Single phase liquid mixing

In many instances, two or more miscible liquids must be mixed to give a product of a desired specification, such as, for example, in the blending of petroleum products of different viscosities. This is the simplest type of mixing as it involves neither heat nor mass transfer, nor indeed a chemical reaction. Even such simple operations can however pose problems when the two liquids have vastly different viscosities. Another example is the use of mechanical agitation to enhance the rates of heat and mass transfer between the wall of a vessel, or a coil, and the liquid. Additional complications arise in the case of highly viscous Newtonian and non-Newtonian liquids. 

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These expressions have been found valid for the range 1 < [(u,lug)NRtlNs< i] < 1000. For higher values, the axial mixing is identical to that observed for the single-phase liquid flow for which the following correlation was found for the experimental data ... 

A qualitative picture of the flow field created by an impeller in a mixing vessel in a single-phase liquid is useful in establishing whether there are stagnant or dead regions in the vessel, and whether or not particles are likely to be suspended. In addition, the efficiency of mixing equipment, as well as product quality, are influenced by the flow patterns prevailing in the vessel. 

During the mixing of a single-phase liquid in a stirred tank, the important parameters are the rate of power input, P, the impeller stirring speed, N, gravitational acceleration, g, the fluid density, p and viscosity, p, the impeller diameter, D and the other geometric characteristic lengths of the vessel (i.e. baffle width and depth, impeller shape,... 

By the use of measured volumes of liquid ozone at low temperature, liquid ozone-oxygen mixtures are prepared without ozone decomposition. Techniques for the preparation, mixing, disposal, and measurement of the physical properties of these mixtures are described at the liquid phase boundaries at —183 and —195.5° C., the specific volume of ozone-oxygen mixtures is additive within experimental error (0.005 gram per cc). The viscosity of solutions at —183° C. (on a log scale) varied linearly with the composition from 0.189 cp. for 100% oxygen to 1.57 cp. for 100% ozone. At —195.5° C., the viscosity of supercooled liquid ozone is 4.20 cp. Single phase liquid ozone-oxygen mixtures are Newtonian fluids. The surface tension of liquid ozone is 43.8 and 38.4 dynes per cm. at —195.5° and —183°C., respectively. The parachor of liquid ozone is 76.5. 

Combine all dry ingredients over 1-2 minutes while stirring using a paddle-type mixer. Heat Neodol surfactant until it is a single-phase liquid add the warm Neodol surfactant dropwise to the dry ingredients, stirring until evenly mixed. 

In view of our incomplete knowledge at present on the details of the turbulence in mixing vessels in the impeller region and in the bulk of the liquid in the vessel, the developments based on equations (8.22) to (8.24) should be interpreted with caution. More work is required to complete our knowledge even for a modest range of impeller designs with single-phase liquids. 

Consider a single-phase liquid in a stirred tank to which a volume of tracer material is added. The mixing time is the time measured from the instant of addition until the vessel contents have reached a specified degree of uniformity when the system is said to be mixed . 

Although the molecules of a single-phase liquid system may differ, and may diffuse at different rates, they will ultimately achieve a random distribution within the confines of the system. Particulate and granular components do not usually have the constant properties of molecular species and can differ widely in physical characteristics. Thus a mixing motion which depends on identical particulate properties is unlikely to achieve its objective. More commonly such a mixer would produce a grading or segregation of... 

It should be noted however that the enthalpy of mixing curve obtained for the section x(BaF2)/x(LiF) = 9/11 has an inflection point near x(NdF3) = 0.20 which can translate the appearance of a solid phase. Above this concentration, we cannot consider that the mixtures are single-phase liquids. 

The present volume deals with the mixing of two pure liquid components to form a binary homogeneous (single-phase) liquid system or a heterogeneous (two-phase) liquid-liquid system (Case a). All the components are well-defined pure substances. Only heat of mixing data obtained by direct calorimetric measurements are considered. 

Property Type [HMSDllll] HEAT OF MIXING AND SOLUTION State Two-component system, single-phase liquid or two-phase liquid-liquid (LL) Pure component 1, liquid Pure component 2, liquid Parameters 77K, Temperature Variables Xj/-, Mole fraction of component 1 //E/j mol-, Molar excess enthalpy Method Direct low-pressure calorimetric measurement of FP- at variable Xj and constant T ... 

Property Type [HMSDl 121] HEAT OF MIXING AND SOLUTION State Two-component system, single-phase liquid or two-phase liquid-liquid (LL)... 

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