SiO_2添加剂对铝电解用炭间糊性能的影响

Effect of SiO_2 Additive on Properties of Ramming Paste for Aluminum Electrolysis

以电煅煤、熟碎、沥青焦为骨料,改质沥青和煤焦油为混合粘结剂,添加SiO_2制备铝电解用炭间糊,研究SiO_2含量对制备炭间糊基本性能、膨胀/收缩过程及微观结构的影响。结果表明,随着SiO_2含量的增加,糊料的灰分含量逐渐提高,表观密度和导电能力逐渐下降,耐压强度在24.11~34.33 MPa区间内呈无规律变化;热膨胀程度明显下降,炭化过程提前;SiO_2添加剂主要分布于骨料颗粒表面和粘结焦中。当SiO_2含量为4%时,膨胀/收缩率最优。

Ramming pastes were synthesized using calcined anthracite coal,baked scrap,coal derived pitch coke as aggregate,modified pitch and coal tar as binder and SiO2 powder as additive. The effect of SiO2 addition on the basic properties,expansion/shrinkage process and microstructure of ramming paste were investigated. The results show that as the SiO2 addition increased,the ash and electrical resistivity increased,while bulk density,volume expansion and carbonized temperature decreased. The compressive strength fluctuated in the range of 24. 11—34. 33 MPa. The SiO2 additive was mainly distributed on the surface of aggregate particles and binding coke. The expansion/shrinkage rate of ramming paste reached an excellent level when the addition of SiO2 is 4%.