Nitrogen EOR pilot planned for Spain

Oct. 1, 2010
Leni Gas & Oil PLC (LGO) plans to start a pilot nitrogen enhanced oil recovery project on Ayoluengo's upper Jurassic west flank reservoirs in Spain's Burgos region.

By OGJ editors
HOUSTON, Oct. 1
-- Leni Gas & Oil PLC (LGO) plans to start a pilot nitrogen enhanced oil recovery project on Ayoluengo's upper Jurassic west flank reservoirs in Spain's Burgos region.

The company expects to start construction of the facilities at yearend and commence injection in first-quarter 2011.

Ayoluengo's upper Jurassic west flank reservoirs contain 27.31 million bbl of OOIP and have a cumulative production of only 1.4 million bbl of 37° gravity oil, according to LGO. The west flank reservoirs currently do not have any producing wells.

The company explained that it selected nitrogen for the EOR project because liquefied nitrogen is easier to produce and transport than carbon dioxide and does not require water for reservoir pressurization or waterflooding. Also because nitrogen is inert, it is not corrosive and can function for both reservoir repressurization and to support water or polymer floods.

The current Ayoluengo production is from the east flank upper Jurassic reservoirs that contain 79.39 million bbl of OOIP and have a 21% recovery to date. LGO currently is undertaking exploitation projects to increase the productivity and drainage radius of all east flank wells.

Chevron Corp. discovered the field in 1964 and sold it share of the field to Repsol-YPF SA in the 1990s. LGO currently owns a 100% interest in the field.

LGO will obtain the nitrogen and equipment for the pilot from Praxair Espana SL upon signing a definitive agreement. The definitive agreement, if signed, would also include the option for Praxair to participate on all other assets within LGO's 550 sq km petroleum production and exploration acreage in northern Spain.

Under the proposed terms of the definitive agreement, LGO would manage the project supported by Praxair and the company's key engineering service providers. Praxair would support the design activities, supply the nitrogen, and make provisions for nitrogen storage tanks and the equipment for nitrogen delivery.