Optimized agitator system for production of polyolefin

Abstract

The various embodiments of the present invention relate to a polymerization reactor where the agitator mixing performance is optimized for use with a high activity catalyst and methods for developing the same.

1 - 26 . (canceled) 
     
     
         27 . A method for selecting agitator speed to reduce the cost of operating a CSTR comprising:
 a. measuring the HUT/BT and circulation ratio of the reactor,   b. measuring the mixing performance indicator of the final polymer product,   c. plotting the HUT/BT and circulation ratio vs the performance indicator,   d. varying the agitator speed or HUT to get a new HUT/BT and circulation ratio,   e. repeating steps a-d until the plotted line of step c shows a roughly horizontal lines (asymptote), and   f. lowering the agitation rate of the reactor for commercial polyethylene polymerization so the mixing performance falls within a “Zone II” or “Zone III” region on each plot from step c,   g. operate the CSTR reactor using the identified agitation speed.   
     
     
         28 . A method for selecting agitator speed to increase capacity in a CSTR comprising:
 a. measuring the HUT/BT and circulation ratio of the reactor,   b. measuring the mixing performance indicator of the final polymer product,   c. plotting the HUT/BT and circulation ratio vs the performance indicator,   d. varying the agitator speed or HUT to get a new HUT/BT and circulation ratio,   e. repeating steps a-d until the plotted line of step c shows a roughly horizontal lines (asymptote), and   f. lowering the agitation rate of the reactor for commercial polyethylene polymerization so the mixing performance falls within a “Zone II” or “Zone III” region on each plot from step c,   g. operate the CSTR reactor using the identified agitation speed.   
     
     
         29 . A method for transferring reaction conditions for an ethylene polymerization process from one plant to another comprising:
 a. measuring the HUT/BT and circulation ratio of a reactor system for the desired product,   b. setting up the reaction conditions in the new reactor to match the HUT/BT and meet or exceed the circulation ratio measured in step a.   
     
     
         30 . A method to improve the range of products that can be produced in a reactor system comprising:
 a) determine desired product characteristics and process conditions by modeling,   b. calculate or determine the HUT/BT and circulation ratio of the reactor system,   c. iteratively varying the reactor process conditions to get a new HUT/BT and circulation ratio in the model,   d. select the operating conditions that provide the desired determined product characteristics, and   e. run the process.