Volume and compression

The expansion of the reservoir fluids, which is a function of their volume and compressibility, act as a source of drive energy which can act to support primary producf/on from the reservoir. Primary production means using the natural energy stored in the reservoir as a drive mechanism for production. Secondary recovery would imply adding some energy to the reservoir by injecting fluids such as water or gas, to help to support the reservoir pressure as production takes place. 

Imai, T. Hirata, F., Partial molar volume and compressibility of a molecule with internal degrees of freedom., 7. Chem. Phys. 2003,119... 

Gritti, F. and Guiochon, G, Influence of the pressure on the properties of chromatographic columns, iii. Retention volume of thiourea, hold-up volume, and compressibility of the C-18-bonded layer, J. Chromatogr. A, 1075, 117, 2005. 

Knowledge of the sample pressure is essential in all high-pressure experiments. It is vital for determinations of equations of state, for comparisons with other experimental studies and for comparisons with theoretical calculations. Unfortunately, one cannot determine the sample pressure directly from the applied force on the anvils and their cross-sectional area, as losses due to friction and elastic deformation cannot be accurately accounted for. While an absolute pressure scale can be obtained from the volume and compressibility, by integration of the bulk modulus [109], the most commonly-employed methods to determine pressures in crystallographic experiments are to use a luminescent pressure sensor, or the known equation of state of a calibrant placed into the sample chamber with the sample. W.B. Holzapfel has recently reviewed both fluorescence and calibrant data with the aim of realising a practical pressure scale to 300 GPa [138]. 

Professor of physics at Cavendish Laboratory, Cambridge. He made elaborate investigations of the electrochemical equivalent of silver and of the combining volumes and compressibilities of gases. His observation that nitrogen prepared from the atmosphere is heavier than nitrogen prepared from ammonia led to the discovery of argon, the first noble gas. He also contributed to optics and acoustics. 

Physical properties are termed either intensive or extensive. Intensive properties are independent of the quantity of material present. Density, specific volume, and compressibility factor are examples. Properties such as volume and mass are termed extensive their values are determined by the total quantity of matter present. 

Figure 7.27. Efficiencies of centrifugal and reciprocating compressors, (a) Polytropic efficiencies of centrifugal compressors as a function of suction volume and compression ratio (Clark Brothers Co.), (b) Relation between isentropic and polytropic efficiencies, Eqs. (7.22) (7.23). (c) Isentropic efficiencies of reciprocating compressors (De Laval Handbook, McGraw-Hill, New York, 1970). Multiply by 0.95 for motor drive. Gas engines require 7000-8000 Btu/HP.

From studies of the concentration dependence of density and isentropic compressibility coefficients, the apparent molar volume and the isentropic apparent molar compressibility may be obtained above and below the CMC. Such studies have recently been performed for several systems by Brun, Holland and Vikingstad32,39-41 who deduced the change in partial molar volume and compressibility on micelle formation. This gives information on the counterion hydration and the packing of the hydrocarbon chains in the micelles. 

Introducing pressure into the FREZCHEM model necessitates quantifying volumetric properties of ions in solution and solids in order to calculate the pressure dependence of K (Eq. 2.29), 7 (Eq. 2.87), and aw (Eq. 2.90). Figures 3.6 and 3.7 depict the molar volumes and compressibilities of ions... 

The pressure dependence of equilibrium constants in this work are estimated with Eq. 2.29, which requires knowledge of the partial molar volumes and compressibilities for ions, water, and solid phases. For ions and water, molar volumes and compressibilities are known as a function of temperature (Table B.8 Eqs. 3.14 to 3.19). Molar volumes for solid phases are also known (Table B.9) unfortunately, the isothermal compressibilities for many solid phases are lacking (Millero 1983 Krumgalz et al. 1999). 

Pierrot D, Millero FJ (2000) The apparent molal volume and compressibility of seawater fit to the Pitzer equations. J Soln Chem 29 719-742... 

However, during long exposures to medium-temperature operating conditions, e.g. 1000°C, spinel formation is certainly expected. Wang etal.60 demonstrated this for the Ni-alumina system, showing the diffusion of Ni atoms to the free surface of the nanocomposite, followed by the formation of a nickel spinel surface coating which then limits the kinetics of subsequent oxidation. In this case the formation of a spinel surface layer may be beneficial to mechanical properties, since the reaction results in a volume increase, and the formation of compressive residual stresses. An analogous behavior was reported for ceramic particle nanocomposites, where oxidation of SiC particles results in an increase in volume and compressive residual stresses.61... 

Table 1.10. Selected values and parameters for ion partial molal volumes and compressibilities in seawater (from Millero, 1982b and 1983).

The stereochemistry of a solute is also important, as is shown by the differences between the partial molar volumes and compressibilities of stereoisomers of tartaric acid and its potassium salts in water (Mathieson and Conway, 1975). 

Matubayashi N, Levy RM (1996) Thermodynamics of the Hydration Shell, 2. Excess Volume and Compressibility of a Hydrophobic Solute. J. Phys. Chem. 100 2681-2688... 

Griineisen (1926) derived a semi-empirical relation between thermal expansion, specific heat, specific volume and compressibility for solid crystalline substances. 

To determine the in situ properties of the carbonate system in the ocean, it is necessaiy to determine the effect of pressure on the thermodynamic constants. This correction can be made in two ways (1) using direct measurements of the constants and (2) using partial molal volume and compressibility data (Mil-lero, 1979). The two methods are in good agreement (Millero, 1979) when comparisons are made for the carbonate system. The effect of pressure on the dissociation constants of acids (A ,) can be made from (Millero, 1979) equations... 

The coefficients in equations (26) and (27) for the dissociation of a number of acids and the solubility of calcium carbonate are given in Table A6.5 (Millero, 1979, 1995). The results for carbonic and boric acid are taken from the measurements of Culberson and Pytkowicz (1968). The effect of pressure on the solubility of calcite and aragonite has been determined from the measurements of Ingle (1975). The effect of pressure on the dissociation constants of water, hydrogen sulfate, hydrogen sulfide, ammonia, and hydroffuoric and phosphoric acids have been estimated from molal volume and compressibility data. 

Asano T, Tsubuku S, Sugawara S, et al. Changes in volume and compression energy upon compression of calcium silicate tablets. Drug Dev Ind Pharm 1997 23 679-685. 

Create a table that describes the three common states of matter in terms of their shape, volume, and compressibility. 

Naumov et al. (1974), Helgeson et al. (1981), Millero(1982), andTanger and Helgeson (1988) report molar volume data for aqueous species at 25°C. The last two references also give V° data for aqueous species from 0°C up to 50°C and 350°C, respectively. Molar compressibilities of minerals are available in Birch (1966) Mathieson and Conway (1974), and Millero (1982). Millero (1982) also lists values of AV° and AK° for aqueous species from 0 to 50 C. Molar volumes and compressibilities vary as a function of temperature and ionic strength (Millero 1982). Such effects may be important for aqueous species and especially for gases. 

Partial molar volumes and compressibilities of solutes at infinite dilution have proved valuable as a tool for studying water-solute interactions in aqueous solution, and a number of systems have been investigated. It has therefore been of interest to determine these quantities for solubilizates in the micellar state. By using Equation 6.23 these quantities can be obtained. 

If we look at the absolute values of partial molar volumes and compressibilites of alcohols solubilized in micelles, it appears that for the lower alcohols, up to heptanol, volumes and compressibilities exhibit lower values in SDS than in carboxylates. It also appears that the partial molar compressibilities of these alcohols are higher than the molar compressibility of the pure alcohols when solubilized in the carboxylate micelles and lower when solubilized in SDS. 

Usually, data are available to evaluate both of the straight derivatives in equation (7.108). This is not sufficient, however, to compute both AS / and A V/. Fortunately, A V/ may be obtained directly from data on molar volume and compressibility of the pure liquid. For the pure system s we have... 

The critical constants (temperature, pressure, volume and compressibility factor) have been determined experimentally and are available (1-7). Additional property data such as acentric factor, enthalpy of formation, lower explosion limit in air and solubility in water are also available (8-74). The property data in the top and middle parts of the tabulation are helpfiil in process engineering. The property data in the lower part of the tabulation are helpful in safety and environmental engineering. 

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