Application of response surface methodology for the preparation of modified dry water and evaluation of its explosion suppression performance

A modified dry water formulation was developed to improve flowability and reduce water loss during storage. The material was prepared by combining hydrophobic fumed silica and deionized water with super absorbent polymer (SAP), medium-chain triglycerides (MCT), and potassium chloride (KCl) as functional modifiers. Response surface methodology was used to optimize the formulation by analyzing the effects of SAP, MCT, and KCl on bulk density, flowability, and water retention. Explosion suppression tests using a 20 L spherical chamber showed that while conventional dry water reduced peak explosion pressure from 0.723 MPa to 0.620 MPa, the modified version achieved a further reduction to 0.498 MPa and prolonged the time to peak pressure from 0.13 s to 0.35 s. SEM analysis confirmed improved particle morphology and dispersion, promoting stable dust cloud formation. Thermogravimetric analysis demonstrated enhanced water content and thermal stability. Based on thermal explosion theory and chain reaction mechanisms, the modified dry water exhibits dual suppression effects: physical suppression via endothermic decomposition and oxygen dilution, and chemical suppression through radical scavenging by K· and KOH. These results suggest that the modified dry water is a promising particulate material for gas explosion mitigation in coal mining and other hazardous environments.