A method for forming an integrated passive cooling containment structure, the method comprising:
- forming a steel annulus structure, the steel annulus structure including a concentric arrangement of an inner steel cylindrical shell and an outer steel cylindrical shell, an inner surface of the inner steel cylindrical shell defining a lateral boundary of a containment environment that is configured to accommodate a nuclear reactor, an outer surface of the inner steel cylindrical shell and an inner surface of the outer steel cylindrical shell defining inner and outer diameters, respectively, of an annular gap space between the inner steel cylindrical shell and the outer steel cylindrical shell;
- forming a concrete donut structure at a bottom of the annular gap space, such that the concrete donut structure fills a lower region of the annular gap space;
- forming a plurality of concrete columns spaced apart azimuthally around a circumference of the annular gap space and extending in parallel to a top of the annular gap space, such that the outer steel cylindrical shell, the inner steel cylindrical shell, the plurality of concrete columns, and the concrete donut structure at least partially define one or more coolant channels in the annular gap space, the one or more coolant channels extending from a top surface of the concrete donut structure to the top of the annular gap space, such that
- two or more concrete columns, of the plurality of concrete columns, each have a radial diameter, in a radial direction of the annular gap space, that equals a radial distance of the annular gap space between an inner diameter and an outer diameter of the annular gap space over at least a portion of a vertical height of each of the two or more concrete columns, such that the two or more concrete columns azimuthally partition at least a portion of the annular gap space into two or more isolated coolant channels that extend vertically through at least the portion of the annular gap space, and
- the outer steel cylindrical shell includes two or more coolant supply ports that are each configured to direct coolant fluid into a separate coolant channel of the two or more isolated coolant channels;
- and
- installing one or more coolant supply ports at a bottom of the one or more coolant channels, the one or more coolant supply ports configured to couple with a coolant source via one or more coolant fluid supply conduits, such that the one or more coolant supply ports are configured to direct a coolant fluid into a bottom region of the one or more coolant channels such that the coolant fluid rises through the one or more coolant channels towards a top of the one or more coolant channels, according to a change in coolant fluid buoyancy based on the coolant fluid absorbing heat rejected from the containment environment via the inner steel cylindrical shell.