Study On Thermal Behavior And Thermal Hazard Of Emulsion Matrix Containing Iron Ion Under Different Heating Conditions

In recent years,there have been many major explosion accidents of emulsion explosives.The investigation found that the mixing of some impurities during production and transportation will promote the thermal decomposition of emulsion explosives,and the content of iron ions(Fe³⁺)is the highest.In order to understand the thermal behavior and thermal hazard changes of the emulsion matrix containing Fe³⁺under different heating conditions,so as to prevent the occurrence of thermal explosion accidents of emulsion explosives,combined with previous research results and actual production conditions,and a series of pre-preparation experiments were carried out,four emulsion matrix samples containing 0.00%,0.04%,0.08%,and 0.10%Fe³⁺were prepared in this paper.The thermal decomposition characteristics of the four samples were tested by DSC and ARC,and the kinetic parameters such as activation energy and pre-exponential factor in the thermal decomposition process were calculated.Based on this,a series of thermal hazard parameters were solved.The thermal hazard situations and levels were identified,and the thermal resistance and thermal stability of the four samples were tested by constant temperature pyrolysis experiments and thermal stability experiments.The following conclusions were reached:（1）In the linear temperature rise test of DSC,Fe³⁺will reduce the initial decomposition temperature of the emulsion matrix and increase the peak temperature,which is more significant at low concentrations.Activation energy calculation results show that Fe³⁺reduces the energy required in the initial reaction of the emulsion matrix,and the reaction mechanism changes from three-dimensional diffusion to random nucleation and subsequent growth.Compatibility evaluation results show that the more Fe³⁺content in the emulsion matrix,the worse the stability.（2）In the adiabatic test of ARC,Fe³⁺will not only advance the thermal decomposition process of the emulsion matrix and increase the adiabatic temperature rise,but also cause it to release more gas products,causing the temperature and pressure in the system to rise sharply.In addition,Fe³⁺will shorten the The adiabatic induction period of the runaway decomposition reaction reduces the SADT under certain packaging conditions,which reduces the thermal stability of the emulsion matrix.This effect will be weakened when the Fe³⁺concentration is high.When the Fe³⁺concentration is 0.04%,the adiabatic onset decomposition temperature of the emulsion matrix is 220.11℃,and the SADT is 126.99℃.Using the above results to conduct thermal risk assessment,the results show that it is necessary to take measures such as changing the production process,so that the risk of emulsion matrix in production and application is at least in the"ALARP zone"and above.（3）The constant temperature pyrolysis experiment shows that the increase of the ambient temperature will significantly improve the effect of Fe³⁺on the thermal decomposition of the emulsion matrix,making the heat resistance worse.The mixed systems of the three Fe³⁺and emulsion matrix did not have obvious heating effect in the constant temperature experiment of Dewar flask at 100℃and 120℃,indicating that they meet the thermal stability standard of dangerous goods transportation.Figure[21]Table[24]Reference[85]...