Hydrodynamic sieving

Sorption- Diffusion Control Hydrodynamic Sieving-Control... 

Ultimately, strictly hydrodynamic sieving of a suspending solvent A (typically <3 1 A) away from suspended B becomes inadequate and molecular forces enter as dominant factors. Arguments are still heard regarding the need for combined hydrodynamic and molecular factors in NF separations. Nevertheless, the boundary at which molecular factors become dominant is typically set between ultrafiltration and nanofiltration for such pressure-driven cases. 

Of filtration opening size (FOS). O/ is comparable with O95 (hydrodynamic sieve method). 

J. Mlynarek, J. Lafleur, R. Rollin, G. Lombard, Filtration opening size of geotextiles by hydrodynamic sieving, ASTM Geotech Test J 16 (1) (1993) 61—69. 

Hydrodynamic sieving Alternating water flow Standard soil or glass beads mixture 257 24 CNR 145-CAN/CGS B 148.11... 

As stated by Giroud (1996) and Bhatia et al. (1994), electrostatic attraction occurs with glass beads that are smaller than 90 pm. This is the major drawback of dry sieving compared with wet and hydrodynamic sieving sieving in the presence of water eliminates electrostatic attraction. 

In hydrodynamic sieving, the soil particles (CNR 145) or glass beads (CAN/CGSB-148.11) tend to move across the specimen under the influence of a fluid drag force produced by an alternating flow of water. The geotextile specimens are inserted in the cylindrical specimen containers and the dry soil (according to CNR 145... 

Generally, the dry sieving method yields a relatively larger value of pore size than that obtained from either wet sieving or hydrodynamic sieving (Faure et al., 1986 Van der Sluys and Dierickx, 1991 Bhatia et al., 1994). This circumstance must be taken into account when design retention criteria are used. 

Bubble point, wet, and hydrodynamic sieving test results (Motad, 2010). 

In conclusion, the pore size results obtained by using bubble point or capillary flow tests (using pore wick or mineral oil with a contact angle equal to 0°), wet sieving tests, and hydrodynamic sieving tests are in good agreement. 

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