School of Energy, Power and Mechanical Engineering, North China Electric Power University, Beijing, 102206, China.
China Huaneng Clean Energy Research Institute, China Huaneng Group, Beijing, 102209, China.
Environ Sci Pollut Res Int. 2020 Mar;27(9):9771-9779. doi: 10.1007/s11356-020-07604-y. Epub 2020 Jan 10.
High alkali-metal sulfate contents in ash from high-alkali coal are a result of the alkali metals' strong sulfur-capturing capacity. In this work, the effects of sulfates in ash on SO formation were investigated by adding alkali-metal sulfates (NaSO and KSO) to ash and performing experiments to simulate SO formation. The results show that NaSO and KSO addition significantly increased SO formation and the formation rate increased with increasing temperature. The formed SO concentration increased by 6.8 ppm (adding NaSO) and 6.3 ppm (adding KSO) at 1000 °C. These increases are the result of SO release from sulfate during the formation of aluminosilicates such as NaAlSiO (albite), NaAlSiO (nepheline), KAlSiO (kalsilite), and KAlSiO (feldspar) with the SiO and AlO in the ash. This was confirmed by X-ray diffraction (XRD) and thermodynamic calculation. In addition, increasing the SO concentration increased the SO concentration and decreased the SO conversion ratio. Graphical abstract Note: This data is mandatory.
煤灰中高碱性金属硫酸盐含量高是由于碱性金属具有很强的捕硫能力。在这项工作中，通过向灰分中添加碱性金属硫酸盐（Na2SO4 和 K2SO4）并进行模拟 SO 形成的实验，研究了灰分中硫酸盐对 SO 形成的影响。结果表明，添加 Na2SO4 和 K2SO4 显著增加了 SO 的形成，且随着温度的升高，形成速率增加。在 1000°C 时，SO 形成浓度分别增加了 6.8 ppm（添加 Na2SO4）和 6.3 ppm（添加 K2SO4）。这些增加是由于硫酸盐在形成硅铝酸盐（如钠长石（albite）、霞石（nepheline）、白榴石（kalsilite）和长石（feldspar））时释放出 SO，而灰分中的 SiO 和 AlO 参与了这一过程。这一点通过 X 射线衍射（XRD）和热力学计算得到了证实。此外，SO 浓度的增加会提高 SO 浓度，降低 SO 转化率。
