CALCULATION OF THE FILTRATION CHARACTERISTICS OF SMALL HYDROCYCLONES WITH FINELY DISPERSED SUSPENSIONS.

To determine the separating efficiency of hydrocyclones and to evaluate quantitatively the carryover of solid particles through the mixing opening, the inlet suspension and the clarified and thickened fractions were analyzed. Samples were filtered through dense ash-free filter papers, and the residue was ignited in a muffle furnace, cooled and then weighed on an analytical balance to an accuracy of 0. 1 mg. The concentration of the solid material in the clarified fraction was then determined with the aid of an apparatus based on the measured attenuation of ultrasonic waves passing through a suspension and its relation to the concentration and nature of the solid phase. In order to evaluate the particle size distribution of the initial suspension and the clarified fraction, rapid sedimentation analysis was used. The productivity of the hydrocyclones by fractions was measured for various feed pressures. Examination of the data obtained from the inspection of many hydrocyclones operating under industrial conditions, showed that the particles carried over with the clarified fraction were always greater by a factor of 1. 5 to 2. 0 than the calculated size.