Core-Melt Source Reduction System (COMSORS) to terminate LWR core-melt accidents

Conference · Tue Dec 08 04:00:00 EST 1992

OSTI ID:10122072

Forsberg, C W; Beahm, E C; Parker, G W

One of the design, safety, and licensing issues for the next generation of light-water reactors is this: What approach should be used to terminate a reactor core-melt accident and ensure no reactor containment failure in the unlikely event of an accident that results in core debris upon the containment floor? The safety concerns are that the debris will (1) melt through the concrete floor (thereby penetrating the containment) and (2) generate noncondensable/burnable gases (thus pressurizing the containment and threatening its integrity). Noncondensable gases include burnable hydrogen and carbon monoxide, generated primarily from the reaction of zirconium with concrete decomposition products (water and carbon dioxide). A new approach to eliminate these concerns is being developed. The basic concept of the Core-Melt Source Reduction System (COMSORS) involves placing glass under the reactor vessel. If molten care material is released onto COMSORS. the following happens: (1) the glass absorbs decay heat for hours as its temperature increases and the glass softens; (2) the uranium and fission-product oxides dissolve in the molten glass, thus creating a ``uniform`` high-level waste (HLW) glass: (3) the molten HLW glass spreads into a wide pool, uniformly distributing the heat for removal by radiation to the reactor cavity above or transfer to water on top of COMSORS: (4) the pool materials will be molten and convective at temperatures near 1000{degrees}C, a sufficiently low temperature that surrounding concrete can be practically protected; and (5) the HLW glass solidifies as increased surface cooling allows heat removal to exceed heat generation. This process converts core debris of uncertain composition and geometry that may be uncoolable into a relatively uniform glass composition with known properties in a coolable geometry.

• Research Organization: Oak Ridge National Lab., TN (United States)
• Sponsoring Organization: USDOE, Washington, DC (United States)
• DOE Contract Number: AC05-84OR21400
• OSTI ID: 10122072
• Report Number(s): CONF-930352--12; ON: DE93006219
• Country of Publication: United States
• Language: English

Related Subjects

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS
210100
210200
22 GENERAL STUDIES OF NUCLEAR REACTORS
220900
BWR TYPE REACTORS
CONTAINMENT SYSTEMS
COOLING
CORIUM
ENCAPSULATION
GLASS
HEAT TRANSFER
HYDRAULICS
MELTDOWN
POWER REACTORS
NONBREEDING
LIGHT-WATER MODERATED
BOILING WATER COOLED
POWER REACTORS
NONBREEDING
LIGHT-WATER MODERATED
NONBOILING WATER COOLED
PWR TYPE REACTORS
REACTOR SAFETY
VITRIFICATION