Patent GB-1465833-A (GB)
Title: Centrifugal separator
IPC: B01D45/12
Filed: 1974-02-06
Abstract: 1465833 Centrifugal separators PERRY EQUIPMENT CORP 6 Feb 1974 [7 Dec 1973] 05399/74 Heading B2P A separator for removing from a gas stream heavier components present in the gas stream comprises a gas stream inlet conduit 23, Fig. 1, means 41 located in the inlet conduit for imparting a swirling motion to the gas stream, a separation conduit 25 coaxial with the conduit 23, the downstream end 23A, Fig. 2, of the conduit 23 being coaxially located within the upstream end 25A of the conduit 25 and defining therewith an annular injection orifice 43 for the entry of recirculation gas, conduit means 27, 31 coaxial with the conduits 23, 25 and having an upstream end 27A coaxially located within the downstream end 25B of the separation conduit 25 and defining therewith an annular ejection port 45 for the removal of the heavier components from the gas stream, the conduit means including a downstream end 31B for the passage of gas separated from the heavier components. The separator may be in the form of a single- or multistage assembly. Figs. 1 and 2 show a two stage gas-liquid separator comprising an inlet conduit 23, first- and second-stage separation conduits 25, 27 and a gas outlet conduit 31, the conduits being connected together by spacers 51, 53, 55. The separator is mounted in a housing chamber 33 with the inlet and outlet conduits projecting from the chamber. The chamber is supported on a structure 49 and communicates with a liquid reservoir 33A having a drain 33A'. The swirl means 41 consist of two or more semi-elliptical, Fig. 4 (not shown) baffle plates 61, 63 inserted within slots formed in the conduit 23 and arranged at an angle α to the longitudinal axis of the conduit. The ejection port 45 is frusto-conical in cross-section and is bounded by surfaces 25c, 27c, Fig. 5, which flare outwardly in the downstream direction at different angles ° and # relative to the longitudinal axis of the separator. In operation, most of the liquid and other heavier components and a small amount of gas pass through the port 45 into the chamber 33 while the rest of the liquid and other heavier components are ejected with a greater amount of gas through the port 47. The gas entering the chamber 33 is recirculated through the port 43 by the induction effect created by the ejec-  tion action produced by the gas stream discharging from the inlet conduit 23. A num-  ber of separators may be mounted in a chamber 35, Fig. 3 formed between plates 71 and 73 and located in the downstream end of a container 75 having an inlet 79, an outlet 81 and a chamber 77 forming a preliminary separator of the settling type. Liquid is discharged separately from the chambers 77 and 35 through conduits 87 and 91, 93 into separate compartments 83, 85 having drains 89, 95. The separators may also be mounted vertically or at another angle to the horizontal. Examples of liquids and of gases from which they may be separated are given. The separator may also be used for removing solids from dry gases by first injecting a liquid contacting agent to wet the solids through the inlet conduit. The liquid may also act as scrubbing fluid for separation of unwanted gases from the gas stream. For example, a solution of sodium carbonate may be used for the removal of fly ash and sulphur dioxide from flue gases, or diethylene glycol may be injected into the gas stream for the concurrent removal of solids and liquids, as well as for the partial removal of water vapour. The diethylene glycol may be recirculated after reboiling to remove water and after filtration for the removal of solids. Dimensions of the separator are given.