Patent ID: 7557180

Claim:
A reactor for solid phase continuous polymerisation of polyethylene terephthalate (PET), comprising: a casing; a feeding line to feed a low molecular weight PET pre-polymers flow into said reactor; a gas line to feed, through supply valves, a gas into said reactor; a discharging line inferiorly connected to the bottom of the reactor to discharge the polymerised product; a circuit connected to the reactor to purify the gas and to recover pre-polymer particles by means of a proper separator; wherein, said casing of said reactor is horizontally arranged; and wherein, inside said reactor, means are provided to generate a plurality of fluidised stages in series to cause an increase of the intrinsic viscosity (I.V.) of said PET pre-polymers flow; and wherein in correspondence with each fluidised stage a sufficient gas flow is generated by said supply valves, each valve being equipped with a heating device, wherein said I.V. increase of said PET pre-polymers flow is ≧0.06 dl/g.