First CNG Carrier ready for construction to ABS Class
Posted: 25 September 2006
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ABS has given full design approval for the class of the compressed natural gas (CNG) carrier designed and developed by Canadian-based Sea NG Corporation. Full approval follows the earlier Approval in Principle (AIP) issued by ABS for the Sea NG design in 1997 and is the first full class approval for a CNG carrier issued by the Bureau.
Sea NG is expected to award construction of three Coselle CNG carriers later this year. These first vessels are intended to service projects in the Caribbean or Mediterranean Seas .
"We are pleased to bring innovation to the marine gas transportation market by offering a new ship-based gas delivery system that is safe, reliable and economic,"said Dave Stenning, President & CEO of Sea NG.
 The vessels' design has been approved to the standards established in the ABS Guide for Vessels Intended to Carry Compressed Natural Gases in Bulk as well as applicable parts of the ABS Steel Vessel Rules. Once constructed and accepted into class by ABS the vessels will carry the notation "A1 CNG Carrier".
Sea NG uses its proprietary Coselle system for storing and transporting CNG. This patented system uses small diameter high-strength steel pipe coiled into a carousel to store the high-pressure natural gas. The carousel provides support and protection for the pipe and facilitates transport and stacking of the Coselles within the ship. Each Coselle will comprise approximately 10 miles of 6-inch diameter pipe.
These Sea NG vessels will be 120m in length and have the capacity to carry 50 million standard cubic feet of gas (MMSCF) in 16 Coselles (160 miles of pipe in total). The 16 Coselles are arranged in four stacks of four high in a fully enclosed and inerted cargo house on the weather deck. The vessels will feature a dual fuel propulsion system with bow thruster.
According to ABS Project Manager Harish Patel, the ABS review, which led to full class approval of the design, included: a prototype test program of the Coselle containment system, review of the structural and marine systems drawings, and extensive risk analysis. "This vessel design review and approval was undertaken using a risk-based design approach," says Patel.
This included a series of risk assessment studies including: HAZID, HAZOP, gas dispersion and explosion models, fire, flaring and heat radiation analysis, a jetting study, escape and evacuation studies and inspectability analysis.
The Sea NG vessels also feature a proprietary high and low pressure manifold system for efficient loading and unloading of the natural gas.
Sea NG offers a complete solution to move gas to market including the technology, the engineering, the ships, the onshore compression facilities and overall project management. |
