基于Aspen Plus的生物质化学链气化耦合CO2裂解模拟研究

生物质化学链气化耦合CO₂裂解技术能够在产生高品质合成气的同时将CO₂转化为CO，是可以同步实现CO₂增量降低和存量减少的有效手段之一。使用Aspen Plus软件，建立了生物质化学链气化耦合CO₂裂解过程的模型，研究了温度、压力和生物质与氧载体质量比(m(Biomass)/m(Oxygen carrier)，简称m_B/m_O)对反应产出合成气组分、气化特性参数和系统热负荷的影响。结果表明：随着温度的升高，反应产出的合成气中CO、H₂含量呈现上升趋势，CO₂、CH₄含量下降，产气热值增大，且在高于800 ℃时趋于稳定，反应温度在1000 ℃以下时，系统产热可以满足反应需要；当反应压力由0.1 MPa提高至0.5 MPa时，H₂、CO含量下降，CO₂含量提高，合成气热值下降，系统整体放热量增大；当m_B/m_O增大时，生物质进料量逐渐增多，氧载体还原产物中Fe含量增大，FeO含量降低，合成气热值上升；当m_B/m_O在0.3~1.3区间内时，系统产热可以满足系统反应所需。耦合CO₂裂解反应器后碳转化率有较大提升，并且在m_B/m_O为0.7时提升最为显著。

A Study on the Simulation of Biomass Chemical Looping Gasification Coupled with CO2 Pyrolysis Based on Aspen Plus

The technology of biomass chemical looping gasification coupled with CO₂ pyrolysis can be used for converting CO₂ into CO while producing high-quality syngas, which is one of the effective means to synchronously reduce the increment and stock of CO₂. Using Aspen Plus software, this paper establishes a model for the biomass chemical looping gasification coupled with CO₂ pyrolysis, and study the effects of temperature, pressure and mass ratio of biomass to oxygen carrier (m(Biomass)/m(Oxygen carrier), known as m_B/m_O for short) on the components of the syngas produced during reaction, gasification characteristic parameters and system heat load. The results show that with the rise of temperature, the content of CO and H_{2 i}n syngas shows an upward trend, while the content of CO₂ and CH₄ shows a downward trend. The calorific value of syngas increases and tends to be stable above 800 ℃. When the reaction temperature is below 1000 ℃, the heat production of the system can meet the needs of reaction. When the reaction pressure increases from 0.1 MPa to 0.5 MPa, the content of H₂ and CO decreases, the content of CO₂ increases, the calorific value of syngas decreases, and the heat release of the whole system increases. When m_B/m_O increases, the biomass feed increases gradually, the content of Fe in oxygen carrier reduction product increases, the content of FeO decreases, and the heat value of syngas increases. When m_B/m_O falls within the range of 0.3—1.3, the heat production in the system can meet the needs of system reaction. After being coupled with CO₂ pyrolysis reactor, the carbon conversion can be improved greatly, mostly significant when m_B/m_O is 0.7.