|
UPDATE: Guide for Building and Classing Offshore LNG Terminals
Now Includes New Standards for Gravity-Based LNG Terminals
|
This concept for a gravity-based concrete LNG
storage and offloading terminal was developed
by Sapiem. The primary containment for the rectangular
storage tanks will incorporate Technigaz SN membrane
technology using waffles. Vessel capacity is approximately
250,000 cubic meters. The unit will have a liquefaction
plant to liquefy the boil-off gas. ABS has given
approval in principle to this unit.
|
|
|
and Classing Offshore LNG Terminals with the release of new standards for gravity-based structures. Since releasing the Guidance Notes for floating terminals in May 2002, ABS has been working with several operators who are developing new design concepts and technologies to bring stranded remote and deepwater gas reserves to market in a safe and economical manner.
According to Todd Grove, Director of Offshore Project Development, gravity-based structures are an alternative to floating designs when a shallow water solution to storing LNG offshore is needed. It also offers advantages over floating units when it comes to relative motion. "With a floating terminal and an LNG tanker, you’ve got the relative motion of the two vessels to deal with," he says. "In the case of a concrete or steel gravity-based structure, the terminal is fixed to the seabed, so only the motion of the ship is a factor."
|
.William J. Sember, ABS Vice President, Offshore Development notes that ABS received many requests for gravity-based criteria in the weeks after the release of the Guide for floating terminals. "Gravity-based structures are a viable option for many of the proposed terminal locations," says Sember. "There was a very clear demand for these additional standards from designers and potential operators of bottom sitting structures."
From the concept stage to the granting of "class approval in principal," ABS has been assisting them in identifying appropriate safety criteria and structural standards for these new offshore facilities. The new section that addresses gravity-based structures includes criteria for both steel and concrete terminals. Grove points out that most of the technology for creating gravity-based structures exists already, but the challenge is to put that technology to work in a new application. "For example, tank storage in a gravity-based structure is not going to be significantly different," says Grove, "although the installation of very large tanks holding in excess of 200,000 cubic meters of LNG will affect both floating and gravity-based structures."
|
