浅析煅烧煤矸石对混凝土性能的影响

Analysis on the Influence of Calcined Coal Gangue on the Property of Concrete

煤矿在采煤和选煤过程中会产生大量的固体废弃物-煤矸石,长期堆放会占用大量土地,严重破坏生态环境。由于煤矸石的主要矿物成分为高岭石,而高岭石在低温下煅烧可以脱羟基生成活性偏高岭土,是一种优异的混凝土掺和料。因此煅烧煤矸石获得活性掺和料便是煤矸石再利用的一种有效途径。本文简单综述一下煅烧煤矸石的活性以及对混凝土力学和耐久性能的影响。通过对相关文献的分析可知,要获得较高活性,煤矸石的煅烧温度通常不能超过900度;煅烧煤矸石在适当掺量下可以提高混凝土的早期和后期抗压强度;煅烧煤矸石也会提高混凝土的抗氯离子渗透性和硫酸盐侵蚀性。

In the process of coal mining and coal preparation, coal mine will produce large amounts of solid waste - coal gangue which occupies a large piece of land and produces severe damage to the ecological environment if piled up for a long time. Because the main mineral composition of coal gangue is kaolinite, while calcining kaolinite at low temperature it can generate active metakaolin due to dehydroxylation, which is an excellent concrete admixture, calcining coal gangue for active admixture is an effective way of recycling coal gangue. This article simply reviews the activity of calcined coal gangue as well as the influence of mechanics and durability of concrete. The analysis of the relevant literature show that the calcined temperature cannot exceed 900 degrees to obtain a highly active calcined coal gangue. Calcined coal gangue under appropriate dosage can improve the early and late compressive strength of concrete. And calcined coal gangue can also improve the resistance to chloride ion permeability of concrete and sulfate attack resistance.