Hydrocyclones applications

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,... 

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. 

The nomographs by Zanker can be used to make a preliminary estimate of the size of cyclone needed. The specialist manufacturers of hydrocyclone equipment should be consulted to determine the best arrangements and design for a particular application. 

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

Svarovsky, L. and Thew, M. T. (1992) Hydrocyclones Analysis and Applications (Kluwer). 

In this section, the general design of the hydrocyclone and its application in the grading of solid particles, or their separation from a liquid, is considered and then the special features required in hydrocyclones required for the separation of immiscible liquids will be addressed. The use of cyclones for separating suspended particles from gases is discussed in Section 1.6.2. 

Trawinski, H. F. In Hydrocyclones Conference Cambridge, U.K. (1980), BHRA Fluid Engineering 179. The application of hydrocyclones as versatile separators in chemical and mineral industries. 

There is a clear need for other size classifiers which combine a high separation efficiency with flexibility and compactness. Hydrocyclones have a small volume, are simple in operation and are standard size classification equipment, for example in closed circuit grinding applications. The recent development of the flat-bottom hydrocyclone, which permits classification in the coarse size range, creates an additional motive to study the use of hydrocyclones for Crystal Size Distribution (CSD) control. Furthermore, throttling of a flat botom hydrocyclone does not necessarily provoke blockage but allows continuous control of its cut size when a controlled throttling valve is used. There is a clear incentive for its use in this application since it may provide an additional process input. 

The disadvantage of the annular zone is its large volume, which is. 6 m in this application as opposed to 0.003 for the hydrocyclone. If, size clcussiflcation is to be applied in a batch crystallisation operation this might be a serious disadvantage. Furthermore, a hydrocyclone is more easily exchanged if a change in cut size is required. 

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. 

Hydrocyclones can be easily designed to promote a desired separation [45], and their performance can be easily predicted [31]. It is worth mentioning that Eqs. (1) to (6) are also applicable to hydrocyclones. 

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-... 

In Hydrocyclones A Solution to Produced Water Treatment, Meldrum presents the basic design principle of a dc-oilmg hydrocy leone. System design, early operational experiences, and test results on a full-scale application in the North Sea are discussed. Oil-removal efficiency was seen to rise with increasing reject ratio up to around 1%, producing acceptable outlet concentrations Early field test results on a tension leg platform in the North Sea are discussed. Preliminary data on a pumped system are also given. 

Our first experience with hydrocyclones was with pilot plant trials of the Serck-Baker Oilspin developed as a result of an extensive research program conducted at Southampton U. J While these tests, carried out oo the Murchison and Hutton platforms in early 1983, were not an unqualified success, they demonstrated the equipment s potential and enough encouragement for us to commit to die first Mi-scale commercial application of the Vortoil four-t in-one 35-nun (l.4-in. hydrocyclone later that year. 

To gain universal acceptance in the oil industry, it will be necessary to develop an acceptable combination of pumps and hydrocyclones to cover the many potential low-pressure applications. All research time spent in this area will have a significant impact on the hydrocyclone s market potential. 

A direct application to chemical process technology of the principle of electric wind is in electrostatic precipitators (Leonard et al.,1983) and electrocyclones for size separation of particles in powder technology (Nenu et al., 2009). Electrostatic precipitators applied to exhaust gas cleaning have recently been reviewed 0aworek et al., 2007). A particularly interesting development is that of a small electrocyclone with a diameter of 75 mm (Shrimpton and Crane, 2001). With this device it was shown that the separation quality of the smallest size particles with a diameter below 38 pm doubled upon application of the electric wind. Later experiments performed with submicron silica particles demonstrated that classification of such particles is possible by use of an electrical hydrocyclone (Nenu et al., 2009). 

The hydrocyclone process is applicable for processing hard and soft wheat flours, and perhaps even wholemeal flour.92 In addition to its versatility in processing different wheat classes, other advantages of the hydrocyclone process compared to the Martin process include an increased yield of gluten, lower water and energy requirements, and manageable levels of effluent. To ensure the food safety of wheat starch, quality programs in many companies dictate the implementation of hazard analysis and critical control points in the hydrocyclone process.24... 

In studies that involve the CFD analysis of turbulent fluid flow, the k-t model is most frequently used because it offers the best compromise between width of application and computational economy (Launder, 1991). Despite its widespread popularity the k-e model, if used to generate an isotropic turbulent viscosity, is inappropriate for simulation of turbulent swirling flows as encountered in process equipment such as cyclones and hydrocyclones (Hargreaves and Silvester, 1990) and more advanced turbulence models such as the ASM or the RSM should be considered. Because these models are computationally much more demanding and involve an increased number of empirical parameters compared to the k-e model, other strategies have been worked out (Boysan et al, 1982 Hargreaves and Silvester, 1990) to avoid the isotropic nature of the classical k-e model. 

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