Keldgate Water Treatment Works – Nitreat® Removal Plant

The largest plant of its type in the UK

Keldgate Water Treatment Works (WTW) is a vital site located in Yorkshire and it is integral to supplying potable water to the city of Hull. It was commissioned in 2010 and has a capacity of 90Ml/d.  

Keldgate WTW draws groundwater from natural borehole supplies and is located in a rural farming area, which is identified as one of Defra’s Nitrate Vulnerable Zones. With the rise in Nitrates in the raw water feed to Keldgate WTW, Yorkshire Water Services (YWS) needed to install a nitrate removal system to secure future compliance having an undertaking with the Drinking Water Inspectorate (DWI) to provide a solution to the water quality problem.

Innovative solution: Use of Nitreat® ion exchange technology for nitrate removal from drinking water.

It was determined that the best solution would be to install a nitrate removal stage based on Ion Exchange downstream from the existing membrane filtration system.

ACWA’s successful solution was to design and install three Nitreat® Skid mounted systems capable of reducing the Nitrate levels within a proportion of the raw water feed down to less than 5mg/l before blending back with the remaining flow to produce a blended treated water quality with a discharging Nitrate level of <42mg/l.

ACWA solution included Salt saturators (brine) and water softener systems along with feed pumps, inline strainers and monitoring stations controlled from a MCC Panel.

ACWA’s unique design operates continuously treating the raw water through a large proportion of resin vessels whilst regenerating the resin in the remaining vessels simultaneously; this negates the need for a system shutdown for resin regeneration purposes.

Benefits and outcomes:

  • Designed to minimise the treatment building footprint
  • Built with redundancy for future treatment flow requirements
  • Simple to operate and maintain
  • Designed to produces very little waste liquors
  • Designed to optimise Power and Salt consumptions

Key facts

  • Largest plant of its type in the UK
  • Ion Exchange technology offered most cost effective solution in terms of both Capex and Opex
  • Turnkey M&E Project
  • Flow – 3,750m3/h (90MLD)
  • Raw Nitrate up to 63mg/l
  • Nitrate Target – <42mg/l