COOK is a true pioneer of frozen food in the UK. The business was born from the idea of freezing home-cooked meals and puddings, to avoid using the additives and preservatives frequently found in mass-produced ready meals. Everything from pies to curries and strudels are made as you would at home, then frozen, ready to be heated straight from frozen in your oven or microwave. From one tiny shop in Farnham, Surrey, and a little kitchen in Kent, COOK has grown to have 105 shops nationwide and four, big kitchens, with sales of £130m. COOK has also been a pioneer when it comes to ethical business. In 2013, it became one of the very first certified B Corps in the UK, passing a tough, independent test to assess its impact on people and planet. This puts COOK in esteemed company alongside other B-Corp pioneers such as Tony’s Chocolonely, Patagonia and Tom’s.
With regards to their passion for sustainability, COOKs Sustainability and Technical Director Richard Pike engaged with WASE to determine whether there was an opportunity to convert food production waste (such as pie crusts and left over sauces) into biogas, reducing the carbon impact of their operations.
‘The drivers for engaging with WASE were driven by a need to reduce our reliance on green gas bought from the grid, improve circularity and lower our waste treatment costs. WASE offered a solution that could address all three of these points, so was really keen to trial the system and see how it worked.’ – Richard Pike
WASE installed a small version of their electro-methanogenic reactor called ‘miniWASE‘ at the COOK pudding site in Ilton, where the intention was to demonstrate that the system could handle a small volume of pudding production by-products and convert them into biogas, whilst removing >90% of the COD (organic strength). Once the system could effectively demonstrate its biogas performance, plans would commence on a full scale system to treat a much higher volume of food production by-products.
‘The miniWASE system installed at Ilton was converting left over pudding waste, which is ordinarily collected by a haulier and taken to a merchant AD site for further treatment. Now we were able to convert this into biogas on site and reduce the strength of the wastewater. The system was set-up quickly and started generating gas very quickly too. This is a really good example of the circularity and sustainability we are looking to achieve at COOK. The next steps for us now are to start working on the larger installation opportunity at our principle production site in Sittingbourne, where we should be able to unlock considerable carbon reductions and cost savings.‘
The WASE team operate the miniWASE system for the duration of the pilot, taking regular samples to maximise the performance of the equipment. These interventions help WASE to determine what the full scale biogas and organic removal performance would be when scaled up to a much higher volume of wastewater throughput.
The organic strength of the pudding byproducts has been highly variable (changing depending on what is being baked that day) and highlights how resilient the WASE system is at handling fluctuating CODs. Over a period of a week, the system treats byproducts with a 10,000-78,000mg/l COD. This level of organic strength variation would cause a catastrophic impact to the microbiology in a traditional Anaerobic Digester.
The WASE science team have been working to test how far they can take the miniWASE system with the pudding byproducts and have ramped up the organic loading rate (OLR) to 9kg/COD/m3/day and have a hydraulic retention time (HRT) of 8days. The intention is continue to build the OLR even higher and reduce the retention time even further with the remaining time left on the trial.
Piloting the miniWASE system is a great way of demonstrating how the innovative WASE electro-methanogenesis solution works on a small scale, at a low-cost and with minimal disruption to site, helping build a data-backed business case for a future full scale installation.
Reach out to the team at WASE here to learn more about WASE and whether you too could pilot WASE on your site!
