Centrifugal clarifier

In the precoat and body feed mode, filter aids allow appHcation of surface filtration to clarification of Hquids, ie, filtration of very dilute suspensions of less than 0.1% by volume, such as those normally treated by deep bed filters or centrifugal clarifiers. Filter aids are used in this mode with pressure filters. A precoat is first formed by passing a suspension of the filter aid through the filter. This is followed by filtration of the feed Hquid, which may have the filter aid mixed with it as body feed in order to improve the permeabiUty of the resulting cake. The proportion of the filter aid to be added as body feed is of the same order as the amount of contaminant soHds in the feed Hquid this limits the appHcation of such systems to low concentrations. Recovery and regeneration of filter aids from the cakes normally is not practiced except in a few very large installations where it might become economical. 

Knife-Discbarge Centrifugal Clarifiers Knife-discharge centrifuges with solid instead of perforated bowls are used as sedimenting... 

The latter requires that the starting product solution be centrifuged, clarified, and at times, dialyzed, before it can be adsorbed on a packed column. In contrast, capturing the desired product by the expanded-bed method is simpler because the crude starting solution is pumped directly on the adsorbent. 

Knife-Discharge Centrifugal Clarifiers Knife-discharge centrifuges with solid instead of perforated bowls are used as sedimenting centrifuges. The liquid flow is usually continuous until the settled solids start to interfere with the effluent hquid. The feed enters the... 

The Podbielniak and Alfa Laval centrifugal extractors are essentially continuous differential contactors. The Westfalia and Robatel centrifugal extractors contain discrete mechanical stages, and flow from one to another is effected by spill over discs and skimmers according to usual centrifugal clarifier practice. As the number of discrete stages is increased, the allowable flow rates are proportionately decreased. 

Centrifugal clarifier n. Apparatus somewhat similar to a cream separator, used for clarifying clear and colored solutions by throwing out solid particles by means of centrifugal force. Clarifiers of this type are operated at high speed. The bulky and apparently undissolved particles are thrown aside into a collector. 

Hemfort, H. and Kohlstette, W. (1984). Centrifugal clarifiers and decanters for biotechnology. Technical Scientific Documentation Number 5, Westfalia Separator AG, Oelde, Germany. 

Schematic diagram of radial separation zones in the cross section of a centrifugal clarifier.

Calculate the capacity of a centrifugal clarifier separating particles 2 pm in size and higher. The clarifier is 2 in diameter and 9 in height. The particles are suspended in water, have a density of 1620 kg/m, and form a layer on the centrifuge wall 0.1 in thick. The rotational speed of the centrifuge is 15,000 rpm. 

Adsorption isotherms for three molecular weight fractions of oligomer salt are presented in Figure 2. The experimental method is to analyze the centrifugally clarified serum from a latex of known interfacial area and total oligomer content. Adsorption is calculated by difference between total and dissolved oligomer at equilibrium. 

Sigma has units of area, which is consistent with non-centrifugal clarifying... 

Centrifugal clarifiers are intended to clean oil free of suspended solids and so have no separate water outlet holes. Feed is from the outer edge of the disc stack, into the zone of maximum centrifugal force, with sludge separating outwards to the bowl wall. 

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