Hydrogen recombination in safety containment for nuclear power plant - promoted by continuous convective circulation of atmos. to prevent local concns.

摘要

A nuclear power plant is surrounded by a safety containment in which a recombination appts. carries out controlled oxidn. of free hydrogen to prevent excess build-up of hydrogen, esp. in a fault case. Vertical shafts inside the safety containment extend over at least half the height of the containment and comprise heaters for producing a convective circulation of gas. Pref. these heaters serve also as thermal recombination units. In a pref. arrangement the shafts extend from a position near the bottom of the containment into the top zone. Used for any reactor system where hydrogen can be produced by radiolysis of water in the core in the case of loss of coolant, or in the sump of the cooling pool. The arrangement enables full circulation to be maintained inside the containment without mechanical pumps and similar devices and thus prevents local build-up of hydrogen above the safety level of approx. 4% by vol.