蒸汽重整生物质复合氧载体气化制备合成气的协同机制研究

With aiming to cope with technical problems of small ratio of H2/CO, small concentration of effective components, and low carbon conversion in the course of synthesis gas generation by biomass gasification, this program will provide a new idea of synthesis gas generation by steam reforming and oxygen-carrier gasification of biomass. After generation and selection of a high-performance combined oxygen carrier, a method of combining experimental study with theoretic analysis will be used to provide research on synergistic effect of combined oxygen-carrier gasification and steam reforming, establish a model of synthesis gas generation by steam reforming and oxygen-carrier gasification of biomass, identify optimal combinations in system operation, clarify the effect of interaction of oxygen-carrier gasification and steam reforming on gaseous product release, and reveal the synergistic effect and directional control in synthesis gas generation by steam reforming and oxygen-carrier gasification. Characterization and performance testing are to be conducted for the combined oxygen carrier to evaluate the activity promotion of iron-based oxygen carrier by inert carrier, specify characteristics and transmission means of lattice oxygen in the combined oxygen carrier, clarify the selective oxidation and carbon distribution of the combined oxygen carrier, and reveal the activation and evolution of gaseous product on the combined oxygen carrier. This research will provide references for synthesis-gas quality improvement and dimethyl ether generation.

为了解决生物质气化制备合成气过程中存在的H2/CO比例小、有效组分浓度低、C转化率不高等技术难题，本项目以氧载体气化原理为依据，提出蒸汽重整生物质复合氧载体气化制备合成气的新思路。在制备和筛选出高性能的复合氧载体基础上，采用实验研究和理论分析相结合的办法，开展生物质复合氧载体气化与水蒸气重整反应的协同效应研究，构建蒸汽重整生物质复合氧载体气化系统模型，确定系统运行的优化组合条件，阐明生物质复合氧载体气化与水蒸气重整反应的交互作用对气相产物释放行为的影响规律，揭示蒸汽重整生物质复合氧载体气化制备合成气过程的协同作用和定向控制机制。通过复合氧载体结构表征和性能测试，评价惰性载体对铁基氧载体的活性促进作用，提出复合氧载体晶格氧的释放特点及传输途径，阐明复合氧载体的选择性氧化及积碳机理，揭示气相产物在复合氧载体表面上的活化方式和演变历程。项目研究将为合成气品质提升和制备二甲醚燃料提供参考依据。

合成气（H2+CO）是一种重要的化工原料。随着化石能源的日益枯竭和不断严重的环境问题，发展以可再生资源为原料的合成气生产工艺对缓解世界能源短缺和环境污染具有重要的意义。为了解决生物质气化制备合成气过程中存在的H2/CO比例小、有效组分浓度低、C转化率不高等技术难题，本项目以氧载体气化原理为依据，提出蒸汽重整生物质复合氧载体气化制备合成气的新方法。具体进行了复合氧载体制备与筛选、生物质化学链气化蒸汽重整特性、工艺参数优化、协同效应、耦合机理等一系列研究。阐明了生物质复合氧载体气化与水蒸气重整反应的交互作用对气相产物释放行为的影响规律，揭示了蒸汽重整生物质复合氧载体气化制备合成气过程的协同作用和定向控制机制。研究结果表明Al2O3为载体，60%负载的铁基复合氧载体较适合用于生物质氧载体气化制备合成气。最优系统运行条件为反应时间为20min，反应温度为850℃，生物质，氧载体和水蒸气三者之间的最优配比为1:1:2.8。在最优工况下，合成气中H2/CO的值达到1.93，H2与CO的总含量达到79.73%，碳转化率85.89%。水蒸气的加入明显改善了合成气的品质，而且对复合氧载体的抗积碳能力有所提高。项目研究将为合成气品质提升和制备二甲醚燃料提供参考依据。