Separation equipment sedimenting centrifuge

The degree of cell separation is an important parameter to be evaluated in perfusion systems. This can be done through the use of some concepts as cell separation efficiency, grade efficiency, and cut size. These concepts are applicable to any equipment whose performance remains constant if the operational conditions do not change. They are valid, therefore, for equipment such as sedimenting centrifuges, hydrocyclones, gravitational settlers, etc. 

The relative suitability of the common kinds of solid-liquid separation equipment is summarized in Table 11.3. Filtration is the most frequently used operation, but sedimentation as a method of pretreatment and centrifugation for difficulty filterable materials has many applications. Table 11.15 gives more detail about the kinds of filters appropriate to particular services. 

Sedimenting centrifuges Filtering centrifuges Hydrocyclones Deep-bed filters Cartridge filters Pressure vessel filters Filter presses Continuous filters Gravity separation equipment... 

Centrifugation is a mechanical separation technique, which accelerates the phenomenon of sedimentation through the imposition of rotational motion in a liquid/particle suspension. In the centrifugation equipment, the centrifugal force causes the particles to move radially away from the axis of rotation, as shown in Figure 2.6. 

Leung W.W.F., 2005. Sedimenting centrifuges, in Solid/Liquid Separation Scale-up of Industrial Equipment , Eds. RJ. Wakeman and E.S. Tarleton, pp. 375-441, Elsevier, Oxford. 

Gravity sedimentation equipment, hydrocyclones, sedimenting centrifuges or flotation cells have also been extensively used in mineral processing for separation of minerals according to density or affinity to water. In such separations, the efficiency is expressed by the Tromp curve which, similar to the grade efficiency curve, shows probability of separation as a function of material density or mineral composition. The steepness of the curve is a measure of the sharpness of the separation. 

Water is the most commonly used liquid in industry and in all human activities. Thus most liquid-solids separation equipment is specifically designed for treating aqueous systems. In water suspensions, the sizes of solid partieles are usually very small (in the micron and submicron size range) and surface-active forces often play an important role. Representative examples are the mineral slurries, lyophilie eolloids, slimes, and wastewater mixtures. The treatment of aqueous systems involves four stages floeeulation (elarification), sedimentation (settling), consolidation (compression or compaction), and phase separation (filtration or centrifugation). 

Sedimentation Equipment. Centrifugal sedimentation equipment is usually characterized by limiting flow rates and theoretical settling capabihties. Feed rates in industrial appHcations may be dictated by Hquid handling capacities, separating capacities, or physical characteristics of the soHds. Sedimentation equipment performance is illustrated in Figure 8 on the basis of nominal clarified effluent flow rates and the appHcable values. The... 

These operations may sometimes be better kno Ti as mist entrainment, decantation, dust collection, filtration, centrifugation, sedimentation, screening, classification, scrubbing, etc. They often involve handling relatively large quantities of one phase in order to collect or separate the other. Therefore the size of the equipment may become very large. For the sake of space and cost it is important that the equipment be specified and rated to Operate as efficiently as possible [9]. This subject will be limited here to the removal or separation of liquid or solid particles from a vapor or gas carrier stream (1. and 3. above) or separation of solid particles from a liquid (item 4j. Reference [56] is a helpful review. 

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