| 摘要 |
The present invention relates to a start-up process of a continuous gas fluidised bed process for the polymerisation of olefin monomer selected from (a) ethylene, (b) propylene, (c) mixtures of ethylene and propylene, and (d) one or more other alpha-olefins mixed with (a), (b) or (c), in a fluidised bed reactor by continuously recycling a gaseous stream comprising at least some of the ethylene and/or propylene through a fluidised bed in said reactor in the presence of a polymerisation catalyst under reactive conditions, cooling at least part of said gaseous stream withdrawn from said reactor to a temperature at which liquid condenses out, separating at least part of the condensed liquid from the gaseous stream, and introducing at least part of the separated liquid directly into the fluidised bed using a liquid injection means, characterised in that at least part of the gaseous recycle stream by-passes the hereabove cooling/condensing/separating steps, and is reintroduced as the recycling gaseous stream passing through the reactor. |
