循环流化床气化原位吸储氢吸附强化水汽变换制氢机理研究

Hydrogen production from a large number of solids feedstock consists of gasification, water gas shift (WGS), pressure swing adsorption (PSA) and waste heat recovery. Carbon contents in the slag and fly ash from fluidized-bed gasification are usually higher, and tars can be produced. Hydrogen purity, selectivity and conversion are not high due to WGS thermodynamic equilibrium limited. New technology on hydrogen production in this project is carried out by in-situ H2 sorption-enhanced WGS reaction combined circulating fluidize-bed gasification. Gradually widening cone type furnace with different staged fluidization is designed and makes the particles with bed height increase showed different distribution characteristics. The gas-solid flow can be distributed uniformly and the residence time of small particles in the furnace is increased. Tars can be eliminated by high temperature during combustion and gasification process with CaO injection. CO WGS reaction equilibrium is broken with the dynamic coupling by in-situ H2 sorption to increase the selectivity and conversion. WGS catalyst and materials of H2 sorption always in near fresh states are moved by slow moving bed for continuous reaction and regeneration to pure hydrogen production. Theory and key factors on multiphase flow, gasification and combustion in circulating fluidized bed furnace will be studied. The characteristics of in-situ H2 sorption in WGS reaction, kinetics and mechanisms of reaction equilibrium movement will be explained. Several kinds of hydrogen storage materials in WGS environment will be developed and the strategy in their structures and performances improvements is clarified. The mechanisms of hydrogen production and in-situ sorption/storage as well as the methods of system control will be explored.

大量固体原料热转化制氢包括：原料气化、水汽变换、变压吸附及余热回收等，通常流化床气化排渣与飞灰碳含量较高，水汽变换受热力学平衡限制，产氢纯度、选择性和转化率均不高。本项目提出：循环流化床气化原位吸储氢吸附强化水汽变换制氢新技术，以变径炉膛逐级流态化理论，使不同颗粒随床层高度增加呈现不同分布特征，提高气固接触均匀性和细轻颗粒炉内停留时间，高温气化喷钙增效抑制污染产生；以动力学耦合，原位吸储氢，打破水汽变换反应平衡限制，提高选择性和转化率，慢速移动床实现催化剂和吸氢材料连续移动、反应和再生，使其始终处于近新鲜状态，吸附强化连续一步制纯氢，节省产品分离。项目揭示变径循环流化床多相混合流动、气化原理及影响因素，重点研究水汽变换原位吸储氢特性、动力学及引起制氢关键反应平衡移动的作用机制，发展几种在水汽变换特定使用环境的吸氢材料并澄清其结构性能调变策略，弄清新工艺制氢原位吸储氢机理与调控方法。

大量生物质固体原料热转化制氢包括：原料热解气化、水汽变换、变压吸附及余热回收等，通常水汽变换受热力学平衡限制，产氢纯度、选择性和转化率均不高。本项目提出：生物质热解气化原位吸储氢吸附强化水汽变换制氢新技术，以动力学耦合，通过热解气化原位吸储氢，打破水汽变换反应平衡限制，提高选择性和转化率，慢速移动床实现催化剂和吸氢材料连续移动、反应和再生，使其始终处于近新鲜状态，吸附强化连续一步制纯氢，节省产品分离。项目揭示生物质热解气化原理，影响因素及动力学，重点研究水汽变换原位吸储氢特性、动力学及引起制氢关键反应平衡移动的作用机制，发展几种在水汽变换特定使用环境的吸氢材料并澄清其 结构性能调变策略，弄清新工艺制氢原位吸储氢机理与调控方法；Aspen Plus研究了H2 吸附对 CO 水汽变换的强化作用，研究过程能量转换和参数优化。本项目研究取得了较好的研究成果，共发表国际SCI收录论文14篇（第一标注），其中影响因子IF 10以上4篇，授权发明专利4项，申请发明专利2项，培养博士生2名，硕士生8名，2名研究生获上海市优秀毕业生，2名研究生获国家奖学金，本项目部分研究内容2020年获上海市自然科学二等奖1项。项目负责人获2021年上海市优秀学术带头人、2021年上海市育才奖。