精密ろ過膜による加工液のろ過 : 第2報,クロスフローろ過について

In the first report, an experimental analysis of filtration of machining fluids was investigated. The influences of turbulence on the surface of membrane on the permeation flux were clarified. Turbulence was created by a stirring bar, as the turbulence promoter, and the experiment was carried out using dead-end filtration. It was consequently determined that creating turbulence on the surface of a membrane is an effective way to increase the permeation flux. In this report, a fundamental analysis is made on the influences of turbulence on the surface of a membrane on the permeation flux. A single circular flat plate, as the turbulence promoter, is set on the front edge of a cartridge membrane. Cross-flow filtration of machining fluids is carried out using a cellulose-type membrane for microfiltration, with a pore diameter of 1μtm. The effects of blockage ratio of the turbulence promoter, feed concentration on permeation flux and solute rejection are examined. The behavior of this flux is analyzed by resistance of the membrane itself, the cake layer and the plugging. A modified standard filtration model is applied to calculate the time-decline curve of the permeation flux. In comparison with experimental results, calculated ones demonstrated that this model could effectively predict the time-decline curve of the permeation flux under various operating conditions.