Williams Companies Inc. said Wednesday that it has signed a new long-term gas processing agreement with an unnamed producer in the Canadian oil sands.

The Tulsa, Okla.-based company said that under this agreement, it will extract, transport, fractionate, own and market the natural gas liquids and olefins it gathers from the producer’s site in Alberta, Canada.

Williams anticipates recovering roughly 12,000 barrels per day by 2015 and 15,000 by 2018. It did not place a financial value on the deal.

The company will process some of the natural gas liquid and olefins mixture into other products, such as propane, that can be sold.

Williams Energy Canada president David Chappell said the agreement builds on the company’s processing, distribution and storage infrastructure in Canada.

To support the deal, Williams said it plans to build a new liquids extraction plant and supporting facilities at the site. It also plans to build an extension of one of its Boreal pipeline to transport the natural liquid gas mixture to its processing facility outside of Edmonton.

Williams is an energy infrastructure company with thousands of miles of pipeline in North America.

Its shares fell 76 cents to end Wednesday trading at $33.98.