Australia's Subsea Mega-Pipeline Complete

Castorone's pipelay operation

By Wendy Laursen 2015-11-06 09:13:08

Australia’s Ichthys LNG offshore pipeline has been successfully completed by Inpex. The 890-kilometer (550 mile), 42-inch diameter gas export pipeline is the longest subsea pipeline in the southern hemisphere and the third longest subsea pipeline in the world. 

Construction began in June 2014, and the pipelay was carried out by Saipem’s Semac-1 barge and the Castorone pipelay vessel.

The Ichthys LNG project is a large-scale LNG project by global standards and is expected to be operational over a period of 40 years. The project involves LNG lifted from the Ichthys gas-condensate field 200 kilometers offshore from Western Australia. The export pipeline will deliver gas from the Ichthys gas field to the onshore facilities at Bladin Point near Darwin, Australia, for processing.

The project includes some of the world’s biggest and most advanced offshore facilities, massive onshore processing facilities near Darwin and the 890 kilometer gas export pipeline to unite them. Each of these three components is itself a mega-project and work is progressing for all, with production scheduled for the end of 2016.

The field has the capacity to produce approximately 8.9 million tons of LNG and approximately 1.6 million tons of LPG per year, along with approximately 100,000 barrels of condensate per day at peak. 

“Completion of the offshore pipelay marks a significant milestone for the project,” Managing Director Ichthys Project Louis Bon said. “It means we are one step closer to physically connecting our onshore plant near Darwin to the Ichthys Field where our offshore facilities will be permanently moored for the 40-year life of the Project.”

The Ichthys LNG Project is a project led by Inpex (Operator, participating interest: 62.245 percent) alongside Total (30 percent), CPC Corporation Taiwan (2.625 percent), Tokyo Gas (1.575 percent), Osaka Gas (1.2 percent), Kansai Electric (1.2 percent), Chubu Electric Power (0.735 percent) and Toho Gas (0.42 percent).

Inpex will now start preparing the pipeline for operational start-up.

The Ichthys central processing facility was floated out from the offshore floating dock at the Samsung Heavy Industries shipyard in Geoje, South Korea, in September.

Currently under construction in South Korea, the CPF and FPSO, once completed, will be towed to the Ichthys field in 2016 where they will be moored by 40,000 tons of chain secured to about 20,000 tons of foundation piles.

The onshore processing facilities near Darwin will cool gas from the pipeline and transform it into liquid to reduce its volume for transport. Onshore facilities will include: two LNG trains, LPG and condensate plants, product storage tanks, administration facilities, utilities and a jetty. A peak workforce of about 8,000 onsite on any given day is needed to complete the onshore facilities at Bladin Point, which are currently under construction.

The lchthys LNG Project will require three LNG carriers and one LPG carrier to export product from Darwin Harbour each week as well as one or two condensate carriers each month.