Suppression chemistry of water mists on diffusional flames

摘要

It is well-known that fire suppression by water mist is mainly based on physical effects such as heat extraction through evaporation, oxygen displacement, and attenuation of thermal radiation. However, there might be chemical inhibition effects which are not clearly understood. Chemical kinetics associated with the interaction of water with flames should be studied, but the reaction chemistry depends on the flame to be suppressed. It would be very interesting to investigate the suppression chemistry of water mist on burning different fuels of polymers. Suppression chemistry of water mist on diffusion flames from burning different fuels will be reviewed first. Homogeneous interaction of water with gas fuel in the combustion will then be discussed. Heterogeneous oxidation of carbon in the existence of water will be briefly introduced. The kinetics and mechanisms of selected reactions involving hydrogen (H), carbon monoxide (CO), carbon-based fuels (C), and small hydrocarbons such as methane (CH 4) will also be discussed. Those are considered key combustion reactions which can provide useful information for understanding burning polymers. Note that polymeric materials have been widely used in modern buildings. Fire safety associated with burning plastics is a great concern. In such interaction reactions, water is taken as interacting with the flame by converting the oxygen (O) radicals to hydroxyl groups (OH). These products would have direct involvement in the water-gas reaction system by acting as efficient collision partners in the chemical kinetics of the combustion reactions.