Developing a long term strategy for sludge treatment at Beckton and Crossness STWs
Konig, P.1 and Newton, J.2, 1 Thames Water, UK, 2Mott MacDonald, UK
(free)
Thames Water (TWUL), while undertaking a company-wide review of its sludge strategy, identified a need for additional sludge treatment capacity in the East London area. In particular, it is expected that the quantity of sludge produced at Beckton STW and Crossness STW – together serving over 5 million residents of London – will increase significantly due to population growth, tighter environmental regulations and planned upgrades of existing wastewater treatment facilities during AMP 4 and AMP 5.
Currently, the bulk of existing sludge production is treated using the Sludge Powered Generators (SPGs) at each STW which incinerate the sludge, producing an ash for disposal, and use the heat from the incineration to create renewable power. The SPGs do not have the capacity to incinerate all of the sludge produced at each site and therefore rely on other, short term, solutions including lime treatment of sludge cake, to treat the surplus.
In 2008, TWUL, assisted by Mott MacDonald, undertook a Strategic Alternatives Review (SAR) to investigate site-specific options for dealing with the shortfall in capacities at Beckton STW and Crossness STW. The SAR considered a range of factors including technical, economic and environment (including carbon emissions) and identified a preferred medium and long term strategy for each site including major schemes for implementation in AMP5.
The presentation will cover the background to the SAR, the key issues considered and the findings with respect to the medium and long term strategy for sludge treatment in East London.
