The Ain Tsila gas condensate field is located in the Ilinzi basin in Algeria. The project is owned by Groupement Isarene, a joint venture of Petroceltic (56.625%), Enel (25%), and Sonatrach (18.375%).

The development plan for the field was approved in December 2012 and development works were commenced in 2014. The front-end engineering design phase began in 2015, while first gas is expected to be achieved in 2022.

The project is being developed with an estimated investment of $1.6bn.

Ain Tsila gas condensate field location

The Ain Tsila gas condensate field is situated in Blocks 228a and 229 in the Isarene concession in the Ilinizi basin, which is located approximately 1,100km south-east of Algiers, the capital city of Algeria.

The Isarene concession covers an area of 256,480ha, while the gas field covers an area of more than 100,000ha. It also hosts three other prospects namely Isarene Nord-Est, Isarne Nord-Ouest, and Hassi Tab Tab. The Amenas project lies to the east of the concession, while the Tin Fouye Tabankort field is located to the north.

Ain Tsila gas field discovery, appraisal, and reserves

The Ain Tsila field was discovered in 2009 by the AT-1 well and was the ninth biggest discovery in the world at that time.

Petroceltic drilled six delineation wells at the field to gather the data required for building the integrated reservoir model for the field and prepare the field development plan.

The Ain Tsila field is estimated to hold 2.1 trillion cubic feet of sales gas, 67 million barrels of condensate, and 108 million barrels of liquefied petroleum gas (LPG).

Ain Tsila gas field development details

The Ain Tsila field will be developed over a period of 30 years, during which 124 wells are planned to be drilled. A total of 24 wells will be drilled before the commencement of the gas production.

The planned facilities at the Ain Tsila gas condensate field include a single train gas processing plant equipped with water separation, and gas and condensate recovery equipment. It will also feature compression facilities, export pumps, and metering facilities.

The field is expected to achieve a plateau production rate of 355 million standard cubic feet per day (Mscfd) gross of wet gas over a 14-year period.

The development drilling campaign at the field was commenced in April 2016. The AT-13 well, the second well in the campaign, was drilled to a depth of 2,020m and encountered a 73m column of gas in sandstones of the Ordovician formation.

Gas transportation

The gas produced at the Ain Tsila field will be transported to the Algerian gas transmission network by a new 95km pipeline through a tie-in at the Tin Fouye Tabankort field.

Dedicated condensate and LPG export lines will be developed to transport condensate and liquids to the existing liquids transmission infrastructure.

Contractors involved

The FEED contract for the project was awarded to Chicago Bridge and Iron in September 2014, while Sinopec International Petroleum Service won the drilling rig contract in April 2015.

The $1bn engineering, procurement, and construction (EPC) contract for the project was awarded to Petrofac in March 2019. The scope of the contract includes commissioning, start-up, and performance testing of the field.

Salticom was contracted for the design, engineering, supply, and commissioning of radio system and communication towers.

Field Development Planning Partners, an independent consultancy based in the UK, carried out engineering studies and prepared the cost estimates and economics for the project. The company also provided assistance in preparing the scope of work for the FEED.