초록 ▼

Aquatic nuisance species (ANS) in ship's ballast water are killed by permeating to equilibrium a gaseous mixture consisting essentially of, preferably, ≧84% nitrogen, ≧11% carbon dioxide and ≦4% oxygen through ship's ballast water until the ballast water itself becomes (i) hyper

Aquatic nuisance species (ANS) in ship's ballast water are killed by permeating to equilibrium a gaseous mixture consisting essentially of, preferably, ≧84% nitrogen, ≧11% carbon dioxide and ≦4% oxygen through ship's ballast water until the ballast water itself becomes (i) hypercapnic to ≧20 ppm carbon dioxide, and, by association, (ii) acidic to pH≦7, while preferably further, and also, being rendered (iii) hypoxic to ≦1 ppm oxygen. The permeating is preferably realized by bubbling the gaseous mixture preferably obtained from an inert gas generator through the ballast water over the course of 2+ days while the ballast water is continually maintained a pressure less than atmosphere, preferably −2 p.s.i. or less. The (i) hypercapnic, (ii) acidic and (iii) hypoxic conditions—each of which can be independently realized—synergistically cooperate to kill a broad range of ANS in the ballast water without deleterious effect on the environment when, and if, the ballast water in which the balance of dissolved gases has been changed is discharged.

대표청구항 ▼

1. A method of killing aquatic nuisance species in ship's ballast water comprising:infusing carbon dioxide into the ship's ballast water at a level effective to kill aquatic nuisance species by hypercapnia. 2. The method according to claim 1 wherein the infusing is with a gaseous mixture of ≧

1. A method of killing aquatic nuisance species in ship's ballast water comprising:infusing carbon dioxide into the ship's ballast water at a level effective to kill aquatic nuisance species by hypercapnia. 2. The method according to claim 1 wherein the infusing is with a gaseous mixture of ≧11% carbon dioxide by molar volume. 3. The method according to claim 2 wherein the infusing with the gaseous mixture of ≧11% carbon dioxide transpires until the ballast water is hypercapnic to ≧20 ppm dissolved carbon dioxide. 4. The method according to claim 2 wherein the infusing transpires by bubbling the gaseous mixture through the ballast water. 5. The method according to claim 4 wherein the bubbling of the gaseous mixture is through the ballast water that is under less than atmospheric pressure. 6. The method according to claim 5 wherein the bubbling of the gaseous mixture through the ballast water less than atmospheric pressure is within ballast water tanks of the ship where ullage space gas pressure is −2 p.s.i. below atmospheric pressure or lower. 7. The method according to claim 1 that, concurrent with the infusing, further comprises:depleting oxygen in the ship's ballast water at a level effective to kill aquatic nuisance species by hypoxia. 8. The method according to claim 7 wherein the infusing is with a gaseous mixture of ≧11% carbon dioxide by molar volume. 9. The method according to claim 8 wherein the infusing with the gaseous mixture of ≧11% carbon dioxide transpires until the ballast water is hypercapnic to ≧20 ppm carbon dioxide. 10. The method according to claim 8 wherein the infusing transpires by bubbling the gaseous mixture through the ballast water. 11. The method according to claim 10 wherein the bubbling of the gaseous mixture is through the ballast water that is under less than atmospheric pressure. 12. The method according to claim 11 wherein the bubbling of the gaseous mixture through the ballast water less than atmospheric pressure transpires within ballast water tanks of the ship where tank ullage space gas pressure is −2 p.s.i. below atmospheric pressure, or lower. 13. The method according to claim 7 wherein the depleting transpires by act of substituting gases, including oxygen, that are initially dissolved in the ballast water by infusion of a gaseous mixture containing the carbon dioxide but also containing ≦4% oxygen. 14. The method according to claim 13 wherein the depleting with the gaseous mixture of ≦4% oxygen transpires until the ballast water is hypoxic to ≦1 ppm dissolved oxygen. 15. The method according to claim 13 wherein the depleting transpires by bubbling the gaseous mixture through the ballast water. 16. The method according to claim 15 wherein the bubbling of the gaseous mixture is through the ballast water that is under less than atmospheric pressure. 17. The method according to claim 16 wherein the bubbling of the gaseous mixture through the ballast water less than atmospheric pressure transpires within ballast water tanks of the ship where tank ullage space gas pressure is −2 p.s.i. below atmospheric pressure, or lower. 18. The method according to claim 7 that, concurrent with the infusing, further comprises:acidifying the ship's ballast water at a level effective to kill aquatic nuisance species. 19. The method according to claim 18 wherein the infusing is with a gaseous mixture of ≧11% carbon dioxide by molar volume;wherein the acidifying is concurrently realized by the chemical reaction 2 +H 2 O→H 2 CO 3 ⇄H + +HCO 3 − ,which chemical reaction is interpretable that carbon dioxide (CO 2 ) reacts with water (H 2 O) to form carbonic acid (H 2 CO 3 ), which carbonic acid then partially dissociates to form hydrogen (H + ) and bicarbonate ions (HCO 3 − ). 20. The method according to claim 19 wherein the infusing with the gaseous mixture of ≧11% carbo n dioxide transpires until both (1) the ballast water is hypercapnic to ≧20 ppm carbon dioxide, and (2) the same ballast water is acidic to pH≦7. 21. The method according to claim 19 wherein the infusing and, consequent to the infusing, the acidifying transpires by bubbling the gaseous mixture through the ballast water. 22. The method according to claim 21 wherein the bubbling of the gaseous mixture is through the ballast water that is under less than atmospheric pressure. 23. The method according to claim 22 wherein the bubbling of the gaseous mixture through the ballast water less than atmospheric pressure transpires within ballast water tanks of the ship where tank ullage space gas pressure is −2 p.s.i. below atmospheric pressure, or lower. 24. The method according to claim 18 wherein the depleting is transpires by act of substituting gases, including oxygen, that are initially dissolved in the ballast water by infusion of a gaseous mixture containing the carbon dioxide but also containing ≦4% oxygen. 25. The method according to claim 24 wherein the depleting with the gaseous mixture of ≦4% oxygen transpires until the ballast water is hypoxic to ≦1 ppm dissolved oxygen. 26. The method according to claim 24 wherein the depleting transpires by bubbling the gaseous mixture through the ballast water. 27. The method according to claim 26 wherein the bubbling of the gaseous mixture is through the ballast water that is under less than atmospheric pressure. 28. The method according to claim 27 wherein the bubbling of the gaseous mixture through the ballast water less than atmospheric pressure transpires within ballast water tanks of the ship where tank ullage space gas pressure is −2 p.s.i. below atmospheric pressure, or lower. 29. A method of reducing survival of aquatic nuisance species in ship's ballast water comprising:permeating to equilibrium a gaseous mixture consisting essentially of ≧84% nitrogen, ≧11% carbon dioxide and ≦4% oxygen through ship's ballast water until the ballast water ishypoxic to ≦1 ppm oxygen,hypercapnic to ≧20 ppm carbon dioxide, andacidic to pH≦7. 30. The method according to claim 29wherein the permeated gaseous mixture is the output of a marine inert gas generator. 31. The method according to claim 29wherein the permeated gaseous mixture that is output from a marine inert gas generator consists essentially ofnitrogen in the range from 87% to 84% mole percent,carbon dioxide in the range from 14% to 11% mole percent, andoxygen in the range from 2% to 4% mole percent. 32. The method according to claim 29 continued until the ship's ballast water until the ballast water ishypoxic to ≦1 ppm oxygen,hypercapnic to ≧20 ppm carbon dioxide, andacidic to pH≦7. 33. The method according to claim 29wherein the gaseous mixture is permeated to equilibrium within the ballast water by being bubbled through the ballast water. 34. The method according to claim 33wherein the gaseous mixture bubbled to equilibrium within the ballast water is so bubbled into ballast water under a pressure less than atmosphere. 35. The method according to claim 34wherein the gaseous mixture bubbled to equilibrium within the ballast water under a pressure less than atmosphere is into ballast water tanks of the ship where tank ullage space gas pressure is −2 p.s.i. below atmospheric pressure, or lower. 36. A system for reducing survival of aquatic nuisance species in ship's ballast water comprising:a gas generator producing a gaseous mixture enhanced in carbon dioxide relative to both (i) atmospheric proportion of carbon dioxide, and (ii) proportion of carbon dioxide that is dissolved in sea water;piping having and defining discharge orifices at the base of, and inside, the ship's ballast water tank; anda compressor pressuring the gaseous mixture received from the gas generator sufficiently so that, as delivered to the piping, i t will be forced out the discharge orifices and bubble upward through the ballast water;wherein gaseous interchange transpires between (i) the gaseous mixture, enhanced in carbon dioxide, that is within the bubbles and (ii) dissolved gases within the ballast water;wherein dissolved gases within the ballast water will become enhanced in carbon dioxide to a level inducing hypercapnia in aquatic nuisance species within the ballast water. 37. The system according to claim 36 wherein the gas generator is producing a gaseous mixture having ≧11% carbon dioxide by molar volume. 38. The system according to claim 36 wherein the gas generator producing the gaseous mixture enhanced in carbon dioxide comprises:an inert gas generator producing the gaseous mixture that is concurrently diminished in oxygen over both (i) atmospheric proportion of oxygen, and (ii) proportion of oxygen dissolved in sea water;wherein the gaseous interchange transpiring between (i) the gaseous mixture, diminished in oxygen, that is within the bubbles and (ii) the dissolved gases within the ballast water causes dissolved gases within the ballast water to become diminished in oxygen to a level inducing hypoxia in aquatic nuisance species within the ballast water. 39. The system according to claim 38 wherein the inert gas generator is producing a gaseous mixture having ≧11% carbon dioxide by molar volume. 40. The system according to claim 39 wherein the inert gas generator is producing a gaseous mixture having ≦4% oxygen by molar volume. 41. The system according to claim 36 further comprising:a blower evacuating gases from within the ullage space of the ship's tank so as to produce a pressure therein which is at least 2 p.s.i. less than prevailing atmospheric pressure outside the tank. 42. The system according to claim 36 wherein the piping comprises:a matrix of piping in a grid array at the base of, and inside, the ship's ballast water tank. 43. The system according to claim 42 wherein the discharge orifices of the piping are variously directed both upwards toward the top and the tank and downwards towards the base of the tank. 44. The system according to claim 36 wherein the compressor is producing a pressure more than 2 p.s.i. greater than a hydrostatic pressure then prevailing at the base of the ship's ullage tank. 45. The system according to claim 36 wherein the amount and constituents of gas produced by the inert gas generator, pressured by the compressor, and delivered to the piping to be bubbled upwards through the ballast water, is sufficient to render the ballast water hypoxic to ≦1 ppm oxygen, hypercapnic to ≧20 ppm carbon dioxide, and acidic to pH≦7. 46. The system according to claim 45 wherein the amount and constituents of gas produced by the inert gas generator, pressured by the compressor, and delivered to the piping to be bubbled upwards through the ballast water, is sufficient to so render the ballast water hypoxic to ≦1 ppm oxygen, hypercapnic to ≧20 ppm carbon dioxide, and acidic to pH≦7 at a rate sufficient to establish equilibrium in the ballast water within a period less than (1) one-half the normal voyage duration of the ship minus (2) the required time for aquatic nuisance species to die to the 90% level.