GB370072A - Improvements in or relating to floating outlets for drawing off supernatant liquid - Google Patents

Abstract

370,072. Gravity-separation apparatus. WHITEHEAD & POOLE, Ltd. and NORRIS, F., Milltown Street, Radcliffe, near Manchester. Jan. 14, 1931, No. 1245. [Class 46.] Apparatus for drawing off supernatant liquid comprises a swinging conduit arm having an inlet which moves angularly about the axis of movement of the arm and is maintained by a float partly below and partly above the surface of the supernatant liquid, the depth to which the inlet extends below the surface being constant. The lower end of the conduit 1 is pivotally connected to an elbow pipe 5 and a valve 6 leading to an outflow conduit. The rectangular upper end is fastened to a threechambered hollow cylinder 7 so as to project radially through an opening 11 into a central chamber between two end chambers 10, which form float chambers. The large aperture 11 is so arranged that it remains below the surface of the liquid in all normal positions of the conduit 1, and another aperture 12 similarly remains above the surface of the liquid, so that scum is prevented from entering the cylinder 7. The side 14 of the conduit 1 terminates at the centre line of the cylinder, or in horizontal alignment with the centre line, and the opposite side 15 terminates at a level which is always above the centre line, the upper end of the conduit being inclined, as shown. The inlet aperture 16 may be adjustable in width and its lower extremity coincides with the upper edge of the side 14, so that its depth below the surface of the liquid is constant, and therefore the head of the liquid causing a flow is constant. This constant depth may be adjusted by inserting liquid or small slots into the float chambers through openings normally closed by screw plugs 17.