One of only two desalination plants in the UK
ACWA Services Ltd, part of the ACWA Group, a leading international water and wastewater solutions provider, will start work on site in September 2015 on a major upgrade and modernisation programme for Jersey’s La Rosière desalination plant, to improve security of supply during periods of low rainfall, increase capacity and reduce running costs.
Owned and operated by Jersey Water, La Rosière desalination plant is an essential standby facility used to top up the island’s Val de la Mare reservoir during prolonged dry periods. The first desalination plant in the UK, Jersey Water last upgraded La Rosiere in 1999. The modernisation works will bring the plant right up to date, providing a highly resilient and efficient fresh water solution. At the same time, the plant will almost double in capacity to take account of changing climate conditions, population growth and summer demand from tourism.
The turnkey solution comprising design and procurement through to installation and commissioning, will see the complete redesign and expansion of the existing seawater reverse osmosis (SWRO) process streams with new pressure vessels, an additional dual media filter, next generation high capacity RO membranes, pre-treatment systems and associated equipment. To keep the plant footprint small and to satisfy demanding island planning authority constraints, all new technology and equipment will be situated within the existing facility.
The new plant will take fresh water production when the plant is online, from the current capacity of 6 million litres per day, up to 10.8 million litres. ACWA’s design allows for potential future expansion to 15 million litres per day, ensuring additional longevity for the plant should demand grow further.
In addition ACWA is specifying a state of the art energy recovery system that recovers hydraulic energy from the reject stream of concentrated brine, the liquid left over after salt has been extracted from the treated water. This will reduce energy use at the plant by 36% – a significant improvement over the current existing plant.
Helier Smith, Chief Executive at Jersey Water said: “ACWA’s track record and international experience with desalination and advanced water treatment technology, makes them a perfect partner for this critical water industry infrastructure project on Jersey. With the current plant at the end of its serviceable life, ACWA’s solution will increase capacity and resilience for the Island’s public water supply in times of low rainfall and built-in energy recovery will ensure that running costs are lower when the plant is online.”
Peter Brewer, ACWA Services Ltd General Manager added: “We are delighted that Jersey Water has selected us for this crucial desalination infrastructure project. With a tight programme to achieve all the upgrades in time for the summer months when the plant may be required, our combined process, mechanical and electrical engineering disciplines are keen to get working. To overcome strict Planning Authority constraints and limited space on site, we have included measures to use the existing buildings and ancillary equipment to their maximum potential, whilst offering the most robust solution. The hi-tech energy recovery technology also gives us the flexibility to vary the reverse osmosis system recovery rate to maximise process productivity and energy efficiency over a wide range of feed conditions.”
ACWA is a leading provider of innovative, sustainable process solutions for the air, water and wastewater sectors around the globe, providing design, build, operate and maintain capabilities.
The company’s water and waste water expertise comprehensively covers the filtration spectrum from conventional strainers and filtration systems to the most advanced reverse osmosis and ion exchange technologies.
Solutions include some of the world’s most prestigious and challenging projects including the 64,000 m3/day Palm Jumeirah desalination development in Dubai and the flagship 76,000 m3/day Al Ansab MBR plant in Oman, as well as high profile projects for international clients including Kellogg’s, Coca-Cola Enterprises, Center Parcs and many major UK and International water service companies and government bodies. The company is also very active in the current AMP programme in the UK. For more information, visit www.acwa.co.uk.
Reverse Osmosis Desalination
Reverse Osmosis uses hydraulic pressure and semi-permeable RO membranes to diffuse pure water (referred to as permeate) from seawater using osmotic pressure. The new solution at La Rosière on Jersey is designed to recover pure water at a rate of 45% from the seawater. The solutes in the seawater feed system are concentrated as a result of the process and are returned to the sea as concentrated brine.
Two streams each with 72 individual pressure vessels each containing 6 high pressure reverse osmosis membranes, 864 in total, will be deployed at La Rosière. See accompanying diagram for more information.
SOURCE: ACWA Services Ltd