Viscosity solids loading

There are essentially three different approaches to describing hindered settling. One approach is to define a correction factor to the Stokes free settling velocity in an infinite Newtonian fluid (which we will designate F0), as a function of the solids loading. A second approach is to consider the suspending fluid properties (e.g. viscosity and density) to be modified by the... 

For suspensions of fine particles, or systems containing a significant amount of fines, the suspending fluid can be considered to be homogeneous, with the density and viscosity modified by the presence of the fines. These properties depend primarily on the solids loading of the suspension, which may be described in terms of either the porosity or void fraction (s) or, more commonly, the volume fraction of solids, buoyant force on the particles is due to the difference in density between the solid (ps) and the surrounding suspension (p ), which is... 

There are several items for consideration in the operation of the circuit to minimize crud formation. In certain systems, solvent saturation can result in the formation of gelatinous solids, as in the rare earth-DEHPA system [50,55] and in the zirconium-TBP circuit [56]. The phenomenon is partially due to the increase in viscosity as loading is reached. An increase in the O/A ratio thus results in a decrease in crud formation. As the viscosity increases, excessive agitation can produce stable emulsions. 

Dioctyl azelate (trade name - Emolein) Dioctyl adipate (DOA) Bring down viscosity of HTPB and consequently, increase solids loading which improve performance of propellants and PBXs. 

Flow behavior also depends on the solids loading, which is the volume percent of the particles in the solution. The flow of a system can be categorized into two types viscous and viscoelastic. Viscous solutions are solutions where viscosity (t ) depends on the shear stress (x) and the shear rate (y) ... 

Hard sphere systems are characterized by viscous flow and for low solids loading (less than 5%) they can be described as Newtonian fluid. At higher loadings, cluster formation takes place and the fluid cau acquire shear thinning or thickening behavior. The viscosity and solids loading are correlated with the... 

FIGURE 11.13 Viscosity vs. volume solids loading. Krieger-Dougherty relation. For small loading (<5%) it is linear as predicted by Einstein. 

It is obvious that here is a direct correlation between the energy barrier created by the DLVO theory and the viscosity of the system. Due to the importance of viscosity in ceramic processing, those relations have been studied already. Empirical relations have been derived correlating those two magnitudes with temperature and solids loading dependence for Al203 ... 

The typical mass fraction of the solid in titrations is a few percent. Low-surface-area powders require a high solid-to-liquid ratio. Reference [554] reports titrations at a solid load as low as 1% by mass, and [44] reports titrations at a solid load as low as 0.75% by mass. The solid-to-liquid ratios in other studies were higher, and the upper limit of the solid-to-liquid ratio is determined by the viscosity of the dispersion. 

The effective volume fraction increases with a relative increase of the dispersant layer thickness. Even at 10% volume fraction, a maximum packing (< = 0.67) is soon reached, with an adsorbed layer thickness that is comparable to the particle radius. In this case, overlap of the steric layers wiU result in significant increases in viscosity. Such considerations may help to explain why solids loading can be severely Hmited, especially with small particles. In practice, soUds loading curves can be used to characterize the system, and take the form of those illustrated in Figure 11.6... 

When all the additives are added, the viscosity of sluny is about 4,000— 5,000 cps. At that time, solid loading of TZP, MZP and SUS316 are 25, 40 and 80 volume percent(vol%), respectively. Heating schedule is detennined by TG-DTA data[7], from which most of the binder is bumed-out below 500 °C. 

Because the relative densities of green and sintered body in gelcasting process have direct correlation with the solids loading of the slurry, many researchers focus on the preparation of concentrated slurry with low viscosity. Most of them have thought of an optimized circumstance of dispersant, pH, etc., to increase the solids loading of the slurry . ... 

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