Dilute sedimentation

Site no. MSP Mutatox DR-CALUX (with clean-up dry sediment) Pore water ER-CALUX on polar fraction sediment YES on 10 X diluted sediment... 

For Cd no matrix interferences were observed from the increased sample mass. Nevertheless, all analyses were performed on the diluted sediment, because the Cd content of the sample met exactly the linear range of the Cd spectral line at 228.8 nm. The accuracy of the result was estimated at 10% (Is), so that a final result of 0.53 0.05 mg kg could be given. A homogeneity factor He =... 

Manganese measurements were performed on diluted sediment because the Mn concentration had to be determined on the poorly sensitive spectral line at... 

Lead measurements were carried out on both diluted and undiluted sediment. No matrix effects were observed, but the standard deviation for the diluted sediment was clearly lower. The accuracy of the result on the diluted sample was estimated at 10% (Is), so that a final result of 24.6 2.5 mg kg was obtained. On the undiluted sample a comparative value of 23 2.2 mg kg was produced (n = 11). A homogeneity factor He =2.88% x yfing was derived from these results, confirming the good homogeneity of the material for Pb. 

In dilute sedimentation the particle Reynolds numbers are usually low (< 1.0) and in this case the CovRe relation bip can be described sinq>]. Stokes solved the Navier-Stokes equation, which describes the bdiaviour of an infinitesimal elemwt of an incompressible fluid e q>eriencing only gravity as a body force, by assuming the inertia term to be negligible and produced ... 

Clarifier design has traditionally been based on the principle of dilute sedimentation. The design calculations of a clarifier include feed well design, sedimentation basin design (providing enough residence time for the separation), and solid flux (G). The other design parameters, such as the torque requirement and clarifier area, are similar to those of the thickeners, which have been discussed in the previous section (3.2.1). 

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