Ichthys Field, Browse Basin, Timor Sea, Australia

The Ichthys field is situated on block WA-285-P in the Browse Basin, Timor Sea, Western Australia. This gas and condensate field lies at a water depth of 280m.

Tokyo-based Inpex is the operator of the Ichthys field with a 76% interest. The remaining 24% interest is held by Total E&P Australia.

The field's development is expected to require an investment of $20bn. The final investment decision will come in the fourth quarter of 2011. First gas from the field is expected to be achieved in late 2016. At its peak, the field will produce eight million tonnes per year of LNG, 1.6 million tonnes per year of LPG and 100,000 barrels per day of condensate.

A new LNG facility at Blaydin Point, Australia, will be built as part of the project. The plant will include two LNG trains with a capacity of 8.4 million tonnes per year, processing plants, storage tanks, a jetty and other utilities. Construction of the new plant is expected to begin at the end of 2011.

Discovery of Ichthys

The Ichthys field was discovered in 1980 by Woodside Petroleum with the drilling of the Brewster 1A exploration well. In 1998, Inpex acquired the rights to the field and began exploration activities.

Three additional exploration wells were drilled at the field in 2000. Five appraisal wells were drilled between June 2003 and February 2004. The field was declared commercially viable in March 2009.

Geology and reserves

Gas is contained in two reservoirs of the Brewster and Plover formation. Ichthys is estimated to contain 530 million barrels of condensate and 12.8 trillion cubic feet of natural gas. The life of field is estimated to be more than 40 years.

Ichthys field development

The Ichthys field will be developed using a Central Processing Facility (CPF). A floating production storage and offloading (FPSO) facility will be installed nearby to treat and store condensate. Other facilities will include umbilicals, risers and flow lines.

The development will involve drilling of about 30 subsea wells into the Brewster reservoir and another 20 into the Plover reservoir.

The semi-submersible CPF will be 100m high and 100m wide. It will be moored in place by 24-32 mooring systems and suction piles, and will collect gas from various production wells and undertake initial processing. The CPF will accommodate up to 150 personnel.

FPSO

Liquids processed at the CPF will be sent to the FPSO through a turret. The FPSO will be able to store 1.2 million barrels of condensate. It will feature a 150-person accommodating facility.

Subsea system

The subsea system at the Ichthys field will include subsea trees, manifolds, flowlines and umbilicals.

Wells drilled into the field will be connected to the manifolds.

Gas recovered from the wells will be collected at the manifolds and sent to the CPF through the flowlines.

Processing systems

The produced gas will be sent to the CPF where condensate, water and other liquids will be separated. The processed gas will be then sent from the CPF to the new LNG facility.

The condensate separated from the gas will be sent to the FPSO from where it will be transferred to tankers for delivery to markets.

Pipeline

An 850km-long pipeline will carry the produced gas from the CPF to the new LNG facility. The pipeline will have a diameter of 42in.

Contracts for Ichthys

In April 2009, AMEC was awarded the front end engineering design (FEED) contract for the Ichthys field. AMEC will carry out the FEED studies for the offshore facilities and an export pipeline.

AMEC subcontracted Aker Solutions to carry out the FEED studies for the CPF and the FPSO.

In May 2009, John Wood Group's subsidiary JP Kenny won the contract for carrying out FEED studies for the umbilicals, risers and flowlines for the field. Another subsidiary of John Wood Group, MSC, will be responsible for designing the dynamic riser system for the field.

Atteris provided design services for the shore crossing of the export pipeline.

RPS Group and URS Australia were involved in carrying out the environmental impact assessment studies for the field.

Fugro Survey was contracted to provide geophysical survey services for the offshore facilities, subsea pipeline and loading and handling facilities.

MSi Kenny was involved in the pre and post-FEED stages of the project. The company also carried out thermal/hydraulic analysis of the subsea system and the necessary tie-backs.