载锰飞灰吸附剂脱除SO2的实验研究

Experimental Study on SO2 Removal by Manganese-loaded Fly Ash Adsorbents

采用溶胶凝胶法制备脱除SO2用载锰飞灰吸附剂,并借助固定床评价系统对其脱硫性能进行测试。实验结果表明,吸附剂WNa(2)5Br Mn(3)100具有最高的脱硫能力,其本质原因是:NaBr在飞灰水化过程可以增强NaOH对飞灰表面玻璃体的破坏,生成水溶性胶体Na2SiO3,利用具有氧化性的Mn组分负载,Mn与Na2SiO3的共同作用可以显著增强吸附剂的脱硫性能,NaOH和Mn(NO3)2存在最佳添加量;溶胶温度会通过影响吸附剂的晶体结构来影响吸附剂的脱硫性能,溶胶温度越高其脱硫能力越强,最佳溶胶温度为100℃;飞灰吸附剂的粒径会通过影响其孔结构参数而影响对SO2的脱除能力,本实验中最佳粒径范围为270~150mm;根据载锰飞灰吸附剂自身特性,可用研磨溶胶的方法使其再生。

In this paper, the manganese-loaded fly ash adsorbents for SO2 removal were prepared by sol-gel method,and their desulfurization performance was tested by fixed bed evaluation system. The experimental results show that the adsorbent WNa(2)5 BrMn(3)100 has the highest desulfurization ability. The essential reason is as follows:First, during the hydration process of fly ash, NaBr can enhance the damage to vitreous shell of fly ash by NaOH, and form water-soluble gel of Na2SiO3, which is conducive to load oxidizing Mn component. The coaction of Mn and Na2SiO3 can significantly improve removing SO2 ability of adsorbents. The sol temperature affects SO2 removal performance by changing the crystal structure of fly ash adsorbents. The higher sol temperature results in the better desulfurization ability and100℃ is the optimal sol temperature in this experiment. The particle size of fly ash adsorbents influences the removal capacity of SO2 by the pore structure parameters, and the optimal particle size range is 270~150mm. According to the characteristics of the manganese-loaded fly ash adsorbent, it can be regenerated by the combination of grinding and sol.