Analysis of explosion characteristics of mixed biomass explosive based on detonator and aluminum thermite detonation

To explore the feasibility of replacing detonators with nano-aluminothermic agents in mixed biomass blasting agent systems for stable initiation and their differences in detonation performance, wood powder and peanut shell powder (1:1) were used as the core raw materials. Three initiation methods were selected: digital electronic detonators (S0), Al/CuO aluminothermic agent (S1), and Al/Bi2O3 aluminothermic agent (S2). Traditional industrial explosive performance testing methods were employed to conduct orthogonal tests on aluminothermic agent trial detonations, explosion velocity, and brisance, as well as underwater explosion and blasting crater tests to investigate their explosive performance patterns. The trial detonation tests confirmed that aluminothermic agent initiation is a typical high-temperature deflagration energy release process, featuring an extended reaction zone but high energy density, enabling effective energy coupling within limited constraints to trigger the overall explosive reaction of the biomass blasting agent, thus demonstrating reliable initiation capability. Orthogonal tests on explosion velocity and brisance revealed that oxygen pressure is the dominant factor influencing both parameters, followed by steel pipe wall thickness, while the initiation method has a relatively weaker effect. By increasing oxygen pressure and optimizing confinement conditions, synergistic enhancement of explosion velocity and brisance in biomass blasting agents can be achieved, resulting in superior explosive performance combinations. Underwater explosion tests showed that S0 exhibits higher peak pressure, impulse, and specific shock energy than S1 and S2 initiation methods, with the S2 system demonstrating better energy release and impact effects compared to the S1 system. Blasting crater tests indicated that the largest crater volume (0.33m3) was formed by S0 initiation, followed by S2 initiation (0.24m3), and the smallest by S1 initiation (0.21m3). All three initiation methods successfully detonated the mixed biomass blasting agent, with the initiation performance ranking as follows: digital electronic detonator (S0) > Al/Bi2O3 aluminothermic agent (S2) > Al/CuO aluminothermic agent (S1). This study provides experimental support for the optimization and application of biomass blasting technology.