Pyrolysis reactions and reactions of pyrolysis products in Sorption Enhanced Biomass Gasification in a Calcium Looping System

与其他气化工艺相比，吸附强化气化（SEG）允许直接生产氢气或具有定制成分的合成气。由于可以就地捕获CO2， SEG工艺省去了额外的移位反应器将CO转化为H2的要求。当使用生物燃料时，SEG过程可以产生可再生氢或其他可再生燃料或化学品。这说明了该工艺在减少当前对化石石油和天然气依赖方面的潜力。近年来，SEG工艺从实验室迅速发展到中试规模。尽管该工艺的适用性已被成功证明，但涉及生物质转化，特别是生物质热解和随后的重整反应的一些基本问题仍未解决，这些问题阻碍了SEG工艺的进一步优化，从而阻碍了SEG工艺的商业应用。PyroSEG项目旨在通过在宏观热重分析仪和实验室规模鼓泡流化床系统上对SEG特定条件下生物质一次热解和热解产物后续二次反应的基础研究，全面解决这些问题。此外，还研究了吸附剂和炭对热解产物焦油裂解和重整的影响。SEG过程的其他反应，如炭气化和吸附剂碳酸化，在过去已经描述得相对较好，因此在PyroSEG中不会详细研究。除了热解反应外，PyroSEG还将实验分析含有石灰石吸附剂和生物质焦的混合物的流化床的流体动力学，重点研究焦和床层偏析等影响。基于扩展和新的经验数据，将开发先进的过程模型，允许更准确和详细地模拟过程及其在效率和合成气质量方面的改进。这种模拟的结果将与其他研究项目范围内在双流化床（DFB）系统中进行的实验SEG结果进行比较。PyroSEG中开发的模型将是将研究结果外推到更大规模应用的强大工具，并根据某些条件（即可变类型的生物质或合成气利用路线）定制工艺设计。所进行实验的样品和其他结果将由项目合作伙伴共同分析和评估。在整个项目中，合作伙伴将密切合作，并将分享和讨论实验和结果。这将包括专门的相互研究访问和其他定期的个人和电话会议。该项目的目标是在至少四篇（其中两篇是已加入的）同行评议论文中传播其结果。

In contrast to other gasification processes, sorption enhanced gasification (SEG) allows for the direct production of hydrogen or of a syngas with a tailored composition. Due to in-situ capture of CO2, the SEG process omits the requirement of an additional shift reactor to convert CO to H2. When operated with biogenic fuels, the SEG process can produce renewable hydrogen or other renewable fuels or chemicals. This illustrates the process’ potential when aiming to reduce the current dependency on fossil oil and gas. The SEG process has been rapidly developed from lab to pilot scale in recent years. Even though, the process’ applicability has been demonstrated successfully, a number of fundamental questions involving biomass conversion and especially biomass pyrolysis and subsequent reforming reactions remain open and hinder the further optimization and in consequence the commercial application of the SEG process. The PyroSEG project aims to resolve those issues following a comprehensive approach with fundamental investigations on primary biomass pyrolysis and subsequent secondary reactions of the pyrolysis products under SEG specific conditions at a Macro-TGA and a laboratory scale bubbling fluidized bed system. Moreover, the influence of the sorbent and char on tar-cracking and reforming of pyrolysis products will be studied. Other reactions of the SEG process such as char gasification and sorbent carbonation have been described relatively well in the past and hence will not be investigated in detail in PyroSEG. In addition to pyrolysis reactions, in PyroSEG the hydrodynamics of a fluidized bed containing a mixture the limestone sorbent and biomass char will be experimentally analyzed, focusing on effects such as char and bed segregation. Based on extended and new empirical data, advanced process models will be developed, allowing a more accurate and detailed simulation of the process and its improvement in respect to efficiency and syngas quality. Results of such simulations will be compared to experimental SEG results from experiments conducted in a dual fluidized bed (DFB) system within the scope of other research projects. The models developed in PyroSEG will be powerful tools to extrapolate research results to a larger scale application and to tailor the process design to certain conditions (i.e. variable types of biomasses or syngas utilization routes). Samples and other results from the conducted experiments will be jointly analyzed and evaluated by both project partners. Throughout the project, the partners will work in a close collaboration and will share and discuss experiments and results. This will involve dedicated mutual research visits and other regular personal and telephone meetings. The project aims to disseminate its results in at least four (two of those joined) peer reviewed papers.