Because the CO₂ capture is inherent in chemical looping combustion (CLC), thus ideally avoiding costly gas separation, this process has potential for uniquely low costs of CO₂ capture. The review reports on operational experiences with different oxygen carriers in CLC pilot operation. Further, the application to solid fuels is discussed in terms of technology challenges, routes for upscaling to commercial size, downstream gas treatment, options for achieving adequate circulation, and the use of biofuels in CLC to reach negative emissions. It is concluded that the necessary elements for a scale-up are at hand. Oxygen carrier materials of low cost have been tested in extended operation and found to have reasonable performance with respect to reactivity and lifetime. Designs for large-scale units have been performed, indicating that the process is technically realistic and should have a low cost of CO₂ capture. A scale-up strategy to minimize risk and costs has been suggested.

中文翻译：

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化学循环燃烧：现状与发展挑战

由于CO ₂捕集是化学循环燃烧（CLC）固有的，因此理想地避免了昂贵的气体分离，因此该工艺具有独特的CO ₂低成本潜力捕获。该评论报告了CLC试运行中使用不同氧气载体的操作经验。此外，还将讨论技术挑战，扩大规模以达到商业规模的途径，下游气体处理，实现充分循环的选择以及在CLC中使用生物燃料以达到负排放的方式，讨论在固体燃料中的应用。结论是，扩大规模的必要要素已经到手。低成本的氧气载体材料已经在扩展的操作中进行了测试，发现在反应性和寿命方面具有合理的性能。已经进行了针对大型装置的设计，这表明该工艺在技术上是现实的，并且应该具有较低的CO ₂捕集成本。已经提出了扩大规模的策略，以最大程度地降低风险和成本。