Pump system, method and uses for transporting injection water to an underwater injection well

A method for transporting injection water (10) to an underwater injection well (12), where the method uses a pump system (2) comprising a pressure-tight enclosure (14), which includes:

• a pump arrangement (18) for pumping the injection water (10);
• a drive arrangement (20) connected to the pump arrangement (18) for operation of the latter;
• a cooling arrangement (46) for removing heat from the interior of the enclosure (14);
• and
• at least one control unit (48) for operating control of at least said drive arrangement (20);
• wherein the enclosure (14) also comprises:
• an inlet (24), which is flow-connected to an upstream side of the pump arrangement (18);
• and
• an outlet (28), which is flow-connected to a downstream side of the pump arrangement (18);
• wherein the method comprises the following steps:
• (A) lowering the pressure-tight enclosure (14) down into the water and locating the enclosure (14) underwater,
• characterized in that the method also comprises the following steps:
• (B) flow-connecting the inlet (24) of enclosure (14) to a body of water (4) in which the enclosure (14) is located, water from this body of water (4) being used as injection water (10) to said underwater injection well (12);
• (C) flow-connecting the outlet (28) of the enclosure (14) to the injection well (12);
• and
• (D) starting said drive arrangement (20) and thereby the pump arrangement (18) in order thus to pump the injection water (10) onwards to the injection well (12).