Feds issuing draft enviro review on Delfin LNG export project

The U.S. Maritime Administration (MARAD), in cooperation with the U.S. Coast Guard (USCG) and the Federal Energy Regulatory Commission (FERC), will in the July 15 Federal Register announce the availability of the Draft Environmental Impact Statement (DEIS) for the Delfin LNG LLC deepwater port license application for the exportation of natural gas. 

The proposed Delfin LNG deepwater port would be located in federal waters within the Outer Continental Shelf (OCS), about 37.4 to 40.8 nautical miles off the coast of Cameron Parish, Louisiana. The proposed Delfin LNG deepwater port incorporates onshore components, which are subject to FERC jurisdiction.

Publication of this July 15 notice will begin a 45-day comment period, requests public participation in the environmental impact review process, provides information on how to participate in the process and announces informational open houses and public meetings in Cameron, Louisiana and Beaumont, Texas.

On May 8, 2015, as supplemented on June 19, 2015, MARAD and USCG received a license application from Delfin LNG for all federal authorizations required for a license to own, construct and operate a deepwater port for the export of natural gas. Delfin LNG is proposing to construct, own, operate and eventually decommission a deepwater port in the Gulf of Mexico to liquefy domestically-sourced natural gas for export. Exports are proposed to both Free Trade Agreement nations and non-Free Trade Agreement nations, in accordance with Department of Energy export license approvals.

The proposed Delfin LNG deepwater port has both onshore and offshore components. The Delfin LNG deepwater port would consist of four semi-permanently moored Floating Liquefied Natural Gas Vessels (FLNGVs). The deepwater port would reuse and repurpose two existing offshore natural gas pipelines; the former U-T Operating System (UTOS) pipeline and the High Island Operating System (HIOS) pipeline. Four new 30-inch diameter pipeline laterals, each approximately 6,400 feet in length, connecting the HIOS pipeline to each of the FLNGVs, would be constructed.

In addition, a 700-foot 42-inch diameter new pipeline would be constructed to bypass a platform at WC lease block 167 (WC 167) and connect the UTOS and HIOS pipelines. Feed gas would be supplied through the new pipeline laterals to each of the FLNGVs where it would be super-cooled to produce LNG. The LNG would be stored onboard the FLNGVs and transferred via ship-to-ship transfer to properly certified LNG tankers. Each of the FLNGVs would be semipermanently moored to four new weather-vaning tower yoke mooring systems (TYMS).

The onshore components of the Delfin LNG deepwater port will consist of constructing and operating a new natural gas compressor station, gas supply header and a metering station at an existing gas facility. The proposal would require:

  • reactivation of approximately 1.1 miles of existing 42-inch pipeline, formerly owned by UTOS, which runs from Transcontinental Gas Pipeline Company Station No. 44 (Transco Station 44) to the mean highwater mark along the Cameron Parish Coast;
  • installation of 120,000 horsepower of new compression;
  • construction of 0.25 miles of 42-inch pipeline to connect the former UTOS line to the new meter station; and
  • construction of 0.6 miles of twin 30-inch pipelines between Transco Station 44 and the new compressor station.

Onshore pipeline quality natural gas from the interstate grid would be sent to the existing, but currently idle, 42-inch UTOS pipeline. The gas transported through the UTOS pipeline would then bypass the existing manifold platform located at WC 167 via a newly installed pipeline segment, 700 feet in length, connecting to the existing 42- inch HIOS pipeline. The bypass of the WC 167 platform would be trenched so that the top of the pipe is a minimum of 3 feet below the seafloor. From the bypass, the feed gas would then be transported further offshore using the HIOS pipeline portion leased by Delfin LNG between WC 167 and High Island A264.

The existing UTOS and HIOS pipelines transect OCS Lease Blocks WC 314, 318, 319, 327, and 335, and would transport feed gas from onshore to offshore (one-directional flow). Delfin LNG proposes to install four new lateral pipelines along the HIOS pipeline, starting approximately 16.0 nautical miles south of the WC 167 platform. Each subsea lateral pipeline would be 30 inches in diameter and approximately 6,400 feet in length, extending from the HIOS pipeline to the Delfin LNG deepwater port. The FLNGVs would receive pipeline quality natural gas via the laterals and TYMS where it would be cooled sufficiently to completely condense the gas and produce LNG.

The produced LNG would be stored in International Maritime Organization (IMO) type B, prismatic, independent LNG storage tanks aboard each of the FLNGVs. Each vessel would have a total LNG storage capacity of 210,000 cubic meters (m3 ). The offloading system would be capable of accommodating standard LNG tankers with nominal cargo capacities up to 170,000 m3.

Approximately 31 LNG tankers are expected to visit each of the four FLNGVs per year for a total of up to 124 cargo transfer operations per year. The FLNGVs would be self-propelled vessels and have the ability to disconnect from the TYMS and set sail to avoid hurricanes or to facilitate required inspections, maintenance and repairs.

In the nominal design case, based on an estimated availability of 92% and allowance for consumption of feed gas during the liquefaction process, each of the four FLNGVs would produce approximately 146 billion standard cubic feet per year (Bscf/y) of gas (approximately 3.0 million metric tonnes per annum [MMtpa]) for export in the form of LNG. Together, the four FLNGVs are designed to have the capability to export 585 Bscf/y of gas (approximately 12.0 MMtpa).

As detailed engineering and equipment specification advances during the design process and operating efficiencies are gained post-commissioning, the liquefaction process could perform better than this nominal design case. It is anticipated that LNG output could improve to as much as 657.5 Bscf/y in the optimized design case (approximately 13.2 MMtpa) which is the amount Delfin LNG is requesting authorization to export.

The proposed Delfin LNG deepwater port would take a modular implementation approach to allow for early market entry and accommodate market shifts. Offshore construction activities are proposed to begin at the end of first quarter of 2018 and would be completed in four stages, with each stage corresponding to the commissioning and operation of an FLNGV. The anticipated commissioning of FLNGV 1 is the third quarter of 2019 with start-up of commercial operation of FLNGV 1 by the end of 2019. It is anticipated that FLNGVs 2 through 4 would be commissioned 12 months apart. Following this schedule and barring unforeseen events, the Delfin deepwater port would be completed and all four FLNGVs would be fully operational by the summer of 2022.

On May 8, 2015, Delfin LNG filed its original application with FERC requesting authorizations for the onshore components of the proposed deepwater port terminal including authorization to use the existing pipeline infrastructure, which includes leasing a segment of pipeline from HIOS extending from the terminus of the UTOS pipeline offshore.

About Barry Cassell 20414 Articles
Barry Cassell is Chief Analyst for GenerationHub covering coal and emission controls issues, projects and policy. He has covered the coal and power generation industry for more than 24 years, beginning in November 2011 at GenerationHub and prior to that as editor of SNL Energy’s Coal Report. He was formerly with Coal Outlook for 15 years as the publication’s editor and contributing writer, and prior to that he was editor of Coal & Synfuels Technology and associate editor of The Energy Report. He has a bachelor’s degree from Central Michigan University.