摘要
A three-dimensional numerical model verified by previous experimental data is developed to simulate the fluidized bed gasification of refuse derived fuel （RDF）. The CaO dechlorination model obtained by the thermal gravity analysis （TGA） is coupled to investigate the process of CaO dechlorination. An Eulerian-Eulerian method is adopted to simulate the gas-solid flow and self-developed chemical reaction modules are used to simulate chemical reactions. Flow patterns, gasification results and dechlorination efficiency are obtained by numerical simulation. Meanwhile, simulations are performed to evaluate the effects of Ca/Cl molar ratio and temperature on dechlorination efficiency. The simulation results show that the presence of bubbles in the gasifier lowers the CaO dechlorination efficiency. Increasing the Ca/Cl molar ratio can enhance the dechlorination efficiency. However, with the temperature increasing, the dechlorination efficiency increases initially and then decreases. The optimal Ca/Cl molar ratio is in the range of 3. 0 to 3. 5 and the optimal temperature is 923K.
首先建立了与试验台一致的鼓泡流化床垃圾衍生燃料气化的三维数值模型,并在此基础上导入热重试验得到的CaO脱氯模型,研究了CaO脱氯规律. 其中,流场计算采用欧拉两相流模型,化学反应采用UDF导入,模拟得到了反应器内气固流动特性、气化结果及脱氯效率. 此外,通过模拟不同工况,得出了不同Ca/ Cl摩尔比和反应温度对脱氯效率的影响规律. 模拟结果表明,在脱氯过程中, CaO脱氯效率会受到鼓泡床中气泡的影响;CaO脱氯效率随着Ca /Cl摩尔比的增加而增加,但随反应温度的升高呈先上升后下降的趋势, 最佳 Ca/Cl摩尔比在 3.0 - 3.5之间,最佳脱氯温度为923 K.
基金
The National Natural Science Foundation of China(No.51476032)
