الفهرس | Only 14 pages are availabe for public view |
Abstract Recently, the greenhouse effect has been the focus of attention of many scientists; this is due to the increase in earth’s surface temperature in the last century. Carbon dioxide is one of the main gases that cause global warming, so CO2 capture techniques have been the focus of attention these days. The Chemical-looping combustion (CLC) is one of these techniques that do not waste energy during the process of CO 2 separation and capture. It is unmixed combustion technique, because fuel and air do not have a direct reaction. The oxygen is separated from the air by using a metal powder, which is called oxygen-carrier and the process of combustion is carried out by oxygen only. The product flue gases ”CO 2 and H 2 O” from the combustion of fuel leave the system as a stream. The amount of H2 O can be easily removed by condensation. Therefore, pure CO2 can be obtained without expensive energy for separation process. from previous work, it is clear that chemical-looping combustion technology can be applied as an efficient method for producing high purity of CO2 . The aim of this study is to assess combustion of gaseous and solid fuel in the chemical-looping combustion technology. This study includes experimental and numerical approaches for using lignite coal and liquefied petroleum gas (LPG) as solid and gaseous fuel respectively. The experimental setup was designed and fabricated at the lab of combustion in faculty of Engineering, Suez Canal University. The chemical-looping combustor system involves two interconnected fluidized beds. Nickel powder with 150-µm diameter was used as an oxygen carrier. The gaseous fuel is LPG that consists of 60% propane (C 3H8 ) and 40% butane IV (C 4H10). In addition, computational fluid dynamic (CFD) model was built according to the experimental setup. The experimental and computational simulation results were validated according to different statistical methods such as the coefficient of determination (R 2 ). The assessment of combustion in this work is concentrated on measuring the products CO and CO 2 then make a comparison of the results in the case of conventional combustion and after the applying CLC technology. The results in general showed that, with using the CLC technology the combustion behavior was improved in case of using LPG as gaseous fuel the color of the flame changed to blue and that is indicates to approaching complete combustion flame. The CO was decreased by 49.1% and CO2 was increased by 66.5% compared with traditional combustion. Moreover, in case of using lignite coal as solid fuel, CO was decreased by 53.7% and CO 2 was increased by 71.9% compared with traditional combustion. In addition, the results showed that there is a good agreement between the experimental and numerical results. . |