Chevron San Ardo Water Reclamation Facility, California

What is it? An expansion project to increase the production of soft water at Chevron's oil production field in San Ardo, California from 10,000 barrels per day (1,636m3/d) to 70,000 bpd (11,456m3/d). The project also includes the addition of an advanced treated water process, which will be capable of producing 50,000 bpd (8,183m3/d) of treated water for discharge. The facility was completed in June 2008.

Who is involved? N.A Water Systems (part of Veolia) will design and procure the major process equipment for the water treatment facilities, as well as manage construction and train operators and maintenance personnel. Veolia Water North America will operate and maintain the water treatment facilities.

Why is it shortlisted?

• The Chevron plant features the first ever large-scale use of reverse osmosis membrane technology for produced water treatment in the oil and gas industry. It employs the groundbreaking OPUS™ (Optimized Pretreatment and Unique Separation) treatment process developed by Chevron and N.A. Systems, which treats oilfield produced water to sufficient standards for surface discharge.

• The presence of hydrocarbons makes produced water treatment particularly tricky. The revolutionary system devised by Chevron and N.A. Systems employs a chain of treatment processes, including heat exchange, degasification, chemical softening, media filtration and ion exchange softening, before putting the water through a double-pass RO system at a high pH.

• The process of extracting oil from the ground generates a volume of water up to ten times that of the oil produced. The trade-off for treating this produced water is that it can then be reused to produce steam for injection into the ground to assist in raising heavy oil to the surface. Chevron and Veolia's technological breakthrough enables the plant's entire water cycle to be managed in a truly sustainable way, whilst simultaneously expanding production capacity.