磷酸钠法烟气脱硫富液抗氧化性研究

Research on oxidation resistance of SO_2-riched sodium phosphate solution

通过分析磷酸钠法烟气脱硫机理和亚硫酸钠氧化反应机理,采用动力学方法,设计正交实验,考察了亚硫酸钠浓度、空气流量、磷酸浓度、溶液pH值和温度5个因素对磷酸钠脱硫富液中亚硫酸钠氧化反应速率的影响。结果表明,各因素对亚硫酸钠氧化速率影响的显著性顺序为：c（Na2SO3）〉cP〉pH〉T〉G。磷酸钠吸收剂能够抑制亚硫酸钠的氧化。实验操作范围内,磷酸钠脱硫富液中亚硫酸钠氧化速率为0.001 16mol·L-1·h-1~0.018 75mol·L-1·h-1。研究结果为磷酸钠烟气脱硫技术中硫酸钠的生成控制提供了理论指导。

By analyzing the mechanisms of flue gas desulfurization with sodium phosphate method and sodium sulfite oxidation,a dynamic method is used and an orthogonal test is designed.The influence of five factors of sodium sulfite concentration,air flow,phosphoric acid concentration,pH and temperature on oxidation rate of sodium sulfite in SO2-riched sodium phosphate.The analytical results indicate that the significant sequence of influence for each factor on the oxidation rate is：c（Na2SO3）〉cP〉pH〉T〉G.The absorbent of sodium phosphate could inhibit the oxidation of sodium sulfite.During the operational range,the oxidation rate of sodium sulfite is between 0.001 16mol·L-1·h-1~0.018 75 mol·L-1·h-1.The results could provide theoretical directions for the control of sodium sulfate production in flue gas desulfurization with sodium phosphate buffer.