Comparison of flame propagation properties of petroleum coke and coals of different rank

Fundamental Experiments of Coal Ignition for Engineering Design of Coal Power Plants

“…Object of this chapter is to develop a model to predict lean flammability limit and flame propagation velocity for pulverized solid fuels, and to apply the model to engineering design for burner systems. Figure 3 shows a schematic of the laser ignition equipment [10][11][12]25]. Uniformly sized pulverized coal particles were suspended in a laminar upward flow and rapidly heated by a single-pulsed YAG laser.…”

“…When coal concentration was high; almost the same as that for actual systems, the flame moves from the particle directly heated by the pulsed YAG laser to neighboring particles; in this way the flame grew. We defined these phenomena as flame propagation [11,25]. Only particles directly heated by the pulsed laser burned when the coal concentration was low.…”

“…Data on bituminous coals and anthracites of the same particle diameter were obtained under various burning conditions [12], and the effect of particle diameter was examined [11,25]. Relationships between L, Sb-max and particle diameter Dp are summarized by Eqs.…”

“…Figure 9 shows the lean flammability limit L at the same diameter with different volatile contents of coals. The evaluation method of lean flammability limit has been shown elsewhere [11,25]. The vertical axis of Fig.…”

“…Examples of pyrolysis calculations for various fuels are shown in Fig.10. The calculation method has been shown elsewhere [24,25]. The relationship between heating time and amount of pyrolized volatile matter was calculated when the particle was heated at a rate of 20000K/s.…”