Baffle divider

Propeller Yes No limitation 0.54 (Npe) - (Np,) --5 45 pitched, four-blade impeller. Fquation is based on limited data with regard to propeller pitch and vessel baffling. Divide hj obtained with this equation by a factor of about 1.3. 

Fig. 9.8 Sections of several stirred countercurrent columns. Horizontal stator baffles divide the column into successive sections, each fitted with a mixer, aU fixed to a central shaft. The mixers disperse one phase into droplets and mix the two phases in the section as efficiently as possible. The stator baffles must support the phase separation and the countercurrent flow of the liquids from state to stage.

A vertical wall, called reactor baffle, divides the primary pool into hot and cold pools. The large thermal inertia provided by the large pool enhances the plant safety. The IHTS consists of two loops and each loop has its own steam generator and related systems. 

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) ... 

A numerical study of the effect of area ratio on the flow distribution in parallel flow manifolds used in a Hquid cooling module for electronic packaging demonstrate the useflilness of such a computational fluid dynamic code. The manifolds have rectangular headers and channels divided with thin baffles, as shown in Figure 12. Because the flow is laminar in small heat exchangers designed for electronic packaging or biochemical process, the inlet Reynolds numbers of 5, 50, and 250 were used for three different area ratio cases, ie, AR = 4, 8, and 16. 

G is a split flow. The fluid comes in and goes both way.s around the longitudinal baffle and then exits. H is very rare a double split flow. J is a divided flow. K is a kettle type reboiler, which is a special type and is best explained by looking at the example AKT in Figure 3-9. Kettle types are common where there is a boiling liquid or where gas is liberated from shell fluid as it is heated. The weir controls the liquid, making sure the tubes are always immersed in liquid. Gas that flashes from the liquid can exit the top nozzle. 

The layout of the heat exchanger tubesheet determines the number of tubes of a selected size and pitch that will fit into a given diameter of shell. The number of tubes that will fit the shell varies depending upon the number of tube-side passes and even upon whether there is a shell-side pass baffle that divides the shell itself into two or more parts. 

Methods of dust removal depend mainly on the particle size of the dust and the temperature and moisture content of the gas. The methods used are broadly divided into dry methods and wet methods. The dry methods involve the use of gravity and baffle chambers, cyclones, filters, and electrostatic precipitators, while the wet methods involve the use of spray towers and venturi scrubbers. In principle, wet cleaning is preferred to dry cleaning because of the excessive wear associated with and the difficulty in handling the fine dusty material removed in the dry methods. The wet methods, however, must be followed by such operations as filtration, drying of filter cakes, and recycling of water. 

Figure 12.12. Shell types (pass arrangements), (a) One-pass shell (E shell) (b) Split flow (G shell) (c) Divided flow (J shell) (d) Two-pass shell with longitudinal baffle (F shell) (e) Double split flow (H shell)...

Use 25 per cent cut baffles, baffle arrangement for divided shell as shown below ... 

A reactor with a number of dividing baffles is to be used to run the reaction... 

Very large beaters (capacity 25 m3), may be used (Figs. 155 and 156). Here, the cutting drum is situated at one end of the tub which is made either of cast iron, from a couple of units to be assembled together, or of concrete. Concrete vessel are lined internally with glazed tiles. The trough is divided into two by means of a vertical baffle plate. In these compartments the bottom is inclined in opposite directions in order to facilitate the circulation of the pulp. 

Regions of stagnancy are often caused by baffles and by interference due to pipes and fittings in corners and other places where abrupt changes in flow paths can occur. It is evidenced principally by long tails in the residence time distribution curve and in extreme cases, by a mean residence time which is very much shorter than that calculated by the volume divided by the flow rate. 

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