基于Fe2O3载氧体的生物质化学链气化热力学模拟研究

THERMODYNAMIC INVESTIGATION ON BIOMASS CHEMICAL LOOPING GASIFICATION WITH Fe_2O_3 OXYGEN CARRIER

建立以Fe_2O_3为载氧体的生物质化学链气化模型。基于吉布斯自由能最小化原理,利用HSC Chemistry软件对气化系统进行热力学分析与过程模拟。研究燃料反应器内载氧体/生物质比(O/B,mol/mol)、反应温度、水蒸气/生物质比(S/B,mol/mol)、CO_2/生物质比(C/B,mol/mol)等因素对化学链气化系统性能的影响,并评价气化过程中不同氧源的反应活性;考察空气反应器内氧气/铁比(O_2/Fe,mol/mol)对载氧体恢复晶格氧性能的影响。系统的优化参数为:O/B为0.15、燃料反应器温度为1100℃、S/B为0.40、C/B为0.30、O_2/Fe为1.00。

A model of biomass chemical looping gasification （CLG） with Fe2O3 oxygen carrier was firstly built in the present study. And then, thermodynamic analysis and process simulation of CLG were investigated using HSC chemistry soft ware on the basis of Gibbs free energy minimization principle. The effect of oxygen carrier to biomass ratio （O/B, mol/ mol）, temperature of fuel reactor, steam to biomass ratio （S/B, mol/mol）, and CO2 to biomass （C/B, mol/mol） on CLG of biomass were detailed discussed. And the reactivity of different oxygen sources for biomass gasification was evaluated. Additionally, the effect of O2/Fe molar ratio on the oxidation process of reduced oxygen carrier was also discussed. In this work, the thermodynamic analysis indicated that CLG of biomass presented the best performances when O/B, fuel reactor temperature of 1100 ℃, S/B, C/B, and O2/Fe molar ratio was maintained at 0.15, 1100 ℃, 0.40, 0.30 and 1.00, respectively.