煤泥絮体特征参数提取及其动态变化规律  

Extraction of characteristic parameters of coal slime flocs and its dynamic change

作　　者：焦小淼 刘文礼[1] 杨宗义[1] 张振亚[1] 

机构地区：[1]中国矿业大学(北京)化学与环境工程学院,北京100083

出　　处：《矿业科学学报》2017年第5期503-510,共8页Journal of Mining Science and Technology

基　　金：中央高校基本科研业务费专项资金(2010YH11)

摘　　要：针对煤泥絮体图像处理时存在的模糊絮体识别困难问题,提出一种基于絮体清晰度自动剔除模糊絮体提取絮体特征参数的方法。对比常规阈值分割法和应用图像处理软件手动处理法得出,该方法可快速、准确提取絮体特征参数。通过试验,研究了不同搅拌转速和不同絮凝剂用量下煤泥絮体特征参数随絮凝过程的动态变化规律。结果表明:煤泥水絮凝过程可以分为三个阶段,即絮体快速长大阶段、破碎阶段及动态平衡阶段;搅拌转速越大,絮体快速长大阶段用时越短,平衡阶段对应的絮体当量直径均值越小;在絮凝剂用量为3 mg/L时,搅拌转速为152 r/min条件下形成的煤泥絮体分形维数最小(1.89±0.01),搅拌转速为217 r/min条件下形成絮体分形维数最大(2.17±0.03);在搅拌转速为152 r/min时,随着絮凝剂用量增大,煤泥絮体当量直径均值在絮凝剂用量为4 mg/L时达到最大值,煤泥絮体分形维数值由1.81±0.01增大到2.01±0.03。A fully-automated image processing script based on clarity value of floc was developed to solve the existing problems of fuzzy coal slime flocs difficulties in accurate identification.In the procedure,out-of-focus flocs were automatically removed to attain more precise floc characteristic parameters.The resulting measured and the characteristic parameters were compared to floc measured through compare with manual processing method using image processing software and conventional threshold segmentation method,the automated method was able to accurately measure the floc characteristic parameters quickly by correctly sizing in-focus flocs and removing out-of-focus flocs.The dynamic changes of characteristic parameters of slime floc were studied at different stirring speeds and different dosage of flocculants by applying the fully-automated image processing script during flocculation process.The results showed that,the process of slime water could be divided into three stages:rapid growth stage,crushing stage and equilibrium stage,and the larger the stirring speed,the shorter the floc growth stage and the smaller the mean value of floc equivalent diameter;The two-dimensional fractal dimension was found ranging from(2.17 ± 0.03) to(1.89 ± 0.01),corresponding to flocs that were either relatively compact or loosely structured,at high(217 r/min) and low(152 r/min) stirring speed respectively with the flocculants dosage of 3 mg/L;The equivalent diameter of coal slime floc reached the maximum at the flocculants dosage of 4 mg/L,and the two-dimensional fractal dimension was found increasing from(1.81 + 0.01) to(2.01 + 0.03) with the increasing dosage of flocculants at the 152 r/min stirring speed.

关 键 词：煤泥 絮凝 分形维数 

分 类 号：TD94[矿业工程—选矿]