The Starlinger line took up operation in June 2024 in Ambiente’s new factory in Leiria, north of Lisbon, where the company recycles both industrial and domestic post-consumer plastic waste. A large share of it consists of discarded LDPE agricultural films and HDPE detergent bottles which Ambiente converts into pellets for film extrusion and blow molding applications.
“For us it is important that we produce a high-quality recycled product that can be reused in the same application,” said Paulo Pires, Managing Director of Ambiente S.A. “Our goal is to establish a circular economy. This means circularity within the respective application – for example, irrigation pipes become irrigation pipes again, agricultural film becomes agricultural film, food packaging becomes food packaging, and so on. Furthermore, we want to explore new applications for input materials with strong odors and high contamination levels. For this, all contaminants need to be eliminated as thoroughly as possible in the recycling process. That’s why we are investing in the best available technologies – from washing, extrusion and filtration to odor treatment. Our objective is to generate economic and environmental benefits by offering the plastics industry feedstock that is sustainable as well as competitive to make a circular economy become reality.”
Odor-improved recycled pellet
The recoSTAR dynamic 165 C-VAC recycling line installed at Ambiente features Starlinger’s renowned odor reduction technology and processes detergent bottles made of HDPE and washed post-consumer agricultural LDPE films. “Agricultural films are used for various applications – for example in greenhouses, as crop covering, or for silage. This results in organic residues being present even after washing which create gases in the subsequent recycling process,” explained Paul Niedl, Commercial Head of Starlinger recycling technology. “In case of packaging applications such as detergent bottles the smells of their contents migrate into the packaging material during their shelf life and usage time. Our odor reduction technology is designed to permanently remove such odors so that the produced regranulate is suitable for high-level applications. Instead of downcycling it can be reused in the same application, which creates circularity.”
To accommodate a wide range of input materials, the entire recycling process can be individually adapted according to the contamination and odor intensity of the input material and the desired specifications of the produced regranulate. The process starts with cutting and homogenizing the input material in the SMART feeder where the material is also heated until it reaches the ideal operating point. Highly volatile odors are extracted already during this process step. After the main extruder the melt passes through continuous melt filters where solid contaminants are removed so that they cannot release odors during the following process steps. In the subsequent C-VAC module the melt surface is increased by 300 %, achieving extremely high degassing efficiency. This ensures that even deeply embedded odors are permanently extracted. In the final step, the produced recycled pellets are treated in the pellet conditioning unit (PCU) at the end of the recycling process to extract the most persistent odors. This ensures permanently odor-improved regranulate that can be used for manufacturing a wide range of plastic products.
A Portuguese recycling pioneer
The roots of Ambiente S.A. reach back to 1953 when its mother company, the Portuguese plastic film production company Fabrica Leiriense de Plasticos, was already recycling internal production waste. From the early 1970’s on Fabrica Leiriense de Plasticos also processed externally collected plastic waste, including imported materials from other European countries such as Germany, and became Portugal’s recycling pioneer for domestic plastic waste in the 1990’s. The company management’s awareness that plastics recycling constitutes a fundamental prerequisite for a sustainable future led to the foundation of Ambiente S.A. in 1989. Since 2000 it is registered as an independent company, currently employing 36 people and recycling 7000 tons of post-consumer, industrial and domestic waste per year. The produced recycled LDPE and HDPE pellets are suitable for extrusion, blow molding and injection molding applications and are supplied to customers in Europe and Northern Africa.