复合助滤剂对煤泥表面改性及滤饼结构的影响  

The influence of composite filter aid on the surface modification and filter cake structure of coal slime

作　　者：陈茹霞 樊玉萍[1] 董宪姝[1] 马晓敏 冯泽宇 CHEN Ruxia;FAN Yuping;DONG Xianshu;MA Xiaomin;FENG Zeyu(College of Mining Engineering,Taiyuan University of Technology,Taiyuan,Shanxi 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：《中国矿业大学学报》2021年第6期1195-1203,共9页Journal of China University of Mining & Technology

基　　金：国家自然科学基金国际(地区)合作与交流项目(51820105006);国家自然科学基金面上项目(51674174);国家自然科学基金青年科学基金项目(52004178);山西省重点研发计划(国际科技合作)项目(201803D421104);山西省科技成果转化引导专项项目(201904D131024)。

摘　　要：为改善滤饼孔隙结构,强化煤泥脱水效率,设计并采用SiO_(2)基复合助滤剂对煤泥进行助滤试验,从颗粒表面性质、滤液性质和滤饼三维结构等多方面分析了助滤机理.过滤试验结果表明:SiO_(2)基复合药剂(GH型)提高了煤泥水过滤速度,降低了滤饼比阻,滤饼水分从32.5%降低至28.1%.表面张力测试结果表明:SiO_(2)基复合药剂可以降低滤液表面张力,减小水分排出所需要的压差.扫描电子显微镜-能谱仪(SEM-EDS)分析和接触角测试表明:疏水性纳米级SiO_(2)(Nano-SiO_(2))球和十八烷基三甲基氯化铵(STAC)可以协同提高煤泥颗粒的疏水性.X射线计算机断层扫描(CT)结果表明:加入微米级SiO_(2)(Micron-SiO_(2))球后,滤饼孔隙率从1.54%升高到6.67%;滤饼孔隙和吼道数量、孔吼配位数增大,提高了滤饼孔隙的连通性;滤饼孔吼半径比从1.18降低到1.09,降低了水分迁移过程中的毛细阻力,说明Micron-SiO_(2)球对煤泥滤饼起到了骨架支撑作用,显著改善了过滤效果.To improve the pore structure of the filter cake and enhance the dewatering efficiency of coal slime,a SiO_(2)-based composite filter aid was designed and used in the filtration tests.The filtration mechanism was analyzed from various aspects such as particle surface properties,filtrate properties,and the three-dimensional structure of filter cake.Results of the filtration test show that the filtration rate increases,the filtration specific resistance decreases and the filter cake moisture reduces from 32.5%to 28.1%in the presence of the SiO_(2)-based composite reagent(GH type).The surface tension test results show that the SiO_(2)-based composite rea-gent could reduce the surface tension of the filtrate and decrease the pressure difference re-quired for water discharge.SEM-EDS analysis and contact angle test show that hydrophobic Nano-SiO_(2)spheres and stearyl trimethyl ammonium chloride(STAC)could synergistically im-prove the hydrophobicity of coal slime particles.X-ray computed tomography(CT)results show that the porosity of the filter cake is increased from 1.54%to 6.67%after adding Mi-cron-SiO_(2)balls.The number of filter cake pores and channels,as well as the coordination num-ber of pores are increased,which improves the connectivity of filter cake pores.The pore radi-us ratio of the filter cake is reduced from 1.18to 1.09,which reduces the capillary resistance in the process of water migration,indicating that the Micron-SiO_(2) ball plays a framework support for the filter cake and significantly improves the filtering effect.

关 键 词：煤泥脱水 复合药剂 骨架构建体 滤饼三维结构 

分 类 号：TD926[矿业工程—选矿]