Monitoring and control of slurry processes for polymerizing olefins

A process for olefin polymerization in a slurry comprising solid polyolefin and a diluent, said process comprising the steps of:

• (a) contacting in a reaction mixture under slurry polymerization conditions within a loop polymerization reactor:
• (i) at least one reactant comprising at least one olefin monomer and optionally at least one comonomer and optionally hydrogen;
• (ii) a heterogeneous catalyst system comprising one or more catalytic metal compounds and one or more cocatalysts;
• (b) making a polyolefin;
• and
• (c) monitoring the process by using Raman spectrometry equipment by analyzing effluent from said loop polymerization reactor to provide an output signal representative of one or more of said reactants or said polyolefin.

A process for olefin polymerization in a slurry comprising solid polyolefin and a diluent, the process comprising the steps of:

• (a) contacting in a reaction mixture under slurry polymerization conditions:
• (i) at least one reactant comprising at least one olefin monomer and optionally at least one comonomer and optionally hydrogen;
• (ii) a heterogeneous catalyst system comprising one or more catalytic metal compounds and one or more cocatalysts;
• (b) making a polyolefin;
• (c) monitoring the process by using Raman spectrometry equipment to provide an output signal representative of one or more of said reactants or the polyolefin;
• and
• (d) adjusting the olefin polymerization process in response to the output signal provided by the Raman spectrometry equipment;
• wherein the olefin polymerization process is performed in two or more reactors connected in series, wherein effluent from an upstream reactor is provided as input to a downstream reactor, wherein the monitoring step comprises determining a concentration of the monomer in the effluent by Raman spectrometry equipment, and the adjusting step comprises providing an amount of monomer or comonomer in addition to the effluent to the downstream reactor.

A method for monitoring and controlling an olefin polymerization reaction comprising:

• (a) contacting components of a reaction mixture in a polymerization reactor under polymerization conditions, said components comprising a monomer, a diluent, and a catalyst system;
• (b) using Raman spectrometry equipment to obtain a Raman spectrum;
• (c) obtaining a concentration of at least one said component based upon said Raman spectrum;
• (d) adjusting at least one polymerization condition in response to said concentration of said component.