Plate agitator

Masiuk S., Mixing time for a reciprocating perforated plate agitator, Inz. Chem. Proc. (Polen) 20 (1999), p. 601-612... 

Changing Continuous Air distributor plate, agitator— impeller, blade chopper, distributor plate, filter socks, nozzle. 

FLOW GENERATED BY A PLATE AGITATOR, 459 Flows in Vertical Planes, 459 Flows in Horizontal Planes, 460 Discussion, 460... 

Anne-Archard has made the assumption that, in the case of a vessel with a plate agitator, the flow was two-dimensional far from both the bottom and the top of the tank, and has considered the case of a fluid with a rheological behavior well correlated by the model of Oldroyd B [14). In the laminar flow regime (Re = 5), streamlines are given in Figure 10 in the case of a purely Newtonian fluid (De = 0)... 

In the case of viscoefastic fluids, the modeling of hydrodynamic in agitated tanks remains difficult, but Anne-Archard has given preliminary results in the case of a plate agitator [14]. In the laminar flow range, it appears that the effect of elasticity... 

In the case of a packed column, the terms on the right-hand side should each be divided by the voidage, ie, the volume fraction not occupied by the soHd packing (71). In unpacked columns at low values of the sHp velocity approximates the terminal velocity of an isolated drop, but the sHp velocity decreases with holdup and may also be affected by column internals such as agitators, baffle plates, etc. The sHp velocity can generally be represented by (73) ... 

Fig. 15. Mechanically agitated columns (a) Scheibel column (b) rotating-disk contactor (RDC) (c) asymmetric rotating-disk (ARD) contactor (d) Oldshue-Rushton multiple-mixer column (e) Kuhni column and (f) reciprocating-plate column.

Convective heat transfer is classified as forced convection and natural (or free) convection. The former results from the forced flow of fluid caused by an external means such as a pump, fan, blower, agitator, mixer, etc. In the natural convection, flow is caused by density difference resulting from a temperature gradient within the fluid. An example of the principle of natural convection is illustrated by a heated vertical plate in quiescent air. 

Paste Mixing. The active materials for both positive and negative plates are made from the identical base materials. Lead oxide, fibers, water, and a dilute solution of sulfuric acid are combined in an agitated batch mixer or reactor to form a pastelike mixture of lead sulfates, the normal, tribasic, and tetrabasic sulfates, plus PbO, water, and free lead. The positive and negative pastes differ only in additives to the base mixture. Organic expanders, barium sulfate [7727-43-7] BaSO carbon, and occasionally mineral oil are added to the negative paste. Red lead [1314-41 -6] or minium, Pb O, is sometimes added to the positive mix. The paste for both electrodes is characterized by cube weight or density, penetration, and raw plate density. 

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