Raining bucket

FIG. 23"37 Equipment for liquid/liquid reactions, a) Batch stirred sulfonator. (h) Raining bucket (RTL S A, London), (c) Spray tower with Loth phases dispersed. (d) Two-section packed tower with light phase dispersed, (e) Sieve tray tower with light phase dispersed, (f ) Rotating disk contactor (RDC) (Escher B V, Holland). (g) Oldshue-Rushton extractor (Mixing Equipment Co. ). 

Figure 14.15. A horizontal rotating extractor and two kinds of centrifugal extractors, (a) The RTL (formerly Graesser raining bucket) horizontal rotating extractor both phases are dispersed at some portion of the rotation RTL S. A., London). (b) Operating principle of the Podbielniak centrifugal extractor it is made up of several concentric perforated cylinders (Baker-Perkins Co.), (c) The Luwesta centrifugal extractor (schematic diagram) Luwa Corp.).

Kuhni column Graesser raining-bucket contactor... 

The RTL contactor, formerly known as the Graesser raining bucket contractor (Fig. 14), is a horizontal design with the phases interdispersed by water wheel arrangements. The unit has the unusual feature of dispersing each phase into the other. The contactor was developed for... 

FIGURE 14 Graesser raining-bucket contactor. [Reprinted by permission of Chem. Eng. 75(18), 76 (1968).]... 

The panels were exposed at 30 between ceramic insulators facing south at the site (2). Panels of each metal were exposed in triplicate for periods of 6, 12, and 24 months. The six-month panels were continually replaced with cleaned panels in order to study the corrosion during winter and summer exposures. Two sets of each metal panels were exposed at the site. An automatic device which is triggered by a sensor on a rain bucket collector covered one set of panels only during each rain event. This set of panels is exposed primarily to dry deposition. The remaining set of panels was exposed uncovered to wet and dry deposition. After each exposure period the panels were removed, then cleaned according to the procedure established prior to the exposure and reweighed to 0.1 mg. 

Mechanical rotation Mixer-Settler RDC Oldshue-Rushton Column ARD Column Ktkhni Column Raining Bucket Contactor... 

Raining Bucket Contactor. This contactor consists of a series of scoops located on a slowly rotating, baffled rotor within a horizontal cylindrical vessel (Fig. 21). An interface is maintained near the middle, and the scoops capture and then allow one phase to rain through the other, and vice versa, once each revolution. 

There is little, if any, control of droplet size, but the raining bucket contactor is the only one that disperses each phase in the other. If the flow ratio differs greatly from unity, backmixing of the low flow phase can be serious, and line out with changed operating conditions can take a long time. 

Proprietary Extractors. Manufacturers or proprietary design extraction equipment (such as the Podbielniak Centrifugal Extractor or the RTL (raining bucket) Contactor) provide catalogs listing the relative capacities of the various sizes of equipment which are offered. Pilot equipment is usually available for determining extraction performance, and the manufacturer utilizes both the pilot data and experience with similar systems to provide assured commercial designs. 

Gravity flow (raining bucket, RTL) product of the density difference with the interfacial tension (Mg/m, mN/m) >1 and number of theoretical stages needed <3 handles dirty liquids and ones that tend to emulsify. 

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