| 摘要 |
Canisters 400 are stored above ground in separate chambers of a concrete vault. The vault is constructed from pre-cast concrete sections 120, 140, 150. Each chamber has a stainless steel liner 450, defining inner and outer annular spaces 510, 520 between the hot canister wall 402 and the concrete wall 465. Cooling air flows through both spaces 510,520 by natural convection. Cold air flows in through base level vents 170. Hot air from the outer annular spaces discharges through upper vents 172 formed in the concrete and that from the inner space discharges through a gap 436 between a metal lid 430 and flanges 432, 434. Slots 532 are formed between inner and outer annular spaces to allow discharge of all hot air even if one vent is to become blocked. The concrete walls are cooled by further ducts formed as an integral part of the pre-cast structures. |
