Weng Qiyu, Gong Yingli, Tian Xiongwei, Zhuo Yuqun, Wang Shujuan, Hu Pengbo, Lyu Tao
Department of Energy and Power Engineering, Tsinghua University, Beijing 100084, China; Key Laboratory for Thermal Science and Power Engineering of the Ministry of Education, Department of Energy and Power Engineering, Tsinghua University, Beijing 100084, China.
Department of Energy and Power Engineering, Tsinghua University, Beijing 100084, China; Key Laboratory for Thermal Science and Power Engineering of the Ministry of Education, Department of Energy and Power Engineering, Tsinghua University, Beijing 100084, China; Beijing Engineering Research Center for Ecological Restoration and Carbon Fixation of Saline-Alkaline and Desert Land, Beijing 100084, China.
J Hazard Mater. 2021 Aug 15;416:125823. doi: 10.1016/j.jhazmat.2021.125823. Epub 2021 Apr 20.
Selenium is one of the hazardous trace elements emitted from coal-fired power plants. The distribution of selenium in Wet Flue Gas Desulfurization (WFGD) process is still unclear and even in controversial, impeding the development of selenium removal technologies. This research has found that the selenite in simulated slurry could be reduced by SO while selenate has not been affected. Characterization methods including X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) were used to provide an evidence that the product of the reduction reaction is amorphous elemental selenium. Meanwhile, the influences of other gaseous components, pH, temperature and SO in simulated slurry has also been considered in this research. It is found that with the increase of SO concentration in flue gas, the reduction of selenite increased and the reduction reaction is an exothermic reaction. Meanwhile, the oxidation effect of SO competes with the reduction effect of SO. This study introduced the influence of flue gas into the research of the conversion of selenium in FGD slurry and indicate the effect of flue gas on the potential emission treatment techniques of selenium in FGD slurry.
硒是燃煤电厂排放的有害微量元素之一。硒在湿法烟气脱硫（WFGD）过程中的分布仍不明确，甚至存在争议，这阻碍了硒去除技术的发展。本研究发现，模拟浆液中的亚硒酸盐可被SO还原，而硒酸盐不受影响。采用X射线衍射（XRD）和X射线光电子能谱（XPS）等表征方法证明还原反应产物为非晶态元素硒。同时，本研究还考虑了模拟浆液中其他气态成分、pH值、温度和SO的影响。研究发现，随着烟气中SO浓度的增加，亚硒酸盐的还原量增加，且还原反应为放热反应。同时，SO的氧化作用与SO的还原作用相互竞争。本研究将烟气的影响引入到FGD浆液中硒转化的研究中，并指出了烟气对FGD浆液中硒潜在排放处理技术的影响。
