Experimental Research Of Low Temperature Influence On The Stability Of Emulsion Explosive

China is a vast country where the climate of the south regions and north regions differs sharply, especially in the northeast, Sinkiang, Inner Mongolia and other regions, winter is long and cold. In winter Open-pit mine blasting, frozen soil blasting, vertical frozen shaft blasting, construction units found that they must heat emulsion explosives up to room temperature before initiating, otherwise easy to misfire. Not only used extremely inconvenient, and brought to the property damage and potential safety hazard to users, because unreliable initiation of the emulsion explosive. This phenomenon directly reflected that emulsion explosive was unstable and perishable in essence when it was in low temperature. Hence, it had great research value and significance for improving the performance of emulsion explosive at low temperature that to explore the impacts of low temperature on the stability of the emulsion explosive and the impact mechanism.Aiming at these problems, emulsion explosives were prepared with different sensitization methods, water formulas, emulsifiers, oil phase materials. And the impacts of low temperature on the stable performance of emulsion explosives were analyzed by controlling variable method, Tyndall method and microscope observation, the orthogonal experiment method, water soluble method and Chem3D software simulation, etc.The results showed that under the condition of low temperature:(1)Physical sensitization was better than chemical sensitization for emulsion explosive, although which makes the crystallization rate 7% higher than that of emulsion explosive sensitized by chemical sensitization, because physical sensitization was very reliable instead of most chemical bubble breakup. (2)The stability of emulsion explosives could be improved by reducing the crystallization point of water phase, when their storage time was not too long and the temperature was not too low (0℃). However it should be improved by controlling the water content at 11%, when storage both for a long time and in lower temperature (-25℃). (3) the molecular structure of emulsifier changed, the oil film broken and coalesced because of the low temperature, which led to bringing the stability of the emulsion explosive down. But the emulsion explosive had a good stability which was prepared by the compound emulsifier that composed by 90% of span-80,5% of T-152 and 5% of soybean lecithin. According to theMolecular Dynamics simulation results, the reason was that:although the molecular structure of span-80 and soybean lecithin changed at low temperature, but after variant the molecular structure of them as emulsifier is still reasonable. The composite membrane could be electrically charged when charged soybean lecithin and uncharged span-80 were compounded. Repulsion of like-charge elements prevented droplets getting close to each other in the space and aggregating, which can improve the stability of the emulsion. At low temperatures T-152’s hydrophilic group and lipophilic group were out of the three-dimensional hindrance action, because they intertwined with each other, thus adding emulsion coalescence. (4)The higher the viscosity and the surface tension of oil phase was after melting, the more stable the emulsion matrix was.The results of the study had a certain reference function for improving formulations of explosive emulsion used at low temperature, and enhancing the stability of the emulsion at low temperature in the future.