Patent ID: 8648156

Claim:
A process for polymerisation in a slurry loop polymerisation reactor, which reactor comprises: a) a reaction zone in the form of a slurry loop and having a volume of at least 50 m 3 and an internal diameter (D) of 50 cm or greater, b) at least one feed inlet for monomers and diluent, c) at least one catalyst inlet for polymerisation catalyst, and d) at least one discharge conduit for removal of polymer, and which process comprises passing monomer, diluent and catalyst into the reaction zone through their respective inlets, and wherein they react to form a slurry of polymer solids having a concentration of polymer solids in the reaction zone of greater than 20 wt %, being the weight of polymer solids relative to the total weight of the slurry (solids and liquid), wherein the process is operated at a space-time yield (STY) greater than 100 kg/h/m 3 , and wherein the at least one catalyst inlet is in the form of an inlet pipe and no part of the inlet pipe protrudes beyond the wall of the reaction zone and into the reaction zone by more than 1/10 th of the diameter of the reaction zone at the point where the inlet pipe joins the reaction zone.