Part of the FTSE 250 Pennon Group, Viridor provides the full range of recycling and waste services including advanced materials recycling, glass reprocessing, composting, mechanical/biological treatment, waste to energy, transport, collection, and safe and efficient landfill disposal. The company handles. 10.5 million t of material each year, recycling 2 million t and generating 101 MW of renewable energy.
In glass recycling Viridor handles all aspects of the process from collection and reprocessing of recyclable glass, to the marketing of high quality glass cullet to manufacturers, who turn the clean crushed glass cullet into new bottles or fibre glass insulation. Running advanced glass recycling technology at their Bonnyrigg and St Helens facilities, Viridor continues to lead and innovate in the sector in the UK. Viridor’s latest glass recycling investment is currently being commissioned at Salmon Pastures in Sheffield (Fig. 1). Its central location was chosen to process feed material from various sites in the UK at reasonable transport cost. Material from kerbside collections, bottle banks and from MRFs throughout the country can now be processed in the state-of-the-art processing plant using the latest available technologies.
Following a detailed tendering process Viridor selected the German company Mogensen GmbH & Co. KG as their chosen technology supplier and partner. For the Sheffield project it was Mogensen’s superior ability for screening, crushing, metal removal and colour sorting equipment plus their unique ability to meet Viridor’s high quality specification for the final cullet that led to their selection. During the engineering phase, Mogensen engineers travelled to various Viridor-sites around the UK to familiarise themselves with the individual future feed materials for the new plant. Multiple design meetings were held to discuss the best available technology, combining the experience of both partners (Fig. 2). The new glass plant will be fed with cullet from a number of different sources and has an overall capacity of up to 150 000 t/a.
The Mogensen-process starts with a variety of screens, an air conditioned handpicking station, a crushing system and metal removal units (Magnet plus Eddy Current) to remove waste, organics, ferrous and non-ferrous metals. The core of the new process is built by Mogensen’s latest colour sorting technology using several colour sorters type AX1223 to
• eliminate unwanted contamination, mainly CSP (Ceramics, Stones, Porcelain), to below 10 g/t,
• eliminate remaining metals; both ferrous and non-ferrous,
• clean and purify the different colours, mainly flint and amber, to furnace-ready quality.
An intelligent combination of cleaning and recovery procedures leads to high cullet quality. This allows Viridor to supply premium quality glass and achieve a high glass recovery rate from the feed, and thus helps towards Britain’s Zero Waste Policy.
Focus during the plant design was placed on detailed HAZOP (Hazard and Operability) studies, environmental mitigation measures and Health and Safety measures. Furthermore, to reduce environmental impact, the new plant was installed within an existing building. Manufacturing quality and reliability can be seen in the details of the facility. The steelwork of the plant is galvanized and the machines are powder coated and use stainless steel components. Wear protection is met by the use of hardfaced plates and special wear resistant steel. Access platforms are designed generously to allow simple inspection and good maintainability. To further increase the reliability, a modern Programmable Logic Controller (PLC) with Supervisory Control and Data Acquisition (SCADA) system has been installed. This system operates, controls and monitors the whole plant and captures the plant’s operational status instantaneously.
IFAT: Hall C1, Stand 227/326
Mogensen GmbH & Co. KG, Wedel (D),
Tel.: +49 4103 8042-0, www.mogensen.de