- where we work
Completed: 09/02/07
sonix™ - Minworth.
Energy
Severn Trent Water operates over 1000 sewage works and 43 sludge treatment centres providing water and sewerage services to over 3.7 million households and businesses in the Midlands and mid Wales. About 15,000 dry tonnes per annum of biosolids are produced of which about 75 % is recycled to agriculture. The majority of raw sludges are anaerobically digested and in recent years combined heat and power systems (CHP) have been installed with a total capacity of 30 MW. Severn Trent Water’s strategy of increasing income, reducing carbon footprint and reducing the quantity of biosolids for recycling has resulted in digester optimisation and the assessment of sludge technologies that enhance sludge digestion to increase gas production.
The need to generate income from electricity production is now one of Severn Trents key performance indicators. Alongside this are the other strategic requirements of reducing the carbon footprint and reducing the quantity of biosolids for recycling. Maximising gas production from the Mesophilic Anaerobic Digestion (MAD) process to generate power is a key requirement for Severn Trent Water.
Currently the value of Renewable Obligation certs (ROCs) or “Green credits” and the expensive cost of disposal are driving all water companies in the UK to look at means of enhancing their anaerobic digestion facilities performance (c. 50% of sewage treatment costs are associated with sludge treatment). Elsewhere in the world sonix™ has demonstrated the ability to release more biogas from anaerobic digestion and reduce the solids requiring recycling / disposal. The Minworth project forms the basis of a potentially large supply framework for digestion enhancement throughout the region.
