July 5, 2010
A Whale, an airship and HORDs all part of Gulf spill clean-up
Rough sea states over the weekend mean that further testing will be needed to demonstrate the effectiveness of TMT Shipping Offshore's giant skimmer A Whale.
Meantime, the Coast Guard says that a Navy airship is en route to the Gulf for use as an aerial observation platform - and, at the other end of the clean-up scale from the 319,869 dwt A Whale, shipyards in Pensacola, Fla., and Bayou La Batre, Ala., are churning out towed "tarball retrieval devices" that are the brainchild of a super tanker master.
With results from an initial 48-hour test inconclusive in light of the rough sea states encountered, TMT Shipping Offshore says it will be undertaking an additional testing period to make operational and technological adjustments with A Whale, which is a newly developed tool to deal with oil slicks and which is being deployed for the first time.
The Navy's MZ-3A Airship is more economical to operate and can stay aloft for longer periods of time than helicopters or airplanes already in use. Because it travels slowly, it will be a helpful platform for aerial observers looking for marine mammals and other wildlife that may be in distress.
While the airship's primary mission is spotting and monitoring oil to support command and control of skimming operations, the locations of animals will also be passed to the Incident Commands so that vessels and crews can be dispatched to assist wildlife.
The airship will operate from a mooring three miles southeast of the Mobile Bay shoreline.
"The airship will operate relatively close to shore, primarily supporting skimmers to maximize their effectiveness," said U.S. Coast Guard Capt. Kevin Sareault, Deputy Area Commander for Aviation, Unified Area Command, Deepwater Horizon Oil Spill Response. "While different sensors are being considered, one of the primary means for locating oil will be by simple visual observation by the embarked aerial observers. The mission of overflights is to locate and direct surface assets to actionable oil - that is, oil that can be burned, dispersed or skimmed."
Just weeks after the first of a new kind of tarball retrieval device was successfully tested off the shores of Alabama, they've been given an acronym - HORD (Heavy Oil Recovery Device) - and gone into mass production. Up to 1,000 units are expected to be manufactured and put into service in the coming weeks.
The HORD has proven to be especially effective in collecting the thick, heavy oil that hampers traditional skimming methods. It is also able to cleanup the extremely light and difficult to remove sheen left on the water surface after skimming.
The brainchild of Capt. Gerry Matherne, the HORD exemplifies the adage "necessity is the mother of invention." Matherne, a supertanker captain and second generation seaman, who is under contract with BP, realized early on that something different was needed to quickly and effectively deal with the sticky, orange globs of oil (known as tarballs) floating just under the water's surface.
"Standard skimming methods work best on fresh oil on the water's surface. A lot of the oil we're dealing with on the Gulf has degraded, changing from a liquid state to a peanut butter-like consistency that floats on the surface and 12 to 18 inches below the surface," said Capt .Matherne. His answer is a single unit that acts as a filter, containment and disposal system rolled into one. A mesh bag held open by a 3-foot by 3-foot aluminum frame is dragged through the water by shrimp boats put into service as skimmers. The cage-like device scoops up surface oil and sheen, as well as the thick oil lurking beneath the surface of the water.
When the bags reach their two-ton capacity, they are switched out for empty ones, loaded onto smaller boats and transported to approved oil disposal units. The bags are later decontaminated and reused.
The total downtime for skimmers outfitted with HORDs is measured in minutes, compared to hours or days for a traditional skimmer that has to transport the captured oil to disposal units and wait to be unloaded, before returning to sea.
In addition to saving precious time, the HORD's simple design greatly improves a boat's maneuverability and ability to safely perform at faster speeds and in higher seas.