Vane impingement separators

Vane impingement separator elements consist of parallel zig-zag plates or vanes with included collection pockets, simiiar to those shown in Figure 14-2. As an entrainment laden gas moves through the separator, the liquid particles are forced onto the vane surfaces by the inertial impaction mechanism. The resultant liquid film flows to the collection pockets, where it drains by gravity. 

Vane impingement separators are generally purchased from the vendor on a performance basis. Sizes will vary somewhat from one manufacturer to another consequently, the exact size cannot be determined before selection of the manufacturer. The pressure drop across vane impingement separators is approximately 0.25 psi plus 1.5 velocity heads based on the nozzle velocity. The total pressure drop will usually be less than 0.5 psi. 

Impingement separators, 246, 257 Chevron style, 248, 255 Efficiencies, 246 Knitted wire mesh, 246 York-vane efficiencies, 248 Inertial centrifugal separators, 266, 268 Kinetic energy, pump system, 187 Lamella plate classifiers, 239 Line sizing work sheet, 107... 

Can be combined with secondary vapor-liquid separator such as vane impingement type. 

FIG. 14-110 Typical impingement separators, (a) Jet impactor. (b) Wave plate, (c) Staggered channels. (Blaw-Knox Food 6- Chemical Equipment, Inc.) (d) Vane-type mist extractor. (Maloney-Crawford Tank and Mfg. Co.) (e) Peerless line separator. (Peerless Mfg. Co.) (/) Strong separator. (Strong Carlisle and Hammond.) (g) Karbate line separator. (Union Catbide Corporation) (h) Type E horizontal separator. (Wright-Austin Co.) (0 PL separator. (Ingersoll Rand.) (/) Wire-mesh demister. (Otto H. York Co.)... 

Q In a gas compressor train, moisture must be removed from the gas before the latter goes on to the next stage, d his is done either by scrubbing in a knitted-wire-mesh separator, or with a vane-type separator that takes advantage of impingement, centrifugal force and surface tension. 

Impingement and Coalescence. Impingement separation relies upon the difference in momentum, either between a gas particle and a liquid droplet, or between two liquid droplets. It occurs when liquid-laden gas approaches a coalescing device or target (e.g., wire mesh pad, vane element, or filter cartridge). This coalescing device causes the gas to follow a tortuous path, while the liquid droplets continue in a straighter path as. a result of... 

Vane impingement, wire mesh, centrifugal, and Karbate strut separators are commercial proprietary designs and all compete for similar applications. Performance and cost, however, can vary widely from one type to another. The designer should understand the advantages and disadvantages of each type and the level of separation that each can effect. 

Principle of operation. The vane unit is the heart of the separator (see Fig. S-32). As the gas enters the vane unit, it is divided into many vertical ribbons (A). Each ribbon of gas is subjected to multiple changes of direction (B) as it follows its path through the vanes. This causes a semiturbulence and rolling of the gas against the walls of the vanes (C). The entrained droplets are forced to contact the vane walls where they impinge and adhere to the vane surface (D). This liquid then moves into the vane pockets (E) and out of the gas stream where it is drained by gravity into the liquid reservoir. The collected liquid can then be disposed of as desired. 

It is significant to note that the liquid drainage in the vane-type mist extractor differs from the drainage in other impingement-type mist extractors, in that vane drainage occurs with the liquid out of the gas flow and at a ri t an e to the direction of flow through the separator. 

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