Manager—Explosion Technology Group, Graviner Ltd., Colnbrook, Slough
Pages: 13 Published: Jan 1987
The results of a systematic series of maize (corn) dust explosion suppression trials in vessel volumes of 6.2, 10, and 25 m3 are presented. Tests are reported for explosions of both medium and high turbulence dust clouds. The four suppressants, Halon 1011, ammonium phosphate powder, water, and halon/powder hybrid, were tested. The ammonium phosphate powder proved to be significantly more effective than the other suppressants. In the case of highly turbulent maize dust explosions, the halon suppressant catastrophically failed to suppress the incident. Suppression effectiveness is shown to be more dependent on the speed of deployment of the suppressant agent than on the absolute concentration delivered into the vessel. Thus, deployment of suppressant from a larger number of smaller suppressors results in a lower suppressed explosion pressure. The criteria for the limits of effectiveness of a given suppression system are defined and the experimental results compared with a theoretical estimate of the expected suppressed explosion pressure. It is shown that there is a reasonable correspondence between the theoretical estimate and corresponding experimental measurement and concluded that a theoretical model can be used as a basis for the design of effective explosion suppression systems for industry.
dust explosions, explosion protection, explosion suppression, suppressants, maize dust
Paper ID: STP28180S