Method and apparatus for killing microorganisms in ship ballast water
AssigneeBrowning Transport Management, Inc.
InventorWilson J. Browning, Jr.
Life of this patent
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Abstract
A method and apparatus for treating ship ballast water before it is discharged into coastal waters. The ballast water may contain harmful non-indigenous microorganisms. Before discharge, the ballast water is oxygenated and deoxygenated to reduce the populations of anaerobic and aerobic microorganisms, respectively. If anaerobic microorganisms are of no concern, the oxygenation step can be eliminated.
Claims28
A process for treating ballast water, in a space defining a hold or ballast tank of a ship, to reduce an initial population of microorganisms in the ballast water, said microorganisms comprising aerobic microorganisms, said process comprising the steps of:
- deoxygenating the ballast water containing the aerobic microorganisms by agitating the ballast water under a vacuum for a first period of time, wherein said deoxygenating step removes dissolved oxygen from the ballast water;
- and
- after said deoxygenating step, sealing the space containing the treated ballast water for a second period of time until the initial population has been reduced.
A process for treating ballast water, as it is being pumped from ambient water alongside a ship into a space defining a hold or ballast tank of a ship, to reduce an initial population of microorganisms in the ballast water, said microorganisms comprising aerobic microorganisms, said process comprising the steps of:
- pumping the water to create turbulence therein which produces agitation of the water;
- and
- deoxygenating the pumped ballast water containing the aerobic microorganisms by subjecting the agitated ballast water to a vacuum for a first period of time, wherein said deoxygenating step removes dissolved oxygen from the ballast water;
- and
- after said deoxygenating step, sealing the space containing the treated ballast water for a second period of time until a percentage of the population that has been killed is at least 50%.
An apparatus for treating ballast water, in a space defining a hold or a ballast tank of a ship, to reduce an initial population of microorganisms in the ballast water, said microorganisms comprising aerobic microorganisms, said apparatus comprising:
- means for deoxygenating the ballast water containing the aerobic microorganisms by agitating the ballast water under a vacuum for a first period of time, thereby to remove dissolved oxygen from the ballast water;
- and
- means for sealing the space containing the treated ballast water for a second period of time until the initial population has been reduced,
- wherein said sealing means seals the space until a percentage of the initial population that has been killed is at least 90%,
- wherein the ballast water also contains anaerobic microorganisms, wherein the ballast water flows in a direction from said deoxygenating means toward said space;
- and
- further comprising means, positioned upstream from said deoxygenating means, for oxygenating the ballast water to kill the anaerobic microorganisms or to debilitate them to a point where their reproduction rate is substantially reduced even during said second period when the habitat of said anaerobic microorganisms is anaerobic.
Dependencies are inferred from the claim text.