OREANDA-NEWS. Toshiba Corporation today unveiled a remotely operated Fuel Removal System (FRS) for removing debris and fuel from the spent fuel pool (SFP) of Fukushima Daiichi Nuclear Power Station Unit 3. The FRS will be installed at the Fukushima site from now, and is expected to start operation in fiscal 2017.

In Unit 3, debris from the explosion of hydrogen that destroyed the upper part of the reactor building now litters the operation floor* and the SFP. In order to return Unit 3 to a stable condition, it is necessary to first remove the debris and then all of the fuel. The FRS developed by Toshiba is designed to do this, and to place fuels in a Transfer Vessel (TV) that can be securely sealed. Once that is done, the FRS will lift the TV to an above-ground floor of the reactor building, for transportation to a temporary storage site.

The FRS consists of a Fuel Handling Machine (FHM) for removing the debris and fuel, and cranes for bringing in TVs, closing their lids and hoisting them up to ground-level floor. The FHM is equipped with two manipulators capable of cutting and grabbing debris and a mast and fuel grapple tool for taking out fuel. The manipulator tips, Auxiliary Hoists and Fuel Grapple tool attached to mast can be replaced with an appropriate cutting or gripping jig via remote control, depending to the state of the debris in the pool. The crane section consists of the Main Hoist with the TV Lifting Rig, which transfers fuel to the TVs, and an Auxiliary Hoist for removing and securing the TV primary lid. Testing and training had been performed up to last December, and the removal of debris and fuel is scheduled to begin in fiscal 2017.

Toshiba will continue to develop technologies that will contribute to the decommissioning of Fukushima Daiichi Nuclear Power Station.
 

Note:
*
Operation floor: The top floor of the reactor building, where fuel exchange work is performed during periodic inspection.

Overview of the Fuel Removal System

Weight

FHM: Approx. 74 tons

Crane: Approx. 90 tons

External dimensions

FHM: Approx. 15 m (L) * 6m (W) * 8 m (H)

Crane: Approx. 15m (L) * 7m (W) * 10m (H)

Specifications

FHM: Two manipulators, one mast with Fuel Grapple tool, two Aux. Hoists

Crane: One Main Hoist, one Aux. Hoist, one TV Lifting Rig, one TV Lid Bolting Tool
Fuel Removal System  
Fuel Removal System