Purifying produced water

May 15, 2003, 11:00 CEST

A 50 per cent interest in the Stavanger-based company CTour Process Systems has been acquired by Statoil. This firm specialises in technology for purifying water produced in oil recovery.

Statoil's investment company Offtech Invest, in Technology's industrial development unit, is responsible for the deal.

CTour Process Systems has taken over the patent rights and markets the CTour technology. This technology has proved effective in purifying large volumes of polluted reservoir water. Two pilot projects have been carried out on Statoil's Statfjord B platform in the North Sea.

"The tests show that cleansing with CTour can reduce emissions of hydrocarbons in produced water from the Statfjord field by 70 per cent," says Eivind Aarebrot, special adviser in Statoil's process technology sector.

Statoil will now build a full-scale facility on the Statfjord C platform.

The technology has been developed by Rogaland Research in cooperation with Statoil, among others.

The method uses the platform's own condensate to cleanse the produced water of environmentally-harmful hydrocarbons. The condensate washes the hydrocarbons out of the water.

"This technology could become very important for Statoil," Mr Aarebrot reports. "It is an alternative to injecting the produced water underground and it is also considerably cheaper."

The method could save the oil companies substantial costs and it is an important step in the work to develop new environmentally-friendly solutions. Statoil is on the right track to meeting the authorities' requirements for zero harmful emissions from the oil and gas fields by 2005.