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Suspending physical parameters

Table 4 summarizes the efficiency of membrane filtration as preliminary treatment in the hybrid process to obtain regenerated water for industrial reuse. Working with the adequate cleaning cycle to avoid fouling and to keep a constant flux (10 1 min ) important reduction in suspended solids (90%) and turbidity (60%) of the wastewaters is achieved but there is no significant reduction of other chemical or physical parameters, e.g., conductivity, alkalinity or TDS, or inactivation of E. coli. [Pg.118]

Since physical parameters were held constant in these experiments, the theoretical single collector efficiency, r/(p, c)theor, is constant at 0.00256. The experimental attachment efficiency, a(p, c)exp, however, varies from 0.014 to 0.94, depending on the chemical composition of the solution. In the presence of a high concentration of Ca2+, the attachment coefficient approaches 1. This means that, in the absence of a repulsive chemical interaction, the mass-transport rale as calculated with Eq. 4 successfully describes the performance of these laboratory columns. At low ionic strength (pNa = 3.0), the sticking coefficient is reduced to a value of 0.014 by repulsive chemical interactions (presumably primarily electrostatic) between the suspended latex particles and the stationary glass collectors. Only 1.4% of the contacts produced by mass transport lead to attachment and deposition of the latex particles from the suspension. [Pg.452]

Suspension systems of sticky slurry and paste-like liquid explosives with solid particles, based on the dispersion of suspended solid particles, should belong to suspension or coarse multiphase systems in colloid chemistry. In these suspension systems, the main issue is its dynamic instability, because the density of the dispersed particles and the density of the dispersion medium are different (generally, the density particle is greater than that of the medium), settlement or floating can occur with the role of gravitational field to separate the system, resulting in unevenness in composition and density of liquid explosive. Stability is the ability to overcome the so-called sink-and-float separation of two-phase components, therefore, within a certain period of use, the composition and density of explosive and other physical parameters remained unchanged and its properties are stable and reliable. [Pg.137]

Suspended soiids 21 polyethylene bottle Same as for physical parameters... [Pg.4095]

The two steps in the removal of a particle from the Hquid phase by the filter medium are the transport of the suspended particle to the surface of the medium and interaction with the surface to form a bond strong enough to withstand the hydraulic stresses imposed on it by the passage of water over the surface. The transport step is influenced by such physical factors as concentration of the suspension, medium particle size, medium particle-size distribution, temperature, flow rate, and flow time. These parameters have been considered in various empirical relationships that help predict filter performance based on physical factors only (8,9). Attention has also been placed on the interaction between the particles and the filter surface. The mechanisms postulated are based on adsorption (qv) or specific chemical interactions (10). [Pg.276]

Winters and Lee134 describe a physically based model for adsorption kinetics for hydrophobic organic chemicals to and from suspended sediment and soil particles. The model requires determination of a single effective dififusivity parameter, which is predictable from compound solution diffusivity, the octanol-water partition coefficient, and the adsorbent organic content, density, and porosity. [Pg.829]

Chemical parameters determine the surface characteristics of the suspended colloids, the concentration of the coagulant and its effects upon the surface properties of the destabilized particles, and the influence of other constituents of the ionic medium upon the coagulant and the colloids. The extent of the chemical and physical interactions between the colloidal phase and the solution phase determines the relative stability of the suspended colloids. One speaks of stable suspensions when all collisions between the colloids induced by Brownian motion or by velocity gradients are completely elastic the colloidal particles continue their... [Pg.113]

Turbidity is a drinking water quality parameter and a groundwater well stabilization indicator. The clarity of water defines a physical property of turbidity. Suspended matter, such as clay and silt particles, organic matter, microscopic organisms, and colloids, causes natural waters to be turbid. Turbidity is measured optically as a lightscattering property of water. [Pg.172]

Reference conditions These are physical or chemical parameters that need to be assessed in conjunction with the analysis for standard compliance (e.g., temperature, pH, organic carbon content for soil or dissolved organic carbon, and total suspended solids for surface water) (depending on which factors influence chemical behavior and toxicity). [Pg.20]

In a search for the defining structural parameter of a composite, the free volume of disperse system proved to be the most sound one from the physical standpoint Presumably, for disperse systems the free volume is a measure of the mobility of filler particles, just as for liquids it is a measure of the mobility of molecules. But as applied to highly-loaded coarse systems of the type solid particles — liquid — gas this notion requires a certain correction. In characterizing the structure of such specific systems as highly-loaded coarse composites, it should be noted that to prevent their settling and separation into layers under the action of vibration, the concentration of the finest filler fraction with the largest specific surface in dispersion medium should be the maximum possible. Because of this and also because of the small size of particles (20-40 pm), the fine fraction suspended in the dispersion medium practically does not participate in the formation of the composite skeleton, which consists of coarser particles. Therefore... [Pg.139]

Finally, in chapter 6, another direction of applied electrochemistry is treated by Hovestad and Janssen Electroplating of Metal Matrix Composites by Codeposition of Suspended Particles. This is another area of metals materials-science where electroplating of a given metal is conducted in the presence of suspended particles, e.g. of A1203, BN, WC, SiC or TiC, which become electrodeposited as firmly bound occlusions. Such composite deposits have improved physical and electrochemical properties. Process parameters, and mechanisms and models of the codeposition processes are described in relation to bath... [Pg.553]

The introduction of biological and chemical threat agents into bodies of water poses several different problems. The nature of the problems posed will depend on the biological and physical properties of the threat agent used and the nature of the water body. To a large extent, the chemical characteristics of the biological and chemical agents (see Table 4.1) and the water quality parameters of a water body control solubility of the material as well as the sorption of the material to soil particles (suspended or bed sediments). Many of the transport phenomena are discussed in Chapter 3. [Pg.113]

Other than the product(s) list all components of streams exiting the process along with their key parameters. For example, for solids these could be the physical (particle size and distribution, bulk density, angle of repose, moisture content, etc.) and chemical (main and contaminants, separate or intermingled, etc.) characteristics and conditions for a waste liquid stream they could be content of water as well as organic and inorganic compounds (both dissolved and suspended), pH, surface tension, viscosity, etc.). [Pg.979]

The microbial activity or changes in some of the physical and chemical parameters described above (e.g., decreasing pH or increasing concentrations of organic ligands) may result in the desorption of nickel from suspended particulate material or sediment into water column (Di Toro et al ... [Pg.504]


See other pages where Suspending physical parameters is mentioned: [Pg.100]    [Pg.84]    [Pg.142]    [Pg.82]    [Pg.343]    [Pg.449]    [Pg.481]    [Pg.16]    [Pg.35]    [Pg.472]    [Pg.539]    [Pg.102]    [Pg.267]    [Pg.410]    [Pg.83]    [Pg.89]    [Pg.6]    [Pg.189]    [Pg.235]    [Pg.736]    [Pg.32]    [Pg.35]    [Pg.379]    [Pg.2520]    [Pg.72]    [Pg.611]    [Pg.1320]    [Pg.261]    [Pg.304]    [Pg.268]    [Pg.548]    [Pg.638]    [Pg.346]    [Pg.396]    [Pg.556]    [Pg.235]   
See also in sourсe #XX -- [ Pg.265 ]




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Physical parameters

Suspending

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