P removal
Schemes
Trialling innovative
technology
The UK wastewater industry has been challenged with improving effluent quality under the new Water Framework Directive (WFD) Phosphorus Standards. As part of this, a batch of nine schemes across Wales are required to meet the new 1 and 0.5mg/l P consents.
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Several projects had their consents challenged based on the work done in the Nutrient Offsetting Catchment Study. This allowed DCWW to argue a case for relaxing the consent at several wastewater treatment works and resulted in one of the projects becoming adopting a ‘do-nothing’ approach.
At another project, sample data and a risk-based approach was used to demonstrate that tertiary treatment was not required.
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Opportunity
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The remaining sites were used by DCWW as an opportunity to trial various new technologies across the business, in order to achieve the tighter P consent by 31st March 2020.
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Following the trial, DCWW and MMB evaluated the effectiveness of the technologies, their commercial viability, reliability, and maintenance requirements, allowing informed decisions to be made during AMP7, when more P-schemes are expected to be delivered.
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Trialled technologies
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Blue Water Bio - FilterClear Tertiary Solids removal
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FilterClear is high rate multi-media filtration system. It utilises four types of media which results in a high quality of filtered effluent. Whilst this technology has never been used in DCWW, MMB have experience working with this technology in Severn Trent Water and have been able to draw on this experience to ensure seamless delivery of the project.
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Benefits include:
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Small footprint
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Off site fabrication and testing allowing 2-week installation and commissioning period
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Capacity to achieve future tightening of consents
Evoqua – CoMag® Enhanced Solids Removal
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The CoMag® system uses magnetite to enhance the clarification process. The system settles chemical floc up to 30 times faster than conventional treatments, enabling plants to increase capacity and enhance clarifier performance. The Magnetite is added to the reactor, settlement is accelerated, and the magnetite is separated continuously. The magnetite is then recovered and re-used again.
Benefits include:
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Capacity to achieve future tightening of consents - easily achieves low T-P requirements of less than 0.25 mg/l.
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Low maintenance equipment and reliable for operations
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Can cope with higher loads with no loss of throughput.​
Want to learn more? Speak to Rosie Green @ MMB