Passive Auto-Catalytic Recombiner(PAR)

DESCRIPTION PAR is used to protect reactor containment building from hydrogen explosion by eliminating hydrogen that might be generated during Design Basis Accident(DBA) and Beyond Design Basis Accident(BDBA). OPERATING PRINCIPLES PAR modules deplete hydrogen from the atmosphere surrounding PAR by reaction of hydrogen with oxygen on the surface of catalyst to form steam without initiation of hydrogen combustion. Hydrogen- oxygen catalytic reaction is an exothermic reaction which results in a temperature increase in PAR and then spontaneous convection flow. Thus, PAR operates by this convection flow without any external driving forces and electrical sources.



  • Honeycomb shape catalysts leading to higher hydrogen removal rate, and at the same time, to prevention of hydrogen combustion initiation.
  • Roof with eaves to avoid the inflow from LOCA(Loss Of Coolant Accident) spray.
  • Simplified installation and removal of catalysts without reassembling and disassembling.
  • Standardized supports for simplified and easy installation at site.
  • Outflow guide plate to lower flow resistance.
  • Mechanical design to maintain structural integrity against operation basis earthquake(OBE) and safe shutdown earthquake(SSE).
Model Physical Configuration H2 Depletion Rate(kg/hr)
Wt(kg) Size(mm) No. of Catalyst 4 vol.% 8 vol.%
KPAR-40 36 335×340×1400 4 1.21< 2.42<
KPAR-80 59 639×340×1400 8 2.42< 4.84<
KPAR-100 71 794x345x1400 10 3.02< 6.05<
KPAR-160 124 1276×342×1400 16 4.84< 9.68<
KPAR-200 155 1587x345x1400 20 6.05< 12.10<

ADDITIONAL EQUIPMENTS KNT supplies additional equipments with needs or requirements of the customers for maintenance and inservice inspection of catalysts.

  • Inservice Inspection Equipment(IIE): It is used to test of catalyst for inservice inspection
  • Catalyst Recovery Equipment(CRE): It is used to recovery of catalyst for maintenance

PAR installation at site