Use of turbidimeter for measurement of solid catalyst system component in a reactor feed

A polyethylene production system comprising:

• a polymerization catalyst system comprising at least one catalyst and an activator support, wherein the at least one catalyst, the activator support, or both are a solid component of the polymerization catalyst system;
• a precontactor configured to receive the polymerization catalyst system via one or more precontactor feed streams, wherein at least one of the precontactor feed streams comprises at least a portion of the solid component;
• a precontactor effluent stream exiting the precontactor, wherein the precontactor effluent stream comprises at least a portion of the polymerization catalyst system;
• a polyethylene polymerization reactor configured to receive at least a portion of the precontactor effluent stream as a reactor feed stream, wherein the reactor feed stream comprises at least a portion of the solid component;
• and at least one turbidimeter for measuring a turbidity of a precontactor feed stream having a solid component therein, a turbidity of a precontactor effluent stream having a solid component therein, or both, wherein the turbidity of the precontactor feed stream, the turbidity of the precontactor effluent stream, or both are translated into a concentration of the solid component in the reactor feed stream.