Long-term passive CANDU containment response after a design-basis accident
- Atomic Energy of Canada Ltd., Pinawa (Canada)
A {open_quotes}passive{close_quotes} CANDU{reg_sign} containment system, currently being developed, is aimed at limiting the consequences of a postulated accident, by ensuring the structural integrity of the containment building and limiting fission-product release to within siting dose limits, without operator action or reliance on ac power for up to 3 d. All main functions of the containment system, i.e. energy removal, hydrogen mitigation, and fission-product retention, are to be accomplished passively. The passive CANDU containment relies on the passive emergency water system (PEWS) for energy removal after an accident and on passive autocatalytic recombiners (PAR) for hydrogen removal. The key feature of this concept, is a recirculating, buoyancy-driven flow through the recombiners and the tube banks of the PEWS. This paper presents preliminary design calculations for the PEWS tank and tube banks and a simulation of the long-term passive containment response, based on the current CANDU-6 containment, to a large loss-of-coolant/loss-of- emergency coolant injection (LOCA/LOECI) using the GOTHIC code. It is shown that a 1500-M{sup 3} PEWS tank, connected to tube banks with a total surface area of 1800 m{sup 2}, can limit the second pressure peak to about 300 kPa(a) if a recirculating flow is established in the containment building. The PEWS tank water is boiling in the long term, and the peak containment temperature is 114{degrees}C. 6 refs., 4 figs.
- OSTI ID:
- 549115
- Report Number(s):
- CONF-970607--Vol.1
- Country of Publication:
- United States
- Language:
- English
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