Site Solutions work with one of the largest food waste AD plants in Wales which handles a major portion of food waste in the region surrounding it. The site uses multiple digesters to convert food waste into renewable energy and fertiliser.
How a digestate tank works:
- Food waste is depackaged – the packaging being separated for recycling or energy recovery and the organic portion being mixed with water to form a slurry, which is then pumped into the digester tanks.
- The tanks are sealed, heated, and continuously stirred, allowing microbes to break down the waste and produce methane-rich biogas.
- The biogas rises to the top of the tank, where it is captured and used for energy production, while the remaining digestate and grit stay in the tank for further treatment or disposal.
The team manages three waste streams: AD Fibre (the solid portion of the digestate), AD Grit, and AD Plastics. Fibre and grit are byproducts of the anaerobic digestion process. AD Grit remains in the digestate tanks until it is ready to be pumped or dug out, while AD Fibre is collected continually and stored separately. The plastic element of the packaging separated prior to the waste entering the digestate tanks is collected in bulk and managed by our team.
The images above show bulk AD Fibre stored on site ready for collection, AD plastics after the separation process and the inside of a digestate tank where grit has accumulated at the bottom.
Site Solutions work with the site to organise the most efficient and cost-effective methods for collecting and compliantly disposing of three waste types: AD Grit, AD Fibre, and AD Plastics.
Using our network, we collect AD Plastics and AD Fibre (mostly by walking floor), which are then transported to third-party sites for energy-from-waste recovery. AD Grit is collected separately (mostly by tipper transport) and processed through an In-Vessel Composting (IVC) system, where it was pasteurised and treated in the tunnels to form Compost Like Output (CLO) which can be used for site restoration.
The Site Solutions team continue to work with the site for the collection, transportation, and further treatment of these waste streams, ensuring compliance at every stage.
