Abstract The use of supplementary cementitious materials (SCMs) to replace part of the clinker in cement is the most successful strategy to reduce CO2 emissions in the global cement industry. However, limited supplies of conventional SCMs make it difficult to take this strategy further unless new types of SCMs become available. The only type of material available in the quantities needed to meet demand is clay containing kaolinite, which can be calcined to produce an effective SCM. Such clays are widely available in countries where most growth in demand for cement is forecast. Calcined clays have previously been used as pozzolans, but calcination makes the economics of substitution marginal in a conventional pozzolanic blend. The major innovation presented here is the possibility to make a coupled substitution of cement with calcined clay and limestone. This allows much higher levels of substitution. Blends where calcined clay is used as a pozzolan, typically have clinker contents around 65–70%. Combination of calcined clay with limestone allows higher levels of substitution down to clinker contents of around 50% with similar mechanical properties and improvement in some aspects of durability. The replacement of clinker with limestone in these blends lowers both the cost and the environmental impact.

中文翻译：

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煅烧粘土石灰石水泥 (LC 3 )

摘要 使用补充胶凝材料（SCMs）替代水泥中的部分熟料是全球水泥行业减少二氧化碳排放最成功的策略。然而，除非新型 SCM 可用，否则传统 SCM 的供应有限，因此很难进一步采取这种策略。满足需求所需数量的唯一可用材料类型是含有高岭石的粘土，可将其煅烧以产生有效的 SCM。这种粘土在预计水泥需求增长最快的国家/地区广泛使用。煅烧粘土以前曾被用作火山灰，但煅烧使传统火山灰混合物中替代的经济性变得微不足道。这里介绍的主要创新是用煅烧粘土和石灰石替代水泥的可能性。这允许更高水平的替代。将煅烧粘土用作火山灰的混合物，熟料含量通常约为 65-70%。煅烧粘土与石灰石的组合允许更高水平的替代，低至约 50% 的熟料含量，具有相似的机械性能和耐久性的某些方面的改进。在这些混合物中用石灰石替代熟料可降低成本和对环境的影响。煅烧粘土与石灰石的组合允许更高水平的替代，低至约 50% 的熟料含量，具有相似的机械性能和耐久性的某些方面的改进。在这些混合物中用石灰石替代熟料可降低成本和对环境的影响。煅烧粘土与石灰石的组合允许更高水平的替代，低至约 50% 的熟料含量，具有相似的机械性能和耐久性的某些方面的改进。在这些混合物中用石灰石替代熟料可降低成本和对环境的影响。