Volume of gases

Regnault s method Obsolete method for determining gas densities by direct weighing of a known volume of gas under known conditions of temperature and pressure. 

Black oils are a common category of reservoir fluids, and are similar to volatile oils in behaviour, except that they contain a lower fraction of volatile components and therefore require a much larger pressure drop below the bubble point before significant volumes of gas are released from solution. This is reflected by the position of the iso-vol lines in the phase diagram, where the lines of low liquid percentage are grouped around the dew point line. 

As the reservoir pressure drops from the initial reservoir pressure towards the bubble point pressure (PJ, the oil expands slightly according to its compressibility. However, once the pressure of the oil drops below the bubble point, gas is liberated from the oil, and the remaining oil occupies a smaller volume. The gas dissolved in the oil is called the solution gas, and the ratio of the volume gas dissolved per volume of oil is called the solution gas oil ratio (Rg, measured in scf/stb of sm /stm ). Above the bubble point, Rg is constant and is known as the initial solution gas oil ratio (Rgj), but as the pressure falls below the bubble point and solution gas is liberated, Rg decreases. The volume of gas liberated is (Rg - Rg) scf/stb. 

Because the neutron tool responds to hydrogen it can be used to differentiate between gas and liquids (oil or water) in the formation. A specific volume of gas will contain a lot fewer hydrogen atoms than the same volume of oil or water (at the same pressure), and therefore in a gas bearing reservoir the neutron porosity (which assumes the tool is... 

The typical compressibility of gas is 500 10 psi, compared to oil at 10 10 psr, and water at 3 10 psi When a volume of gas is produced (8V) from a gas-in-place volume (V), the fractional change in pressure (8P) is therefore small. Because of the high compressibility of gas it is therefore uncommon to attempt to support the reservoir pressure by injection of water, and the reservoir is simply depleted or blown down . 

As solution gas drive reservoirs lose pressure, produced GORs increase and larger volumes of gas require processing. Oil production can become constrained by gas handling capacity, for example by the limited compression facilities. It may be possible to install additional equipment, but the added operating cost towards the end of field life is often unattractive, and may ultimately contribute to increased abandonment costs. 

Flere is the volume of gas required to saturate the monolayer, V the total volume of gas adsorbed, P the sample pressure, P the saturation vapour pressure and C a constant related to the enthalpy of adsorption. The resulting shape of the isothemi is shown plotted in figure Bl.26.6 for C = 500. A plot of P/V(P - Pq) against P/Pq should give a straight line having a slope (C - )/y C and an intercept The BET surface area is... 

No reaction with nitrogen oxide Phosphorus burns leaving an equal volume of gas (nitrogen)... 

Shortly after publication of Dalton s New System of Chemical Philosophy Gay-Tussac announced his observations that volumes of gas which combine with each other and the volume of the combination thus formed are in direct proportion to the sum of the volumes of the constituent gases. The volumetric proportions of Gay-Tussac and Dalton s gravimetric ratios indeed supplement each other, although they themselves contested and rejected each other s concepts. 

The heats of combustion of methane and butane are 890 kj/mol (212 8 kcal/mol) and 2876 kJ/mol (687 4 kcal/mol) respectively When used as a fuel would methane or butane generate more heat for the same mass of gas" Which would generate more heat for the same volume of gas" ... 

The column (or line entry) headed a gives the volume of gas (in milliliters) measured at standard conditions (0°C and 760 mm or 101.325 kN dissolved in 1 mL of water at the temperature stated (in degrees Celsius) and when the pressure of the gas without that of the water vapor is 760 mm. The line entry A indicates the same quantity except that the gas itself is at the uniform pressure of 760 mm when in equilibrium with water. 

The quantity of gas adsorbed may of course be expressed in other ways, notably as the mass of gas (usually mg) or the volume of gas reduced to stp (usually cm (stp)). Unless immediate convenience dictates otherwise, however, the use of moles (or in some contexts, molecules) is to be preferred. In particular the common but loose expression volume of gas adsorbed at pressure p is highly ambiguous. 

Nonvolatile compounds are normally present either as solid particulates or bound to solid particulates. Samples are collected by pulling large volumes of gas through a filtering unit where the particulates are collected on glass fiber filters. 

Gas-Cycle Systems. In principle, any permanent gas can be used for the closed gas-cycle refrigeration system however, the prevailing gas that is used is air. In the gas-cycle system operating on the Brayton cycle, all of the heat-transfer operations involve only sensible heat of the gas. Efficiencies are low because of the large volume of gas that must be handled for a relatively small refrigera tion effect. The advantage of air is that it is safe and inexpensive. 

The Reich test is used to estimate sulfur dioxide content of a gas by measuring the volume of gas required to decolorize a standard iodine solution (274). Equipment has been developed commercially for continuous monitoring of stack gas by measuring the near-ultraviolet absorption bands of sulfur dioxide (275—277). The deterrnination of sulfur dioxide in food is conducted by distilling the sulfur dioxide from the acidulated sample into a solution of hydrogen peroxide, foUowed by acidimetric titration of the sulfuric acid thus produced (278). Analytical methods for sulfur dioxide have been reviewed (279). 

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