机械磨制备碳酸氢钠超细粉体

Preparation of Superfine Sodium Bicarbonate Powders by Using Impact Mill

采用LNI-180A型机械磨对碳酸氢钠干粉进行超细加工,分析讨论了不同分级机转速下制备的碳酸氢钠细粉的粒度、比表面积、电耗以及形貌特征。结果表明:机械磨分级机转速由540 r/min增至1 050 r/min时,所制备的碳酸氢钠细粉粒度d90从45.630μm减小至13.090μm,比表面积从0.86 m2/g增大到1.83 m2/g,产量减少65%,单位电耗增加至2.57倍;综合考虑粒度与能耗,得到LNI-180A型分级式机械磨制备碳酸氢钠细粉的最优分级机转速为750 r/min,其粒度d90为24.950μm,比表面积为0.94 m2/g,单位电耗为70.66 k W·h/t。粉碎后的碳酸氢钠细粉呈层状或多孔状结构,颗粒大小均匀,具有良好的分散性,是良好的灭火材料和脱硫剂。

Superfine sodium bicarbonate（Na HCO3） powders were grinded by using LNI-180 A impact mill their particle size,specific surface area,power consumption and morphology were discussed under different classifier speed. The results showed that with the decreasing of classifier speed from 1 050 r/min to 540 r/min,the particle size（d90） of the superfine powders decreased from 45. 630 μm to 13. 090 μm,the specific surface area increased from 0. 86 m^2/g to 1. 83 m^2/g,while the yield reduced by 65%,moreover,the energy consumption decreased by 2. 57 times. Considering the particle size and energy consumption,the optimum classifier speed of LNI-180 A impact mill for preparation of Na HCO3 powers was 750 r/min,d90 was 24. 950 μm,specific surface area was 0. 94 m^2/g,unit power consumption was70. 66 k W·h/t. The grinded NaHCO_3 powders exhibit lamellar or porous structure and have a uniform distribution and good dispersion,which is a good fire extinguishing material and desulfurizer.