Uskmouth - Gwent, Wales, United Kingdom Energy

 

The client

The Uskmouth Power Station located at Gwent, Wales is operated by Alstom on behalf of Carron Energy.

Uskmouth is a 360 MW power station with three independent coal-fired units. Those underwent significant refurbishment in 2000 giving a 25-year life extension to the plant and allowing compliance with the latest environmental standards.

The site comprises 96 hectares of land and has a 1,250 MW connection to the National Grid, presenting opportunities for further development.

The client's needs

Make-up water for the high pressure boilers which are feeding the power conversion turbines is piped from Nash wastewater treatment plant as tertiary treated effluent.

It must be treated on site to reach ultra pure water quality.

The Uskmouth power station was looking for a partner able to supply process water with guaranteed quality and continuity in service delivery.

Our solution

In order to meet Uskmouth's requirements Veolia Water has designed and built a plant consisting of ultrafiltration and base exchange softening pre-treatment followed by three reverse-osmosis units, with three mixed-bed demineralization units (two regenerable and one cartridge unit for use during the regeneration of the mixed bed plants).

The treatment line consists of:

  • one chloro-amination plant (ammonia and chlorine dosing)
  • one ultrafiltration plant
  • one duplex (service standby) base exchange softening plant
  • three reverse-osmosis streams fed with recovered tertiary treated effluent
  • two mixed-bed ion exchange units and cartridge mixed-bed unit
  • regeneration of the mixed-bed resins with acid and caustic chemicals

Veolia Water has also been contracted to operate and maintain the facility, in order to continuously produce demineralized water with an average flow of 45 m3/hr (two units in service and one in standby) with a 25 m3/hr flow rate at low generation periods with one plant on-line and two in standby.

Originally using potable water as feed, the revised configuration was signed in 2006 to increase the capacity of the plant utilizing a cheaper form of feed water, namely tertiary treated effluent.