Construction Engineering Area, School of Engineering Science of Belmez, Universidad de Córdoba, Avda. de la Universidad s/n, 14240, Belmez, Córdoba, Spain.
Department of Inorganic Chemistry and Chemical Engineering, School of Engineering Science of Belmez, Universidad de Córdoba, Avda. de la Universidad s/n, 14240, Belmez, Córdoba, Spain.
Environ Sci Pollut Res Int. 2020 Jan;27(1):89-100. doi: 10.1007/s11356-019-04948-y. Epub 2019 Apr 10.
Among the actions proposed by the European Union for the implementation of Circular Economy is the use of waste as a secondary raw material (SRM). During the fusion of the scrap, a steel dust is generated, named electric arc furnace dust (EAFD). The EAFD is composed mainly of potentially leachable heavy metals and is classified as a "hazardous" waste. Worldwide, approximately 70% of EAFD is deposited in landfills, with a previous treatment through cement-based materials to prevent the metals' mobility. However, this action is not in accordance with the Circular Economy concept. The present investigation analyses the use of EAFD as SRM in conventional mortar production for its use as a construction material. Different substitution percentages (25, 50 and 100%) were used replacing the siliceous filler by EAFD. A preceding characterisation of the waste by X-ray fluorescence, X-ray diffraction, specific surface area, bulk density, electron microscopy and particle size distribution was performed. The investigation analysed the behaviour of conventional mortars by tests of workability, compressive strength, mineralogy, water absorption by capillarity, and leaching behaviour in granular and monolithic states. The results obtained indicate a slight improvement in mechanical behaviour with the incorporation of EAFD, the reason why its use as SRM in conventional mortars would benefit the construction industry and would encourage the Circular Economy. From an environmental point of view, the mechanisms of Pb fixation should be improved in a granular state.
在欧盟为实施循环经济而提出的各项行动中，使用废物作为二次原材料（SRM）是其中之一。在废钢的融合过程中，会产生一种名为电弧炉粉尘（EAFD）的钢尘。EAFD 主要由潜在可浸出的重金属组成，被归类为“危险”废物。在全球范围内，大约 70%的 EAFD 被储存在垃圾填埋场中，之前通过水泥基材料进行处理，以防止金属的迁移。然而，这种做法不符合循环经济的概念。本研究分析了将 EAFD 用作 SRM 来生产传统砂浆，以将其用作建筑材料。通过用 EAFD 替代硅质填料，分别使用了 25%、50%和 100%的不同替代率。通过 X 射线荧光、X 射线衍射、比表面积、体密度、电子显微镜和粒度分布对废物进行了预先的特性描述。通过工作性、抗压强度、矿物学、毛细吸水、颗粒状和整体状态下的浸出行为等测试，研究分析了传统砂浆的性能。研究结果表明，随着 EAFD 的掺入，机械性能略有提高，因此将其作为 SRM 用于传统砂浆将有益于建筑行业并鼓励循环经济。从环境角度来看，在颗粒状态下，应改善 Pb 固定的机制。
