Large batch centrifugation

Solids-retaining separators (Fig. 2) are batch centrifuges. They are generally larger in diameter than tubular bowls. Therefore, they are large enough to contain a disk stack but are dependent on at least partial disassembly for manual removal of solids. The larger... 

On the completion of nitration the batch is dropped from the reaction vessel into a centrifuge and the acid mixture spun off and recovered. The nitrated linters, which still contain appreciable quantities of acid, are then plunged into a drowning tank, where the nitric acid is diluted with a large volume of water. The resultant ester is then pumped, as a slurry, into storage vats which may hold the products of several nitrations. 

Extraction Frozen krill (85 g) is briefly homogenized with 60% ethanol (220 ml) at about 0°C, and centrifuged. The supernatant is rapidly concentrated under reduced pressure in a 2-liter flask at about 40°C (using a rotary evaporator, a mechanical vacuum pump, and a large condensate trap immersed in dry ice/acetone) to a volume of 15-20 ml. After the addition of 30 ml of cold ethanol, the solution is temporarily stored at —30°C. Materials similarly prepared from 6 batches (510 g krill in total) are combined, centrifuged, and the supernatant is concentrated to 30 ml, and then mixed with 70 ml of ethanol. Compound F in the solution is extracted with 120 ml of n-butanol. 

Results for Commercial Operations The content of a-form was up to 99% and average size of the crystal was about 24-35 jum. The formation of 3-form crystal In commercial operation Induced considerable Increase of the viscosity of the suspension. The features of the semi-batch cooling crystallization process are as follows. Even if crystallization temperature is considerably lowered in order to avoid the formation of 3-form crystal, and also even if the feed solution is highly concentrated at high temperature above -SSSK, obtained crystal size is large enough to separate the solvent by centrifuge. 

Mix the protein dissolved in binding buffer with equilibrated lEC gel. Agitate for several minutes and separate gel and solution either by centrifugation or filtration. Wash and elute the gel on a funnel or in a column. Since the equilibrium is established only once, a nearly complete absorption occurs if the gel is in a large excess. The advantage of batch loading is the easy separation of gel and liquid. 

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