Studies On Energy Improvement And Energy Output Structure Of Emulsion Explosives

Emulsion explosives have become the dominant specie of industrial explosivesin china due to its wide range of raw materials, low cost, anti-water，simpleproduction process. However, the low detonation energy, which is caused by about10%water in its composition resulting in the effective combustible component ratiodecreasing, limits the application of emulsion explosives in blasting field. In addition,it is also one of important research topics to adjust the energy structure forimprovement of energy utilization of explosives and blasting effects. In order toimprove energy and energy utilization of emulsion explosives, tentative studies arecarried out in terms of the experimental and numerical methods.Formular of emulsion explosives with the oxygen balance of-0.0005wasdetermined. The effects of Al content and particle size on detonation properties ofemulsion explosives were considered in term of experimental results of detonationvelocity, detonation pressure and brisance, as well as the calculative results of Gurneyenergy and Gurney velocity. In addition, the relation between Al on the thermalstablility of emulsion explosives was obtained using the C80micro calorimeter. Theresults showed that Al could participate in the reaction in the detonation zone, whichimproved the detonation velocity and pressure of enlusion explosives. The reactionhappening outside ethe detonation zone would increase the brisance and ability toperform of emulsion explosives.The effects of charging on the energy output structure of emulsion explosiveswere studied in underwater explosion using a small pool. Decoupling charging wasdesgined that was suitable for a small pool for the first time, and the underwaterexplosion energy of emulsion explosives with decoupling medium and deouplingcoefficent were determined. The effects of deoupling coefficient, decoupling medium,Al content and oxygen balance on the type and structure of energy output foremulsion explosives. The results showed that the explosion energy exhibited aobvious decay with the increasing of deoupling coefficient. Smaller energy decay wasfound in case of water decoupling medium. Both shock wave and bubble energy couldincrease with increasing content of aluminum powder. JWL equation of state of emulsion explosives was dertinmined based on theGibbs minimum free energy principle. The radial and axial decoupling chargingmodles was established using AUTODYN software. The effects of radial decouplingcharging on the underwater explosion energy and energy utilization efficiency werenumerically studied. The effects of air column position and stemming material on thedamage distribution in case of axial decoupling charging were obtained. Hence theenergy utilization efficiency was finally determined. The results showed that thelarger damage zone was observed when water medium was adopted, which indicatedthe higher energy utilization efficiency. Moreover, the damage was more evenlydistributed when the air column was palced in the middle. In addition, higher energyutilization efficiency was seen when concrete was used as the stemming material.