Application of Silicon Dioxide as the Inert Component or Oxide Component Enhancer in ANFO

Non-ideal explosives with differing contents of silicon dioxide (silica or dioxosilane) added in the form of powder and gel were tested. Measurements of structure, crystallinity and morphology were performed by means of infrared spectroscopy (IR), X-ray diffraction (XRD) and scanning electron microscopy (SEM). IR and XRD analysis revealed a lack of SiO2 influence on the non-ideal explosive structure. SEM analysis indicated that all the surface deformations of ammonium nitrate(V) prill were filled by a thin fuel film layer on which SiO2 was present. The additional calculations of selected theoretical properties of non-ideal compositions were made using ZMWCyw software. Based on this, it was established that the optimum semimetal content was 1.0 wt.%. Blasting tests confirmed that the addition of 1.0 wt.% SiO2 to the Ammonium Nitrate Fuel Oil (ANFO) resulted in the lowest volume of post-blast fumes. Moreover, it was established that finer SiO2 powder cannot be used as the oxide component enhancer due to the inhibition of detonation reaction. SiO2 should be used only as an inert component.

Estimating the amplitude of the pressure on the obstacle of products of an under-compressed outgoing detonation wave of a structured charge

The study relies on the concepts of various mechanisms of explosives decomposition at supersonic propagation of the under-compressed detonation reaction zones, and examines the structured charges explosion effect on compressible obstacles. In such charges, artificially or naturally, there can appear rod-like formations highly capable of detonation, penetrating the charge and ensuring the propagation of the complete heat release zone at a speed greater than the normal, and the ideal detonation speed of a monodisperse charge is of the same density. We introduce a simple algebraic model of the explosive process of structured charges, the process proceeding in the form of under-compressed detonation. We obtained algebraic expressions that make it possible to compare the peak pressures at the obstacles depending on the direction of detonation propagation relative to the obstacle and on the mode of detonation, i.e. whether it is normal or “under-compressed”.