Low Density Polyethylene Plant – LDPE was built and put into operations in 1979 on the basis of process technology of National Distillers Co (USA), and according to the design of Foster Wheeler Co (USA).
Polymerization of ethylene takes place in the autoclave reactor under high pressure up to 2.000 bar. Continuous production on one line, with the so far achieved capacity of 57.000 tons per year, provides products in the form of granules. The basic sections of the process are synthesis sections, then the silo section, packing and storage section.
Fresh ethylene with stream of return ethylene from the system for flash gas is introduced into the system of primary compression, which is compressed to 245 bar. In the system of secondary compression, when needed, the pressure is raised to 2.000 bar. Under these conditions, gas is introduced into the reactor in which, by the help of the initiator, the reaction of polymerization starts. The resulting polymer is cooled and taken to the high-pressure separator so that non-reacted gas, which goes into the system for recycling, could be separated. Polyethylene is then introduced into the low pressure separator, and from there to the extruder. From the system of extrusion, obtained granules are transported to the silos, where aerization is done, in order to eliminate traces of ethylene and obtain uniform polymer. By pneumatic transport, granules are transferred to two automatic packing lines. The polymer is packed in 25 kg bags and put on the pallets. Process technology allows obtaining different types of products with different characteristics, suitable for a wide range of applications.
Trade name of LDPE is HIPTEN®. It is used for various processing techniques, from film extrusion, foils and plates, to blow molding and injection of products for various purposes.