Recovery zones

Similarly, small (0.2—0.6 mm) air bubbles are introduced into a 2.6-m Deister Flotaire column at an intermediate level allowing rapid flotation of readily floatable material in the upper recovery zone. The bottom air permits longer retention time of the harder-to-float particles in the presence of micrometer-sized bubbles at a reduced downward velocity. The first commercial unit went on stream in 1986. It was used to improve the recovery of <0.6 mm (—28 mesh) coal in the plant s tailings. An average of 5.5% increase in coal recovery resulted from its use (14). The second commercial use processed <0.15 mm (—100 mesh) coal feed. 

Figure 22-8 shows the features of a horizontal center-fed column [Brodie, Au.st. Mech. Chem. Eng. Tran.s., 37 (May 1979)] which has been commercialized for continuous purification of naphthalene and p-dichlorobenzene. Liquid feed enters the column between the hot purifying section and the cold freezing or recovery zone. Ciystals are formed internally by indirect cooling of the melt through the walls of the refining and recovery zones. Residue liquid that has been depleted or product exits from the coldest section of the column. A spiral conveyor controls the transport of solids through the unit. 

The overall system that we will analyze comprises the unbleached Kraft pulp line, chemicals and energy recovery zones of a specific paper mill (Melville and Williams, 1977). We will employ a somewhat simplified but still realistic representation of the plant, originally developed in a series of research projects at Purdue University (Adler and Goodson, 1972 Foster et al., 1973 Melville and Williams, 1977). The records of simulated operation data, used to support the application of our learning architecture, were generated by a reimplementation, with only minor changes, of steady-state models (for each individual module and the system as a... 

Electrokinetics has been used to mobilize metals and dissolved contaminants to in situ treatment or recovery zones. Electrokinetic transport uses these mechanisms to move bacteria through the subsurface to the contaminated media. The technology can be used to treat organic contaminants that adsorb to aquifer soils including halogenated hydrocarbons and non-aqueous-phase liquids (NAPLs). 

Fig. 4. Schematic of cavitation bubbles interacting with a slurry of precipitated gel particles. The configuration shows typical two orifice processing as afforded in the CaviPro 300 processor. Cavitating bubbles initially form, expand in the recovery zone, and collapse with the formation of a microjet and shock wave.

CaviMax is a constant, high-flow-rate, single-orifice instrument with a maximum pressure of 8 MPa and orifices that can be interchanged in the range of 1.25 to 2.90 mm. The bubble dynamics can be further controlled through the use of a flow-throttling valve located just after the cavitation recovery zone. Other high-volume processors are available but were not used in this study. 

All refluxed melt will refreeze if reflux supplied equals that computed by Eq. (22-8). When reflux supplied is greater than the minimum, jacket cooling in the refining zone or additional cooling in the recovery zone is required to maintain product recovery. Since high-... 

From the beginning of the project, the average injection rate of polymer solution was kept dose to 420 m3/day. The cumulative volume of solution injected has been nearly equal to the cumulative volume of oil and water produced from wells located in the enhanced oil recovery zone (fig. 4 and 5). The polymer was diluted in treated field water. Produced formation water was separated from the oil and the sediments (shale particles) under anaerobic conditions and formaldehyde was added at an active concentration of 300 ppm to kill the bacteria. The water was then distributed to the polymer-mixing stations (fig. 6). The polymer was supplied in a water-oil emulsion form containing 30% active polymer dissolved in water. Because the continuous phase is oil, an inverter was added to the water before mixing. The polymer solution was then filtered through 10 micron screens before reinjection into the formation. 

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