Study on the Effect of Shale Solid Waste-Based Composite Powder Explosion Inhibitor on the Inhibition Characteristics of Poplar Wood Powder Explosion

This study deals with the risk of controlling poplar dust explosions in the woodworking industry. First, solid waste shale ash (SA) from an oil shale refinery was pretreated via acid-alkali modification to obtain a porous modified shale ash (MSA) carrier. Then KOH and Al(OH)3 were loaded onto the modified material via solution impregnation and low-temperature calcination, yielding a shale ash-based composite powder that features a crystalline-amorphous composite structure, denoted as MSA-Al2O3-KCl. The performance of the composite inhibitor in suppressing poplar dust explosions was evaluated using a 20-liter spherical explosion vessel and a transparent pipeline system. The results demonstrated that the prepared composite inhibitor significantly reduced the explosion pressure; at a 30% additive dosage, the maximum explosion pressure decreased by 56.3%. At a 50% dosage, the flame propagation speed was reduced by 91%. As a porous carrier, MSA provides physical encapsulation and thermal dilution effects for dust particles; highly dispersed amorphous alumina catalyzes directional pyrolysis and solid-gas phase separation; while the chemical conversion of crystalline potassium chloride and the removal of gas-phase radicals direct the reaction pathway toward the formation of more stable explosive products. The MSA-Al2O3-KCl formulation offers a solution for preventing poplar dust explosions and provides an innovative approach for the environmentally friendly, low-carbon management of industrial solid waste.