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Processing of Liquids

The processing of liquids with supercritical fluids mainly depends on their flow ability. Liquid feed materials of low viscosity like water-based solutions - for example, ethanol in water - are operated in high-pressure countercurrent columns that are [Pg.194]

With the aim of designing a high-pressure column process, some basic information is needed on the following  [Pg.195]

the distribution of the extract component between the feed and the contacting supercritical fluid is given by the phase equilibrium. The distribution coefficient relates the extract concentration in the supercritical phase to the extract concentration in the corresponding liquid phase at equilibrium conditions. Distribution coefficients have been evaluated for ternary systems in a broad range of [Pg.195]

Aiming separation of liquid mixtures with supercritical fluids, the governing mass transfer resistance normally exists in the liquid phase. Furthermore, the solvent-to-liquid ratios are high. Thus, the favored mode of operation is to run the supercritical solvent as the continuous phase. The liquid phase forms out thin films, rivulets, and droplets. The application of usual mass transfer equation Sh =f(Re, Sc) as given in Table 2.6, enables the calculation of mass transfer coefficients. However, in high-pressure countercurrent columns, one has to consider mutual mass transport. [Pg.196]

The hydrodynamic behavior of the countercurrent flow is of high importance because of the density difference between the two phases at high pressures. Thus, with increasing gas density, the risk of flooding the column reveals. In order to design a safe liquid dynamics of a supercritical countercurrent column process, Stockfleth [43] developed an equation nondependent on geometrical data that enabled the prediction of the flooding point. [Pg.197]


Let us consider one more physical phenomenon, which can influence upon PT sensitivity and efficiency. There is a process of liquid s penetration inside a capillary, physical nature of that is not obvious up to present time. Let us consider one-side-closed conical capillary immersed in a liquid. If a liquid wets capillary wall, it flows towards cannel s top due to capillary pressure pc. This process is very fast and capillary imbibition stage is going on until the liquid fills the channel up to the depth l , which corresponds the equality pcm = (Pc + Pa), where pa - atmospheric pressure and pcm - the pressure of compressed air blocked in the channel. [Pg.615]

Applicability This process is applicable to liquid (pumpable) organic wastes and finely divided, fluidizable sludges. It may be particularly applicable to the processing of liquid wastes with a high chlorine, pesticide, PCB or dioxin content. Sludges must be capable of being fluidized by the addition of a liquid. Waste streams must be free of (or preprocessed to remove) solids, which prevent satisfactory atomization. [Pg.160]

The process of liquid-liquid extraction, which includes the mixing of two immiscible fluids (emulsification) and separation of two immiscible fluids from the emulsion (settling), is applied in industry in one of the following three forms ... [Pg.269]

Leakage through a synthetic liner is controlled by Fick s first law, which applies to the process of liquid diffusion through the liner membrane. The diffusion process is similar to flow governed by Darcy s law except that it is driven by concentration gradients and not by hydraulic head. Diffusion rates in membranes are very low in comparison with hydraulic flow rates even in clays. In synthetic liners, therefore, the factor that most influences liner performance is penetrations. Synthetic liners may have imperfect seams or pinholes, which can greatly increase the amount of leachate that leaks out of the landfill. [Pg.1118]

Occasional or periodic process of liquid superheat and violent vaporization with possible expulsion and refilling... [Pg.487]

Romenets, V. A., Process of Liquid Phase Reduction of Iron Development and Implementation, Steel in the USSR, 20 366 (1990)... [Pg.676]

Vardanyan [65,66] discovered the phenomenon of CL in the reaction of peroxyl radicals with the aminyl radical. In the process of liquid-phase oxidation, CL results from the disproportionation reactions of primary and secondary peroxyl radicals, giving rise to trip-let-excited carbonyl compounds (see Chapter 2). The addition of an inhibitor reduces the concentration of peroxyl radicals and, hence, the rate of R02 disproportionation and the intensity of CL. As the inhibitor is consumed in the oxidized hydrocarbon the initial level of CL is recovered. On the other hand, the addition of primary and secondary aromatic amines to chlorobenzene containing some amounts of alcohols, esters, ethers, or water enhances the CL by 1.5 to 7 times [66]. This effect is probably due to the reaction of peroxyl radicals with the aminyl radical, since the addition of phenol to the reaction mixture under these conditions must extinguish CL. Indeed, the fast exchange reaction... [Pg.533]

In recent years many stalls have been equipped with batteries with manure belts. This type of battery is based on the processing of liquid manure. By removing the manure from the belts 2-3 times a week and storing it in properly closed cellars, good stall hygiene can be achieved. [Pg.179]

Electrochemical Processes of Liquid Lead in Molten Salts. 808... [Pg.804]

The kinetic theory of collisions, which has been so effective in developing the kinetics of vapor-phase reactions, has substantially influenced research on the processes of liquid-phase oxidation and in describing these processes. It has been thought that the lack of laws on which to base liquid-state theory (in contrast to the well-developed kinetic theory of gases) would in principle severely limit the development of a quantitative theory of liquid-phase reactions. At present the characteristics of the liquid state are carefully considered in discussing the mechanism of intermolecular reactions, influence of the medium on reactivity of compounds, etc. [Pg.14]

From its nature, a flavour is defined as a multicomponent blend of volatiles, non-volatiles and complex raw materials which is responsible for the final product properties. In flavour production, the volume-dominated operation units are mixing processes of liquids and dry blends. [Pg.482]

Liquid flavours can be divided into low-viscous liquids, medium-viscous liquids, emulsions, pastes and suspensions. The main processing of liquid flavour production is basically liquid blending. The most popular carriers for flavours for aqueous systems are ethanol, propylene glycol or glycerol. For fat-soluble flavours, triacetin or vegetable oils are the most important carriers. [Pg.482]

Document the results of the visual inspection process of liquid-hlled vials in attachment no 1700.110(C). [Pg.820]

Disperse systems often necessitate particle size reduction, whether it is an integral part of product processing, as in the process of liquid-liquid emulsification, or an additional requirement insofar as solid particle suspensions are concerned. (It should be noted that solid particles suspended in liquids often tend to agglomerate. Although milling of such suspensions tends to disrupt such agglomerates and produce a more homogeneous suspension. [Pg.101]

Natural Rubber and Synthetic Polyisoprene Polybutadiene and Its Copolymers Polyisobutylene and Its Copolymers Ethylene-Propylene Copolymers and Terpolymers Polychloroprene Silicone Elastomers Fluorocarbon Elastomers Fluorosilicone Elastomers Electron Beam Processing of Liquid Systems Grafting and Other Polymer Modifications... [Pg.9]

EXTRACTION (Liquid-Liquid). The physical process of liquid - liquid extraction separates a dissolved component from its solvent hy transfer to... [Pg.594]

Ac Klim. D. and A.A. Collyer Rheology und Processing of Liquid Crystal Polymers,... [Pg.1444]

However, interest in the process of liquid crystal formation is not... [Pg.103]

The appearance of a third phase, incompatible with the process of liquid-liquid extraction, requires the use of a phase modifier to eliminate or to restrict this phenomenon by increasing the solubility of extractant in the organic phase. This modifier can also enhance the extraction ability of the extractant. Often, this phase modifier is implemented without explanations on the contrary, the group of Oak Ridge undertook a thorough study, which will be described in the following paragraphs. [Pg.233]

Considering the process of liquid clathrate formation, solid-state liquid clathrate forming materials such as 13.21 are subject to a dissolution equilibrium or liquefying phase change upon exposure to aromatic solvents (Equation 13.1). [Pg.887]

Rieger R, Weiss C, Wigley G, Bart HJ, Marr R. Investigating the process of liquid-liquid extraction by means of CFD. Computers Chem Eng 1996 20 1467-1475. [Pg.370]

The mass transfer model. In our previous work [6] the mass transfer model equations and their mathematical treatment have been described extensively. The relevant differential equations, describing the process of liquid-phase diffusion and simultaneous reactions of the species according to the penetration theory, are summarized in table 1. Recently we derived from this penetration theory description a film model version, which is incorporated in the evaluation of the experimental results. Details on the film model version are given elsewhere [5]. [Pg.379]

Vitrification The process of liquid water moving directly into the glassy state without ice crystal formation... [Pg.113]

The -AG in Equation (1.80) is the useful work or net work at constant temperature and pressure to carry out the process not the work done by the expansion of volume. If a volume of the solution during the chemical or biological processes of liquids or solids does not increase, the work PAV is not useful for the process. [Pg.36]


See other pages where Processing of Liquids is mentioned: [Pg.197]    [Pg.6]    [Pg.80]    [Pg.47]    [Pg.406]    [Pg.83]    [Pg.110]    [Pg.77]    [Pg.150]    [Pg.190]    [Pg.208]    [Pg.361]    [Pg.203]    [Pg.118]    [Pg.95]    [Pg.109]    [Pg.62]    [Pg.69]    [Pg.1638]    [Pg.1]    [Pg.35]    [Pg.194]    [Pg.223]    [Pg.328]   


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Basic Physical Situations of Relevance in Gas-Liquid Processes

Electron Beam Processing of Liquid Systems

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Process Intensification in Vacuum Freeze-Drying of Liquids

The processing of liquid-crystal polymers

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