Patent GB-1090978-A (GB)
Title: Multiple hydrocyclone unit and system incorporating the same
IPC: B04C3/04
Filed: 1965-01-25
Abstract: 1,090,978. Hydrocyclones, filters. DORR-OLIVER Inc, Jan. 25, 1965 [April 13, 1964], No. 3125/65. Headings B1D and B2P. [Also in Division F2] A multiple hydrocyclone unit comprises a cylindrical cyclone block 14 formed with a central feed receiving chamber 18 to which feed is supplied through at least one radial inlet duct 24. The chamber 18 has an open end at an end face F1 of the block and a closed end spaced from the other end face F2 of the block. A plurality of cyclonic bores 22 are formed in the block, as shown, or in inserts (38d), Fig. 5a (not shown) located in cylindrical bores (38c) in the block, and are spaced around the chamber 18. The cyclonic bores have relatively wide feed inlet end portions 22a communicating with the chamber 18 via channels 23 and relatively constricted underflow discharge end portions 22b providing underflow discharge openings. The underflow end portions may have straight cylindrical terminal portions (22c), Fig. 1a (not shown). A plate member 15 in sealing engagement with the end face F1 of the block is provided with vortex finders either in the form of inserts 26 pressfitted in bores in the plate member, as shown, or moulded integral with the plate member as at (35) in Fig. 7 (not shown). Closure members 16, 17 at opposite ends of the block are formed with recesses constituting respectively with the plate member 15 and with the end face F2 of the block overflow and underflow chambers 26a, 28 communicating with discharge pipes 12, 13 for the overflow and underflow respectively. In a modification, Fig. 7 (not shown) the lower closure member is integral with the cyclone block. The hydrocyclone unit may be used to classify solids suspended in a liquid medium according to size or specific gravity or for removing solids from a liquid. A screen member 29 may be inserted in the chamber 18 to prevent oversize particles from reaching, and thereby clogging, the cyclonic bores 22. The capacity of the unit may be varied by inserting one or more control rod members 37, Fig. 4, through the vortex finder(s) of one or more of the cyclonic bores for closing the underflow and overflow discharge openings. The control rod member or other form of stopper may be connected to a screw (38), Fig. 5 (not shown) passing through a bore in the closure member 16 and may extend downwards to close only the overflow opening. Tabs (40), Fig. 6 (not shown), may be inserted in grooves (41) in the end closure member adjacent each of the screws (38) to indicate which ones of the individual cyclones in the unit are in or out of operation. The cyclone unit may be made of stainless steel. In the case of insertable vortex finder members and insertable cyclone members, these may be made of titanium or silicon carbide and the surrounding parts may be made of stainless steel or plastics material which may be reinforced. A number of hydrocyclone units may be operated in parallel. In an application, the hydrocyclone unit may be used to remove solid impurities from pressure sealing liquid for the shaft packing of a rotary pump. In one embodiment Fig. 8, the delivery pipe of a rotary pump 42 handling crude oil is connected via a conduit 43 and a normally open control valve 44 to a multiplecyclone unit 45. The clean overflow from the cyclone is fed via a conduit 46 to the packing P of the pump while the underflow containing the removed impurities is discharged via a normally open valve 50 and a conduit 49 to the feed inlet pipe 51 of the pump. A differential pressure gauge 52 indicates the extent to which coarse particles build up on the screen member of the unit. When the screen member is clogged, backwashing is effected by closing valves 44, 50 and feeding the crude oil via a conduit 53 in which is inserted a filter 57 and a normally closed valve 54 which is now opened. The oil passes partly to the packing P and partly through the cyclone members and through the screen member from the inside to the outside and is directed with the removed clogging impurities via a conduit 55 and a valve 56, which is normally closed but is now opened, to conduit 49 and the inlet pipe (51). A check valve 46a is provided in the line 46 to prevent back flow from the pump to the seal. In another embodiment, Fig. 9 (not shown), an auxiliary hydrocyclone (59) is inserted in the supply line (62, 65a) for the multiple hydrocyclone unit (58) for removing coarse particles in the oil before its passage to the screen member in the unit (58). The underflow from the hydrocyclone (59) is also discharged into the inlet pipe of the pump.