(NH4)2S吸收净化冶炼烟气中SO2回收硫资源的方法

采用(NH₄)₂S溶液吸收净化高浓度SO₂烟气,得到(NH₄)₂S₂O₃和NH₄HSO₃的混合溶液并转移至高压反应釜中,控制反应条件,两种物质发生自氧化还原反应,生成硫磺和(NH₄)₂SO₄.实验考察了吸收SO₂过程和自氧化还原过程的影响条件,结果表明:在pH=3～7,SO₂气体流速300 ml·min^-1,(NH₄)₂S浓度为0.2～1.2 mol·L^-1,常温条件下,烟气中二氧化硫的吸收率达到99.8%以上,且无H₂S生成;在pH=2.5～3.0,温度为130℃条件下,反应进行1 h,硫磺收率达到95%以上,溶液经过蒸发结晶得到(NH₄)₂SO₄.用X射线衍射(XRD)和X射线荧光光谱(XRF)对硫磺和硫酸铵进行表征分析,结果表明:硫磺的纯度为99.14%,硫酸铵中氮元素含量为23.6%.

SO2 removal from simulated smelting gas with (NH4)2S and sulfur recycling

SO₂ in simulated smelting gas was absorbed by (NH₄)₂S solution, to obtain a mixed solution of (NH₄)₂S₂O₃ and NH₄HSO₃. After that the mixed solution was transferred into a special high pressure reaction kettle, and sulfur and ammonium sulfate were generated through the REDOX reaction under controlled conditions. The influence of SO₂ absorption process condition and REDOX process condition were investigated. Under the condition of pH=3-7, SO₂ flow velocity of 300 ml·min^-1, normal temperature, (NH₄)₂S solution concentration of 0.2-1.2 mol·L^-1, absorption efficiency of SO₂ reached more than 99.8% and H₂S was not produced. Under the condition of pH=2.5-3.0, reaction temperature 130℃, sulfur recovery rate could reach more than 95% after one hour of reaction. Ammonium sulfate could be obtained through evaporation crystallization. Sulfur and ammonium sulfate generated during reaction were characterized by X-ray diffraction (XRD) and X-ray fluorescence (XRF). Purity of sulfur was 99.14% and percentage of nitrogen in ammonium sulfate was 23.6%.