Cyclone cells

CYCLONE CELL Wilson Process Systems Limited 9 Waterworks Road Hastings... 

When the ore contains a large amount of clay minerals, these form difficult to separate slimes, which hinder the recovery of the minerals (see Clays). The tailing from the scavenger cells can be cycloned to remove the slimes before the coarse material is floated in a tailings retreatment plant. The flotation product from the rougher cells of this plant can be reground and cleaned. This additional treatment of the tailings from the main copper flotation plant may improve the recovery of metal values by 1—3%. 

Varied boiler firing configurations are found in hog fuel boiler applications, including dutch oven, fuel cell, spreader stoker with traveling or vibrating grates, and cyclone stoker types. As stated previously, the spreader stoker is the most widely used of these configurations. Spreader/stoker boilers in the pulp and paper industry often have an air swept spout added to the front of the boiler to feed bark down on top of the coal.14 Wood is puffed at one-... 

Froth flotation is an application of foams that is used to separate mineral components from each other based on their having different surface properties, typically their wettability and surface electrical charge. For example, froth flotation is the classic process used to separate copper from lead ore. The process involves having hydrophobic particles attach to gas bubbles which rise through a turbulent suspension to create a surface foam called a froth. Figure 10.2 shows an illustration of a mechanical flotation cell. This is the classic flotation device [53,91,625], First, the flotation feed particles are well dispersed into a particle suspension. Together with chemical flotation aids, such as collectors and frothers, this constitutes what is called the flotation pulp. In a mechanical flotation cell, air is fed in the form of fine bubbles and introduced near the impeller (see Figure 10.2). In addition to mechanical flotation cells, there are also pneumatic cells and cyclone flotation cells. Pneumatic... 

Levels of various elements such as As, Cd, Cr, Cu, Pb, Mi, Se, and Zn were reduced by 50% or more in some coals cleaned by combinations of heavy media cyclones, froth flotation cells, and hydraulic classifiers (21-24). Cleaning was less effective for other coals. 

Other elements were measured by a Perkin-Elmer SCIEX ELAN 6100 DRCII Inductively Coupled Plasma Mass Spectrometry (ICP-MS) instrument equipped with a cyclonic spray chamber, a concentric nebulizer and a dynamic reaction cell (DRC). In the vented (standard) mode, no reaction gas is present in the cell and the instrument shows the typical characteristics of a quadrupole-based ICP-MS apparatus. When the gas is introduced into the cell an ion-molecule reaction takes place that can be tailored so as to eliminate spectroscopic interferences. Experimental conditions are summarized in Table 10.2. 

To quantify the trace elements of interest plasma-based techniques were used, namely (i) ICP-AES using an Optima 3100 instrument (Perkin-Elmer, Norwalk, CT, USA) equipped with a cross-flow nebulizer and a Ryton Scott spray chamber (ii) Dynamic Reaction Cell (DRC) Q-ICP-MS using an Elan 6100 spectrometer (PerkinElmer, Norwalk, CT, USA) equipped with a quartz cross-flow Meinhard nebulizer and a cyclonic spray chamber (iii) SF-ICP-MS using an Elementl (ThermoElectron, Bremen, Germany) with a pneumatic nebulizer and a Ryton Scott spray chamber. 

In the South African mining industry most processes for recovering precious metals, coal, minerals and diamonds are wet methods, involving the suspension of solids in water [1], In the control of such wet abrasive conditions in the pumping of fine particles size slurries, particle size separation in cyclones and in floatation cells, the choice of soft natural rubber lining is the most cost effective. 

The extraction principles employed by most percolation extractors are the same, but the method by which each achieves countercurrent flow of solvent to flakes is different. The shallow-bed, chain extractor (Fig. 11.12), which resenibles a full-loop conveyor, is one of today s widely used extractors. Crown Iron Works (Minneapolis, MN) manufactures this type of extractor. In early versions that still exist in the industry, flakes are fed into an inlet hopper and are conveyed down the first leg of the loop where they are washed with moderately dilute miscella to extract surface oil and penetrate the cells. As the flake bed moves into the bottom horizontal section, full miscella is recycled through the bed for filtering, and then to a liquid cyclone for final... 

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