Integra Plastics, Rosen Tzankov: Automatic sorting systems are among the main weapons in the battle against plastic waste

Rosen Tzankov, Plant Manager at Integra Plastics, for South-East European Industrial Market

Please tell our readers more about the innovations featured in Integra Plastics’ business concept and about the most advanced technologies implemented in your plant in Elin Pelin.

In 2017, the People’s Republic of China announced a ban on the import of waste plastics, which led to a major shock in the secondary products market around the world. Europe was by this time “comfortably” used to exporting much of its plastics, and this ban put a lot of stress on global environmental sustainability, as well as on the ability to handle the recycling of this waste. A large supply of raw materials appeared, and the production capacity turned out to be too small.

This was an ideal opportunity to create a facility that would meet the highest quality expectations for secondary low density polyethylene (rLDPE) granules. Thus the conceptual project of the plant was born – to produce regranulate of the highest quality in order to replace the primary material used in packaging to the maximum.

Behind Integra Plastics’ project are leading companies in the field of recycling with innovative solutions for sorting, washing and extruding recyclable plastics. The Norwegian company Tomra, leader in the field of optical sorting, provided a solution that guarantees over 98% purity of the polymer in the final product. In addition to the qualitative indicators, the quantitative indicators are also high – the capacity allows the sorting of 35 000 tons of material per year. In combination with a transport system from the German company Stadler, which has over 200 years of experience in the market, the plant achieves enviable results for the entire industry.

Subsequently, the sorted bales of polyethylene enter the “Washing and Extrusion” workshop. Here, Integra again relies on top-class equipment – from the German company Herbold and from the Austrian leader in the field of extrusion Erema. Daily analyses of numerous indicators that are important to consumers are performed at our state-of-the-art laboratory at the plant in Elin Pelin. This helps monitor the flawless running of the recycling processes.

What is the specific added value of automation in the circular economy?

Automatic sorting systems, like the one at the Elin Pelin plant, are one of the main weapons in the battle against plastic waste. They allow processing tens of times faster than manual processing. Through high-speed cameras and NIR-VIS sensors, optical sorters manage not only to separate at high speed, but also to recognize materials that even a well-trained person could mix up. Until recently, waste plastics were turned into low-quality granulate, which is inapplicable in the same production. An example of such a raw material is low-density polyethylene (LDPE), which, after recycling, could not be returned to the production lines for blow sacks and waste bags due to its low quality. Today, it is quite possible to use the granulate again for the same type and class of products. Automated processes, where accuracy and quality are a constant, make a huge contribution to this.

Walk us through the production process at your plant.

The Integra Plastics plant is designed to process films from pre-separated low density polyethylene. The raw material arrives at the site in the form of bales. After unpacking, the material is fed to a shredder to reduce the size to pieces suitable for sorting. A magnetic separator removes ferromagnetic metals, and a vibrating screen removes inert contaminants. The entire flow passes through ballistic separators that separate all bulk plastics. The LDPE film goes through several more processing steps using the latest generation optical sorters. A computer program controls which colours are sorted as a separate fraction and which are collected as a mixed fraction. The separated quantities are stored temporarily in hoppers managed by an operator who feeds a baling machine.

The finished polyethylene bales are sent to the washing workshop, where they are de-baled again. After shredding, the material goes through preliminary, basic washing with warm water and detergents, rinsing and drying. Finally, it enters a silo, from which the extruders are fed. They are equipped with laser filters, which ensure the highest degree of purification of the melt and the extremely high quality of the final product.