Filtration model

R. Dennis and co-workers, "Filtration Model for Coal Fly Ash with Glass Fabrics," EPA Rpt. EPA-600/7-77-095a, NTIS Pub. PB 276-489j MS, August 1977. 

Filtration. .. Section, Title. 1. Terminology. 2. Filtration Models.2.1. Cake Filtration Calculation of the Pressure Drop.. .. http.7/www.wiley-vch.de/contents/ullmann/ull 10295.html [More Results From www.wiley-vch.de]... 

DJ Mullan - Extended Abstract. .. Internal Cylindrical Compressible Cake Filtration Model. To date no one has developed a model which. .. http //www.und.ac.za/und/prg/posters/daveabs.html [More Results From www.und.ac.za]... 

The model proposed above is analogous to a continuous, unsteady state filtration process, and therefore may be called "Filtration Model". In this model, the concentration of the filtrate, viz. the concentration of the solute remained in the treated solid is one s major concern. This is given by the rate of Step 3, which may be expressed by an equation similar to Pick s Law including a transmission coefficient D for the porous medium, viz. the P.S.Z. and the concentration difference Aw across the P.S.Z. as the driving force, and the thickness of the P.S.Z. as the distance Ax. 

D may be evaluated by Equation 6 by using the experimental data of Wg as a function of z, w,(z). D as determined by Equation 6 is the differental which, according to the Filtration Model proposed, should vary almost linearly with the variation of W,. The rate of solute contamination by the surface adsorption usual increases as the solute concentration in the completely melted zone Wj increases. The integral coefficient may be evaluated by... 

The "Filtration Model" as proposed in this study represents the overall rate of the solute transfer (macro-segregation) in zone refining very well for a wide range of experimental conditions. 

This filtration theory and a local re-computation of the evolving unit-cell geometry due to deposition of particles (Fig. 13) was employed and a transient filtration model has been derived and tested with very good success against experimental data with ceramic, metallic and fibrous filters (Bissett and Shadman, 1985 Zarvalis et al., 2003). In addition, the same unit-cell-based... 

Fig. 13. Unit-cell filtration model. The collector size dc and the empty envelope b are matched to the macroscopic porosity of the filter. The unit-cell blocks when the size of the collector becomes a fraction of b (Konstandopoulos et al., 2000 Vlachos et al., 2002).

The filtration model gives the mass deposited across the wall thickness at different stages of the deep-bed filtration, which are reported as the utilized capacity of the filter wall, defined as ... 

Ho CC, Zydney AL (2000), A combined pore blockage and cake filtration model for protein fouling during microfiltration, J. Colloid Interface Sci. 232 389-399. 

Palacio, L., Ho, C.-C., and Zydney, A.L., Application of a pore-blockage—cake-filtration model to protein fouling during microfiltration, Biotech. Bioeng., 79, 260, 2002. 

Filtration Model. A model based on deep-bed filtration principles was proposed by Soo and Radke (12), who suggested that the emulsion droplets are not only retarded, but they are also captured in the pore constrictions. These droplets are captured in the porous medium by two types of capture mechanisms straining and interception. These were discussed earlier and are shown schematically in Figure 22. Straining capture occurs when an emulsion droplet gets trapped in a pore constriction of size smaller than its own diameter. Emulsion droplets can also attach themselves onto the rock surface and pore walls due to van der Waals, electrical, gravitational, and hydrodynamic forces. This mode of capture is denoted as interception. Capture of emulsion droplets reduces the effective pore diameter, diverts flow to the larger pores, and thereby effectively reduces permeability. 

As with PLA or PLG carriers, the application of either polyanhydride or polyorthoester polymers for 5-FU sustained release in glaucoma treatment or PVR has been investigated. Using compression techniques, polyanhydride devices constructed from combinations of(p-carboxyphenoxy)alkanes with sebacic acid have been produced. Disk or T-shaped polyanhydride devices containing between 10 and 20%i 5-FU prolonged lOP reduction and bleb survival in filtration models or... 

We wish to thank Roger Sigler and John Wiemik for conducting all performance testing and Randel Stong for his work in the development of the empirical filtration model. 

Particle concentration and size distribution in raw water have extensive and complex effects on the performance of individual treatment units (flocculator, sedimentation tank, and filter) and on the overall performance of water treatment plants. Mathematical models of each treatment unit were developed to evaluate the effects of various raw water characteristics and design parameters on plant performance. The flocculation and sedimentation models allow wide particle size distributions to be considered. The filtration model is restricted to homogeneous suspensions but does permit evaluation of filter ripening. The flocculation model is formulated to include simultaneous flocculation by Brownian diffusion and fluid shear, and the sedimentation model is constructed to consider simultaneous contacts by Brownian diffusion and differential settling. The predictions of the model are consistent with results in water treatment practice. 

The basic equation leads to four filtration models have been derived by Hermia (1982). By plotting t/V and Exp(t) over filtration time t and volume V, it is possible to determine which filtration mechanism is... 

The Cake Filtration Model describes the filtration of particles which are much larger than the pores and will be retained, without entering the pores. The particles deposit on the membrane surface contributing to the boundary layer resistance. Included in this model is deposition due to concentration polarisation. 

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