Abstract: A gas-phase polymerization system and a solids recovery system for a fluidized bed reactor. The fluidized bed reactor can include a fluidizing gas outlet from which a discharged mixture of fluidizing gas and polymer fines is released, and a cyclone separator can separate the polymer fines from the fluidizing gas for reentry into the fluidized bed reactor. It has been found that by situating the reactor entry nozzle of the fines return line which is closest to the gas-phase reaction zone significantly higher in the reaction zone than in a conventional fines return line, and by directionally orientating the incoming stream of polymer fines and carrier gas into the fluidized bed in the reaction zone, a significant increase in the residence time of the particle in the reaction and larger particles which meet a product size distribution specifications are achieved.

Abstract: A method of removing VOCs from a molten polymer comprising: (a) polymerizing monomers in a reactor to produce a reaction mixture comprising unreacted monomers and molten polymer, (b) removing a portion of unreacted monomers from at least a portion of the reaction mixture to produce recovered monomers and degassed molten polymer, wherein the degassed molten polymer comprises VOCs, (c) contacting at least a portion of the degassed molten polymer with an inert stripping agent at a pressure equal to or greater than atmospheric pressure to produce stripped molten polymer and spent stripping agent, wherein the inert stripping agent is insoluble in the degassed molten polymer, and wherein the spent stripping agent comprises at least a portion of the inert stripping agent and at least a portion of the VOCs from the degassed molten polymer, and (d) cooling at least a portion of the stripped molten polymer and forming polymer pellets.