Waste Sorting : Stadler supplies high-efficiency MRF and Compost Refinement plants for Terna Energy

The renewable energy company Terna Energy, part of the Gek Terna Group, is a leading player in the production of clean energy and the largest investor in renewable energy in Greece. It is also consolidating its role in sustainable development and the circular economy through its integrated waste management projects. For this activity, the company has chosen STADLER, the global German company specialised in the design, manufacture and installation of turnkey recycling and sorting plants, as its strategic partner in public-private projects for the design and installation of Materials Recovery Facilities (MRF) in the region of Epirus and now also in the Peloponnese. STADLER has now completed the commissioning and start-up of its latest facility, an MRF and composting plant in Tripoli, the capital of the Peloponnese region, with two further projects in Sparta and Kalamata underway.

The new plant is characterised by a high degree of automation and efficiency, as well as the ability to adapt to changing material composition. It produces consistently high quality output and achieves excellent recovery rates - over 90% for the organic fraction, plastic containers, bottles and paper, and 80% for biofilms and PE film. It is also designed for easy maintenance, with all components and motors easily accessible for servicing.

The sorting plant receives mixed municipal solid waste (MSW) on a single line with an input capacity of 30 to 40 tonnes per hour. It is processed to produce a high quality output of recyclates and organic material. The former - PET, HDPE, PP/PS, film, paper, cardboard, ferrous and non-ferrous cans and containers - are sorted into automatic bunkers and then baled. The latter, in fractions of less than 60mm from anaerobic digestion and 65-85mm from container composting, are further processed in the 10tph compost upgrading plant, producing two fractions of clean compost with different specifications and material sizes.

STADLER's design team developed a plant that would deliver the high quality output required by Terna Energy, effectively meeting the challenge posed by the specific nature of the waste stream in the region: "The Peloponnese is a very touristic region and this has an impact on the composition of the waste, with high variations in seasonal consumption and the variety of packaging," explains Dimitris Blanas, Head of Sales Greece & Middle East at STADLER.

Starting with two trommel screens, the process is followed by a STADLER STT5000 ballistic separator, which separates the rolling, flat and screened fractions. At this stage of the process, Pellenc ST COMPACT optical sorters, seamlessly integrated with STADLER high-speed conveyors, are used to sort waste by material and colour on the two main lines: 2D for flat objects such as mixed paper, cardboard and film, and 3D for hollow objects such as bottles, containers and trays. These sorters, equipped with Pellenc ST's latest advanced technology, are perfectly suited to the task thanks to their compact size, low energy consumption and high performance, as well as their ability to handle the volumes and variations in the feed: “The high capacity of this equipment will be able to absorb the increase of waste volumes, says Steve Halpin-Gosset, Regional Sales Director, South Europe at Pellenc ST. “Thanks to their high scalability, sorting settings can also be adapted according to input stream composition changes.”

“We had a very short time for completing the assembly and the plant was required to run at full capacity on the first day of hot commissioning, because of the high volumes of municipal waste arriving and the lack of storage facilities,” explains Dimitris Blanas. Close collaboration between the teams from Terna Energy, technology partner Pellenc ST and suppliers was key to meeting the deadline. “We focused on effective coordination of all the teams, as well as careful timing of deliveries ahead of assembly to avoid wasting any time. Also, detailed checks and meticulous preparation throughout the assembly and cold commissioning phases were critical.” Steve Halpin-Gosset adds: “We have been working with STADLER for many years and have built a strong partnership. The quality of our relationship and the smooth interactions between our teams have guaranteed the success of this project.”

The entire project unfolded to the satisfaction of Terna Energy, as expressed by Diomidis Kamoutsis, Project Manager, who appreciated “STADLER’s solid design and quality equipment, together with the effective management of the project in all its phases – from designing to delivery, construction and commissioning. Their team was always available, fast in responding whenever an issue arose, coordinating and supporting the construction team, effectively collaborating with the other providers and suppliers on site. The fast delivery and installation were impressive.”

Within the framework of its partnership with Terna Energy, STADLER has designed two further MRF and composting plants with similar characteristics and capacities in the Lakonia and Messenia areas, also in the Peloponnese, which are expected to be operational in the autumn. STADLER will support the three plants with a local service team and a dedicated maintenance warehouse. These three plants, together with the plant designed and built by STADLER in Epirus, will be the most advanced MRF sorting plants in operation in the country.