Pryadko N. Improving of a fluidized bed fence for gasdynamic motion of material

Thesis of Phi. D. in technical sciences on the speciality 05.14.06 - technical thermal physics and power industry. - National Metallurgical Academy of Ukraine, Dnepropetrovsk, 2004. This thesis is devoted to development of the flow method for lower-grade coal burning in fluidized bed. The new vane-slot grate modification has been developed and the method of lower-grade coal burning in flowing fluidized bed with ash-and-slad gasdynamic removal has been proposed. The main hydrodynamic characteristics of grate and bed over it were determined. The offered mathematical model of flowing fluidized bed was based on the Kolmogorov-Fokker-Plank's equation solution. The possibility of the numerical-analytical simulation of the decrease of the coal combustible fraction in this type of a fluidized bed was shown. The hydrodynamic similarity factors are defined in order to use the cold model results for full-scale device. The new improved vane-slot grate has experimentally proved fixed advantages: turning of themovable vanes allows to control coal loading and unloading process, it provides an even coal distribution over the grate, allows to create the flowing fluidized bed, to produce various types of fluidized bed. This grate has low hydraulic resistance, has no dead and slagged zones. The process flowsheet of lower-grade coal burning in flowing fluidized bed has been proposed. It includes the direct incineration of coal particle in flowing fluidized bed over the vane-slot grate, catching the unburned coal particles by the screw type cyclone, returning them into the furnace and the final cleaning of the flue gas after the cyclone using the emulsifier. The recommendations for improvement of the technological devices were proposed.