A device for separating a shielding slab for a heavy water reactor according to an embodiment includes: a body; a circular rail installed on at least one side of the body; and a decommissioner for decommissioning a shielding slab installed on the circular rail and installed on an inner wall of a heavy water reactor, wherein the decommissioner includes a decommission head moving on the circular rail, a separator installed in the decommission head and separating and desalinizing the shielding slab, and a gripper installed in the decommission head and gripping the separated shielding slab.

Provided is a remotely operated manipulator which can be applied to a space which is wider on a back side than at an opening part, which has a simple structure, high stiffness, and high reliability. The remotely operated manipulator of the present invention includes: a circular base fixed to a wall surface; a beam which rotates on the circular base; a trolley which moves on the beam; and a mast which is raised and lowered with respect to the trolley and is mounted with a tool unit at a tip. Stiffness is improved by directly fixing the beam to the wall surface by a beam fixing device. Further, a work region is expanded by mounting a bending mast on the tip of the mast.

A device for removing shielding balls from calandria of a heavy water reactor is provided. The device includes a head for moving the shielding balls positioned inside of an end shield of the calandria to an outside of the end shield; and a mover for moving the head to the end shield of the calandria. The head includes a head body, an opening former installed on the head body and configured to form an opening in the end shield, and a gate installed on the head body and configured to control an amount of the shielding balls discharged to the outside through the opening.

A mobile melting device for consolidating contaminated scrap and to a corresponding method. The melting device has a crucible chamber and a crucible base. The crucible is arranged on the crucible base during operation, and the crucible base and the crucible chamber together form a gas-tight furnace housing. It is thus possible to carry out the method in a vacuum or under protective gas such that even a reactive material can be consolidated. The melting device can be assembled and disassembled with little effort.

A method for decommissioning a nuclear facility includes: floating a nuclear reactor pressure vessel above a cavity; positioning a mounting device on bio-protective concrete to cover the cavity with the mounting device; mounting a lower portion of the nuclear reactor pressure vessel on the mounting device; and cutting and decommissioning the nuclear reactor pressure vessel mounted on the mounting device.

An apparatus for analyzing nuclides and the concentration thereof in waste contained in a radioactive waste packaging container according to the present disclosure relates to an apparatus that has detector devices located above/under the waste packaging container and performs nuclide and concentration analysis on the waste in the packaging container by scanning the packaging container in the longitudinal direction thereof using a forward/backward driving device. In particular, upper/lower detector modules are equipped with multiple high-resolution gamma ray detectors to increase inspection efficiency, each module is designed to be driven up/down, and each detector in the module is designed to be driven left/right, thereby performing nuclide and concentration analysis on various types of packaging containers regardless of the size thereof.

A method for decommissioning a nuclear facility includes: floating the nuclear reactor pressure vessel above the cavity; rotating the reactor pressure vessel so that the upper portion of the nuclear reactor pressure vessel is closer to the bio-protective concrete than the lower portion; mounting the upper portion of the nuclear reactor pressure vessel on the neighboring upper surface of the bio-protective concrete; and cutting and decommissioning the nuclear reactor pressure vessel mounted on the neighboring upper surface.

A nuclear reactor decommissioning system according to an embodiment includes a cutting device to cut a reactor, a lifting device inserted inside the reactor to lift the reactor, and a shielding device that is positioned between the reactor and the lifting device and blocks radioactive dust generated by the cutting device from spreading.

A method for decommissioning a heavy water reactor facility includes: opening an upper part of the calandria vault; inserting a support device into an inner part of the calandria vault through the upper part of the calandria vault to support the main shell of the calandria; cutting between the main shell and the sub-shell of the calandria by inserting a cutting device into the inner part of the calandria vault through the upper part of the calandria vault; and drawing out the main shell of the calandria to the outside of the calandria vault by moving the support device from the inner part of the calandria vault to the outside through the upper part.

A safety cover structure of a nuclear facility is disclosed. The safety cover structure of a nuclear facility includes: a cover portion rotatably provided over body protection concrete so as to cover a cavity in which a reactor pressure container is positioned; a driving part for providing rotational driving power to the cover part; an opening and closing portion provided at the cover portion and thus products from the cutting and dismantling of the reactor pressure contain move therethrough; a fire extinguishing portion for extinguishing a fire occurring inside the cover portion; a radiation sensor which is provided on the cover portion and which measures radiation dose; and an alarming portion, which receives a sensing signal of the radiation sensor so as to issue an alert when radiation greater than or equal to a predetermined value is discharged from the reactor pressure container.