Proceedings

Stoke Bardolph sewage treatment works

• STW’s second largest treatment works
• Located to the East of Nottingham, East Midlands
• Population served approximately 700,000
• Mix of trade and domestic sewage typical for a large catchment
• Clear example of an urban catchment
• Current discharge permit 25mg/l BOD : 5-10mg/l ammonia (seasonal)
• Future limit 1mg/l total phosphorus (under UWWTR)
• Also significant capital maintenance requirements

A quick aside – STW’s legacy of biological P removal & anaerobic digestion

• First bio P removal Activated Sludge Plant Derby, 2001
• 15 sites by end of AMP5
− A mix of sizes and flowsheets
• Population served by bio P over 4 million
• Approx 45% of total company population served
• Tonnes of iron saved… lots!
• STW has a landlocked region
• Wide deployment of anaerobic digestion of sewage sludge over generations of process engineers
• 100% of sludge is anaerobically digested, 100% of treated biosolids sent to agriculture

Waste water strategy – urban & rural catchments

“Over time we aim to operate an urban or rural philosophy for each catchment area…”
“… and to incorporate additional value-add opportunities into our business as usual operations, such as phosphorus recovery”