The Nutsche, tipping pan and table filters are intended only for solids recovery from liquid suspensions. The rotary drum filter is mainly used for that purpose, but has some applications in clarification as well as solids recovery. Rotary drum filters may be vacuum driven (rotary drum vacuum filters) or pressurized (pressure drum filters). The former […]
The tipping (tilting) pan filter obviously, and the rotary table filter somewhat less obviously, are developments of the simple batch vacuum filter described in the previous chapter. The single tipping pan is a batch filter, just like the Nutsche, but other versions, including the table filter, are intended to allow more or less continuous operation. […]
The next group of equipment types to be covered in this Section are all vacuum driven, and nearly all are intended for solids recovery, rather than for decontamination purposes. The simplest vacuum filter is the laboratory Büchner funnel, and the simplest practical embodiment of that is the Nutsche filter, which is found widely distributed throughout […]
Gyratory screen separators, which impart a basically circular motion to the particles on the screen, are used for high capacity separation by size of dry materials, and for wet separations when oversize material constitutes a large percentage of the feed (a typical example is shown in Figure 3.13 ). Common practice with gyratory screens has […]
A huge volume of solids is processed by means of vibratory screens. These can be either horizontal or gently inclined, and they incorporate the use of vibratory motors to achieve the required motion of the screen. In order to get flow of the separating solids across a horizontal screen, the vibrating motors need to run […]
The simplest form of size classification is the hand-held test sieve, fitted with a piece of precise wire mesh, and used to classify a sample of solids into two ranges of particle size – above and below the aperture of the mesh. These are used in the dry and shaken carefully and sufficiently to achieve […]
Well screens are sleeve-like units fitted over the ends of intake pipes in water or oil wells. They well illustrate the nomenclature problem outlined at the start of this chapter in that they are relatively small and clearly act entirely by straining, yet they have always been called screens, and so are described here. In […]
All of the intake screens discussed so far have operated in a stationary mode (or at least stationary whilst screening). An important group of screens rotate, screening solids continuously through that part of the screen that is submerged, with accumulated solids carried on the surface of the screen out of the water, to a zone […]
A different form of stationary water intake from surface water sources, such as submerged intakes for power, pulp and paper, or petrochemical industries, uses cylindrical screens at the inlet of the intake pipe, in single or multiple designs, as shown in Figure 3.9. These can usually be optimized to accommodate any set of conditions. In […]
A wide range of screens is used for the removal of solids from water in large-scale water handling systems. Where water is pumped from rivers or lakes (or from the sea, either as feed to a desalination plant, or for cooling purposes), screens are employed on the intake side to protect the pumps from debris […]
