Centrifuge equipment batch filtering centrifuges

Centrifuge Dryers Usually they are batch or continuous filtering centrifuges (Sec. 18, "Liquid-Solid Operations and Equipment ) with hot air being blown over the solids in the discharge section. Manufacturers include Heinkel and Bird-Humboldt. 

Another piece of equipment that has been used to manufacture pellets by solution/suspension layering is the tangential spray or centrifugal granulator. An important parameter that needs to be established early in the process is quantity of starter seeds or cores charged into the machine that should, at the minimum, cover the nozzles during start-up otherwise, the sprayed liquid droplets will either be sprayed onto the wall of the product container or become entrained in the fluidization air. The latter could lead to clogging of the filters, which would then not only increase the pressure differential across the filters and compromise the batch but also may complicate equipment cleanup. In either case, the yield, and probably the quality of the pellets, will be reduced dramatically. As the size of the... 

The ability to separate a mixture of two liquid phases is critical to the successful operatiou of mauy chemical aud petrochemical processes. Besides its obvious importauce to liquid-liquid extractiou aud washing operations, liquid-liquid phase separation can be a critical factor in other operations including two-liquid-phase reaction, azeotropic distillation, and industrial wastewater treatment. Sometimes the required phase separation can be accomplished within the main process equipment, such as in using an extraction column or a batch-wise, stirred-tank reactor but in many cases a stand-alone separator is used. These include many types of gravity decanters, filter-type coalescers, coalescers filled with granular media, centrifuges, and hydrocyclones. 

The simplest type of extraction equipment is the stirred tank, coupled with a solid-liquid separation step such as a screen, filter, or centrifuge to separate the marc from the extract. This equipment is readily available in a wide variety of sizes and can be operated as a single-batch extractor or run in series in a countercurrent mode as shown in Figure 11.6. 

For a particulate application involving SLS, how to choose the best equipment, to use batch or continuous operation, which filter medium to select, and what is the optimum operating conditions are concerns of engineers. Although theories are available for some SLS operations, solutions for equipment selection, process design, and optimization are still very much dependent on test and experience, and are frequently qualitative or semi-qualitative. In this section, strategy and decision networks for selection of SLS equipment, introduction of filter media, centrifugal pumps for filtration operation, and selection of filter aids by cycle analysis will be discussed. 

Catalytic reduction can be carried out in batches in steel or, preferably, in stainless-steel kettles equipped with agitators or in towers packed with a catalyst and equipped for recycling operation. Gas-liquid and liquid-liquid separators are required, as well as filters or centrifuges to remove the catalyst, which may be used as such or deposited on inert carriers. Where necessary, purification is carried out, as by fractionation in columns. 

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