(189bl) Characterization of Heat Absorption and Decomposition Products for Suppressant Agent/Combustible Dust Mixtures Via TGA/DSC/MS Analysis

Combustible dusts continue to present a critical threat towards personnel and process equipment in a wide variety of bulk solids processing industries. Addition of non-combustible inert material to combustible dust mixtures, either through pre-mixing or injection as the deflagration begins to develop, is common practice for preventative inhibition or explosion protection (mitigation) via active suppression, respectively. Metal dusts specifically present an extremely reactive explosion risk due to characteristically augmented heats of ignition, burning temperature, flame speed, explosibility parameters (K_St and P_max), and ignition sensitivity. Establishment of proper prevention and protection designs for metal fuels has posed challenging. The aim of this paper is to propose a method for the characterization of the inhibition efficiency of six suppressant agents (sodium bicarbonate [SBC], potassium bicarbonate [PK], monoammonium phosphate [MAP], diammonium phosphate [DAP], potassium allophanate-based [Agent ‘Z’], and sodium chloride-based [Met-L-X^TM]) when mixed with fuels of both organic (cornstarch) and metallic (zinc) nature. For each 1:1 wt% fuel/agent mixture, thermal stability and heat absorption efficiency have been evaluated through thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC).