The Plant for production of high density polyethylene - HDPE, started in 1975. It is based on the process technology Phillips Petroleum Co (today-Chevron Phillips Chemical Company-USA), and it was constructed according to the project Crawford & Russell (USA). Trade name of HDPE is HIPLEX®.
This technology for HDPE production (’’Particle form’’ - PF) stands out among the others according to the quality of the got polymer,energy exploitation and small emission of harmfull matters into the atmosphere.In this way polyethylene is got by polymerization of ethylene in the stream of liquid isobutane with the presence of catalyst chrom-dioxide on alumo-silicate basis in continuous pipe reactor on the temperature up to 110 °C and pressure of 42 bar.
Process of high density polyethylene production - HDPE,represents continual operation in which monomer polymerizes ethylene in the presence of catalyst.Isobutane is used as medium in reactor (LOOP) with the purpose of maintaining polymers and catalysts in the form of suspension.For production of copolymers in reactor are added small quantities of comonomer hexene-1. Reaction of polymerization is exothermic.For control of operation of the whole system there are used distributive control system (DCS) and programable logic controllers (PLC). The formed polymer is separated from hydrocarbons by reduction of pressure (flashing) of suspension and by heating,on which occasion hydrocarbons (isobutane,nonreacted ethylene and hexene) evaporate and are separated from polymer powder.After separation,hydrocarbons are returned to reactor through recycle section.Powder is transported to further processing i.e. granulation,storage and packing.
HDPE Plant consists of three technologically connected units – sections: PF section in which there is performed activation of catalyst and reaction of polymerization,section of processing in which the got polymer powder is extruded in pellets and section of packing and storage.
