Separation equipment centrifuges

Equipment. Centrifugation equipment that separates by density difference is available in a variety of sizes and types and can be categorized by capacity range and the theoretical settling velocities of the particles normally handled. Centrifuges that separate by filtration produce drained soflds and can be categorized by final moisture, drainage time, G, and physical characteristics of the system, such as particle size and Hquid viscosity. 

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... 

Clear-Hquor advance reduces the quantity of Hquor that must be processed by soHd—Hquid separation equipment (for example, a filter or a centrifuge). The reduction in Hquor flow through the separation equipment may allow use of smaller equipment for a fixed production rate or increased production through fixed equipment. 

The transesterification reactions were conducted in a sealed 250 ml autoclave equipped with a stirrer. The molar ratio of methanol to oil was 12 1, reaction temperature was 200 C-230°C, and the ratio of catalyst to oil was about 2 wt%. Samples were taken out from the reaction mixture and biodiesel portions were separated by centrifuge. 

The condensed reaction mixture is evaporated in film evaporator 16 under vacuum. The crude l-(2,6-dimethyl)-phenoxy-2-aminopropane hydrochloride is precipitated in tank 17 using HCl dissolved in organic solvent //, separated in centrifuge 18, and dried in tray drier 19. The final purification by crystallization from solvent III occurs in crystallizer M. Pure l-(2,6-dimethyI)-phenoxy-2-amino-propane hydrochloride is separated in centrifuge 21 and dried in tray drier 22. The plant is equipped with typical solvent recovery and storage facilities not shown in the figures. 

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. 

We report on a number of on-line chemical procedures which were developed for the study of short-lived fission products and products from heavy-ion interactions. These techniques combine gas-jet recoil-transport systems with I) multistage solvent extraction methods using high-speed centrifuges for rapid phase separation and II) thermochromatographic columns. The formation of volatile species between recoil atoms and reactive gases is another alternative. We have also coupled a gas-jet transport system to a mass separator equipped with a hollow cathode- or a high temperature ion source. Typical applications of these methods for studies of short-lived nuclides are described. 

Clear-liquor advance is used for two purposes (1) to reduce the quantity of liquor that must be processed by the solid-liquid separation equipment (e.g., filter or centrifuge) that follows the crystallizer, and (2) to separate the residence time distributions of crystals and liquor. The reduction in liquor flow through the separation equipment can allow the use of smaller equipment for a fixed production rate or increased production through fixed equipment. Separating the residence time distributions of crystals and liquor means that crystals will have an average residence time longer than that of the liquor. This should, in principle, lead to the production of larger crystals, but because the crystallizer is otherwise well mixed, the crystal population density will have the same form as that for the MSMPR crystallizer (Eq. (54)). 

The suspended droplets of liquid monomer are progressively converted to solid or porous PVC particles. Unreacted VCM is stripped from the polymer and water is separated by centrifuging. The polymer is then dried, typically in fluidised bed drying equipment. Prior to start-up of the next polymerisation cycle, the reactor is cleaned and coated with an antifouling agent. The mechanism of action of antifouling agents has been studied (149). 

Any new developments by equipment manufacturers in vegetable oil refining are transferable to rendered fat processing. In-line monitoring of the free fatty acid (FFA) content with automatic addition of the caustic solution followed by mixing and separation by centrifuge has improved refining yields. Some processors have... 

Trowbridge, M. E. O K. (1962) Chem Engr, London, No. 162 (August) 73. Problems in scaling-up of centrifugal separation equipment. 

Timothy C. Frank, Ph.D. Research Scientist and Sr. Technical Leader, The Dow Chemical Company Member, American Institute of Chemical Engineers (Section Editor, Introduction and Overview, Thermodynamic Basis for Liquid-Liquid Extraction, Solvent Screening Methods, Liquid-Liquid Diversion Fundamentals, Process Fundamentals and Basic Calculation Methods, Dual-Solvent Fractional Extraction, Extractor Selection, Packed Columns, Agitated Extraction Columns, Mixer-Settler Equipment, Centrifugal Extractors, Process Control Considerations, Liquid-Liquid Phase Separation Equipment, Emerging Developments)... 

Steady-state control of a continuously fed extraction column requires maintenance of the location of the liquid-liquid interface at one end of the column. The main interface will appear at the top of the column when the light phase is dispersed and at the bottom of the column when the heavy phase is dispersed. If needed, extraction columns can be designed with an expanded-diameter settling zone to facilitate liquid-liquid phase separation by reducing liquid velocities. If sufficient clarification of the phases cannot be achieved, then it may be necessary to add an external device such as a gravity decanter or centrifuge. (See Liquid-Liquid Phase Separation Equipment. ) Sometimes a column is built with expanded ends at... 

---