Northeast US offshore LNG terminal undergoes commissioning

May 6, 2009
After more than 3 months' delay, the newest US offshore LNG terminal delivered the commissioning cargo earlier this week for Excelerate Energy's Northeast Gateway deepwater port, 13 miles off Boston.

Warren R. True
Chief Technology Editor-LNG/Gas Processing

HOUSTON, May 6 -- After more than 3 months' delay, the newest US offshore LNG terminal delivered the commissioning cargo earlier this week for Excelerate Energy LLC's Northeast Gateway deepwater port, about 13 miles off Boston. Delivery was by the company's newest Energy Bridge regasification vessel Explorer.

The company said Explorer had arrived in mid-January to complete downstream facility commissioning in conjunction with Algonquin Gas Transmission followed by routine delivery of natural gas into local markets.

During discharge, however, methane hydrates formed in the pipeline connecting Northeast Gateway to the Hubline pipeline, blocking it and forcing suspension in the delivery. Excelerate explained that hydrate formations can occur when moisture is condensed in natural gas under high pressure. This moisture, said the company, was residue from the pipeline's construction.

Efforts to remove the hydrate blockage finally succeeded in mid-April, allowing Explorer to reconnect to the buoy and complete delivery of its cargo. This full cargo discharge effectively dried the pipeline and removed all residual moisture, according to Excelerate, thereby preventing formation of hydrates during future deliveries.

Excelerate Chief Executive Officer Rob Bryngelson said completion of the discharge "took longer than anyone had expected." Based near Houston in the Woodlands, Excelerate is an LNG importer and marketer.

Contact Warren R. True at [email protected].