Water and wastewater services company United Utilities has agreed a contract for its first full-scale application of innovative sludge treatment technology from Holland. The installation at Kendal waste water treatment works in Cumbria will be the largest of its kind in the UK.

United Utilities developed the now-standard activated sludge process at its Davyhulme plant near Manchester over 100 years ago. Now, it says the innovative Nereda® granular sludge treatment technology will help to bring improvements to the process, following an intensive review of its applicability in the UK market.

“We were the first in the UK to invest in a pilot plant for Nereda at our Davyhulme treatment works – the very site where activated sludge was developed 100 years ago,” said Kieran Brocklebank, United Utilities Head of Innovation. “We’ve been hard at work testing Nereda since then in a number of applications. Moving away from a conventional process over 100 years old is difficult so we took our time to test Nereda across a broad range of criteria including purchase, running costs and specific technical parameters.”

Nereda® offers a number of advantages over conventional activated sludge due to the nature of the granules. Contrary to conventional processes, bacteria are concentrated into a compact granular structure with excellent settling characteristics. The compact structure also provides optimum conditions for simultaneous nitrification and denitrification as well as biological phosphorous removal.

Due to these factors, the Nereda® process can operate at high biomass concentrations, leading to compact reactor footprints - another key reason behind the decision to use the technology at Kendal WwTW.

United Utilities has signed the delivery contract with LiMA – a joint venture between Laing O'Rourke Construction and Imtech Process - working with the Nereda® technology provider, Royal HaskoningDHV.

Rene Noppeney, Global Director for Water Products and Innovation at Royal HaskoningDHV said: "Kendal treatment works is a great opportunity to demonstrate how Nereda® technology can deliver high quality effluent standards, low power requirements and sustainable costs."

Severn Trent Water announced yesterday that they were also to adopt the technology at sewage treatment works near Birmingham, to help them to meet stringent new water quality standards.

Image: Kendal waste water treatment works will benefit from a multi-million pound investment in the Nereda granular sludge treatment process