Research On Risk Assessment Of The Continuous Typical Double-base Spherical Propellant Process

Propellants provide energy for the launch of gun barrel,but their production processes are numerous,and materials are flammable and explosive,so the risk of burning and explosion in their life cycle.When an accident occured,it caused huge property losses and casualties.The risk assessment of a continuous spherical propellant process provides a reference for the safe production of propellants.Firstly,hazardous factors in the spherical propellant process were identif ied from the aspects of raw material,process,equipment and operating environment,the thermal decomposition characteristics of the double-base absorbent powders with the decreasing water content were studied through DSC and ARC tests.The Kissinger method and Friedman method were used to calculate thermal decomposition kinetic parameters and predict thermal safety parameters.Research shows that,the inherent fire and explosion hazards of materials may cause accidents under the action of stirring,cutting,friction and heat,and the crowded workshop will increase the severity of the accident;when the double-base absorbent powders decompose,their dynamics are complex,and they release a lot of heat,which is greater than 3900 J/g,and the initial decomposition temperature is about 169°C.And the double-base absorbent powders with a water content of 12%is the most dangerous,its SADT is 90°C and T_D24 is 105°C.Secondly,the indicators to identify the key processes in the spherical propellant process were obtained by the text mining technology,then the key processes were obtained by the information entropy-TOPSIS method.According to the research,the seven indicators for identifying key processes are equipment status,accident loss,accident impact,parameter monitoring,material characteristics,accident probability and protection design.The key processes are extrusion,pelletizing,plasticizing and desolvation process in the spherical propellant process.Finally,by employing HAZOP-LOPA-SIL method,the potential hazards in the extrusion process and the desolvation process were identified and their causes and consequences were found,and the effectiveness of the independent protective layer were evaluated and the security integrity level of added protection layer were determined.The results show that there’re a total of 6 dangerous scenarios in the two processes,the three scenarios of"excessive process temperature","excessive screw speed"and"excessive pressure"need to add automatic emergency stop systems and low temperature alarm systems,and the safety integrity level is both level 2.