Revolving extractor

Revolving extractor, countercurrent gravity percolation extractor, solvent-proof body with slowly rotating vanes (rotating individual extraction sections). The rotary-vane passes the continuously fed conditioned solids from the feed shaft over a fixed sieve tray in one rotation to the solids discharge shaft. Sieve tray slots are concentric and expanded at the bottom. At the same time solvent is trickled over the solids. Solvent percolates through the solids and the sieve tray and collected in underneath extract chambers. Countercurrent flow of solids and solvent. 

Depending on the efficiency revolving extractors may be operated in single or multiple units mounted on top of each other, single or multiple solids passes. Throughput 2-2000 tons/d solids. 

In another extractor (Automatic Machinery and Electronics Inc. (AMC)) the individual fmits are cut in half as they pass a stationary knife. The halves are oriented in a vertical plane, picked up by synthetic mbber cups, and positioned across plastic serrated reamers revolving in a synchronized carrier in a vertical plane. As the fmit halves progress around the extractor turntable, the rotating reamers exert increasing pressure and express the juice. The oil and pulp contents in the juice increase with greater reaming pressure. The recoverable oil is removed in a separate step prior to juice extraction. Needle-sharp spikes prick the peel of the whole fmit, releasing oil that is washed away with water and recovered from the oil—water emulsion. 

De Laval Extractor (Palmqvist and Beskow, U.S. Patent 3,108,953, 1959) This machine contains a number of perforated cylinders revolving about a vertical shaft. The liquids folfow a spiral path about 25 m (82 ft) long, in countercurrent fashion radially, and mix when passing through me perforations. There are no published performance data. 

Fig. 34.15. Reflex "basket or circular type" 10,000 ton/day extractor. Note Basket revolves within shell. (Courtesy of Desmet Ballestra Oils and Fats, Brussels, Belgium.)...

The Luwesta (Centriwesta) extractor is a development from Coutor [Eisenlohr, Ind. Chem., 27, p. 271 (1951)]. This centrifuge revolves about a vertical axis and contains three actual stages. It operates at 3800 rotations per minute and handles approximately 5 mVh (1300 gal/h) total liquid flow at 12-kW power requirement. Provision is made in the machine for the accumulation of solids separated from the liquids, for periodic removal. It is used, more extensively in Europe than in tlie United States, for the extraction of acetic acid, pharmaceuticals, and similar products. 

Foremost among mechanical appliances for tjiis purpose ranks the centrifugal machine, or hydro extractor. In principle. this apparatus consists of an upright drum, which can be made to revolve with great velocity on a vertical axle. Tlie drum may hove its sides constructed of sheet metal, perforated with a multitude... 

In opening the piece after firing, the breech-block strikes the lamp on top of the extractor, and revolves it so os to carry the now empty cartrid -shell to the rear. After psssiug a certain ixiint, the >iral spring in front 6f the extractor is released, and accelerates its motion, so that the cartridge is thrown sharply a nst the beveled surface of the ejector-stud, by mch it is deflected upward and exiled from the gun,... 

A similar principle is used in the rotating disc extractor. Fig. 4.14. In this case the vessel diameter is much greater and a comparatively narrow vertical rotor is fitted with horizontal discs at intervals of a few inches. Annular discs are also attached to the internal vertical wall of the stator, opposite the spaces between the rotor discs. The rotor revolves at fairly high speeds and so increases the path lengths of the two phases that theoretical stage... 

The Limesta extractor [14] and the Rotabel [3], extractors revolving about vertical shaft, are used more extensively in Europe than in the United States. 

Hardly any batch-type oilseed extractors remain, and modern solvent extractors mainly are of two basic designs. In shallow bed-type extractors, a 0.5- to 1-meter-thick layer of collets or flakes is pulled across a linear screen (Fig. 8.6), or conveyed on a woven belt, and repeatedly percolated with solvent. Deep bed extractors mainly are constructed as carousels with pie-shaped cells (baskets), that are alternately filled (2-3 meters deep), extracted, and unloaded. In some designs, the baskets rotate between the loading, extraction, drainage, and unloading stations (Fig. 8.7) in others, the baskets are stationary with the various stations revolving (Fig. 8.8). Solvent flow always is countercurrent to the direction of... 

Fig. 8.8. Cutaway drawing of French Stationary Basket Extractor. The deepbed baskets are stationary while the collet/flake loading, extraction, drainage, and unloading stations revolve. By permission of French OH Machinery Co., Piqua, OH.)...

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