【摘要】 烧结烟气经氨法脱硫后,吸收液中含有Fe3+等金属离子,随着工艺循环运行,Fe3+浓度逐渐升高,副产物硫酸铵质量变差。为研究Fe3+对氨法脱硫工艺中氧化和结晶的影响,设计了亚硫酸铵氧化实验和硫酸铵结晶实验。结果表明:Fe3+对亚硫酸铵氧化有催化作用。在亚硫酸铵初始浓度为0.6 mol/L,pH为5.0,Fe3+浓度为0.01 mol/L时,亚硫酸铵氧化效果最好,SO42-转化率为87.67%。在硫酸铵结晶实验中,通过XRD及SEM对硫酸铵结晶进行表征分析,在Fe3+对晶体特定晶面的抑制作用以及Fe(OH)3胶体絮凝作用下,当Fe3+浓度达到0.02 mol/L时,硫酸铵晶体无法正常结晶。吸收液中Fe3+浓度应控制在低于0.02 mol/L。更多还原

【Abstract】 Absorbing liquid has contained Fe3 +and other metal ions after sintering flue gas ammonia desulfurization. With the desulfurization cycle operation,the concentration of Fe3 +gradually increased,the quality of ammonium sulfate get worse. The ammonium sulfite oxidation experiments and ammonium sulfate crystallization experiments were designed to study the impact of Fe3 +. The results show that the ammonium sulfite oxidation was catalyzed by Fe3 +. When the initial concentration of ammonium sulfite was 0. 6 mol / L,the pH value was 5. 0,and the concentration of Fe3 +was 0. 01 mol / L,the effect of ammonium sulfite oxidation was best, the conversion rate of SO2-4was 87. 67%. The ammonium sulfate crystals was characterized by XRD and SEM,the result show that the crystals ’ specific plane were inhibited by Fe3 +,and by the flocculation of colloidal Fe( OH)3. When the concentration of the ferric ion was 0. 02 mol / L,the crystals cannot be normally cyslallized. The concentrations of Fe3 +should be controlled below 0. 02 mol / L in the absorbing liquid.更多还原