The Algae project at our Bran Sands Advanced Anaerobic Digestion (AAD) facility represents an innovation approach that aims to revolutionise wastewater treatment by using microalgae.
Bran Sands is a large sludge treatment centre, industrial effluent treatment site and gas to grid facility. Currently, the treatment process generates a challenging effluent that is costly to treat and contributes around 30% of the 15,000 tonnes of CO2 emitted by the Bran Sands gas to grid plant every year.
Off the shelf treatment options all involve breaking down ammonium to nitrogen oxides (NOx) which are released as greenhouse gases. This places a huge challenge on our net zero ambitions but also presented an unexpected opportunity when we discovered a unique microalgae growing in an out of service treatment cell. Through the implementation of an 8% scale microalgae plant, we can harness the remedial properties of microalgae meaning we will be able to reduce treatment costs by £170,000 a year, enhance biogas production, and significantly reduce our carbon footprint. We have already tested the treatment concept at smaller volumes and trialled different approaches and are now seeking to scale up the arrangements.
The project will provide full treatment of our digested sludge liquor which is around 5,500 tonnes a year.