针对磷尾矿中镁资源浪费问题，以模拟SO₂烟气为提取剂提取磷尾矿中的镁元素。通过单因素试验和正交试验考察反应温度、磷尾矿浆固液比、反应pH、烟气中SO₂质量浓度、烟气流速对SO₂烟气提取磷尾矿中镁元素的影响，得各因素影响大小为：固液比 > 气体流速 > 反应温度 > pH > 进口SO₂质量浓度，并确定了较适宜的反应条件：矿浆固液比为1%、反应pH为5、气体流速为600 mL/min、进口烟气中SO₂质量浓度为8 500 mg/m³、反应温度为50℃。在该条件下反应120 min后，镁元素的浸出率可达97.74%。此外，通过强化研究发现，热处理及加入添加剂能有效提高磷尾矿中镁元素的浸出效率。

Simulated flue gas containing SO₂ is used to extract magnesium from phosphorus tailings,in order to save magnesium resource.Influences of reaction temperature,solid-liquid ratio,reaction pH,SO₂ concentration in flue gas and the flow speed of flue gas on the extraction of magnesium from phosphate tailings are studied through single factor experiment and orthogonal test.The results show that solid-liquid ratio shows the biggest influence,followed by gas flow rate,reaction temperature,reaction pH and SO₂ concentration in flue gas.The optimum reaction conditions are determined as follows:solid-liquid ratio is 1%,pH=5,gas flow speed is 600 mL·min^-1,SO₂ concentration in flue gas is 8 500 mg·m^-3,and reaction temperature maintains at 50℃.Under the optimum conditions,the leaching rate of magnesium can reach 97.74% in 120 min of reaction.In addition,it is found through intensive experiment that both calcination and the addition of additives can effectively improve the leaching rate of magnesium from phosphorus tailings.

张慧芳(1994-),女,硕士研究生,研究方向为大气污染控制,821713931@qq.com