Basket centrifuges

Fixed-Bed Centrifuges. The simplest of the fixed-bed centrifuges is the perforated basket centrifuge (Fig. 31) which has a vertical axis, a closed bottom, and a Hp or overflow dam at the top end. Some domestic machines of this type are ia use for straining vegetable or fmit juices. Ia the iadustrial versioas, the basket housiag is oftea supported by a three-point suspeasioa called the three-column centrifuge. 

The plough cannot be allowed to reach too close to the cloth and some residual cake remains. Where this is not acceptable, the cake may be removed by a pneumatic system, by vacuum, or by reslurrying. The cycle can be automated and controlled by timers. The maximum speeds of basket centrifuges vary from 800 to 1500 rpm, and basket diameters are in the range from 10 to 1400 mm. A 1200-mm diameter, 750-mm long basket may handle as much as 200 kg of cake in one charge. 

Table 2. Basket Centrifuge Operation on Free- and Slow-Draining Particles...

Variable-speed basket centrifuges rotate on a vertical axis. The cyhndrical perforated basket, connected at one end to a bowl head or hub, is driven from below or suspended from above by a driveshaft. It is capped at the other end with a weir ring. The hub may be a solid piece or with an annular opening. If the hub is a sohd piece, the shiny is introduced into the basket at low speed despite the fact that the earths gravity may influence the annular pool. The settled sohds can be removed from the top only when the machine is at rest. Otherwise,... 

Solid-Bottom Basket Centrifuges SmaUer-scale, solid-bottom batch basket centrifuges are available for small test samples, when the sample cannot tolerate mechanical handling or when the traces of solids remaining in a more automated centrifuge would be subject to decomposition or spoilage. 

Link-Suspended Basket Centrifuges In centrifuges with diameters larger than 762 mm (30 in), the basket, curb, curb cover, and drive form a rigid assembly flexibly suspended from three fixed posts (also known as a three-column centrifuge). The three suspension members may be either chain hnks or stiff rods in ball-and-socket joints and are spring-loaded. The suspended assembly has restrained freedom to oscillate to compensate for a normal out-of-balance condition. The drive is vertical with more efficient power transmission compared to the base-bearing type. 

Pressurized Siphon Basket Centrifuges In addition to a siphoning action downstream of the filter, an additional pressure difference of as much as 5 to 6 atm is imposed across the filter to further... 

The oil thus obtained, which should amount to 1460-1600 cc., is dissolved in three times its volume of 95 per cent ethyl alcohol and the mixture cooled to —10 to o°, when the erucic acid crystallizes (Note 3). After six to eight hours at this temperature, the crude erucic acid is collected on a basket centrifuge (Note 4). The mother liquor, on chilling, yields a second crop of erucic acid. The combined product (800-1100 g.) melts either partially or wholly at room temperature, owing to the presence of oleic acid. It is dissolved in an equal volume of alcohol,... 

A slurry containing a solvent mixture of 90% methylcyclohexane and 10% toluene was being fed into a basket centrifuge. A foreman was about to look into the centrifuge when it exploded. The lid was lifted and a flame was released between the centrifuge and the lid. The foreman s hand was burned. 

Basidiomycetes, reproduction in, 26 452 Basil leaf, 23 164 Basin-type solar still, 26 91 Basket centrifuge, 11 389-390 conical, 11 391 Bast fiber plants, 11 594 Bast fibers, 11 285, 288, 289 as cellulose source, 5 363, 367 mechanical properties of, 11 290-291 processing of, 11 291-295 uses of, ll 299t, 300... 

Perforate basket centrifuges, 16 660 operation, 5 529, 543-545 Perforated bowl centrifuge, theory of performance, 5 515 Perforated-drum dryers, 9 120 Perforated-plate columns, 10 772-774 Perforated plates, 11 810 Performance. See also Filter performance of BJTs, 22 248-249 of FETs, 22 165... 

The final pH of the initial extract from the vibrating screen was 7.5 but this increased to pH 9.6 and 10.2 for fababean and field pea, resp., during the second extraction. The filtrates were combined and centrifuged on a Fletcher basket centrifuge at 3400 rpm (1800 x g) to separate the starch and protein (Figure 2). 

The starch fraction was washed initially with 0.02% NaOH, the extract being added to the protein solution (Figure 2). The starch was then slurried in distilled water, separated by sedimentation, and dried at 30°C. The combined protein extracts were adjusted to pH 4.5 with IN HC1 and the whey separated from the curd by centrifugation in the basket centrifuge (1100 x g). The protein curd was washed twice with water adjusted to pH 4.5, then resuspended at pH 7.0 using IN NaOH. The proteinate was freeze-dried. 

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