Liquid sizing

Preparation of Emulsions. An emulsion is a system ia which one Hquid is coUoidaHy dispersed ia another (see Emulsions). The general method for preparing an oil-ia-water emulsion is to combine the oil with a compatible fatty acid, such as an oleic, stearic, or rosia acid, and separately mix a proportionate quantity of an alkah, such as potassium hydroxide, with the water. The alkah solution should then be rapidly stirred to develop as much shear as possible while the oil phase is added. Use of a homogenizer to force the resulting emulsion through a fine orifice under pressure further reduces its oil particle size. Liquid oleic acid is a convenient fatty acid to use ia emulsions, as it is readily miscible with most oils. 

When sizing liquid control valves first use... 

Shell O.D., inches No. tubes Tube sheet faces Approx. area Vapor, inches Nozzle sizes Liquid, Steam, inches inches Cond., inches A inches B inches Dimensions C inches D inches E... 

R. L. Barton ( Sizing Liquid-Liquid Phase Separators Empirically, Chemical Engineering, July 8, 1974, Copyright (1974) McGraw-Hill, Inc., used with permission) provides the following quick method for sizing liquid-liquid phase sepai ators empirically. 

Barton, R. L., Sizing Liquid-Liquid Phase Separators Empirically, Chemical Engineering, July 8, 1974. 

Whenever two-phase flow is encountered in facility piping it is usually in flowlines and interfield transfer lines. Some designers size liquid lines downstream of control valves as two-phase lines. The amount of gas involved in these lines is low and thus the lines are often sized as singlephase liquid lines. Oversizing two-phase lines can lead to increased slugging and thus as small a diameter as possible should be used consistent with pressure drop available and velocity constraints discussed in Volume 1. 

The correlation factor, k, is a function of the liquid drop size, liquid viscosity, liquid load, disengaging space, type of mesh weave, etc. k varies somew hat with system pressure as pressure increases the k value decreases. The manufacturers should be consulted for final design k valves for a sys-... 

Roy et al. (R3) define the critical solids holdup as the maximum quantity of solids that can be held in suspension in an agitated liquid. They present measurements of this factor for various values of gas velocity, gas distribution, solid-particle size, liquid surface tension, liquid viscosity, and a solid-liquid wettability parameter, and they propose the following two correlations in terms of dimensionless groups containing these parameters ... 

Gap size, liquid thickness, thermal boundary layer... 

R. L. Barton6 provides the following quick method for sizing liquid-liquid phase separators empirically. 

The surface temperature of the droplet, 7 v. must first be solved using Eqs. (3) and (4), then the value ofB can be determined and substituted into Eq. (2). As an example, these equations were solved for a number of initial droplet sizes, liquids, and gas temperatures. The results are presented in Table 1 for the case of liquid evaporation into dry air (ybuik = 0). The results in Table 1, along with the form of Eq. (2), indicate that the time to evaporate... 

In Figure 3.48, the effect of particle size, liquid density, and liquid dynamic viscosity on wetting efficiency is presented. It is evident that by increasing particle size and liquid density, and decreasing liquid dynamic viscosity, the wetting efficiency is decreased. 

Figure 3.48 The effect of particle size, liquid density, and liquid dynamic viscosity on wetting efficiency.

Verzle (41) studied variables in preparative GC including column length, particle size, liquid substrate loading, and sample size. Studies showed that column length can be increased if mesh size of particles are decreased (larger particles). This permits reasonable flows of carrier gas with modest inlet pressures. 

A) Bolt, J. A., Boyle, T. A., Mirsky, W., "Generation and Burning of Uniform-Size Liquid Fuel Drops, Univ. of Mich., May 1953. 

Fig. 5.8. Laboratory-size liquid nitrogen Dewars, (a) Cross section of a wide-mouthed glass Dewar. These range in capacity from A to I L or larger, and are generally used to cool traps on vacuum systems. (/>) Cross section of a metal Dewar. To minimize liquid nitrogen losses, a loose-fitting cap is usually placed over the mouth of the Dewar.

Yamada, M., Seki, M., Nanoliter-Sized liquid dispenser array for multiple biochemical analysis in microfluidic devices. Anal. Chem. 2004, 76, 895-899. 

The quantity of starch transferred to paper by a size press depends on several factors concentration of dispersed starch in the surface size viscosity of the starch dispersion diameter of the size press rolls size press pond height cover hardness of the size press rolls size press nip loading pressure paper machine speeds wet-end sizing of the sheet and water content of the sheet. The concentration of starch in the surface size liquid can range from 2% to —15%, depending on product requirements. Frequently, pigments and other materials are added, which further increases total dispersed and suspended solids content. The viscosity ranges from water thin to several hundred cP (mPa-s). 

Figure 3. Permeability and pore number distributions versus pore size. Liquid-liquid displacement porosimetry measurements...

The common understanding of foam stability usually refers to the ability of a foam to maintain its main parameters constant with time, i.e. bubble size, liquid content (expansion ratio) and total foam volume. Foam lifetime is most often used as the simplest measure of foam stability. 

The rate of foam drainage is determined not only by the hydrodynamic characteristics of the foam (border shape and size, liquid phase viscosity, pressure gradient, mobility of the Iiquid/air interface, etc.) but also by the rate of internal foam (foam films and borders) collapse and the breakdown of the foam column. The decrease in the average foam dispersity (respectively the volume) leads the liberation of excess liquid which delays the establishment of hydrostatic equilibrium. However, liquid drainage causes an increase in the capillary and disjoining pressure, both of which accelerate further bubble coalescence and foam column breakdown. 

An extensive compilation was published by Rushton et al. (R13), giving the results of a program of measurements carried out by the Mixing Equipment Company. The data cover a wide range of impeller types, impeller and tank sizes, liquid properties, and operating conditions. They also presented their results in the form of a function of dimensionless groups ... 

Under trickle-flow conditions, determinations of the reactor conditions (i.e., gas and liquid flow rates, packing size, liquid properties, etc.) when all catalyst particles are effectively wetted and the catalyst surface is 100 percent utilized. 

The types of sedimentation encountered in process technology will be greatly affected not only by the obvious factors—particle size, liquid viscosity, solid and solution densities—but also by the characteristics of the particles within the slurry. These properties, as well as the process requirements, will help determine both the type of equipment which will achieve the desired ends most effectively and the testing methods to be used to select the equipment. 

Table 6.15 Summary of Equations for Sizing Liquid-Liquid Separators...

Barton, R.L., Sizing Liquid-Liquid Separators, Chem. Eng., 8l,.13, 111, 1974. 

R. J. Fontaine, R. S. Levine, and L. P. Combs, Secondary Nondestructive Instability in Medium Size Liquid Fuel Rocket Engines, in Advances in Tactical Propulsion, S. S. Penner, ed., AGARD Conference Proceedings no. 1, Maidenhead, England Technivision Services, 1968, 383-419. 

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