POLYOLEFIN DRAG REDUCING AGENTS PRODUCED BY NON-CRYOGENIC GRINDING

摘要

Fine particulate polymer drag reducing agent (DRA) in bi-modal or multi-modal particle size distributions may be produced simply and efficiently without cryogenic temperatures. The grinding or pulverizing of polymer, such as poly(alpha-olefin) suitable for reducing drag in flowing hydrocarbons may be achieved by the use of at least one liquid grinding aid and at least two grinding processors in series. The impellers of the grinders are of different openness so that granulated polymer fed to the first processor having a relatively more open impeller is ground to an intermediate size which is fed to the second processor having a relatively more closed impeller which grinds the polymer to a second, smaller size. A non-limiting example of a suitable liquid grinding aid includes a blend of propylene glycol, water and hexanol. Particulate DRA may be produced at a size of about 300 microns or less in only two passes.