Feed Preparation

DOE-HDBK-3010-94

Appendix B; Plutonium Recovery Facility

- Weighing and Batching;

- Storage;

- Chainveyor.

There is a hood on the maintenance side of the glovebox that allows placement of material in

an airlock that can be opened from the operating side of the glovebox. The airlock is

designed with 12" by 12" replaceable inlet and outlet HEPA filters. Oxide is received

directly from the H-12 Plutonium Vault Facility. At the access hood, the oxide can is

removed from its outer containment vessel and swiped for contamination. It is then placed in

the airlock. Residue processed in H Plant consists largely of slag generated in the button

forming process, which is brought to the hood in a sealed red plastic pail. The pail is opened

in the hood, and the internal doubly bagged package is placed in the airlock.

The unpackaging station is simply an open area for removing the material from its primary

packaging and placing it in a critically safe metal can. An automatic can opener is provided

for opening sealed cans. Oxide cans and plastic bags are removed with glovebox waste

through either a bagport or a Central Research Canister.

Oxide that has no metal fines or other contaminants is moved down to the weighing station

where a dissolver batch is prepared and placed in a charge can. Incompletely oxidized

material must be burned to oxide before it is sent to the dissolving line. This is accomplished

in a small electric muffle furnace located in the glovebox, which can attain maximum

temperatures on the order of 1200 F. The unit is sized to oxidize an entire plutonium metal

button if necessary, and is insulated sufficiently to prevent exterior surface temperature from

rising above a maximum of 125 F. It draws combustion air from the process air system via

a small process air line with backflow preventers, and offgas from the furnace is routed to the

vessel vent system. The complete burning and cooldown cycle is controlled by an automatic

timer. The timer will not allow the furnace door to be opened before a preset minimum time

has passed. The door is also interlocked with a temperature signal to prevent opening the

door before the burn cycle is complete.

Cans of magnesium oxide are provided wherever oxide is handled in the glovebox. If metal

fines were to ignite while the material was unpackaged, heat transfer through the stainless

steel glovebox floor should put out the small fire. However, procedure calls for pouring the

sand over the material to ensure this is the case.

Slag residues normally require some size reduction prior to dissolution. This is conducted in

a small impactor installed in the glovebox. The device is mounted so as to prevent vibration

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