الفهرس 
CHAPTER ONE : INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Increasing in world population leads to producing a huge amount of solid wastes, therefore, generating energy from wastes has been demanded to find new inexpensive energy sources due to the rise in the price of fuels. Fluidized bed reactor (FBR) is well known as an adequate technology for burning solid fuel due to its many apparent advantages. An experimental study comprising four parts on a proposed gas-solid -cold flow- swirling fluidized bed reactor, SFBR, is presented. Firstly, a parametric study of the heat transfer from wall to bed and bed flow dynamics in a SFBR with annular blade distributor were investigated. The investigation was at different designs and operating conditions, mainly a number of blades, using gas plenum, and using gas plenum with different central bodies. The reactor surface was heated using three heaters located at equal distances along reactor circumference. The results showed that increasing number of blades from seven blades with an inclination angle of 45o to twelve blades with an inclination angle of 12o resulted in decreasing the distributor and bed pressure DROP and increasing the heat transfer coefficient, HTC, which means enhancing the overall operation of the reactor. The results also showed that utilizing gas plenum before the distributor leads to decreasing the distributor and bed pressure drops, and hence, to decreasing the required power. However, it results in decreasing the HTC at all different values of air velocities. The results also showed that utilization of central bodies either conical or cylindrical shapes in center of the plenum resulted in a negative effect due to increasing the distributor and bed pressure drops and decreasing the HTC. Secondly, the bed to wall heat transfer process and bed flow behavior of a bed particles mixture in a swirling fluidized bed were studied. Two different bed materials -sand with a mean size of 1.5 mm and Polyethylene (PE) beads with a diameter of 6 mm- were used. The influences of inlet air velocity, bed height and mass fraction of PE beads upon heat transfer exchange between hot inlet air and walls have been studied. The results showed that both minimum fluidization and minimum swirling velocities -which measured at a different mass fraction - increased by increasing the quantity of PE beads. The results also showed that increasing PE beads mass fraction resulted in decreasing HTC and increasing the bed pressure drop. The results also showed that the HTC is affected by the height of the bed, as the HTC decreases with increasing height. The results also showed that using a central metallic cone enhances both fluidization behavior by decreasing bed pressure DROP and heat transfer process by increasing the HTC. Thirdly, the differences between conventional fluidized bed reactor (CFBR) and SFBR have been investigated experimentally with respect to the fluidization behavior and the heat transfer exchange between the immersed heater and the bed. Then, the effects of particle diameter on bed flow and heat transfer in swirling fluidized bed were studied. The results showed that the pressure DROP across the air distributor and the bed in case of SFBR were lower than those of CFBR and this characterizes SFBR. The results also showed that the HTC in case of SFBR was higher than that of CFBR at lower bed regime but at the upper regime, it was lower. This behavior can be interpreted as at lower bed heights the bed particles were at full swirl state that improves the heat transfer process. However, the swirl action decreases gradually with increasing bed height. The results also showed that the HTC increases with reducing particle size, however, the bed pressure DROP also increases too. Also, it was found that the HTC was higher in lower bed height than that of upper bed heights for the two different particle sizes. Fourthly, a novel rotating air annular blade distributor have been studied concerning with heat transfer and hydrodynamic characteristics of the bed. The rotating swirling fluidized bed reactor was compared to a fixed swirling fluidized bed reactor with respect to heat transfer and bed hydrodynamics. The heat transfer process between bed and wall in a SFBR was studied. Air was preheated before entering the reactors by two electrical heaters. The results showed that both distributor pressure DROP and bed pressure DROP for the rotating distributor are lower than the fixed one. The results also showed that the rotating air distributor results in enhancing the heat transfer process (since HTC increases) compared to a fixed one. The results also showed that increasing the rotating speed of the distributor improves the operation of the reactor by decreasing bed pressure DROP and increasing HTC.