Study into influence of different types of igniters on the explosion parameters of dispersed nitrocellulose powder

Abstract

Nitrocellulose is a flammable compound produced by cellulose nitration. The nitrocellulose production and handling are associated with a risk of fire and explosion. Nitrocellulose is used as either collodion cotton (<12.5% N) or as an explosive (>12.5% N). Nitrocellulose is a fibrous or powdered substance and may detonate or burn upon certain conditions. The article compares the combustion parameters of dry nitrocellulose in the KV-150M2-UIBE explosion chamber at the concentrations of 250, 500 and 750 g m−3. To ignite a nitrocellulose sample, six different types of igniters were used. A commercially available 5 kJ pyrotechnic igniter was used as the standard. Also used were a nitrocellulose igniter, a pyrotechnic igniter with magnesium powder and KNO3/KClO3, and an exploding wire (Kanthal and tungsten wire). The examined igniters were found to affect the explosion parameters of dispersed nitrocellulose. The deviation of the explosion constant Kst reached 50% of the standard value. The highest pressure of 12.73 bar g was reached at a concentration of 750 g m−3 and an igniter exploding wire with Kanthal wire. The highest Kst value of 287.9 bar.m.s−1 was achieved at a concentration of 750 g m−3, when using the pyrotechnic igniter with KClO3 and magnesium powder.