Testing a Passive Autocatalytic Recombiner in the Surtsey Facility

Performance tests of a scaled passive autocatalytic recombiner (PAR) were performed in the Surtsey test vessel at Sandia National Laboratories. Measured hydrogen depletion rate data were obtained and compared with previous work. Depletion rate is most likely proportional to PAR scale. PAR performance in steamy environments (with and without hydrophobic coating) was investigated. The tests determined that the PAR startup delay times decrease with increasing hydrogen concentrations in steamy environments. Tests with placement of the PAR near a wall (as opposed to a center location) yielded reduced depletion rates. Tests at low oxygen concentrations also showed a reduced recombination rate. The PAR repeatedly ignited hydrogen at ~6 mol% concentration with a catalyst temperature near 940 K. Velocity data at the PAR exhaust were used to calculate the volumetric flow rate through the PAR as a function of the vessel hydrogen concentration.