DYNAMIC MICROFILTRATION OF HIGH VISCOSITY SURRIES CONTAINING ULTRAFINE SUSPENDED SOLIDS

本文分析了固-液混合物产生高度可压缩滤饼和/或高粘度滤液的动态微滤机理。本文提出了高通量过滤的设计和评价依据，即由于对污垢层有强大的清扫力，动力学效应显著提高了含有超细悬浮液的难分离体系的过滤速率。1）由油滴组成的污垢层具有很高的可压缩性，这对污垢层的清除产生很大的影响，并使通量下降复杂化以响应不同的操作条件。如果考虑到稳态通量取决于作用在薄滤饼上的剪切应力以及恒压过滤系数，则可以评估这些滤饼可压缩性效应。这种可压缩性效应也是分析中的一个严重限制。 关于我们 2）含亚微米悬浮固体的O/W乳状液的死端微滤特性很大程度上取决于由于油和/或固体含量的不同而引起的滤饼可压缩性的显著变化。本文提出的经验方法可以估计最佳过滤条件与保持滤液通量最大的固体含量之间的关系，通过定义由磁场强度和固体磁化强度组成的控制参数，可以分析磁性悬浮固体的高梯度磁沉降行为。磁性元件上的细颗粒层所产生的高磁性增强了以相当高的速率进料的浆料中悬浮物的去除。在其过滤室中具有附加颗粒床的旋转圆筒动态过滤产生比传统操作中遇到的小得多的水力滤饼阻力。研究结果可作为高速微滤设计的依据。少

The dynamic microfiltration mechanisms of the solid-liquid mixtures producing highly compressibie cake and/or highly viscous filtrate were analyzed for both rotating-and crossflow-membrane filtration. A basis for the design and evaluation of high flux filtration was proposed based on the fact that due to a powerful sweeping force acting on fouling-layr, the dynamic effects yield remarkable improvements in the filtration rate of poorly separable systems containing superfine suspensoids.1) The high compressibility of a fouling layr composed of oil droplets exerts a great influence on the sweeping away of the layr and complicates the flux decline in response to different conditions of operation. These cake compressibility effects can be evaluated if one considers that the steady-state flux depends both on the shear stress acting on the thin-cake as well as on the coefficient of constant pressure filtration. Such compressibility effects are also a serious constraint in the analysis of the … More dynamic filtration performance of solid-liqiud slurry.2) The dead-end microfiltration characteristics with the O/W emulsion containing submicron suspended solids depend heavily on the marked changes in cake compressibility due to different oil and/or solid contents. The empirical method proposed here allows the estimation of the relationships between the optimum filtration conditions and the solid contents keeping the filtrate flux at a maximum.The high gradient magnetic settling behaviors of magnetic suspended solids can be analyzed by defining a controlling parameter composed of the strength of the magnetic field and the magnetization of the solids. The high magnetism created by a fine-sized solids layr on the mangetic element enhances the removal of suspensoids from slurry fed at a fairly high rate.The rotating cylinder dynamic filtration with an additional particle bed in its filter chamber yields much smaller hydraulic cake-resistance than that encountered in traditional operations. The results may be efficient as a basis for the design of high rate microfiltration. Less