Apparatus (1) for degassing of gaseous components from at least one curable material (2), particularly a curable material, for building a composite part, particularly a rotor blade for a wind turbine, the apparatus comprising:

- at least one degassing chamber (3) having at least one inlet (5) for introducing a curable material (2) for building a composite part, the curable material containing gaseous components, into the degassing chamber (3) and at least one outlet (7) for removing a degassed curable material (2) from the degassing chamber (3), and

- at least one mechanical splitting means (13) adapted to mechanically split up gaseous components contained within the curable material (2) so as to release the gaseous components from the curable material (2).

A static devolatilisation apparatus 1 adapted for devolatilising a viscous liquid 2 comprising a volatile component is disclosed. The apparatus 1 comprises a phase separation chamber 100 in an upper region 5 for treating the viscous liquid 2 in a first devolatilisation step to form a first devolatilised viscous liquid 21, and a distributor sub-unit 200 is located below the phase separation chamber 100 and above a lower sump region 4. The sub-unit 200 has a second discharge region 222 embodied such that it is contacted by the first devolatilised viscous liquid 21, and the region 222 has a surface 223 embodied such that the first devolatilised viscous liquid 21 is treated in a second devolatilisation step. The present invention further relates to a process to devolatilising a viscous liquid using the apparatus 1 and also to the use of the apparatus 1 in the devolatilisation of polymer melt or solution.

Process for treating polyolefin particles obtained by gas-phase polymerization of one or more olefins in the presence of a polymerization catalyst system and a C₃-C₅ alkane as polymerization diluent in a gas-phase polymerization reactor, the process comprising the steps of

a) discharging the polyolefin particles continuously or discontinuously from the gas-phase polymerization reactor and transferring the particles to a first degassing vessel;

b) contacting therein the polyolefin particles with a gaseous stream comprising at least 85 mol-% of C₃-C₅ alkane while the polyolefin particles have an average residence time in the first degassing vessel of from 5 minutes to 5 hours;

c) transferring the polyolefin particles to a second degassing vessel;

d) contacting therein the polyolefin particles with a stream comprising nitrogen and steam while the polyolefin particles have an average residence time in the second degassing vessel of from 5 minutes to 2 hours;

e) transferring the polyolefin particles to a third degassing vessel;

f) contacting therein the polyolefin particles with a stream of nitrogen while the polyolefin particles have an average residence time in the third degassing vessel of from 5 minutes to 8 hours,



and processes for preparing polyolefin polymers by gas-phase polymerization of one or more olefins in the presence of a polymerization catalyst system and a C₃-C₅ alkane as polymerization diluent in a gas-phase polymerization reactor, wherein the obtained polyolefin particles are subjected to such a treating process.

Process for preparing a polyolefin polymer comprising the steps of

a) forming a particulate polyolefin polymer by polymerizing one or more olefins in the presence of a polymerization catalyst system in a polymerization reactor;

b) discharging the formed polyolefin particles from the polymerization reactor;

c) degassing the polyolefin particles by a process comprising at least a final step of contacting the polyolefin particles with a nitrogen stream in a degassing vessel; and

d) transferring the polyolefin particles from the vessel, in which the contacting of the polyolefin particles with the nitrogen stream is carried out, to a melt mixing device, in which the polyolefin particles are melted, mixed and thereafter pelletized, without passing the particles through a buffering device,



wherein the degassing vessel is only partly filled with polyolefin particles and the empty volume within the degassing vessel is sufficient to take up additional polyolefin particles for at least 3 hours if the transfer of polyolefin particles of step d) from the degassing vessel to the melt mixing device is discontinued and the discharge of polyolefin particles from the polymerization reactor according to step b) is continued with unchanged rate.