Synergistic suppression effects of flame retardant, porous minerals and nitrogen on premixed methane/air explosion

A novel composite inhibitor based on porous mineral materials and conventional flame retardant of ammonium polyphosphate (APP) is prepared to suppress the premixed methane/air explosion. Taking advantages of gas and powder inhibitor, N2 and the prepared composite inhibitor are combined to use. The suppression performance of N2-composite inhibitor on methane explosion is investigated on a 20-L spherical experimental explosion apparatus and the characteristic pressure data are obtained. The combined inhibition effects of N2 and the prepared composite inhibitor are greater than either acting alone. Thermal decomposition behavior and gaseous products of composite inhibitor are analyzed with thermogravimetric analysis and thermogravimetric-mass spectrometry, respectively. Based on physical and chemical actions, the inhibition mechanisms of N2-composite inhibitor system are proposed. This work provides a reference to prepare high-performance gas explosion inhibitor based on the synergism of binary or multiple components.