NUCLEAR REACTOR PRESSURE VESSEL, MODIFYING METHOD OF SURFACE OF NUCLEAR REACTOR PRESSURE VESSEL AND MOVABLE TYPE APPARATUS FOR MODIFING SURFACE OF THE SAME

摘要

The present invention provides a nuclear reactor pressure vessel having a lower header, an outer wall of which is modified with an oxide film having a fine uneven structure, wherein a corium is disposed on the lower header when a core is melted in the event of a critical atomic accident. In addition, the present invention provides a corium cooling system. The corium cooling system comprises: the nuclear reactor pressure vessel; a shield vessel which forms a nuclear reactor cavity by accommodating the nuclear reactor pressure vessel so as to be spaced apart from the nuclear reactor pressure vessel and has a shield wall for blocking heat and radioactivity; and a containment vessel which accommodates the nuclear reactor pressure vessel and the shield vessel, wherein a coolant is disposed between the nuclear reactor cavity, the containment vessel and the nuclear reactor pressure vessel. Furthermore, the present invention provides a modification method for an oxide film and a movable type surface modification apparatus for realizing the modification method.