| Summary: | 碩士 === 國立成功大學 === 環境工程學系碩博士班 === 98 === With the increasing population and the burgeoning industrial development, the energy demand for petroleum and natural gas has been growing up rapidly. Integrated Gasification Combined Cycle (IGCC), one of the most ideal technologies, utilizes coal to generate electricity, which is capable of not only reducing the emissions but also improving the efficiency of coal-burning. Thus this technology of coal-burning power is considered one of society’s greatest needs in the future. Nowadays, almost all commercial IGCC power plants use wet desulfurization and dechlorination processes to remove H2S/HCl and other deleterious gases from hot syngas by the use of large amount of water, resulting in the decreasing thermal efficiency of the system. Consequently, the development of dry desulfurization at high temperature becomes vitally important in this field.
Desulfurization and dechlorination of syngas using homemade Fe2O3/SiO2 sorbent in a fixed bed reactor was conducted in this study. Results of this study are described as follows:
1.Experimental results revealed that 10% Fe2O3/SiO2 had the best performance on simultaneous removal of H2S and HCl.
2.500°C was considered the optimal operating temperature for the 10% Fe2O3/SiO2 sorbent to simultaneously remove H2S and HCl.
3.It was found that the sorbent utilization increased with rising H2S concentration and decreasing HCl concentration, which was assumed to be related to the higher reactivity between Fe2O3 and H2S.
4.The inlet CO concentration showed no evident influence on the sorbent utilization; while higher H2 concentration was found to increase the sorbent utilization. Additionally, Space velocity between 2,000~9,000 mL hr-1 g-1 also had no significant effect on the utilization.
5.Through five-time regeneration tests an evident reactivity degradation of the sorbent was found after the first test, and as the experiments proceeded, the degradation phenomenon gradually reduced. Moreover, regenerating the sorbent with air could shorten the regeneration time within 30 minute.
6.Under the reducing environment Fe2O3 contained in the sorbents were reduced low-activity iron oxides; while under oxidizing environment the sulfurated ferrite sorbents were oxidized to FeSO4 first and then were further oxidized to the original ferrite sorbent.
7.To obtain more information on gas phase changes during the sorption experiment, outlet gases were monitored and recorded through on-line FTIR at various periods. By-products like CO2, CS2 and CH4 were found to have vital influence on the reaction, and CO and H2 were also discovered to play an important role in this system.
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