ONEOK Partners L.P. has started a two-year capital program to build a 16-in., 570-mile pipeline to transport natural-gas liquids (NGL) from the Central U.S. to the Texas Gulf Coast; reconfigure two existing pipelines to transport unfractionated NGL or NGL purity products; and build a new, 75,000-barrels/day NGL fractionator in Texas. The project is estimated at $910 million to $1.2 billion.

Tulsa-based ONEOK Partners owns and operates an NGL system in the Mid-Continent and Gulf Coast, including fractionators and storage in Mont Belvieu, Texas; Bushton, Conway, and Hutchinson, Kan.; and Medford, Okla.

Most natural gas produced at the wellhead contains a mixture of natural gas liquids components (e.g., ethane, propane, iso-butane, normal butane and natural gasoline), and these must be removed in processing plants, using fractionation plants. Fractionation separates natural gas into component parts for transport and treatment. ONEOK’s operations gather, fractionate, treat, and store unfractionated NGL products produced from basins in Oklahoma, Kansas, Wyoming, Colorado and Texas.

"Building this new pipeline and reconfiguring our existing Sterling I and II pipelines give us the flexibility to transport and optimize the flow of unfractionated or purity NGLs through all three pipelines," according to the company’s COO Terry K. Spencer said. "These pipeline projects, along with our previously announced Arbuckle Pipeline and Sterling I Pipeline expansions, further enhance our ability to transport NGLs – either unfractionated or purity products – to Gulf Coast markets."

The new pipeline will be called Sterling III and will have an initial capacity to transport 193,000 barrels/day of either unfractionated NGLs or NGL purity products from Medford, Okla., to Mont Belvieu, Tex., for storage and fractionation facilities. It will double ONEOK’s current pipeline capacity (Sterling I and II) between Medford and Mont Belvieu.

The Sterling I and II pipelines, which distribute NGL purity products between the Mid-Continent and Gulf Coast markets, will be reconfigured to transport either unfractionated NGLs or NGL purity products.

ONEOK also owns interstate pipelines that distribute NGL between Conway and Mont Belvieu, and transport NGL and refined petroleum products from its Kansas and Oklahoma operations into the Midwest.

The third part of the capital program calls for building a new, 125,000-barrels/day fractionator at Mount Belvieu, Tex., to supplement a majority owned, 160,000-barrels/day fractionator there. Its initial 75,000 barrels/day capacity may be expanded to 125,000 barrels/day to accommodate additional NGL volumes as they are added to the currently expanding pipeline system.

"These projects will accommodate the growing NGL supplies in the Mid-Continent and elsewhere and help to alleviate the infrastructure constraints between the Mid-Continent and Gulf Coast markets, while meeting the requirements of natural gas processors and NGL customers," stated Spencer.