Propagation of laminar pulverized coal-air flames

Overall characterization of cork dust explosion

“…The stabilization of this maximum rate of pressure rise is related to the stabilization of the burning velocity for high dust concentrations [16]. The decrease of the burning velocity is related with the delay of the devolatilization process.…”

“…For high dust loadings, conditions when the maximum for the explosions parameters are obtained, the devolatilization process cannot be completed within the flame front, and the larger is the particle, the greater is the undevolatilized dust mass fraction [6,16]. This increase, plus the increase of the residual char makes no contribution to the flame propagation process and begins to absorb a larger fraction of the flame released heat flux, quantified by S u cρ(T b − T u ) [20], where S u is the velocity of the flame front, c and ρ are the specific heat and the density of the gas, respectively, and T u and T b are the unburned and burned gas temperatures.…”

A model of the combustion of a single small coal particle using kinetic parameters based on thermogravimetric analysis

“…Clearly, the rather long burning time of the volatiles reflects the slow liberation rate of these, as determined by the TGA experimental tests. Smoot et al (1977) and Solomon (1986) determined pyrolysis times of 0)05 s and 0)064 s, respectively, at heating rates of the order of 10 K s\, at ambient temperatures of 1000 K and for particle sizes of 30 and 53-74 m, respectively, at which time this model predicts about 45% removal of volatiles.…”

Mathematical modeling of heterogeneous detonation in gas suspensions of aluminum and coal-dust particles

“…Thus, the reaction rate at the stage of combustion is assumed to depend on the mean particle temperature. The volatile emission kinetics under conditions of rapid heating is described by the equation and constants of the corresponding reaction of pulverized bituminized coal (Pittsburg stratum) derived in [10]. The process of surface combustion is described by an Arrhenius-type equation with allowance for incomplete combustion associated both with the presence of non-combustible slags (ashes) and with the lack of the oxidizer in situations where the coal-dust concentration exceeds the stoichiometric limit [4].…”