| OCR Text |
Show calculate the degree of carbon gasification and oxidation. 3. EXPERIMENTS The experiments were divided into two parts: the cold flow (fluidization) experiments and the hot flow (combustion) experiments. 3.1 Fludization Experiments Sand was used as the bed material. ASTM standard sieve analysis (E-ll Test) was performed to determine the particle size distribution of the sand. Table 2 shows that the diameter of most of the particles of bed material has a value of approximately 500 m. The minimum fluidization velocity (U f) was experimentally determined. Fluidization is said to be achieved when the pressure drop across the bed becomes constant with increase of air flow through the bed. The minimum fluidization velocity was experimentally determined to be 35 cm/s (6.38 1/s, 810 FPH). The theoretical calculations based on the following formula shows a good agreement with the experimental values. 0 .d-JL{„ (33.7)2 x °-°408d p X Ps (Ps ' V9] ' ] " 33*7} mf,t P Ps 1 (mean particle diameter, cms) P " I /d r x. p. I I x. = weight fraction l 3 p = density of solid, g/cm s 3 p = gas (air) density, g/cm 9 U = absolute viscosity, gm/cm-s 2 g = gravitational acceleration, gm/sec The theoretical calculations based on the following formula shows a good agreement with the experimental values within an error of about 7%. 2.4.12 |
