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Vela’s Ballast System Gets Patent
The United States Patents and Trademark Office (USPTO) recently granted a patent to Saudi Aramco for the invention "Ballast Exchange System for Marine Vessels."
The inventor, Capt. Thomas Scott of Vela International, describes the invention as a method for replacing existing ballast water in the ballast tanks of a ship while the ship is underway. The method uses a seawater inlet port in the bow of the ship that admits water when the ship is moving, to produce a pressure that is greater than the pressure of the ballast water that is to be replaced.
The seawater from the inlet port is directed into the bottom of the ballast tanks where it rises to displace the existing water from outlet ports in the top of the ballast tanks.
"According to existing environmental regulations," Scott said, "all carried ballast water must be chemically treated before being discharged to the sea."
The value of the patent, granted July 27, rests in its potential to be a less-expensive method compared with other technologies and chemical treatment required by the International Marine Organization's (IMO's) Ballast Water Management regulations.
The administrator of Intellectual Assets Management, Dr. Mohammed A. Alansari, said that once IMO approval is granted to implement it, the new design will:
- Address an environmental issue.
- Use existing ballast systems with no added energy to operate.
- Require no expensive technologies to buy, install or maintain.
- Be designed to operate without crew monitoring and require little maintenance.
Vela International also won the Dubai International Maritime Award for innovation in shipping.
We have below an extract of the paper presented by Captain Thomas Scott of Vela International explaining the uniqueness of this invention.
Invasive species are a problem of increasing importance to the world. Whether it’s Crows in Bahrain, Brown Snakes in Guam or Zebra Mussels in Canada, the cost of non indigenous species establishing a niche in an ecosystem and destroying other species and the industries they support is a burgeoning problem world wide. United Nations studies have shown that billions of dollars are spent each year to combat the negative effects invasive species have on the world’s fishing industries, marine structures and most importantly public health. To remedy the problem, the International Maritime Organization (IMO) has sponsored a Ballast Water Management Convention that has proposed regulations requiring all ships to institute Ballast Water Management (BWM) plans and that will eventually require treatment facilities on all ships by 2016 or fit alternative technology by that date.
This paper describes patented technology, developed by Vela that will achieve all the requirements set by the IMO for acceptance as an alternative to treatments. The reason Vela is developing this technology is that all current treatment technologies are very expensive to fit and operate. They are simply too expensive and entirely impractical for VLCC sized tankers. Current treatment technologies all would require the installation of sensitive equipment costing in excess of $1,000,000 to retro-fit on a VLCC sized ship, approximately $100,000 per voyage to operate and add a week to the discharge time of every VLCC. In addition there would be the costs for maintenance and training of the ship’s crew to operate the treatment system.
In comparison, Vela’s technology attaches to the existing ballast system, will cost approximately $500,000 to retrofit on a VLCC, requires no extra cost or special skills to operate, and achieves all the control requirements of the IMO’s proposed Ballast Water Management regulations.
Vela’s Design - AUBALEX - An Alternative to “TREATMENT” addresses all the concerns of the Ballast Water Management Convention regulations and will be a more economical solution in comparison with the “TREATMENT” technologies that are required starting in 2014 for most large tankers and container ships.
Bio-Regions are fairly large, typically 500 miles across, although their shape sometimes makes this distance shorter. Because the AUBALEX system provides for a continuous exchange of water, the transportation of any harmful marine species or risk species (as defined by the UNDP Globallast program) is eliminated because these are expelled with the ballast water within the same Bio Region and never more than 500 miles from its initial entry into the AUBALEX system.
WHAT AUBALEX LOOKS LIKE
AUBALEX attaches directly to the ship’s existing ballast system at the forward end of the ballast pipeline. It consists of a Central Pipeline System (CPS - See Figure 1 inset circle A), and a Bow Access Opening (See Figure 1 see inset circle B) to allow water to enter at the bow’s stem.
The water enters the tank in the same way as conventional ballast systems but is discharged overboard at the tank top via sluice gates or overflow pipes as per Figure 2. at the shear strake or at the tank top
 Note that the existing or typical ballast system is not changed and that pressure created by the ship’s motion through the water is what provides the motive force to move the sea water through the double bottom spaces.
Once the tanks are flooded via either the bow access door or the ballast systems sea suction a double hulled tanker will, in most cases be at or near its “International Convention for the Prevention of Pollution from Ships” (MARPOL) required draft. The ship may either use the ballast pumps to temporarily fill the wing walls to increase the ships draft, propeller immersion or change the trim or for manoeuvring in a port. Then once at sea the bow access doors may be opened and the AUBALEX system used to start exchanging the ballast as the ship moves forward.
 Figure 2. shows the in tank view of how water is driven up into the wing walls as the ship moves forward.
AUBALEX PRINCIPALS OF OPERATION
AUBALEX allows sea water to flow through a ship as it moves through the water. The flow through the double bottom is driven by the pressure created as the ship moves through the water. Vela’s technology basically “ballasts” down a ship to the MARPOL required draft by losing buoyancy rather than adding water weight. This is achieved by opening up the bottom of the ship so that the ballast tanks are initially in “Free Communication” with the sea. Thus the water level in side the ballast tanks will rise up to a height equal to the ships draft, in other words, equal with the sea. Then as the ship starts to move forward the pressure created by its forward motion through the ocean drives a water column up into the wing walls of the ship’s double hull and then over board through sluice gates on deck or at the shear strake
At 14 kts there is enough pressure at the bow to raise a water column of over eight (8) feet (2.6 meters). If exit holes are placed in the double hull’s ballast tank’s outer shell at or near the ballast water line sufficient flow will be produced to ensure that the entire contents of the ship’s previously enclosed ballast spaces are changed three times in 36 hours – assuming a 14 kts speed, a CPS opening of 24 inches (600mm) or within any 500 mile area.
AUBALEX offers several advantages over treatment technologies. Treatment is the process where by ballast water is treated either by chemicals, with UV light or by heat. Two major problems with treatment technologies are not that they don’t work but rather that they are:
1) Very slow – the fastest one Vela can find requires chemical or heat treatment. This system offers quick discharge but at a very high price (see item #2 below). The UV treatments while also very expensive would increase a VLCC’s deballasting time from just 10-12 hours to about 7 days because the best claims to meet the standards of Regulation D-2.2 only operate at 500 tonnes/hour and these remain unproven claims! At the modest daily rate of $36,000 this would add $250,000 on to every voyage.
2) Very expensive to install and/or operate – Currently there is not a system offered for use on a VLCC. What is offered indicates that the expense of a heat treatment system capable of handling 600,000 bbls of water would take 200 tonnes of fuel and several days to accomplish.
This requires installation of heating coils and a steam system which alone will cost well over a million dollars per VLCC and would have a negative environmental impact adding greenhouse gases to the atmosphere---solving one environmental problem while adding to another. Likewise Chemical Treatment is an expensive system to install plus it consumes expensive chlorine---also adding this chemical to the seaway where ballast is discharged. Operating costs of the heat system will exceed $100,000 per voyage and chemical systems, already notorious for break downs, also require the handling of tons of chlorine or other chemicals to purify 600,000 bbls of ballast each voyage. Then there will be training and maintenance that cannot be estimated given that a viable system is not yet offered in the market.
AUBALEX is a much simpler system. The theory of its operation is easily understood, fits directly to the ship’s existing ballast system and best of all is automatic
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