Colony Shale Oil Project

Colony Shale Oil Project was an oil shale development project at the Piceance Basin near Parachute Creek, Colorado. The project consisted of an oil shale mine and pilot-scale shale oil plant, which used the TOSCO II retorting technology, developed by Tosco Corporation. Over time the project was developed by a consortium of different companies until it was terminated by Exxon on 2 May 1982 a day which is known amongst locals as "Black Sunday".[1][2][3]

History

The project started in 1964 when Tosco, Standard Oil of Ohio, and Cleveland Cliffs Iron Company formed the Colony Development joint venture.[4] The aim of the newly formed joint venture was to develop the Colony Oil Shale Project and to commercialize the TOSCO II technology. Starting in 1965 the consortium operated a shale oil pilot plant and in 1968 the Colony Development started preparations to build a commercial-scale plant.[5]

In 1969 Atlantic Richfield Company joined the project acquiring part of Tosco's stake.[5][6] However the commercial project was delayed by economic uncertainties and then resurrected in the 1970s after the Arab oil embargo. In 1972 the consortium stopped the pilot plant and the development of the commercial plant was suspended in November 1974 when more detailed economic studies indicated a more than three times higher cost than previously anticipated.[4]

Location

The Colony Development's property located in the southern edge of the Piceance Basin in northwestern Colorado, approximately 200 mi west of Denver.[9] It located next to the Union Shale Oil property, developed by Unocal Corporation.[5]

Technical description

The pilot stage of the project consisted of underground room-and-pillar type oil shale mine and aboveground shale oil pilot plant with input capacity of 1,000 ton of oil shale per day which used TOSCO II retort a horizontal rotating kiln-type retort classified as a hot recycled solids technology.[5][12] Mining was conducted in a 60 ft-thick portion of the Mahogany Zone in the Parachute Creek Member of the Green River Formation at depths of 860 ft and 600 ft by a one-bench system. Pillar dimensions were 58 ft by 58 ft and rooms were 55 ft wide.[9]

The planned commercial scale plant was to contain six TOSCO II retorts with total input capacity of 66,000 ton of oil shale per day. The proposed plant was to produce about 46000 oilbbl of shale oil per day.[5] The project was also to consists of shale oil upgrading plant for hydrogen treating to remove nitrogen and sulfur compounds. This plant was scheduled to produce about 17 Moilbbl of premium petroleum products, 52,000 long ton of sulfur, and 41,000 long tons of ammonia per year.

See also

• History of the oil shale industry in the United States
• Rio Blanco Oil Shale Company