Chevron's San Ardo oil field in Southern California recovers more than 10,000 barrels of heavy oil each day. The oil extraction process generates large volumes of produced water that require treatment and management, typically disposed of by deep well injection. Chevron engaged Veolia's water treatment technology, engineering and operations experts to provide a new solution for sustainably treating the produced water. This would allow Chevron to minimize its water impact, while maximizing efficiency and significantly expanding production.
To achieve this, Veolia provided Engineer-Procure (EP) services and operates a produced water management facility at this oil field that features the first-ever installation of Veolia's OPUS® (Optimized Pretreatment and Unique Separation) technology. In this case, Chevron San Ardo's treated water is used in two ways - reused for steam generation, and released into aquifer recharge basins that replenish local water resources and allow Chevron to recover more oil. The reliable operations & maintenance of the plant is backed by a Veolia performance guarantee.
The process of extracting oil from the ground generates a volume of water that can range from 10 to 20 times the oil production rate. Historically, a portion of this water had been recycled and softened for reuse in steam generation, with the remainder going to local EPA class II injection wells for disposal. However the injection zone capacity is limited, which constrains full field development and daily production levels.
The raw produced water for this oil field is 200°F, and contains about 25 ppm free oil, 80 ppm TOC, 240 ppm silica, 26 ppm boron, 240 ppm hardness and 6,500 ppm Total Dissolved Solids (TDS). The project goal was to reduce the feed water TDS to less than 510 ppm and boron to less than 0.64 ppm for discharge, while achieving 75% water recovery across the treatment system and minimizing the volume of produced water requiring re-injection. For steam generation, the project goal was to reduce the feed water hardness to less than 2 ppm total hardness as CaCO3.
Veolia provided Chevron with the first produced water facility in the world to use its OPUS® technology, a multiple-treatment process that removes contaminants sufficiently to meet the established requirements for discharge. The technology and services provided by Veolia enables the plant's entire water cycle to be managed in a truly sustainable way, while simultaneously expanding oil production capacity.
Since the plant was commissioned in 2008, Veolia has operated and maintained (O&M) the facility for Chevron. Under its O&M contract, Veolia provides operations for the plant, which treats a combined 150,000 barrels of produced water daily, and oversees the facility's maintenance according to an established performance guarantee. Additionally, Veolia provides Chevron with on-site and off-site technical and engineering support to troubleshoot issues, maintain optimal operations, prevent failures and implement processes to help maximize oil production.
Veolia's innovative application of its OPUS® technology – groundbreaking for produced water management – has delivered exceptional value back to Chevron San Ardo. By developing a sustainable solution that allows up to 50,000 barrels per day of produced water for surface discharge and another 75,000 barrels per day for steam generation, Chevron is minimizing its environmental impact on water-stressed California by returning water to the aquifer recharge basins. And by avoiding deep well injection, Chevron has a long-term solution for managing produced water that limits its regulatory risk and supports expanded production activities.
Thanks to Veolia’s expert operations & maintenance staff who run the facility for Chevron, the produced water is consistently treated to levels that allow for surface discharge to replenish local water resources – a critically important factor for oil field operations and their social license to operate in California. With plant operations handled by Veolia and backed by a performance guarantee, Chevron can focus on its core operation of oil production.
By partnering with Veolia, Chevron San Ardo accomplished its objective of achieving a more circular, sustainable and reliable business operation.