厢式压滤机的煤浆压滤脱水过程数学建模与数值模拟  

Mathematical Modeling and Numerical Simulation of Pressure Filtration and Dewatering of Coal Slurry in Chamber Filter Press

作　　者：万国顺 张大伟 宋伟 董琪[1] 贾玉玺[1] WAN Guo-shun;ZHANG Da-wei;SONG Wei;DONG Qi;JIAYu-xi(School of Materials Science and Engineering,Shandong University,Jinan 250061,China)

机构地区：[1]山东大学材料科学与工程学院,山东济南250061

出　　处：《高校化学工程学报》2018年第5期1171-1177,共7页Journal of Chemical Engineering of Chinese Universities

基　　金：德州市现代产业首席专家项目(DB20175124)

摘　　要：在厢式压滤机煤浆压滤脱水过程中,煤浆在滤室内的流动形态及滤饼的成型规律难以被直接观测,煤浆与滤饼对滤板的挤压效应难以直接在线监测,因此压滤脱水工艺参数的设置尚主要依靠经验。为解决这一问题,以厢式压滤机中煤浆压滤脱水过程为研究对象,分析了煤粒-水两相流的流动特性,建立了煤浆黏度与煤粒浓度、粒径等参数的关系模型,结果表明减小煤粒直径并优化颗粒形状及表面质量可有效提高煤浆流动性;应用ANSYSFluent数值模拟了压滤脱水过程,揭示了煤粒由出水口至进料口逐步积累的沉积成饼规律和压力场分布及其与煤粒浓度分布间的相关性,并进一步得出煤浆流变特性转变浓度为34%。研究结果为过滤参数设定及滤板几何结构优化、过滤效率提升等提供了重要的理论依据。During pressure filtration and dewatering processes of coal slurry in chamber filter press, flow status of coal slurry and filter cake formation cannot be observed directly, and the squeezing effects of coal slurry and filter cake on filter plates are difficult to be directly online monitored. Therefore, the setting of technological parameters for dewatering process is mainly dependent on experience. Dewatering process of coal slurry pressure filtration was investigated in this study, and two-phase flow characteristics of coal particle/water were analyzed. A model concerning coal slurry viscosity, coal particle concentration and particle size was established, and the model results show that reducing coal particle diameter and optimizing particle shape and surface can effectively improve slurry fluidity. Meanwhile, the dewatering process was numerical simulated by ANSYS Fluent and the results reveal that coal particles accumulate gradually from the outlet to inlet and the pressure distribution has obvious correlation with the distribution of particle concentration. Furthermore, the rheological properties of coal slurry changes at a critical concentration of 34%. The results provide theoretical guideline for setting technological parameters of dewatering process, optimizing geometrical structures of filter plate and improving filtration efficiency.

关 键 词：煤浆 两相流 压滤 滤饼 

分 类 号：TQ028.53[化学工程] TQ051.85