Liquid-solids velocity ratio

Denote the superficial liquid-solids velocity ratio (.L/pfA)/(S/psA) by N, and let (S/psut) =At. which is the minimal cross-sectional area if the solids were to flow at their terminal velocity, up in the absence of fluid flow, and can, therefore, be called terminal cross-sectional area. Then Eq. (2) can be reduced to a dimensionless form in terms of a reduced area, A, defined as follows... 

L/pj-A)(S/psA), liquid-solids velocity ratio, dimensionless Number of heat-transfer stages, dimensionless = hdp/kg, Nusselt number, dimensionless Pressure drop, gm-wt/cm2 = Cpu kg, Prandtl number, dimensionless = dpiipj U, Reynolds number, dimensionless S Mass velocity of solids, gm/cirf sec... 

Limestone is pulverized to 80 to 90 percent through 200 mesh. Shiny concentrations of 5 to 40% have been checked in pilot plants. Liquid to gas ratios are 0.2 to 0.3 gaLMSCF. Flue gas enters at 149°C (300°F) at a velocity of 2.44 m/s (8 ft/s). Utilization of 80 percent of the solid reagent may be approached. Flow is in parallel downward. Residence times are 10 to 12 s. At the outlet the particles are made just diy enough to keep from sticking to the wall, and the gas is within 11 to 28°C (20 to 50°F) of saturation. The fine powder is recovered with fabric filters. 

The flow pattern of fluids in gas-liquid-solid (catalyst) reactors is often far from ideal. Special care must be taken to avoid by-passing of the catalyst particles near the reactor walls, where the packing density of the catalyst pellets is lower than in the centre of the bed. By-passing becomes negligible if the ratio of reactor to particles diameter is larger than 10 a ratio of 20 is recommended. Flow maldistributions might be serious in the case of shallow beds. Special devices must be used to equalize the velocity over the cross-section of the reactor before reactants are introduced onto the catalyst bed. 

Onstream hours Fly ash loading Adipic acid concentration, ppm (controlled) Scrubber gas velocity, ft/sec Liquid-to-gas ratio, gal/Mcf Slurry solids concentration, wt % (controlled) Scrubber inlet pH (controlled) Oxidation tank level, ft Oxidation tank residence time, min Effluent hold tank residence time, min Average percent SO2 removal Average inlet SO2 concentration, ppm SO2 make-per-pass, m-moles/liter Percent oxidation of sulfite to sulfate Air stoichiometry, atoms oxygen/mole SO2 absorbed Oxidation tank pH Percent limestone utilization Scrubber inlet liquor gypsum saturation, % Filter cake solids content, wt % 1,688 High 1,300 1,700 5.4- 9.4 85 150 15 5.0- 5.1 18 2.8 8.3 93.4 2,660 4.0- 8.9 99.8 1.4- 2.4 4.9 92.6 93 86... 

Uie solid and liquid radial velocities must diflIer substantially for there to be an increase in the liquid solid ratio in the overflow, and vice versa in flie underflow, relative to the feed stream. 

The refractive index has as its basis the fact that light travels at a different velocity in condensed phases (liquids, solids) than in air. The refractive index n is defined as the ratio of the velocity of light in air to the velocity of light in the medium being... 

In the frame of equilibrium theory, which neglects mass transfer resistances and axial dispersion, true counter-current (TCC) adsorption model was employed in a series of efforts to obtain explicit expressions of the fluid to solid flow rate ratios, nij (j = l, - -4), for complete separation of binary mixtures [8-9, 20-23]. The operation condition of SMB was then determined based on the equivalence between SMB and TCC process by keeping constant the liquid velocity relative to the solid velocity in the two processes. In special, desorbent is usually nonadsorbable (or it is so weak that its adsorptivity is negligible) for enantiomeric separation, and explicit criteria were obtained [8] to determine the boundaries of the complete separation region in the space spanned by rrij j = 1, 4). It should be noted that the purity and yield of both components are 100 % in theory within the complete separation region. 

An extended investigation was done to determine relationships between two main hydrodynamic characteristics of capsule flow - capsule/liquid velocity ratio, Vc/ v< hydraulic gradient, ic, and parameters of capsule-liquid-pipe system, e.g. pipe diameter, D, capsule/pipe diameter ratio, d/D, capsule length/diameter ratio, l/d, capsule/carrier liquid density ratio. Pc Ipo, capsule shape, B, concentration of solids, Cv, liquid viscosity, po and liquid mean velocity, v<,. However, majority of the research was focussed on straight horizontal pipe. The knowledge about behaviour of capsules in bend or inclined pipe sections has been up to now insufficient. 

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