Hach Lange Instruments Enable De-Sludging Trial
Severn Trent Water (STW) has initiated a de-sludging trial to reduce costs and energy consumption by producing thicker sludge in the Primary Settlement Tank (PST). Advanced monitoring instrumentation from Hach Lange played a key role in the trial. STW's Mark Bryan summarised the objective of the trial: 'We believed that if we could monitor and control the settlement process through a real-time control mechanism, we would be able to produce thicker sludge, reduce operational intervention and save the energy and costs involved with further sludge thickening prior to the sludge-digestion process. The trial took place at STW's Stoke Bardolph Sewage Treatment Works. Monitoring and control instrumentation was provided by Hach Lange and a hydraulically operated ram pump with an adaptive control system was provided by EMS Industries. A Sonatax SC probe was deployed for the measurement of sludge blanket level and a Solitax SC probe provided suspended solids and turbidity values. Al...