利用颗粒成像技术对硫酸铝形成的高岭土和腐殖酸絮体在破碎后重新生长形成的絮体结构动态变化进行了研究。结果表明，在絮体生长-破碎-再生长过程中，腐殖酸存在时会导致絮体分形维数减小。絮体在生长过程中的分形维数随着粒径增加从1.60增加到1.80，破碎后絮体分形维数重新回到1.60。絮体重新生长形成的絮体的分形维数跟破碎强度有关，较长时间破碎形成的絮体分形维数没有明显变化，短时间破碎形成的絮体分形维数和生长阶段稳定阶段一致。絮体破碎后重构不是生长阶段絮体分形维数增加的原因，而是跟絮体分形尺度不变性及存在多级结构有关。%Characteristics of changes in fractal structure of alum flocs during the floc growth-breakage-regrowth were investigated. The results showed that the fractal dimensions of alum flocs decreased with the increasing humic acid concentration. The fractal dimension increased from about 1.60 to 1.80 during floc growth, decreased back to 1.60 after floc breakage. The fractal dimension of alum flocs after floc regrowth had a close relationship with breakage time. The fractal dimension of alum flocs for 15 minutes breakage had no significantly change during floc regrowth, increased to about 1.80 for 30 seconds breakge. The changes in fractal dimension did not result from the floc restructuring after floc breakage, but from the scale invariance and multi-level structure of fractal aggregates.
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