Molten salts insulated storage tank

A storage tank for molten salts, said storage tank comprising an annular metal wall defining a first inner surface and, adjacent to and substantially parallel to said first inner surface, a metal structure defining a second inner surface, with said second inner surface defining the tank's storage volume for molten salts;

• and
• wherein a compartmentalized insulation space comprising a plurality of separate void spaces is present between said first and second surfaces;
• wherein the second inner surface is provided with a plurality of openings configured to allow molten salts to flow from said storage volume into said plurality of void spaces in said insulation space;
• wherein the metal structure comprises a plurality of annular supports spaced apart over the length of the wall, said annular supports carrying elements providing the void spaces;
• and
• (a) wherein the elements are steel boxes, said steel boxes comprising at least one hole for the entry of molten salts;
• or
• (b) wherein the elements comprise an annular vertical wall positioned on the annular supports, with the vertical walls taken together forming the second inner surface, and the annular supports and vertical walls form a plurality of annular gutters, with the height of the verticals walls being smaller than the distance between two adjacent annular supports.