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Romero, Christopher Jesse

Publications and source records attributed to Romero, Christopher Jesse.

9 records
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DOE OSTI2019

CSTT Update: Fuel Quality Analyzer

Presentation summary: A Nafion® based, electrochemical hydrogen contaminant detector was tested at H2Frontier hydrogen filling station in Burbank CA during its refit and recommissioning.; A 100 sccm sample was taken from the H2F production skid and without requiring humidification; both real-time product gas and storage gas was sampled. The selfhumidifying approach using an internal reservoir worked with minimal baseline drift.; The LANL HCD easily detected CO byproduct during reformer restart (as high as 18ppm) and 11, 1ppm challenges were performed during an 850h experiment after initial installation and 10ppm testing/commissioning.; The 10ppm and 1ppm challenges produced ≈ 75% and ≈ 60% reductions in pumping current respectively. Twelve, 1ppm challenges decreased pumping current on average of 59.5% with an error of ±1.4% over 12 challenges during a 6 month time period.; Long term baseline data show a drift rate of 9x10- 7 A/h over a 600h period of testing. The addition of a 1.5V, 600s pulse approximately once a day eliminated any long term drift.; No false positives or false negatives were seen during the field tests to date.; Average water consumption rate is estimated to be ~250μl/day at 100sccm.; Project milestones successfully met.

08 HYDROGEN↗
DOE OSTI2017

Editors' Choice—Field Trials Testing of Mixed Potential Electrochemical Hydrogen Safety Sensors at Commercial California Hydrogen Filling Stations

Hydrogen safety sensors must meet specific performance requirements, mandated by the U.S. Department of Energy, for hydrogen fueling station monitoring. Here, we describe the long-term performance of two zirconia-based mixed potential electrochemical hydrogen gas sensors, developed specifically with a high sensitivity to hydrogen, low cross-sensitivity, and fast response time. Over a two-year period, sensors with tin-doped indium oxide and strontium doped lanthanum chromite electrodes were deployed at two stations in four field trials tests conducted in Los Angeles. The sensors documented the existence of hydrogen plumes ranging in concentration from 100 to as high as 2700 ppm in the area surrounding the dispenser, consistent with depressurization from 700 bar following vehicle refueling. As expected, the hydrogen concentration reported by the mixed potential sensors was influenced by wind direction. Baseline stability testing at a Chino, CA station showed no measureable baseline drift throughout 206 days of uninterrupted data acquisition. In conclusion, the high baseline stability, excellent correlation with logged fueling/depressurization events, and absence of false alarms suggest that the zirconia-based mixed potential sensor platform is a good candidate for protecting hydrogen infrastructure where frequent calibrations or sensor replacement to reduce the false alarm frequency have been shown to be cost prohibitive.

08 HYDROGEN↗