三水-一水软铝石型铝土矿原矿浆流变性研究

Research on Rheology of Gibbsite-Boehmite Bauxite Slurry

以难处理三水-一水软铝石型高硅铝土矿为研究对象,采用Thermo公司生产的RS600型流变仪,研究了温度、固含、碱浓度以及粒度等因素对此类铝土矿原矿浆流变性的影响。结果表明:原矿浆的流变性随温度、固含、苛性碱浓度的升高及矿石粒度的细化而恶化;当固含低于1 050 g/L时,原矿浆为宾汉姆流体,当固含高于1 050 g/L时,转化为幂率流体,原矿浆屈服应力急剧升高;当苛性碱浓度低于180 g/L时,原矿浆为宾汉姆流体,苛性碱浓度高于180 g/L时,逐渐转化为幂率流体;相同固含条件下,-180μm原矿浆的屈服应力约是-850μm原矿浆的3倍。从便于输送、降低能耗的角度考虑,原矿浆制备的温度不应太高,固含应低于1150 g/L,苛性碱浓度最好低于180 g/L。

Influence of temperature, solid content, alkali concentration and particle size distribution on rheology of gibbsite-boehmite bauxite was investigated by using RS600 rheometer of Thermo Company. Results show that rheology of bauxite deteriorates with increased temperature, solid content and alkali concentration, as well as downsized particles. Bauxite slurry is Bingham fluid when solid content is lower than 1 050 g/L, and becomes power-low fluid as solid content higher than 1 050 g/L, with yield stress increasing dramatically. Also, bauxite slurry is regarded as Bingham fluid at an alkali concentration lower than 180 g/L, then gradually changes into power-low fluid with alkali concentration increased to over 180 g/L. Besides, yield stress of bauxite slurry with particle size -180 p,m is three times that of bauxite slurry with particle size -850 μm at the same solid content. It is concluded that bauxite slurry should be prepared at a moderate temperature, with solid content less than 1 150 g/L and caustic alkali concentration lower than 180 g/L for convenient transportation and energy saving.