GB1429272A - Method of controlling the minimum load of a lamella sedimenta tion apparatus - Google Patents

Abstract

1429272 Lamella sedimentation apparatus REDERI AB NORDSTJERNAN 2 March 1973 [3 March 1972] 10240/73 Heading BID A lamella sedimentation apparatus for separating solid from liquid comprises at least one package comprising spaced apart parallel plates 1 with outlet tubes 3 centrally placed between each pair of plates for clarified liquid and carried upwardly to a level above an outlet channel 11 (Fig. 6, not shown) of the package into which channel the tubes empty. The tubes are arranged such that the height of their outlets varies and at increasing flow rates clarified liquid is delivered through an increasing number of outlet tubes into the outlet channel 11 to thus maintain an acceptable flow rate between each pair of plates. A typical package contains 50 tubes with the first 17 outlet tubes opening at the same height, (Fig. 7 not shown) and each of the suoceeding tubes or groups of succeeding tubes being terminated at a height slightly above its predecessors. A plurality of such packages may be used in parallel, the number of packages being brought into operation depending on the amount of liquid to be treated. The switching into or out of use of a package may be controlled by a pivoted shutter at the outlet channel, the position of which shutter depends on the water level in the outlet channel as in Figs. 13-16 (not shown), or by sensing the water level at the inlet and actuating a motor controlled shutter at the outlet channel. The outlets of each package outlet channel 11 are connected to a further outlet channel common to all packages.