High speed and direct driven rotating equipment for polyolefin manufacturing

Abstract

An apparatus and method for melting polymer is provided. In at least one embodiment, the apparatus includes a housing, two or more rotatable members at least partially contained within the housing, where each rotatable member having a shaft coupled thereto. The apparatus also includes a motor having a drive shaft directly coupled to the shaft of the rotatable members such that the rotatable members rotate at a speed of the motor drive shaft. The rotatable members are preferably non-intermeshing and counter-rotating.

1 . An apparatus for melting polymer, comprising: 
 a housing;    two or more rotatable members at least partially contained within the housing, each rotatable member having a shaft coupled thereto; and    a motor having a drive shaft directly coupled to the shaft of at least one of the rotatable members such that the coupled rotatable member rotates at a speed of the motor drive shaft,    wherein the rotatable members are non-intermeshing and counter-rotating.    
   
   
       2 . The apparatus of  claim 1 , wherein the motor is a variable speed motor.  
   
   
       3 . The apparatus of  claim 1 , wherein the motor drive shaft rotates at a rate of about 200 rpm to about 3600 rpm.  
   
   
       4 . The apparatus of  claim 1 , wherein each shaft of the two or more rotatable members are directly coupled to the drive shaft of the motor.  
   
   
       5 . An apparatus for transferring molten polymer, comprising: 
 a first housing having two or more non-intermeshing screws contained therein;    a first motor directly coupled to at least one of the two or more screws and adapted to counter-rotate the screws;    a second housing in fluid communication with the first housing, the second housing having two or more gears contained therein; and    a second motor directly coupled to at least one of the two or more gears and adapted to rotate the two or more rotatable gears.    
   
   
       6 . The apparatus of  claim 5 , wherein the motor is a variable speed motor.  
   
   
       7 . The apparatus of  claim 6 , wherein the motor drive shaft rotates at a rate of about 200 rpm to about 3600 rpm.  
   
   
       8 . A method for polyolefin production, comprising: 
 directing a polyolefin through a continuous mixer to provide a molten polymer, the continuous mixer comprising:    a housing having two or more non-intermeshing screws contained therein; and    a motor directly coupled to the two one or more screws and adapted to counter-rotate the two or more screws at a rate of about 600 rpm or more;    adding one or more additives to the molten polymer within the first housing;    mixing the molten polymer and the one or more additives to provide a mixed polymer comprising the one or more additives at least partially dispersed therein;    directing the mixed polymer to a gear pump comprising:    a housing having two or more gears contained therein; and    a motor directly coupled to at least one of the two or more gears and adapted to rotate the two or more gears at a rate of about 10 rpm to about 1200 rpm; and    pressurizing the mixed polymer within the gear pump to transfer the mixed polymer for further processing.    
   
   
       9 . The method of  claim 8 , wherein the polymer melt advances through the housing at a residence time of about 5 seconds to about 15 seconds.  
   
   
       10 . The method of  claim 8 , wherein the molten polymer is mixed at a variable speed.  
   
   
       11 . The apparatus of  claim 8 , wherein the motor drive shaft rotates at a rate of about 200 rpm to about 3600 rpm.  
   
   
       12 . A method for polyolefin production, comprising: 
 providing polyolefin particles to a twin screw continuous mixer, the twin screw continuous mixer comprising a housing having two or more non-intermeshing rotatable members contained therein, each rotatable member having a shaft coupled thereto, and a motor having a drive shaft directly coupled to the shaft of at least one of the two or more rotatable members;    counter-rotating the two or more rotatable members at a speed of the motor drive shaft without gear reduction;    melting the polymer particles within the housing to provide a polymer melt; and    advancing the polymer melt through the housing.    
   
   
       13 . The method of  claim 12 , wherein the polymer melt advances through the housing at a residence time of about 5 seconds to about 15 seconds.  
   
   
       14 . The method of  claim 13 , wherein the molten polymer is mixed at a variable speed.  
   
   
       15 . The apparatus of  claim 14 , wherein the motor drive shaft rotates at a rate of about 200 rpm to about 3600 rpm.