Spiral ring packing

A further modification of the basic cylindrical shape involves installation of a helix inside the cylinder. The interior of this ring may contain a single, a double, or a triple helix. This spiral ring packing normally is made from ceramic and only should be installed by stacking. 

There are 24 absorption towers, 31 feer 6 inches, by 34 feet 2 inches, by 60 feet high. Although these towers are built of brick they serve the same purpose as, and are very similar to, the absoi ption towers previously described for the arc process plant at Rjukan, Norway. These towers are packed with 6 inch and 3 inch vitrified spiral rings. The acid liquor is raised to the tops of the towers by air lifts in acid wells. There are 120 of these acid wells 12 inches in diameter by 96 feet deep. For weighing the acid there arc twelve aluminum tanks each ii feet in diameter by 10 feet deep equipped with Fairbanks beam scales. There are also 12 closed storage tanks each 31 feet diameter by 10 feet high constructed of reinforced concrete of a total capacity of 3,500 tons of 40 per cent acid. 

Figure 6,29 Regular, or stacked, packings (a) Raschig rings, stacked staggered (top view), (6) double spiral ring (Chemical Processing Products Dioision, Norton Co.), (c) section through expanded-meial-lath packing, (d) wood grids.

Application of Packing Coils and spirals are cut to form closed or nearly closed rings in the stuffing box. Clearance between ends should be sufficient to allow for fitting and possible expansion due to increased temperature or hquid absorption of the packiug while in operation. 

Rubber (straight) To 600 See Gasket Materials for properties. Mainly used for ring-type seals, although some types are available as spiral packings. 

The absorption of reactants (or desorption of products) in trickle-bed operation is a process step identical to that occurring in a packed-bed absorption process unaccompanied by chemical reaction in the liquid phase. The information on mass-transfer rates in such systems that is available in standard texts (N2, S6) is applicable to calculations regarding trickle beds. This information will not be reviewed in this paper, but it should be noted that it has been obtained almost exclusively for the more efficient types of packing material usually employed in absorption columns, such as rings, saddles, and spirals, and that there is an apparent lack of similar information for the particles of the shapes normally used in gas-liquid-particle operations, such as spheres and cylinders. 

Berl saddles, Lessing rings, Nielson propeller packing, Hechenbleikner blocks, Stedmann packing, Bregeat multiple spirals etc. Here, as in the case of plate towers, the liquid flows from the top of the tower and the gas enters at the bottom... 

---