面向碳减排的生物质化学链气化特性研究

Investigation on biomass chemical looping gasification character-istics for carbon reduction

中文关键词: 碳减排  化学链气化  含铁污泥灰  载氧体  气化特性

英文关键词: Carbon reduction  Chemical looping gasification  Petrochemical sludge ash  Oxygen carriers  Gasification performance

中文摘要:

      在“双碳”目标指引下，生物质化学链气化技术因可实现负碳排放而备受关注，进行推广应用有望促进能源领域的碳减排。本文以松木屑为生物质燃料、含铁污泥灰为废弃基载氧体，通过固定床反应器-气相色谱研究了含铁污泥灰制备条件优化和实验操作参数对化学链气化性能及循环稳定性的影响。实验结果表明，含铁污泥灰具有提供晶格氧的能力，可以促进松木屑的热解转化，且在煅烧温度800℃下制备的污泥灰催化性能最佳，获得的合成气热值最高，达到11.63MJ/Nm3。通过对含铁污泥灰进行水洗和酸洗处理，灰分中Fe2O3含量由53.37%分别升高至61.38%和64.46%，提高了晶格氧供给能力。进一步，对水洗和酸洗后的污泥灰进行不同比例、不同温度以及循环实验，发现松木屑的化学链气化反应性能均得到了一定提升，其中水洗污泥灰的最佳气化温度为800℃，合成气热值达到了13.89MJ/Nm3，酸洗污泥灰的最佳气化温度较低为750℃。经过水洗和酸洗处理的污泥灰在化学链气化过程中均展现出较为稳定的反应性能，且通过实验证明所含Fe2O3的还原遵循Fe2O3→Fe3O4→FeO/Fe的逐级反应过程。本研究通过探究含铁污泥灰制备条件和实验操作参数对松木屑化学链气化过程的影响规律，以期实现固体废弃物资源化利用、生物质高效转化和以废治废的目标，为其在能源领域推广应用和助力碳减排提供有益参考。

英文摘要:

      Under the guidance of the "dual carbon" target, the biomass chemical looping gasification technology has attracted many attentions for its ability to achieve negative carbon emissions, and its promotion and appli-cation are expected to promote carbon reduction in the energy sector. This research applied pine sawdust as biomass fuel and iron-containing sludge ash as waste-based oxygen carrier, and the effects of different preparation conditions and experimental operating parameters on the chemical looping gasification per-formances and cycling stability of iron-containing sludge ash were studied through a fixed bed reactor coupled with a gas chromatography (GC). The experimental results showed that, the iron-containing sludge ash had the ability to provide lattice oxygen, which could promote the pyrolysis conversion of pine saw-dust. The sludge ash prepared at a calcination temperature of 800℃ had the best catalytic performance, and the highest calorific value of syngas was obtained, reaching 11.63MJ/Nm3. By water washing and acid washing on the iron-containing sludge, the Fe2O3 content in the ash increased from 53.37% to 61.38% and 64.46%, respectively, improving the supply capacity of lattice oxygen. Furthermore, different ratios, tem-peratures, and cycling experiments were conducted on the sludge ash after water washing and acid washing, and it was found that the chemical looping gasification reaction performances of pine sawdust were im-proved to some extent. The optimal gasification temperature for water washing sludge ash was 800℃, and the calorific value of syngas reached 13.89MJ/Nm3. The optimal gasification temperature for acid washing sludge ash was lower at 750℃. The sludge ash treated with water washing and acid washing exhibited rela-tively stable reaction performance during the chemical looping gasification process, and it had been exper-imentally proven that the reduction of Fe2O3 follows a stepwise reaction process of Fe2O3 → Fe3O4 → FeO/Fe. This study aimed to explore the influence of preparation conditions and experimental operating parameters of iron-containing sludge on the chemical looping gasification process of pine sawdust, in order to achieve the goals of solid waste resource utilization, efficient biomass conversion, and waste treatment, and provide useful references for its promotion and application in the energy field and assistance in carbon reduction.