Abstract Chemical-looping combustion (CLC) technology can play a significant role in decreasing costs for CO2 capturing in the future. The technology relies on the use of an oxygen carrier (OC) material, which becomes a solid waste material after it is deactivated. The aim of this study was to verify the possibility to produce high-strength ceramic proppants from a spent Cu-based OC, consisting mainly of α-Al2O3 and a minor content of CuAl2O4. Experiments were carried out with both pure α-Al2O3 and a spent Cu-based OC delivered from a pilot CLC plant. Milling, granulation and sintering were the main process steps developed in the study. The results clearly demonstrated the technical feasibility to use a Cu-based spent OC as a raw material for producing high-strength ceramic proppants. After milling for 1 min, granulation and sintering at 1400 °C, ceramic particles with a compressive strength > 100 MPa and a sphericity of 0.9 were obtained. Further increasing the sintering temperature to 1600 °C enabled to reach compressive strengths > 150 MPa. At this sintering temperature the CuAl2O4 melted and separated from the solid ceramic spheres.

中文翻译：

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废铜基氧载体回收成高强度陶瓷支撑剂

摘要 化学循环燃烧 (CLC) 技术可以在未来降低 CO2 捕集成本方面发挥重要作用。该技术依赖于氧载体 (OC) 材料的使用，该材料在失活后成为固体废物。本研究的目的是验证从主要由 α-Al2O3 和少量 CuAl2O4 组成的废铜基 OC 生产高强度陶瓷支撑剂的可能性。实验是用纯 α-Al2O3 和从 CLC 试验工厂提供的废铜基 OC 进行的。研磨、造粒和烧结是研究中开发的主要工艺步骤。结果清楚地证明了使用Cu基废OC作为生产高强度陶瓷支撑剂的原料的技术可行性。研磨1分钟后，在1400℃下造粒和烧结，获得了抗压强度 > 100 MPa 和球形度为 0.9 的陶瓷颗粒。进一步将烧结温度提高到 1600 °C，可以达到 > 150 MPa 的抗压强度。在该烧结温度下，CuAl2O4 熔化并与固体陶瓷球分离。