Decolorization of Coking Wastewater by mineral adsorbents

摘要

The decolorization of coking wastewater is an urgent issue for coking wastewater treatment. Using mineral adsorbents to deal with the coking wastewater is an effective way to solve the above problem. In this paper, fluidized bed combustion (FBC) ashes, diatomite and clinoptiolite were used to decolorize the coking wastewater. UV-Vis was used to estimate the decolorization efficiency of the FBC ashes. The materials were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results showed that the sequence rule for the decolorization effect of three mineral adsorbents is FBC ashes > diatomite > clinoptiolite. In addition, the chroma of treated coking wastewater reduced from 320 times to less than 5 times in the comparison of raw wastewater. It is much lower than the chroma of GB8978-1996 1A discharge standard. The excellent decolorization effect of FBC ashes might be due to large contains of CaO and f-CaO.