Studies on Characteristics of Semi-Dry FGD Ash from Iron Industry

Some samples of ash were taken from a Semi-dry FGD dealing with sinter gas which was released from iron industry. Scanning electron microscope (SEM), X-ray diffraction (XRD) and Fourier Transform Infrared Spectrometer (FTIR) were employed to identify the samples in order to investigate their physical and chemical characteristics. The result shows that: this kinds of semi-dry FGD ash is stable, and its characteristics have no significant change in the dry environment at room temperature. The contents of CaSO₃ and SO₃ in the semi-dry FGD ash from iron industry are higher than those from power plant gas. The semi-dry FGD ash has smooth surface, loose structure and contain many small holes. It is consist of CaSO₃, CaSO₄, CaCO₃, corundum and mullite, et al. The diameter of the ash is distribute from 3.42 mu m to 13.77 mu m, the mean particle diameter is about 4.18 mu m and specific surface area is about 7.94 m²/g.