As an oxygen carrier and a strong oxidising agent, ammonium nitrate can create an explosive mixture when mixed with organic material. A typical example is the mixture of ammonium nitrate and fuel oil (ANFO), which is the most used explosive for civilian applications. In this work, we studied the detonability and detonation properties of mixtures of ammonium nitrate with recycled rubber and hay. The main goal of this study was to determine the optimal volume ratio of ammonium nitrate and organic materials in terms of achieving the best performance (working capacity). Using small experiments, it was determined that the maximum burst velocity for the ammonium nitrate/hay mixture is achieved at 8% hay by volume, while the maximum burst velocity for the ammonium nitrate/rubber mixture is achieved at 15% rubber by volume. A thermochemical calculation has shown that the maximum detonation heat is achieved at the zero oxygen balance at the volume ratios of 89.2/10.8 for AN/Rubber and 72.85/27.15 for AN/Hay.
Low-density emulsion explosives are essentially blends of an emulsion matrix and a certain amount of gaseous phase inclusions acting as hot spots. With the addition of expanded polystyrene for gaseous sensibilization, the resulting explosive blend was developed to reduce peak values and pressure impulse of gaseous detonation products on surrounding rock. This resulted in a decrease in rock stress and a decrease in cracking zone width outside of the minefield boundary. The use of low-density emulsion explosives correlates with the decrease in the seismic effect of blasting, more precisely, the decrease of induced rock oscillation velocities. The low-density emulsion explosive used in this work was validated based on laboratory and field experiments. The laboratory experiments measured dominantly detonation and safety characteristics, while field experiments characterized working capacity, i.e. single-shot blasting effect in an igneous diabase. The obtained measurements were compared against reference explosives (pentrite, emulsion explosive sensitized with glass microspheres, and ANFO explosive). Measured parameters were detonation velocity and oscillation velocity used to determine the seismic effect of blasting in the immediate borehole vicinity.
1 January 2018 in Rudarsko-geološko-naftni zbornik
Using the energy of explosion, a print of the picture "Medieval mine" onto an aluminium plate was made. This is one version of a technique called Detonography. It has been introduced and developed by Evelyn Rosenberg with a number of her colleagues, based on the "Munroe effect". To determine the optimal parameters of explosive performance and supporting materials, a large number of laboratory testing has been made on smaller samples.