Pentair was selected to supply its X-Flow ultrafiltration (UF) membranes as pretreatment for the Kraken FPSO sulphate removal membranes in one of the largest subsea heavy-oil field projects under development in the UK section of the North Sea.

The Kraken field will be developed with an FPSO from Bumi Armada, a Malaysia-based international offshore oilfield services provider that is a global FPSO player and among the top owners and operators of OSVs in Asia. The Kraken field could have reserves of 137 million barrels of heavy oil, with an estimated field life of 25 years. At its peak, it is expected to produce more than 50,000bpd. The FPSO is designed to process up to 460,000bpd and has a storage capacity of up to 80,000bpd of oil and 20 million standard cubic feet of gas. Seawater injection is at a maximum rate of 275,000bpd.

"This order confirms again the suitability of Pentair’s X-Flow brand of UF membranes for offshore seawater treatment and we are committed to support the important water treatment needs of our oilfield customers."

An FPSO unit is a floating vessel used by the offshore oil and gas industry for the processing of hydrocarbons and storage of oil. FPSOs are preferred in frontier offshore regions because they are easy to install and do not require a local pipeline infrastructure to export oil.

Using the X-Flow UF membranes as the pretreatment solution rather than conventional pretreatment options, such as multimedia filtration followed by disposable cartridge filters, provides lower life-cycle costs, a smaller footprint and lower installed weight, as well as improved performance of the downstream sulphate removal membranes.

Pentair oil and gas business development manager Eric Leegwater said: "This order confirms again the suitability of Pentair’s X-Flow brand of UF membranes for offshore seawater treatment and we are committed to support the important water treatment needs of our oilfield customers."

Pentair’s history of as a market leader in water process engineering and products led to being awarded this project. The X-Flow brand is the global low-pressure membrane market leader. The group provides expertise and experience in water purification, ranging from producing potable (drinking) water to treating process and wastewater. Within the oil and gas industry, X-Flow membranes are used in such applications as seawater injection, produced water re-injection, silica removal in boiler feed water for SAGD, low-salinity water injection for IOR/EOR/CEOR, reuse of oily wastewater treatment on refineries and fresh potable water makers.