Patent GB-1050550-A (GB)
Abstract: 1,050,550. Hydrocyclones. DORR-OLIVER Inc. May 25, 1964 [May 29, 1963], No. 21436/ 64. Heading B2P. A hydrocyclone comprises a vortex chamber 26, Fig. 1, having at one end a substantially conical member 11 and at the other end a transverse annular wall 24 with a tubular vortex finder 25 extending towards the member 11 coaxially therewith and providing an annular feed inlet zone 27 to which feed mixture is supplied through a tangential inlet 28 an overflow receiving chamber 31 having a tangential outlet 31a, and a closed underflow receiving chamber 18 surrounding the member 11 and provided with a valved conduit 19 for the removal of underflow material. The apparatus is particularly adapted to separate water and grit from crude oil and is pressureoperated, pressure gauges being provided at 43, 44 and on the feed inlet pipe and the outlet 31a being connected to a cleaned crude oil pressure line. The apex of the conical member 11 has a cylindrical extension 13 provided with a tangential outlet 15 discharging grit and water into the chamber 18. Any oil entrained in the chamber 18 is returned to the vortex chamber through a pipe 32 extending from the upper region of chamber 18 into the apex of the conical member 11. A control device 33 governed by a float member 34 operating in an open-ended vertical cylinder 35 maintains the water-oil interface in the chamber 18 between upper and lower limits or at a suitable predetermined level "L" by automatically actuating the valve 20 in conduit 19 to eliminate grit and water from the chamber 18 when required. A number of valved water supply connections 41 are provided whereby flush water may be admitted to facilitate grit removal or whereby make-up water can be supplied when the oil-water interface drops too low or when insufficient water is available in order to prevent escape of oil with the grit discharge. In a modification, Fig. 4 (not shown), the apparatus is arranged vertically and the conical' member 47 is welded in the cylindrical shell 46 which is constituted by a single cylinder instead of a two-part one as shown in Fig. 1. The oil is returned from the underflow receiving chamber by a generally U-shaped tube 60 wholly located within the chamber. Alternatively, the return pipe 63, Fig. 5 (not shown), has a section 63a extending outside the apparatus and provided with a control valve 67. A valved flush-water pipe connection 68 is provided to flush out the pipe section 63b with valve 67 closed. In this case, the underflow from the apex of the conical member is directed against a baffle plate 64 to be discharged radially into the chamber 18a. In a modification, of Fig. 5, Fig. 6 (not shown), the return pipes are eliminated and the oil is returned through a central orifice 70 in the baffle plate 64' which may be tilted at an angle to the horizontal. A straight length of tube may extend from the orifice into the discharge neck 65'. Radial or curved vanes may be provided in the space between the neck 65 and the baffle plate 64 with their faces parallel to the cyclone axis to absorb swirl of the apex discharge and allow the solids to gravitate to the bottom of the chamber 18. The vanes may terminate short of the chamber wall or have their ends connected thereto. In a further modification, Fig. 7 (not shown), the neck 71 of the conical member has a tangential outlet 72 and an oil return orifice 73 in its end plate 74. In a still further modification, Fig. 9 (not shown), a valved oil-return pipe 78 connects the underflow chamber with a Venturi-shaped section of the feed supply pipe 79. The apparatus may also be so designed that, when efficient grit operation is achieved in the underflow receiving chamber, oil may be allowed to return from the clear oil region therein into the separated oil coming from the vortex finder.