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Tripartite 2008. Ballast Water Developments . International Chamber of Shipping. Ballast Water Regulations - IMO. Ballast Water Management Convention, 2004. Progress toward Entry into Force Criteria: 30 States representing 35% world ’ s GT Currently: 16 States representing 14.24%
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Tripartite 2008 Ballast Water Developments International Chamber of Shipping
Ballast Water Management Convention, 2004 Progress toward Entry into Force • Criteria: 30 States representing 35% world’s GT • Currently: 16 States representing 14.24% • Barbados, Egypt, France, Kenya, Kiribati, Liberia, Norway, Maldives, Mexico, Nigeria, Norway, Saint Kitts and Nevis, South Africa, Spain, Syrian Arab Republic and Tuvalu
Status of BW Convention Guidelines • 15 Guidelines completed • Port State Control Guidelines under development • No further impediment to ratification?
Practical Considerations • ~50,000 existing vessels require BW Treatment Systems over 7 years • New building rate ~1400/year • Manufacturing capacity?
25th IMO Assembly (Nov 07) • Assembly Resolution A.1005(25) • A ship constructed in 2009 will not be required to comply with regulation D-2 until its second annual survey, but no later than 31 Dec 2011.
MEPC 58 (October 08) Too early to make a judgment …. ……reconsider at MEPC 59 (July 2009)
Treatment Options • Filtration – Sediment and particles removed by disc or screen filters – Self-cleaning procedures – waste stream directly discharged overboard – filtration grades down to 100/50/20 microns. Filters create back pressure (rapidly increasing for small filtration grades)– self-cleaning procedures reduce flow rates (high sediment loads) • Cyclonic Separation (Hydro Cyclone) – Acceleration of the water by rotational flow inside the cyclone – Separation of solids due to centrifugal forces – only particles with a specific gravity less than water can be separated.
Treatment Options • Cavitation/Ultrasound– Venturi pipes generate cavitation bubbles that implode and disrupt the cell walls of organisms/ External creation of ultra-sound applied to BW – Cavitation units create back pressure – additional high frequency noise – difficult to develop control instruments. • Coagulation, Flocculation – Addition of coagulants to ballast water that facilitate creation of flocs to remove by filtration or magnetic separation – storage tank for additives needed - sludge tank for separated flocs required – time consuming process • De-oxygenation/Gas super-saturation – removal of disolved oxygen in BW and replacement by inactive gases (e.g. N, CO2) – time consuming process – controlled atmosphere in tanks needed to avoid re-oxygenation (P/V valves required)
Treatment Options • Electrolysis/Electro-chlorination – Electric current applied to BW within an electrolytic chamber – sodium chloride is split into active Chlorine which disinfects the water – only applicable in water with salt content– creation of unwanted by-products dependant upon applied current and electrodes used– Neutralization component required which may require carriage of chemicals. • Ozone – Ozone is produced on board and injected into the BW as a disinfectant – Unwanted by-products may be produced. • Chemical additives – Direct addition of a chemical that has disinfectant properties to the BW – Hydrogen peroxide (H2O2), Peracetic acid (Peraclean), Chlorine, Chlorine Dioxide, Vitamin K (SeaKleen) – Dosing requires careful adjustment, storage required, holding time in tank may be required.
Treatment Options • UV radiation – Amalgam lamps surrounded by quartz sleeves produce UV radiation – UV light attacks/breaks cell membrane of organisms and pathogens – efficacy dependant upon turbidity (sediments) – UV lamps need to be maintained. • UV radiation with catalyst TiO2– UV light acting with the catalyst Titanium Dioxide create free hydroxyl radicals (OH(-)ions) that disrupt the cell membrane – Efficacy dependant upon turbidity of BW – UV lights need to be maintained