High-Temperature Sorption of Hydrogen Sulfide and Carbonyl Sulfide by Fe2O3/SiO2

• Main Authors: Jing-ying Huang, 黃瀞瑩
• Other Authors: Hsin Chu
• Format: Others
• Language: zh-TW
• Published: 2007
• Online Access: http://ndltd.ncl.edu.tw/handle/29633470005198307813

碩士 === 國立成功大學 === 環境工程學系碩博士班 === 95 === With the increase of the population and demands for better life in the world, the energy, such as petroleum and natural gas, are exhausted and their prices are booming. For the need of diversified clean energy, the use of coal-burning power will increase obviously in the future. Integrated Gasification Combined Cycle (IGCC) is one of the ideal technologies, which mainly uses coal to generate power. It can reduce the emissions and improve the efficiency of coal-burning. This technology will become the main stream of power supply in the future. Nowadays, all commercial IGCC power plants use wet desulfurization processes to remove H2S from hot syngas, but they have to use large amount of water and, thus, decrease the thermal efficiency of the system. In order to solve this problem, the high temperature desulfurization by dry techniques is a trend for related fields. Desulfurization of hot coal gas using homemade Fe2O3/SiO2 sorbent in a fixed bed reactor was conducted in this study. The discussion of results can be divided into five major parts. 1. The Fe2O3 sorbent supported on SiO2 exhibits higher sorbent utilization than the Fe2O3 sorbents supported on γ-Al2O3 and ZrO2. 2. The operating temperatures around 500℃ is optimal for the Fe2O3/SiO2 sorbent. 3. The effects of operating parameters, such as space velocity and inlet concentrations of CO, H2, H2S and COS, on the removal of H2S and COS were performed. Results indicate that the breakthrough time increases with the CO concentration and decreases with the H2 concentration. Thiscan be explained through the water-shift reaction. Space velocity between 3,000~18,000 mL·hr-1·g-1, H2S concentration and COS concentration, however, maintain nearly constant sorbent utilization in the operation conditions. 4. Under reduction conditions, Fe2O3 sorbent will be reduced to low-activity iron oxides. Under oxidation conditions, the sulfurated ferrite sorbent will be oxidized to FeSO4 first. It will be further oxidized to the ferrite sorbent. 5. In the operating range of this study, it can be found that the activation energy, Ea, is 103 kJ/mol and the frequency factor, A, is 1.4 × 1017 for type I model. The activation energy, Ea, is 65.5 kJ/mol and the frequency factor, A, is 4.3 × 1014 for type II model.