Easy P-sy? Phosphorus 0.2-0.4 mg-Ptot/L in AMP6: PRESENTATION ONLY

Wickens, D., Luck, R. and Richards, A., Severn Trent Water, UK


In AMP6 (2015-2020) Severn Trent accepted 21 WFD or Habitats phosphorus limits below 0.5 mg-Ptot/L, nine of them at 0.2 mg-Ptot/L. Accompanying metals limits at 1 mg-Al/L (UT) and in the range 2.5-4.0 mg-Fe/L (95 %-ile) accompanied these. The sites had a range of populations from 700,000 down to 152.

The process of achieving the lowest Totex approach to each site led to two works closures, 18 pre-dosed Tertiary Solids Removal (TSR) systems, and one ballasted mixed liquor process. Of the TSR ten were cloth media filter solutions (of which four were two-stage), four were continuous sandfilters, three were multimedia filters, and one was a ballasted coagulation process.

This paper gives representative data from all the processes and reviews the commoner ones. All these sites were eventually successful. Most of the actual difficulties were not with phosphorus, but achieving the required low P at acceptable metals compliance, although several sites experienced unexpected side-effects with nitrification.

The conclusion is that no one technology was decisively more or less effective than the others. All also suffered from unreliability in the ancillaries: dosing pumps, TSR feed pumping stations and control software.

Please fill in your details to download the proceedings

For more information about how Aqua Enviro
can help you, contact us...

8 Appleton Court, Calder Park, Wakefield, WF2 7AR, UK

Consultancy and Laboratory services: + 44 (0)1924 242255

Conferences and Training enquiries: +44 (0)1924 257891


  • By submitting this form, you agree that we may use the data you provide to contact you with information related to your request/submission and other relevant Aqua Enviro services. You can unsubscribe from Aqua Enviro marketing emails at any time by clicking the unsubscribe link in the email. To learn more, see our Privacy Policy