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Submarine - Wikipedia, the free encyclopedia To control their weight, submarines are equipped with ballast tanks, which can be filled with either outside water or pressurized air. For general submersion or surfacing, submarines use the forward and aft tanks, called Main Ballast Tanks or MBTs, which are opened and completely filled with water to submerge, or filled by pressurized air to surface. Depth control tanks can be located either near the submarine's centre of gravity, or separated along the submarine body to prevent affecting trim. en.wikipedia.org /wiki/Submarine   (8866 words)

PWSRCAC--Ballast Water Treatment Facility Ballast water that is not contaminated with oil remnants can be discharged into the sea without any processing; however, such discharge may introduce non-indigenous or nuisance species at the location of discharge. Future ballast water treatment volumes are expected to decrease with the increased use of double-hulled tankers, which can segregate ballast water in the space between the cargo tanks and the outer hull. Ballast water is pumped from the tankers to the large process tanks #92, #93, and #94; these tanks are commonly referred to as the 90s tanks, or gravity separation tanks. www.pwsrcac.org /projects/TermOps/bwtf.html   (1012 words)

NOAA GLERL Computational Modeling of Ballast Tanks to Improve Understanding and Maximize Effectiveness of ... Ballast water discharge is considered to be the primary mechanism responsible for the introduction of nonindigenous aquatic species into coastal ecosystems. The former requires that ballast tanks be emptied completely and then refilled at sea, while the latter requires pumping of mid-ocean water, usually entering at the tank bottom, into a full or partially full ballast tank and allowing the water to overflow the tank for a given tank volume multiple. In order to investigate the influence of the tank structures, two separate grids were developed for the full-scale tank, one with all of the tank structure as shown in Figure 5 and one that neglects the reinforcing stringers. www.glerl.noaa.gov /res/Task_rpts/2003/nsreid10-2.html   (2333 words)

MITSG-CCR: Marine Bioinvasions: Fact Sheet on Ballast Water Ballast water is fresh or saltwater held in the ballast tanks and cargo holds of ships. Ballast water may also be used to add weight so that a ship sinks low enough in the water to pass under bridges and other structures. Usually ballast water is pumped into ballast tanks when a ship has delivered cargo to a port and is departing with less cargo or no cargo. massbay.mit.edu /exoticspecies/ballast/fact.html   (1269 words)

Self Adjusting Soft Ballast Tanks Ballast tanks are simply containers that can store air or water in order to increase or decrease lift. The level of the air in each ballast tank is maintained by the air flowing into the tank as well as the level at which the air is being release from the tank. When the pipe is rotated down, then the air bubbling up into the ballast will slowly displace the water in the tank until the water level in the tank descends enough to allow the air to again flow out of the vent pipe. www.submarineboat.com /sub/ballast_tanks.html   (1145 words)

Report on Ballast Water and Hull Fouling in Victoria   (Site not responding. Last check: 2007-10-30) Ballast tanks are dosed with a concentration of peroxide sufficient to destroy cell integrity by attacking fatty acids within the membrane causing tissue damage Ballast exchange is the method currently recommended for use by industry to minimise the risk of organism translocation. In addition, the discharge of ballast water from ships' ballast tanks to a sewage treatment facility would require that either the sewage plant be located within the port precinct, or that many kilometres of pipeline be installed to allow delivery of the ballast water. www.parliament.vic.gov.au /enrc_old/ballast/Ballast-39.htm   (4405 words)

Corrosion Protection Systems for Ballast Tanks and Void Spaces   (Site not responding. Last check: 2007-10-30) This area of the ballast tanks tend to be more anodic than the rest of the tank and this situation is made worse be the complex structure. In the mid-section of the ballast tank, in the area of the boottop, rust scales can be relatively self-healing during the early service life of the coating. Ballast tanks on those vessels using inert gas have to be very carefully ventilated, particularly in double bottom tanks, before inspections can take place. website.lineone.net /~amteccorrosion/cpsforbtanks.html   (2323 words)

Ballast - Wikipedia, the free encyclopedia Track ballast, railway track-bed, on which sleepers and track is laid Ballast tanks, a device used on submarines and other submersibles to control buoyancy Ballast (electrical), used to stabilize the current flow in lamps en.wikipedia.org /wiki/Ballast   (113 words)

PWSRCAC--NIS & Ballast Water When an empty crude oil tank is filled with ballast water, that water is typically referred to as "unsegregated" or "dirty" ballast because the ballast uses the same tanks as the crude oil rather than a separate tank. Studies completed on unsegregated oily ballast water at the VMT have shown that the amounts of hydrocarbons in the oily ballast water are lethal to aquatic or benthic species in the ballast tanks. Ballast water is pumped out of the segregated ballast water tanks and discharged directly into Prince William Sound and Port Valdez with no treatment. www.pwsrcac.org /projects/NIS/bw.html   (971 words)

Fish and Wildlife Research Institute The ballast tanks contain seawater, or ballast water, which is pumped into or discharged from the ship during cargo transfer, usually in harbors and nearshore waters. If the organisms within a ship’s ballast tanks survive the trip to the next destination, they may be released with the ballast water into waters in which they do not naturally occur. Ballast tanks typically have an open pipe—called a sounding pipe—that is used to measure, or sound, the amount of water inside a ship’s ballast tank. www.floridamarine.org /features/view_article.asp?id=23967   (1118 words)

Yacht Design - Water Ballast in Racing Sailboats If the water ballast tanks are divided into multiple compartments fore and aft, certain sections may be filled to correct for trim. The only design restrictions other than maximum capacity are that the tanks must be located aft of the chainplates, be integral or permanently secured to the hull, and be symmetrically arranged about the boats center line. With such well-defined dimensions, weight and stability, the 600 liter capacity of the water ballast tanks was determined as a safe and prudent amount. www.vgyd.com /article_5_ballast.html   (907 words)

NBIC: Ballast Water Management Strategies This process reduces the density of coastal organisms in ballast tanks that may be able to invade a recipient port, replacing them with oceanic organisms with a lower probability of survival in nearshore waters. Ballast water exchange is recommended as a voluntary measure by the International Maritime Organization (IMO). NISA issued mandatory ballast management reporting and voluntary ballast exchange guidelines to all vessels that enter U.S. waters from outside the EEZ, with the exception of military vessels, crude oil tankers that carry out coastwise trade, and some passenger ships that are equipped with ballast treatment systems. invasions.si.edu /nbic/managementpract.html   (283 words)

Mission2005: The Atlantis Projects When the ballast tanks take in water, the seawater they contain is of the same density as the surrounding water, so they can be treated as part of the sea water. Thus the ballast tanks should be placed below the center of buoyancy of the vessel when the ballast tanks are empty (initial center of buoyancy). This is like a small ballast tank with a different posiiton than the main tanks so as to change the location of the vessel's center of buoyancy. web.mit.edu /12.000/www/m2005/a1/Robotics/ballast.htm   (926 words)

Ballast Water Management: New International Standards and National Invasive Species Act Reauthorization   (Site not responding. Last check: 2007-10-30) The ballast water performance standards require that vessels subject to the performance standards reduce the concentration of viable organisms (expressed in terms of the number of organisms per unit volume of discharged ballast water) discharged from their ballast tanks to the levels specified in the Convention’s regulations. In cases where a vessel is unable to conduct ballast water exchange as above, it must perform the exchange as far from the nearest land as possible, and in all cases at least 50 nautical miles from the nearest land and in water at least 200 meters in depth. An existing vessel with a ballast water capacity of 1,500 - 5,000 cubic meters (m3) is to conduct ballast water management that meets either the ballast water exchange standard or the ballast water performance standard until 2014, after which time the vessel is to meet the ballast water performance standard. www.house.gov /transportation/cgmt/03-25-04/03-25-04memo.html   (3521 words)

Banks Power — Project Sidewinder gets balance from ballast tanks for traction and cooling in the Bonneville race ...   (Site not responding. Last check: 2007-10-30) Twin batteries, a 40-gallon intercooling ice water reservoir and the 22-gallon fuel cell all contribute ballast to the rear of the vehicle for traction at Bonneville. Ballast over the drive wheels is the best way to improve traction while simultaneously offsetting any aerodynamic lift at high speed. Because ice water is used for the air-to-water intercooling of the turbocharged intake air, the ideal place for the 40-gallon water reservoir is at the rear of the truck to also serve as ballast. www.bankspower.com /bighoss/sidewinder-ballast_tank.cfm   (216 words)

v7ndotcom elursrebmem v7ndotcoms elursrebmems Ballast tanks were used to submerge the HUNLEY, and the water was pumped out to return to the surface. The prototype torpedo was powered by a reciprocating motor driven by a tank of compressed air at a pressure of 48 bars (700 PSI), and had a range of 180 meters at 11 KPH (200 yards at six knots). A smaller auxiliary ballast tank was filled to the level needed to acquire a slight positive buoyancy given the number of crew, which ranged from seven to nine men, and amount of stores carried by the HOLLAND during a sortie. www.toprankingcompany.com /invention-of-submarine.htm   (7741 words)

Discussion Forum: Ballast Tank Reclassification In the case that no ballast is to be discharged in a cargo operation, this arrangement can apply in consultation with the authorities, and ordinary ballast may be regarded as temporarily permanent. I would suggest that if the tanks were isolated from the ballast system and the sea, they would actually have the status of cargo tanks, and their contents would be regarded effectively as 'cargo'... Naval ballasting of fighting ships (as against supplyships) is done to maintain correct trim in ships that are generally of very fine lines and very sensitive to the state of the magazines and fuel tanks in particular. globallast.imo.org /forum/display_topic_threads.asp?ForumID=4&TopicID=90&get=last   (1296 words)

Global Marine Oil Pollution Information Gateway • Facts • Operational discharges of oil Also, oil cargo or fuel tanks were used for ballast water and, consequently, oil was discharged into the sea when tankers flushed out the oil-contaminated ballast water to replace it with new oil. Ballast water is taken on board to maintain stability, such as when a vessel is sailing empty to pick up cargo or after having unloaded cargo. Ballast water contained in segregated ballast tanks never come into contact with either cargo oil or fuel oil. oils.gpa.unep.org /facts/operational.htm   (1591 words)

MBNMS: Ballast Water Deoxygenation Can Prevent Species Introductions While Reducing Ship Corrosion Although several ballast tank treatments to prevent transport of aquatic organisms appear promising, all existing approaches will result in significant costs to the shipping industry. Purging of oxygen from ballast tanks with nitrogen was recently found to be a cost-effective technique for reducing corrosion. Ballast water deoxygenation certainly deserves further exploration as a potential high priority treatment option, at least until international legislation mandates total mortality of ballast water organisms. bonita.mbnms.nos.noaa.gov /research/techreports/trtamburri_1.html   (745 words)

Submarines: How They Work - Archimedes' Principle Buoyancy is controlled by the ballast tanks, which are found between the submarine's inner and outer hulls. At this time, the ballast tanks are mainly full of air. The submarine ballast tanks now filled with seawater is denser than the surrounding water. www.onr.navy.mil /focus/blowballast/sub/work3.htm   (184 words)

FR Doc 04-17096 The tank (or pair of tanks) is pumped down to the point where the pumps lose suction, and then the tank is pumped back up to the original level. A ``full exchange'' using the ``empty/refill'' method means that the ballast tanks are pumped down to the point where the pumps lose suction, and the tank is then refilled to the original level. To change the submission requirements of ballast water reports for tugs and barges from 24 hours to 30 days would delay the accounting of BWM practices, thus denying the Coast Guard the means of enforcing compliance with mandatory ballast water reporting requirements. a257.g.akamaitech.net /7/257/2422/06jun20041800/edocket.access.gpo.gov/2004/04-17096.htm   (9653 words)

Flushing of ballast tanks — Belgian Biodiversity Platform   (Site not responding. Last check: 2007-10-30) Flushing of ballast tanks with seawater has been proposed to reduce the risk of invasion associated with residual ballast in 'no ballast on board' ships. Using diapausing eggs isolated from ballast sediments - as well as from Lake Erie sediment - this study investigated the impact of salinity (0, 8 and 35‰) and temperature (10, 20 and 30 °C) on the cumulative abundance and species richness of hatched zooplankton taxa. The efficacy of salinity as a ballast treatment method was temperature dependent, although the direction of the effect was case-specific. www.biodiversity.be /News/flushing-of-ballast-tanks   (259 words)

Sea Grant of NC ~ Magazines Within the Caspian Prince’s hold and ballast tanks are millions of gallons of seawater, drawn from the northern European harbor to lend stability and trim to the vessel during its two-week ocean crossing. Ballast water exchange on the high seas greatly reduces the chances of ships ferrying planktonic aquatic organisms from one nearshore area to another. Along with mid-ocean ballast water exchange and reporting, the rules would approve alternative “environmentally sound” methods of ballast water management as they are developed and tested for effectiveness. www.ncseagrant.com /index.cfm?fuseaction=story&pubid=126&storyid=156   (2445 words)

New method for controlling invasive species in ballast water A new method to reduce rust and corrosion in the ballast tanks of ocean vessels may also be key to preventing the spread of foreign aquatic species that stow away in ballast water. Reducing oxygen in ballast water to a low level can kill as much as 80 percent of the organisms in the water, according to the researchers. Rusting of ballast tanks as a result of exposure to seawater is a big problem for the shipping industry. www.greatlakesdirectory.org /zarticles/19ballast.htm   (748 words)

Ballast Water Research: Tests Continue on Glutaraldehyde   (Site not responding. Last check: 2007-10-30) The concern is with residual ballast (usually a few hundred metric tons) that cannot be pumped out of ballast tanks. Glutaraldehyde may be an option for killing ballast water organisms, some scientists believe, because studies have shown that the compound kills small life forms yet it won't bioaccumulate, or persist in the environment. If the data look promising (that is, if ballast tanks can be treated with concentrations that will eliminate a substantial number of organisms with low environmental risk), the researchers will conduct an actual shipboard application and track the concentrations as the ship travels across the Atlantic. www.miseagrant.umich.edu /pubs/up/fall00/ballast.html   (738 words)

Self Adjusting Soft Ballast Tanks The ballast sled is now in it full forward position and I put on a dive mask and drop through the open hatch just long enough to retrieve two air lines stored on the front deck. As the hull empties the ballast sled lead screw is moving the sled further aft causing the bow to rise slightly. The variable tanks adjust your buoyancy depending on passenger load, equipment load, water salinity, etc., and the main tank makes sure your top hatch sticks up far enough out of the water so that you do not flood when it is opened. www.submarineboat.com /sub/submarine_101.html   (4512 words)

Matter and Atoms   (Site not responding. Last check: 2007-10-30) There is a trim tank in the forward section of the submarine, a trim tank in the rear section of the submarine, and trim is maintained by adjusting the relative amounts of water in these tanks. Then, ignoring the increment of pressure added by the water in the tank as it gets deeper, the pressure of the water against the sides and bottom of the tank is exactly the same as the pressure on the water on top of the tank. the surface of the tank was under heavy pressure and the tank was not very deep, meaning the pressure was the almost the same at the top and bottom of the tank and the difference could be ignored. www.kosmoi.com /Technology/Engineering/Materials   (6118 words)

Discussion Forum: On shore ballast tanks in tanker loading The ballast water from the tank will be discharged and treated over a periode of 6 days, 24 hours a day. As discussed on the phone the ballast water will be treated on a by-pass discharge line where the treatment plant will be installed. The sand will normally settle on the ballast tank bottom while the fine particles of silt will be disperged in the water and follow the flow into the collection tank. globallast.imo.org /forum/display_topic_threads.asp?ForumID=1&TopicID=94&get=last   (459 words)

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