الفهرس 
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Abstract
Chemical- Looping Combustion (CLC) has emerged as a very promising combustion technology for power plants and industrial applications with inherent CO2 capture. CLC avoids the energetic penalty present in other competing technologies. The technology basis is to transfer oxygen from air to the fuel by means of a solid oxygen-carrier avoiding direct contact between fuel and air. It consists of two successive reactions, oxidation and reduction, in two interconnected fluidized beds. The aim of the current work is to enhance the oxidation process by applying jetting fountain fluidized bed. A jetting fountain fluidized bed reactor has been designed, fabricated and installed to carry out the experimental work. It has 105 mm ID and 4000 mm height. Activated ilmenite has been used as oxygen carrier. During the tests atmospheric air is fed through an ilmenite bed that reacts with oxygen. The oxygen concentrations are measured after the bed to estimate the quantities of oxygen that combined with bed materials. The influences of operating conditions including bed temperature, fluidization velocity, jet air ratio and jet orifice height on the process effectiveness have been studied. The findings of the present work indicate that the jetting fountain fluidized bed is more effective in ilmenite oxidation where the oxidation conversion rate increases and the time required for full conversion reduces. Applying jetting fountain configuration enhances gas solids contact and improves the interphases mass exchange between bubbles and emulsion. The oxidation conversion rate was found to improve with bed temperature and fluidization velocity. On the other side, studying the influences of jet air ratio and jet orifice height demonstrate that there is an intermediate value at which the oxidation process records an optimal. The aim of the thesis: The aim of the present work is to apply a novel configuration of fluidized bed, namely, jetting fountain fluidized bed (JFFB) in oxidation process of chemical looping combustion. JFFB is characterized by excellent gas-solids contact due to creating a jet in the upper part of the bed, establishing a fountain in the freeboard and moderating bubbles size in the main bed. The present work presents a comparison study between the JFFB and the conventional fluidized when applied to the oxidation process of CLC. the influences of operating conditions on the effectiveness of oxidation process have been explored. The bed temperature of 800 oC, 850 oC, and 900 oC has been considered. Fluidization velocity has been tested at three cases 0.15 m/s, 0.20 m/s and 0.25 m/s. In jetting fountain configuration, a part of air is fed through the jet while the remaining part is fed through the distributor. Jet air ratio is varied from 0.2 to 0.6. The orifice height of introducing jet air above the distributor plate is also an important parameter. It is varied from 8 cm to 16 cm. In all tests the static bed height is fixed to 15 cm.