention
It has at least n (where n is an integer satisfying n ≧ 2) gas phase polymerization tanks arranged in series and a powder separator, and the nth gas phase polymerization tank and the powder separator are polymerized. A polyolefin production method using a polymerization apparatus connected by a powder extraction pipe, which relates to a polyolefin production method satisfying the following requirements (I) and (II).
Requirement (I):
The ratio (Pn-1 / Pn) of the pressure (Pn-1 (kPaG)) of the (n-1) th polymerization tank and the pressure (Pn (kPaG)) of the nth polymerization tank is
1.2 ≦ Pn−1 / Pn ≦ 2.5
Requirement (II):
The difference (Pn−Ps (kPaG)) between the pressure of the n-th polymerization tank (Pn (kPaG)) and the pressure of the powder separator (Ps (kPaG)) is
Pn-Ps (kPaG) ≦ 800 (kPaG)
Be

本発明のポリオレフィンの製造方法によれば、気相重合槽から重合パウダーをパウダー分離器へ抜出すときに、重合パウダーによる抜出し配管の詰まり、閉塞を防止することができる。   According to the method for producing a polyolefin of the present invention, when the polymer powder is extracted from the gas phase polymerization tank to the powder separator, the extraction pipe can be prevented from being clogged or blocked by the polymer powder.

本発明のポリオレフィンの製造方法で用いる重合装置は、少なくともn個(ただし、nは、n≧2である整数)の直列に配置された気相重合槽と、パウダー分離器とを有し、第n番目の気相重合槽とパウダー分離器が重合パウダーの抜出し配管によって接続されている重合装置である。
前記の気相重合槽として用いられる気相重合反応器としては、流動層を有する反応器が挙げられ、例えば、撹拌機を用いずに、気流によって撹拌を行う気相流動層型の反応器や、撹拌機による撹拌と気流による攪拌とを併用する撹拌流動層型の反応器などが挙げられる。
The polymerization apparatus used in the method for producing a polyolefin of the present invention has at least n (where n is an integer satisfying n ≧ 2) gas phase polymerization tanks arranged in series, and a powder separator. This is a polymerization apparatus in which an n-th gas phase polymerization tank and a powder separator are connected by a polymerization powder extraction pipe.
Examples of the gas phase polymerization reactor used as the gas phase polymerization tank include a reactor having a fluidized bed. For example, without using a stirrer, a gas phase fluidized bed type reactor in which stirring is performed by an air flow, An agitated fluidized bed type reactor that uses agitation with a stirrer and agitation with an air current is used.

本発明のポリオレフィンの製造方法は、第n−1番目の重合槽の圧力(Pn-1(kPaG))と第n番目の重合槽の圧力(Pn(kPaG))の比(Pn-1/Pn)を、1.2≦Pn-1/Pn≦2.5(要件(I))とし、
第n番目の気相重合槽からパウダー分離器へ、重合パウダーを抜出すときに、第n番目の重合槽の圧力(Pn(kPaG))とパウダー分離器の圧力(Ps(kPaG))の差(Pn−Ps(kPaG))を、Pn−Ps(kPaG)≦800(kPaG)(要件(II))とする製造方法である。
The method for producing a polyolefin of the present invention is the ratio (Pn-1 / Pn) of the pressure (Pn-1 (kPaG)) of the (n-1) th polymerization tank and the pressure (Pn (kPaG)) of the nth polymerization tank. ) 1.2 ≦ Pn−1 / Pn ≦ 2.5 (requirement (I))
The difference between the pressure of the nth polymerization tank (Pn (kPaG)) and the pressure of the powder separator (Ps (kPaG)) when extracting the polymerization powder from the nth gas phase polymerization tank to the powder separator (Pn-Ps (kPaG)) is a manufacturing method in which Pn-Ps (kPaG) ≦ 800 (kPaG) (requirement (II)).

気相重合槽からパウダー分離器へ、重合パウダーを抜出すときに、気相重合槽の圧力とパウダー分離器の圧力の差が大きいと、重合パウダーの表面に未反応のオレフィンモノマーが析出し、重合パウダーの表面が粘着性を有することがあり、気相重合槽からパウダー分離器への重合パウダーの抜出し配管が詰まることがある。   When the polymerization powder is extracted from the gas phase polymerization tank to the powder separator, if the difference between the pressure of the gas phase polymerization tank and the pressure of the powder separator is large, unreacted olefin monomer is deposited on the surface of the polymerization powder, The surface of the polymer powder may be sticky, and the polymer powder extraction pipe from the gas phase polymerization tank to the powder separator may be clogged.

前記の要件(I)および要件(II)を満足する本発明の製造方法は、抜出し配管の詰まりおよび閉塞を防止することができる。本発明の製造方法は、段階的に圧力を下げる方法であり、段階的に圧力を下げることによって、重合パウダーの表面への未反応のオレフィンモノマーの析出を抑えることができると考えられる。   The production method of the present invention that satisfies the requirements (I) and (II) can prevent clogging and blockage of the extraction pipe. The production method of the present invention is a method of decreasing the pressure stepwise, and it is considered that precipitation of unreacted olefin monomer on the surface of the polymer powder can be suppressed by decreasing the pressure stepwise.

気相重合槽からパウダー分離器へ、重合パウダーを抜出す方法としては、例えば、
(1)気相重合槽からパウダー分離器間の圧力勾配を利用して連続に、抜出す方法、
(2)気相重合槽の出口配管に弁を設けて、一定時間毎に開閉して間欠に、抜出す方法
等が挙げられる。
As a method for extracting the polymer powder from the gas phase polymerization tank to the powder separator, for example,
(1) A method of continuously extracting from a gas phase polymerization tank using a pressure gradient between powder separators,
(2) A method may be mentioned in which a valve is provided at the outlet pipe of the gas phase polymerization tank, and the valve is opened / closed at regular intervals and extracted intermittently.

本発明の方法によって、製造されるポリオレフィンとしては、例えば、プロピレン単独重合体、プロピレン−エチレンブロックコポリマー、プロピレン−エチレンランダムコポリマー、プロピレン−ブテンコポリマー、プロピレン−エチレン−ブテン−ターポリマー、直鎖状低密度ポリエチレン、高密度ポリエチレン等が挙げられる。
本発明の方法は、低融点で粘着性の高いコポリマーやターポリマーの製造に、好ましく用いられる。
Examples of polyolefins produced by the method of the present invention include propylene homopolymers, propylene-ethylene block copolymers, propylene-ethylene random copolymers, propylene-butene copolymers, propylene-ethylene-butene-terpolymers, linear low polymers. A density polyethylene, a high density polyethylene, etc. are mentioned.
The method of the present invention is preferably used for the production of copolymers and terpolymers having a low melting point and high adhesion.

本発明の方法によって、製造されるポリオレフィンに用いられるオレフィンとしては、例えば、炭素数2〜8のオレフィンから選ばれる少なくとも1種のオレフィンが挙げられ、単独重合体に用いられるオレフィンとしては、例えば、エチレン、プロピレン等が挙げられ、共重合体に用いられるオレフィンとしては、例えば、エチレン、プロピレン、1−ブテン、1−ヘキセン、4−メチル−1−ペンテン等が挙げられる。   Examples of the olefin used in the polyolefin produced by the method of the present invention include at least one olefin selected from olefins having 2 to 8 carbon atoms. Examples of the olefin used in the homopolymer include: Examples of the olefin used in the copolymer include ethylene, propylene, 1-butene, 1-hexene, and 4-methyl-1-pentene.

以下に、プロピレン−1−ブテンコポリマーの製造を例として、図1を示して、具体的に説明する。
実施例1
図1に示したとおりの重合装置を用いた。すなわち、
第1気相重合槽(1)と第2気相重合槽(5)の2個の気相重合槽と、パウダー分離器(7)を有し、
第1気相重合槽(1)には、オレフィンモノマー供給配管(2)と触媒供給配管(3)が接続されており、
パウダー分離器(7)には、未反応モノマー移送配管(8)と重合パウダー移送配管(9)が接続され、さらに、
第1気相重合槽(1)と第2気相重合槽(5)が、第1気相重合槽(1)から第2気相重合槽(5)への移送配管(4)で接続され、
第2気相重合槽(5)とパウダー分離器(7)が、第2気相重合槽(5)からパウダー分離器(7)への移送配管(6)で接続された重合装置を用いた。
なお、以下、第1気相重合槽(1)の圧力をP1(kPaG)で表し、第2気相重合槽(5)の圧力をP2(kPaG)で表し、パウダー分離器(7)の圧力をPS(kPaG)で表した。
図1に示した装置を用いて、下記の圧力条件で、プロピレンと1−ブテンを共重合して、1−ブテンの含有量が24重量%であるプロピレン−1−ブテンランダムコポリマーを製造した(ただし、プロピレン−1−ブテンランダムコポリマーの全量を100重量%とした)。
1=1600(kPaG)
2=800(kPaG)
S=100(kPaG)
1/P2=1600/800=2.0
2−PS=800−100=700
第2気相重合槽(5)からパウダー分離器(7)への抜出しに問題はなく、長時間連続運転が可能であった。
Hereinafter, the production of propylene-1-butene copolymer will be described in detail with reference to FIG. 1 as an example.
Example 1
A polymerization apparatus as shown in FIG. 1 was used. That is,
Two gas phase polymerization tanks, a first gas phase polymerization tank (1) and a second gas phase polymerization tank (5), and a powder separator (7);
An olefin monomer supply pipe (2) and a catalyst supply pipe (3) are connected to the first gas phase polymerization tank (1),
An unreacted monomer transfer pipe (8) and a polymerized powder transfer pipe (9) are connected to the powder separator (7).
The first gas phase polymerization tank (1) and the second gas phase polymerization tank (5) are connected by a transfer pipe (4) from the first gas phase polymerization tank (1) to the second gas phase polymerization tank (5). ,
A polymerization apparatus in which the second gas phase polymerization tank (5) and the powder separator (7) were connected by a transfer pipe (6) from the second gas phase polymerization tank (5) to the powder separator (7) was used. .
Hereinafter, the pressure of the first gas phase polymerization tank (1) is represented by P 1 (kPaG), the pressure of the second gas phase polymerization tank (5) is represented by P 2 (kPaG), and the powder separator (7). The pressure was expressed as P S (kPaG).
Using the apparatus shown in FIG. 1, propylene and 1-butene were copolymerized under the following pressure conditions to produce a propylene-1-butene random copolymer having a 1-butene content of 24% by weight ( However, the total amount of the propylene-1-butene random copolymer was 100% by weight).
P 1 = 1600 (kPaG)
P 2 = 800 (kPaG)
P S = 100 (kPaG)
P 1 / P 2 = 1600/800 = 2.0
P 2 −P S = 800−100 = 700
There was no problem in the extraction from the second gas phase polymerization tank (5) to the powder separator (7), and continuous operation for a long time was possible.

比較例
図1に示した装置を用いて、下記の圧力条件で、プロピレンと1−ブテンを共重合して、1−ブテンの含有量が24重量%であるプロピレン−1−ブテンランダムコポリマーを製造した。
1=1600(kPaG)
2=1400(kPaG)
S=100(kPaG)
1/P2=1600/1400=1.1
2−PS=1400−100=1300
第2気相重合槽(5)からパウダー分離器(7)への抜出し配管(6)の内部で、ポリマーの詰まりが発生し、運転が継続できなかった。
Comparative Example Propylene-1-butene random copolymer having a 1-butene content of 24% by weight was produced by copolymerizing propylene and 1-butene under the following pressure conditions using the apparatus shown in FIG. did.
P 1 = 1600 (kPaG)
P 2 = 1400 (kPaG)
P S = 100 (kPaG)
P 1 / P 2 = 1600/1400 = 1.1
P 2 −P S = 1400−100 = 1300
Clogging of the polymer occurred inside the extraction pipe (6) from the second gas phase polymerization tank (5) to the powder separator (7), and the operation could not be continued.

実施例1における気相重合槽が2槽(n=2)である装置のプロセスフローを示す図The figure which shows the process flow of the apparatus whose gas phase polymerization tank in Example 1 is 2 tanks (n = 2).

符号の説明Explanation of symbols

1・・・第1気相重合槽(圧力=P1
2・・・オレフィンモノマー供給配管
3・・・触媒供給配管
4・・・第1気相重合槽からの移送配管
5・・・第2気相重合槽(圧力=P2
6・・・第2気相重合槽からの移送配管
7・・・パウダー分離器(圧力=PS
8・・・未反応モノマー移送配管
9・・・重合パウダー移送配管
1 ... 1st gas phase polymerization tank (pressure = P 1 )
2 ... olefinic monomer feed pipe 3 ... catalyst supply pipe 4 ... transfer pipe from the first gas-phase polymerization vessel 5 ... second gas phase polymerization tank (pressure = P 2)
6 ... Transfer pipe from second gas phase polymerization tank 7 ... Powder separator (pressure = P S )
8 ... Unreacted monomer transfer pipe 9 ... Polymerized powder transfer pipe

Claims (1)

少なくともn個(ただし、nは、n≧2である整数)の直列に配置された気相重合槽と、パウダー分離器とを有し、第n番目の気相重合槽とパウダー分離器が重合パウダーの抜出し配管によって接続されている重合装置を用いるポリオレフィンの製造方法であって、下記の要件(I)と要件(II)とを満足するポリオレフィンの製造方法。
要件(I):
第n−1番目の重合槽の圧力(Pn-1(kPaG))と第n番目の重合槽の圧力(Pn(kPaG))の比(Pn-1/Pn)が、
1.2≦Pn-1/Pn≦2.5
であること
要件(II):
第n番目の重合槽の圧力(Pn(kPaG))とパウダー分離器の圧力(Ps(kPaG))の差(Pn−Ps(kPaG))が、
Pn−Ps(kPaG)≦800(kPaG)
であること
It has at least n (where n is an integer satisfying n ≧ 2) gas phase polymerization tanks arranged in series and a powder separator, and the nth gas phase polymerization tank and the powder separator are polymerized. A polyolefin production method using a polymerization apparatus connected by a powder extraction pipe, wherein the polyolefin production method satisfies the following requirements (I) and (II).
Requirement (I):
The ratio (Pn-1 / Pn) of the pressure (Pn-1 (kPaG)) of the (n-1) th polymerization tank and the pressure (Pn (kPaG)) of the nth polymerization tank is
1.2 ≦ Pn−1 / Pn ≦ 2.5
Requirement (II):
The difference (Pn−Ps (kPaG)) between the pressure of the n-th polymerization tank (Pn (kPaG)) and the pressure of the powder separator (Ps (kPaG)) is
Pn-Ps (kPaG) ≦ 800 (kPaG)
Be
JP2005016677A 2005-01-25 2005-01-25 Process for producing polyolefin Pending JP2006206629A (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2013508484A (en) * 2009-12-02 2013-03-07 ボレアリス アクチエンゲゼルシャフト Method for producing polyolefin

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2013508484A (en) * 2009-12-02 2013-03-07 ボレアリス アクチエンゲゼルシャフト Method for producing polyolefin

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