Solid concentration factor

As mentioned above, three factors are considered in the function which characterizes clogging first, the time factor, which is a consequence of the Poisson distribution of the pore surface that blocks evolution then the pressure factor, which accelerates the process of pore blocking and finally the solid concentration factor. 

The factors which may make CCD a preferred choice over other separation systems include the following rapidly settling solids, assisted by flocculation relatively high ratio of solids concentration between underflow and feed moderately high wash ratios allowable (2 to 4 times the volume of hquor in the thickened underflows) large quantity of sohds to be processed and the presence of fine-size sohds that are difficult to concentrate by other means. A technical feasibihty and economic study is desirable in order to make the optimum choice. 

In a hot gas expander, the major problems associated with catalyst fines are centered on erosion of components and particulate plugging. Either problem can cause machine vibration and sometimes power train emergency shutdown. Because many failures have resulted from these factors, machinery manufacturers recommend that the maximum permissible solids concentration upstream of an expander not exceed 200 ppm. It is further stipulated that 97% of the particles be smaller than 10 p. Allowing concentrations of 160 ppm with 95% of the particle less than 10 p is considered reasonable. 

In Figure 1 dashed squares refer to water bodies, while solid squares refer to solid matter (also containing some water). Plutonium may appear in any of these squares. The ratio of the concentration of plutonium in two adjacent squares is usually referred to as the concentration factor (CF usually from the water to the solid substance), the transfer coefficient (TC usually between two biological species), or the sorption ratio (or between minerals and water). To avoid ambiguity, we shall use the expression distribution coefficient (abbreviated Kd) with unit dimension (Pu amount per kg product divided by Pu amount per kg source). For the transfer of plutonium from A to B, Pu(A) ->- Pu(B), we define... 

Fig. 9-8 Histogram of dissolved solids of samples from the Orinoco and Amazon River basins and corresponding denudation rates for morpho-tectonic regions in the humid tropics of South America (Stal-lard, 1985). The approximate denudation scale is calculated as the product of dissolved solids concentrations, mean armual runoff (1 m/yr), and a correction factor to account for large ratios of suspended load in rivers that drain mountain belts and for the greater than average annual precipitation in the lowlands close to the equator. The correction factor was treated as a linear function of dissolved solids and ranged from 2 for the most dilute rivers (dissolved solids less than lOmg/L) to 4 for the most concentrated rivers (dissolved solids more than 1000 mg/L). Bedrock density is assumed to be 2.65 g/cm. (Reproduced with permission from R. F. Stallard (1988). Weathering and erosion in the humid tropics. In A. Lerman and M. Meybeck, Physical and Chemical Weathering in Geochemical Cycles," pp. 225-246, Kluwer Academic Publishers, Dordrecht, The Netherlands.)...

Continuous Operation This mode of operation is typical of paint recovery, whey processing, and wastewater processing where high solids and low fluxes require multiple passes, and continuous operation is allowed by the manufacturing process. For a feed concentration Cp, a volumetric concentration factor X (= retentate flow/feed flow), and retention R, the outlet retentate concentration is... 

All ore mineral deposits lie in or on solid rocks of which the Earth s crust is predominantly composed. The geological processes which are responsible for the formation of rocks also form the ore bodies associated with them. For the formation of an ore body, the metal or metals concerned must be enriched to a considerably higher level than their normal crustal abundance. The degree of such enrichment below which the extraction cost makes the processing of the ore uneconomical is termed the concentration factor. Typical values of the concentration factor for some of the common metals are given in Table 1.5. 

For a dust ignition to occur, the suspended solids concentration must lie between lower and upper limits which vary from material to material and are influenced by subtle factors such as particle shape and size distribution. From the standpoint of assessing safety hazards in commercial and industrial operations, the lower explosive limit is the more important one. The rationale of this statement is that, if the possibility of exceeding the lower limit in a powder-handling operation can not be completely ruled out, then a hazard must be recognized and appropriate measures taken. Over the... 

Combined results on ochre-precipitates and water from which they precipitate indicate strong enrichment regarding several relevant metals (Fig. 3). The concentration factor was estimated using the formulation by Munk et al. (2002), which calculates the ratio between the concentration of the elements in the solid and the concentration in the water. 

The most important factors in filter selection are the specific resistance of the filter cake, the quantity to be filtered, and the solids concentration. For free-filtering materials, a rotary vacuum filter is generally the most satisfactory since it has a very high capacity for its size and does not require any significant manual attention. If the cake has to be washed, the rotary drum is to be preferred to the rotary leaf. If a high degree of washing is required, however, it is usually desirable to repulp the filter cake and to filter a second time. 

Because of the low detection limit requirements, a concentration factor from the usual 1 litre of sample of between 1000- and 10 000-fold is required. This is usually achieved by solvent extraction, followed by evaporation of the extract to a small volume. However, the introduction of the Control Of Substances Hazardous to Health Regulation, 1989 (COSHH) has caused concern about the relatively large volumes of solvent used for extraction—especially chlorinated solvents such as dichloromethane. In order to reduce the volume of solvent used, solid phase extraction, using commercially available C 3 bonded-phase cartridges, is being introduced. 

Figure 4.9 Dependence of relative viscosity on solids concentrations for several values of apparent hydrodynamic shape factors. From J. S. Reed, Principles of Ceramics Processing, 2nd ed. Copyright 1995 by John Wiley Sons, Inc. This material is used by permission of John Wiley Sons, Inc.

Spray drying is the most widely used, least expensive and favored route among the methods available for encapsulation (2) Various theories of volatile retention in spray drying have been proposed and reviewed (3). In addition to the nature of flavor compounds, flavor retention is governed by type of carriers, infeed composition, solids concentration (4), dryer inlet/exit air temperature, air velocity and humidity, feeding rate and atomization characteristics. In addition to flavor retention,the stability of the encapsulated product, as mentioned earlier, is also of importance and is governed by nearly the same parameters. However,the effect and mechanics of each individual factor are much less understood. 

Many milk constituents affect the manufacturing and various characteristics of cheese, but milk fat and casein are of primary importance since they constitute most of the solids in cheese (e.g., 91% of the solids in Cheddar cheese). These two constituents, plus water, influence the yield of cheese from milk and the gross composition of cheese (Van Slyke and Price 1952). Formulas used to predict the cheese yield from milk include the concentration factors of casein and fat in milk, a minor correction factor for other milk constituents, and the added salt and moisture content of cheese (Van Slyke and Price 1952 Lelievre et al. 1983 Banks et al. 1984). 

Type of Centrifuge Continuous Automatically Discharged at Full Speed Automatically Discharged at Reduced Speed g-Factor Range IFC) Minimum Solid Concentration in Feed [% by Volume (C ) Possibility of Washing Minimum Particle Size, mm Minimum Filtrability Coefficient (fr)(m/sec) Maximum Retention Time (Sec)... 

The quantity of deposit control water treatment chemical required to be added to a cooling system per unit time (and hence the cost of the chemical program) is a function of the volume of makeup water added to the system and the cycles of concentration, or concentration factor of dissolved solids within the recirculating water. 

Many factors potentially can affect the distribution of an organic chemical between an aqueous and solid phase. These include environmental variables, such as temperature, ionic strength, dissolved organic matter concentration, and the presence of colloidal material, and surfactants and cosolvents. In addition, factors related specifically to the experimental determination of sorption coefficients, such as sorbent and solid concentrations, equilibration time, and phase separation technique, can also be important. A brief discussion of several of the more important factors affecting sorption coefficients follows. 

It has already been noted (Section 13.2) that the determination of solid-liquid distribution ratios (Kds) and, to a lesser extent, biological concentration factors... 

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