摘要
为了研究两级气化技术,针对鼓泡流化床建立生物质气化的三维模型,气相采用k-ε湍流模型,固相采用颗粒动力学理论,并加入化学反应子模型,研究了低当量比下生物质产气组分随当量比、富氧浓度和流化速度的变化规律,分析了产气组分中的焦油含量。结果表明:当量比增大时,CO和H_2的浓度先增大后减小,CO_2的浓度逐渐减小;随着富氧浓度的升高,CO和CO_2的浓度迅速增大,H_2的浓度略有下降;随着流化速度的增大,CO的浓度增大,CO_2的浓度减小,H_2的浓度略有增加;出口产气组分中的焦油含量相对较高,需要在下一步工艺中进行深度裂解。
To study the two-stage gasification technology, a three-dimensional numerical model was established to simulate the biomass gasification process in bubbling bed using k-ε turbulent model for the gas phase and kinetic theory of granular flow for the solid phase, and a chemical reaction sub-model was also used to study the change law of biomass gas composition with the equivalence ratio, oxygen concentration and flow velocity at low equivalence ratios, while the tar content in gas components was analyzed. Results show that with the rise of equivalence ratio, the concentration of CO and H2 first increases and then decreases, while that of CO2 decreases gradually. Whereas with the rise of oxygen concentration, the concentration of CO and CO2 increases rapidly, while the concentration of H2 decreases slightly. With the rise of flow velocity, the concentration of CO increases, while the concentration of CO2 decreases, with a slight increase of H2 concentration simultaneously. The tar content is relatively high in the outlet gases, so deep cracking is considered to be necessary in the next process.
作者
陆杰
金保昇
Lu Jie Jin Baosheng(Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, Southeast University, Nanjing 210096, China)
出处
《发电设备》
2017年第2期71-75,共5页
Power Equipment
关键词
生物质气化
三维模型
低当量比
富氧浓度
焦油
biomass gasification
three-dimensional model
low equivalence ratio
oxygen concentration
tar
