Fluid flow converter

An apparatus for converting rotation to fluid flow, comprising:

• a fluid conduit coiled around a rotational axis, said fluid conduit having a first inlet for receiving a first fluid having a first density and a second inlet for receiving a second fluid having a second density, different from said first density, and a first outlet for output of said first fluid and a second outlet for output of said second fluid;
• said fluid conduit being rotatable around said rotational axis in a first angular direction such that first fluid portions of said first fluid and second fluid portions of said second fluid are transported along said fluid conduit towards said first outlet, while being pressurized;
• and
• a motor coupled to said fluid conduit to rotate said fluid conduit around said rotational axis in a first angular direction such that first fluid portions of said first fluid and said second fluid portions of second fluid are transported along said fluid conduit towards said first outlet, while being pressurized;
• and
• a fluid returning arrangement, fluid flow connecting said second outlet and said second inlet for selectively allowing pressurized second fluid to return from said second outlet to said second inlet, while depressurizing said pressurized second fluid.