煤泥絮凝过程聚并-破碎效率研究  

Aggregation-deaggregation efficiency of coal slime flocculation

作　　者：段家奇 叶贵川 樊玉萍[1] 马晓敏 董宪姝[1] DUAN Jia-qi;YE Gui-chuan;FAN Yu-ping;MA Xiao-min;DONG Xian-shu(College of Mining Engineering,Taiyuan University of Technology,Taiyuan 030024,China)

机构地区：[1]太原理工大学矿业工程学院,山西太原030024

出　　处：《煤炭工程》2023年第1期156-161,共6页Coal Engineering

基　　金：国家自然科学基金青年基金(52104260);国家自然科学基金面上项目(52074189);山西省应用基础研究计划青年基金资助项目(201901D211034);国家基金重点国际(地区)合作研究项目(51820105006)。

摘　　要：为了揭示流体剪切对微细煤泥絮凝过程破碎-聚并效率的影响规律,在不同剪切速率和搅拌桨离地高度条件下进行煤泥絮凝试验,并采用聚焦光束反射测量仪实时测定絮凝过程中絮团尺寸变化情况,以絮团平均粒径增长率间接反映絮凝过程聚并-破碎效率。研究结果表明:絮团平均粒径增长率可以反映煤泥颗粒絮凝过程的聚并-破碎效率,依据增长率的变化情况,煤泥絮凝过程可分为聚并阶段、破碎阶段和亚稳定阶段;剪切速率对煤泥絮凝行为有显著影响,在G<35.89s-1时增大剪切速率,有利于聚并效率和亚稳定阶段时絮团平均粒径的增加;但过高的剪切速率(G>53.83s-1)将产生较高的湍流耗散率,使絮团破碎效率增大;搅拌桨离地高度对煤泥的絮凝行为有一定影响,在h/H<1/3时,适当增加搅拌桨离底高度有益于煤泥颗粒生成更大的絮团。In order to reveal the influence of fluid shear on the aggregation-deaggregation efficiency of micro-fine coal slurry flocculation, flocculation tests were carried out under different shear rate and stirring position, in which FBRM was used to measure the floc size, and the average floc size growth rate was proposed to indirectly reflect the aggregation-deaggregation efficiency.According to the findings, the average floc size development rate can indirectly indicate the aggregation-deaggregation effectiveness of the flocculation process;the process can be divided into three stages according to the change in growth rate: aggregation, deaggregation and sub-stable;increasing the shear rate within a certain range(G<35.89s-1) is beneficial to the aggregation efficiency and the size growth of flocs in the sub-stable stage;however, too high shear rate(G>53.83s-1) will produce a high turbulent dissipation rate and accelerate the floc deaggregation;stirring position has a certain effect on the flocculation behavior of coal slurry, when h/H<1/3, the formation of bigger flocs from coal slurry particles benefits from higher stirring position.

关 键 词：煤泥水絮凝 流体剪切 聚并效率 FBRM 剪切速率 搅拌桨 絮团 

分 类 号：TD94[矿业工程—选矿]