Trace elements emission in iron ore sintering: A review

•The choice of raw materials is an effective way to control trace elements emission.•Iron ore is the most relevant raw material for input trace elements in sintering.•Most trace elements are retained in air pollution control devices as particulates.•Volatile and semi-volatile elements are difficult to remove by conventional methods. Iron ore sintering is the main process of fines agglomeration for ironmaking with relevant particulate matter and trace element emissions of integrated steel plants. Due to the high environmental and human health impacts caused by trace elements, legislations are becoming more stringent for regulating emissions of the trace elements. This review consolidates several studies in the sector, focusing on the sources, behavior, and technologies employed to control emissions of trace elements during iron ore sintering. The emission of trace elements is strongly dependent on the characteristics of raw materials, operating parameters and technologies used for their abatement. Iron ore is the main responsible material for emissions of trace elements during sintering as it undergoes a series of physicochemical transformations throughout the process. In general, trace elements may remain in the solid-state, volatilize during combustion and recondense in the cleaning system, or remaining in the gaseous state during the flue gas treatment. Although most trace elements are retained in air pollution control devices in the form of particulates, volatile and semi-volatile elements (As, Se, Hg, Cd, etc) can remain as gases or concentrate in the finer particulates. Modern technologies have demonstrated high efficiency in removing these elements from the flue gases. [Display omitted]