Overflow rate of high-rate settlers

After a concise overwiev of the theoretical principles of high-rate settlers proposed by Yao, the parameters are defined that enable a comparison between the overflow rate of various high-rate settling systems and of conventional settlers. A system of parallel plate settlers, a system of circular tube settlers, and a system of square conduits settlers are analyzed. On the basis of the performed analysis, the overflow rate coefficient, C-r, as a function of high-rate settling system, angle of inclination of the settler and the relative length of the settler, is defined. The C-r value is less than 1 and more than 0. As to the value of the overflow rate coefficient, it is shown that the overflow rate of high-rate settlers is C-r(-1) times less than that for conventional settlers.