The technology of suppression containment for the SMR in floating nuclear power plants against hydrogen risk

Abstract

In the event of loss of coolant accident (LOCA) in small modular reactors (SMRs) in floating nuclear power plants (FNPP), appropriate pressure suppression and hydrogen elimination measures must be taken to ensure small modular reactors' safety. This paper utilizes GASFLOW to analyze the environmental conditions and gas behavior following the implementation of pressure suppression and hydrogen elimination measures in SMRs. The results indicate that: 1) The suppression effect is optimal when the capacity of the suppression pool is 200 m3 and the gas–water ratio is 2.33. 2) When passive autocatalytic recombiners (PARs) are used alone, hydrogen can’t be eliminated quickly, and there is still a hydrogen explosion risk in the containment. 3) Using igniters alone can effectively reduce the hydrogen risk. 4) The combination of PARs and igniters can safely and efficiently eliminate the hydrogen risk, and the temperature inside the containment is lower than when the igniter is used alone.