Solid-liquid separation hydrocyclones

L., and Thew M. T., (eds.). Hydrocyclones Analysis and Applications, p. 95, Kliiwer Academic Publishers, Dordrecht, The Netherlands, 1992. Dahlstrom D. A., Fundamental of Solid-Liquid Separation, Mnlar A. L., and Anderson,... 

Hydrocyclones are used for solid-liquid separations as well as for solids classification, and liquid-liquid separation. It is a centrifugal device with a stationary wall, the centrifugal force being generated by the liquid motion. The operating principle is basically the same as that... 

Svarovsky L. Hydrocyclones. In L Svarvosky, ed. Solid-Liquid Separation. 3td ed. New York Butterworths, 1990. 

Hydrocyclones were originally designed to promote solid-liquid separations, but nowadays they are also used for solid-solid, liquid-liquid and gas-liquid separations. Possible new applications, such as cell separation, are being devel-... 

The construction of hydrocyclones is very simple and therefore very economical compared to all the other solid/liquid separation equipment. However, low efficiencies in separation is the major disadvantage. 

Chen, W. 2002. Solid/liquid separation fundamentals and practice. AIChE Today Series. New York AIChE. Chen, W. 2004. The Use of Hydrocyclone Models in lYactical Design. 9th World Filtration Congress, New Orleans, LA, April 19-22. 

P pressure gauges RC,RA RCE reactor catholyte, anolyte compartments HA, HC anoljrte, cathol3de heat exchangers FM flow meter S gas/liquid separator C hydrocyclone AM,CM anolyte, catholjde tank ISE ion selective electrode ADDS chemical additions CW cooling water G gas vent D to drain F solid/liquid separator and collection tray PA,PC anolyte, catholyte pumps. 

Although there are several ways in which solid/liquid separation may be achieved (e.g. settling, flotation, hydrocyclones, evaporation, magnetic, electrostatic, gravity, centrifuge, vacuum, and pressure), the mechanisms that consume the largest volume of textile filter media, and on which this section will concentrate, are those of pressure and vacuum. 

A hydrocyclone is a device employing centrifugal separation without the need for mechanically moving parts, other than a punq). They are cheap, conq)act and versatile as a means of solid-liquid separation. It is similar in operation to a centrifuge, but with much larger values of g -force (ranging from 800 g in a 300 mm diameter cyclone to 50 000 g in a 10 mm diameter cyclone). This force is, however, applied over a much... 

A basic appreciation of slurry rheology, or flow behaviour, is in oitant in many solid-liquid separations, e.g. when feeding pressure filters, punq)ing thickener underflow, hydrocyclone feed and exit streams and during cross-flow filtration. This Appendix is designed to introduce some of the terminology and basic concepts. A more thorough text such as Wilkinson [1960] should be referred to for further details, if necessary. 

Kelsall, D. F. 1966. The theory and applications of the hydrocyclone. In Solid-Liquid Separation, Poole, J. B. and Doyle, D. (eds.). London Her Majesty Stationary Office (HMSO). 

Trawinski, H.R 1977. Hydrocyclones. In Solid/Liquid Separation Equipment Scale-up, Purchas, D. B. (ed.). Croydon, UK Uplands Press Ltd. 

Gibson, K., Large scale tests on sedimenting centrifuges and hydrocyclones for mathematical modelling of efficiency Proc. of the Symposium on Solid—Liquid Separation Practice, Yorkshire Branch of the I. Chem. E., Leeds, England, March 27-29 (1979), pp. 1-10... 

Svarovsky, L., Evaluation of small diameter hydrocyclones , LChem.E. Symposium on Solid/Liquids Separation Practice and the Influence of New Techniques, Leeds, 3-5 April 1984, Paper 24,193-205, Inst, of Chemical Engineers, Yorkshire Branch (1984)... 

Bloor, M. I. G., Ingham, D. B. and Ferguson, J. W. J., A viscous model for flow in the hydrocyclone . Session I, Solid-Liquid Separation Practice III, 397th Event of the European Federation of Chemical Engineering (Bradford, 1989)... 

Thirdly, there are those chapters which only needed minor updating and amendments. These include Characterization of Particles Suspended in Liquids, Efficiency of Separation of Particles from Fluids, Hydrocyclones, Separation by Centrifugal Sedimentation, Filtration Fundamentals, Methods for Limiting Cake Growth, Pressure Filtration, Particle-Huid Interaction, Thermodynamics of Solid-Liquid Separation. 

The solid-liquid separation in hydrocyclones is never complete, because there is always liquid discharging with the solids through the underflow. The term separation efficiency used for the hydrocyclone is usually defined for measuring the capability of the hydrocyclone of separating the solids from the feed into the underflow. There are a number of different terms for the separation efficiency used in the literature. They include total efficiency, reduced total efficiency, grade efficiency, reduced grade efficiency, and cut size. 

Cyclones can be used for the classification of solids, as well as for liquid-solid, and liquid-liquid separations. The design and application of liquid cyclones (hydrocyclones) is discussed in Section 10.4.4. A typical unit is shown in Figure 10.3. 

Hydrocyclones are used for some liquid-liquid separations, but are not so effective in this application as in separating solids from liquids. 

Centrifugal force can also be used to separate solid particles from fluids by inducing the fluid to undergo a rotating or spiraling flow pattern in a stationary vessel (e.g., a cyclone) that has no moving parts. Cyclones are widely used to remove small particles from gas streams ( aerocyclones ) and suspended solids from liquid streams ( hydrocyclones ). 

Very fine dispersions can be separated effectively with disk-type centrifuges. Commercial units have capacities of 5-500 gpm and are capable of removing water from hydrocarbons down to the ppm range. A mild centrifugal action is achieved in hydrocyclones. They have been studied for liquid-liquid separation by Sheng, Welker, and Sliepcevich (1974), but their effectiveness was found only modest. The use of hydrocyclones primarily for the recovery of solid particles from liquids is described in the book of Bradley (1965). A symposium on coalescence has papers by Belk (1965), Jordan (1965), Landis (1965), and Waterman (1965). 

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