Development of Hydrogen Sensors and Recombiners

Hydrogen energy is very promising, as it ensures a high efficiency and ecological cleanliness of energy conversion. The goal of the present work is to provide the analysis of hydrogen safety aspects and to prescribe methods of safety operation with hydrogen. The authors conducted a hazard analysis of hydrogen operation and storage in comparison with other fuels. Good ventilation is the main hydrogen operation requirement. Besides, an effective way of protection against propagation of hazards (for instance, leaks) is neutralization of dangerous hydrogen-air mixtures by a method of controlled catalytic combustion inside special devices, so-called recombiners [1-3]. The basis of these devices is a high porosity cell material (HPCM), activated by platinum deposition. Apart from recombiners, HPCM was also applied for development of hydrogen detectors intended for measurement and analysis of hydrogen concentration for hydrogen-driven transport and objects of hydrogen infrastructure (including vapor-air media at high pressure and  temperatures). A system of hydrogen safety based on hydrogen detectors and hydrogen catalytic recombiners was developed. Experimental and theoretical studies of hydrogen combustion processes, heat- and mass transfer, and also gas flows in catalytic-activated HPCM, allowed for a design optimization of recombiners and their location. Pilot hydrogen detectors and hydrogen catalytic recombiners were fabricated and their laboratory tests were successfully performed. Thus, it was indicated that on condition of following the  appropriate passive and active safety measures, hydrogen is just as safe as the other fuels. This conclusion represents another incentive for a transition to the hydrogen energy.