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Extraction stagewise contact

Contacting Columns. A tall cylindrical column or tower can be filled with packing for continuous contact of two or more phases or fabricated with a number of trays at fixed distances apart for stagewise contact operation. Such columns, either alone or in series, are commonly specified for separations-in gas absorption, distillation, extraction, and humidification. [Pg.117]

Stagewise contact with controlled coalescence redispersion cycles Tray column Pulsed sieve column. Pulsed Mixer-Settler-cascade, Extraction tower with controlled cycle Scheibel column, ARD-Extractor, Leisibach column, Mixer-Settler cascade ... [Pg.426]

Caustic Washing. A flowsheet of the type of Fig. 11.3 may be used, involving stagewise contacting. In the first extractor H2S is removed by a prewash of caustic, as outlined above. The next three stages are used for countercurrent extraction of the mercaptans from the gasoline with aqueous sodium hydroxide, and the treated gasoline is water-washed to remove... [Pg.353]

The archetypal, stagewise extraction device is the mixer-settler. This consists essentially of a well-mixed agitated vessel, in which the two liquid phases are mixed and brought into intimate contact to form a two phase dispersion, which then flows into the settler for the mechanical separation of the two liquid phases by continuous decantation. The settler, in its most basic form, consists of a large empty tank, provided with weirs to allow the separated phases to discharge. The dispersion entering the settler from the mixer forms an emulsion band, from which the dispersed phase droplets coalesce into the two separate liquid phases. The mixer must adequately disperse the two phases, and the hydrodynamic conditions within the mixer are usually such that a close approach to equilibrium is obtained within the mixer. The settler therefore contributes little mass transfer function to the overall extraction device. [Pg.183]

There followed a brief discussion of equipment for carrying out solvent extraction in industrial practice, both by stagewise and differential contact. Some of the first principles for the design of differential contactors were outlined and the part played by the efficiency of extraction in continuous equipment was discussed. Finally there was an outline of methods for the control of solvent loss which forms probably the most important environmental aspect of the application of solvent extraction. [Pg.369]

The transfer of mass from one phase to another is involved in the operations of distillation, absorption, extraction, humidification, adsorption, drying, and crystallization. The principal function of the equipment used for these operations is to permit efficient contact between the phases. Many special types of equipment have been developed that are particularly applicable for use with a given operation, but finite-stage contactors and continuous contactors are the types most commonly encountered. A major part of this chapter, therefore, is devoted to the design aspects and costs of stagewise plate contactors and continuous packed contactors. [Pg.649]

An example describes a specific test. Twenty pounds of pine chips (and we assume they contain their normal moisture of about 50 %) are extracted with 29 pounds of CO2 at 1175 psi and 40 °C. At the end of one minute of contact, the CO2 solution is drawn from the vessel and decreased in pressure stagewise, first to 1,145 psi and 40 °C where 0.24 lb of resin acid precipitates from solution second to 1,115 psi and 38 °C where 0.11 lb of fatty acids precipitate and last to a vessel at 1,085 psi and 34 °C where 0.037 lb of turpentine collects. [Pg.439]

The transfer of mass as well as heat from one material phase to another is quite commonly encountered in chemical process flow sheets. The same physical laws, rate equations, and design principles can be applied to mass-transfer operations as occurring in absorption, adsorption, crystal-lization, distillation, drying, extraction, jluidization, and humidification Equipment is designed to obtain intimate contact between phases, in either a stagewise or continuous manner, and many special types of equipment have been developed for any given operation. This discussion will be limited to the conventional types of equipment. [Pg.117]

Consider the countercurrent extraction of solute A from solution in B using pure solvent C. The operatioo is performed in the column shown in Fig. 7.3-1, which may be either continuous-contact (packed) or stagewise. [Pg.420]


See other pages where Extraction stagewise contact is mentioned: [Pg.89]    [Pg.167]    [Pg.129]    [Pg.159]    [Pg.427]    [Pg.424]    [Pg.427]    [Pg.368]    [Pg.371]    [Pg.728]    [Pg.477]    [Pg.427]    [Pg.542]    [Pg.130]    [Pg.721]    [Pg.1199]    [Pg.359]    [Pg.43]    [Pg.242]    [Pg.555]    [Pg.67]    [Pg.496]    [Pg.4]    [Pg.20]    [Pg.496]    [Pg.849]    [Pg.585]    [Pg.496]   
See also in sourсe #XX -- [ Pg.427 , Pg.490 ]

See also in sourсe #XX -- [ Pg.427 , Pg.490 ]

See also in sourсe #XX -- [ Pg.427 , Pg.490 ]




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