By OGJ editors
HOUSTON, Sept. 22 -- The American Bureau of Shipping has issued full-class design approval for CNG carriers to Sea NG Corp., Calgary. The approval is the first granted to CNG carriers, ABS said.
Sea NG's proprietary Coselle system uses small-diameter high-strength steel pipe coiled into a carousel to store the high-pressure gas. Each Coselle will comprise about 10 miles of 6-in. pipe used for storing and transporting CNG.
Sea NG is expected to let contracts for construction of three Coselle CNG carriers later this year. These first vessels, which will carry the notation "A1 CNG Carrier," will be designed to transport gas 200-2,000 miles. They are intended to service projects in the Caribbean or Mediterranean seas.
The vessels will be 120 m long and have the capacity to carry 50 MMscf of gas in 16 Coselles (160 miles of pipe). 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 and also a proprietary high- and low-pressure manifold system for efficient loading and unloading.
ABS Project Manager Harish Patel said, "This vessel design review and approval was undertaken using a risk-based design approach."
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.