Noduler i Bottenviken
Mangannodulerna (polymetalliska noduler) är runda stenlika konkretioner som bildats av
metalljoner i en process i gränsskiktet mellan bottensediment och havsvatten. Nodulerna
växer med cirka 0,2 millimeter per år. Det estimeras att Bottenviken totalt kan innehålla
cirka 20 miljoner ton mangannoduler.
Ur nodulerna kan det utvinnas:
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Mangan
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Järn
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Kisel
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Fosfor
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Andra ämnen som används för olika elektroniska och medicinska komponenter
1.
On the Bothnia Bay seafloor lies small potato-sized lumps – nodules – that contain minerals. In the Baltic Sea lies sediments.
2.
Via an air-lift technique, developed by Scandinavian Ocean Minerals, the seafloor is gently harvested for nodules or bottom sediment.
3.
On board the ship, nodules are filtered or, if sediment centrifuged
4.
Water and material that is not used is returned directly to the seafloor, which becomes oxygenated in the process.
5.
Nodules and sediment are transported to land where nodules are refined into, among other things, manganese, iron, silicon (used for batteries, solar cells and semiconductors) while sediment becomes biogas, hydrogen gas or green coal (used for fossil-free steel).