Inhibition of hydrogen-air explosions by dry water modified by ammonium salts

This paper describes an experimental study of the inhibiting effect of dry water (DW) modified by ammonium salts on hydrogen-air explosions. The experiments were conducted in a 20-L explosion vessel with mixtures of 15 vol% hydrogen in air, using four inhibitors: (i) ammonium dihydrogen phosphate (ADP), (ii) diammonium phosphate (DAP), (iii) ammonium bicarbonate (AB), and (iv) ammonium carbonate (AC). The results show that all inhibitors effectively reduce the maximum explosion pressure and the maximum rate of pressure rise. ADP-DW has the best inhibition performance, reducing maximum rate of pressure rise by 56% at 500 g/m 3 . Kinetic analysis indicates that the addition of modified DW reduces the concentration of active radicals. The inhibiting effect is governed mainly by physical effects in the investigated conditions, while ADP-DW exhibits stronger chemical effects due to phosphorus-containing intermediates. This research provides valuable experimental data supporting further development of chemical inhibition technologies for hydrogen-air explosions.