Composition of gas

Cmde gas leaves from the top of the gasifier at 288—593°C depending on the type of coal used. The composition of gas also depends on the type of coal and is notable for the relatively high methane content when contrasted to gases produced at lower pressures or higher temperatures. These gas products can be used as produced for electric power production or can be treated to remove carbon dioxide and hydrocarbons to provide synthesis gas for ammonia, methanol, and synthetic oil production. The gas is made suitable for methanation, to produce synthetic natural gas, by a partial shift and carbon dioxide and sulfur removal. 

Table 1.1 Equilibrium composition of gas mixtures at 2300 K and 0.1 atmos pressure (mole fraetions of the major gases only)...

The two major conditions that promote hydrate formation are (1) the gas being at the appropriate temperature and pressure, and (2) the gas being at or below its water dew point with free water present. For any particular composition of gas at a given pressure there is a temperature below which hydrates will form and above which hydrates will not form. As the pressure increases, the hydrate formation temperature also increases. If there is no... 

The presence of nitrate as acelerator has a pronounced effect on the amount and composition of gas evolved from the work being treated (Table 15.8). It will be observed that hydrogen evolution drops to a very low figure with the zinc/nitrate baths. The formation of nitrite arises from decomposition of nitrate by reaction with primary ferrous phosphate to form ferric phosphate ... 

The accurate composition of the gas hydrates for a long time remained a controversial subject, since direct analysis leads to ambiguous results owing to decomposition of the hydrate and/or inclusion of mother liquor in the crystals. Thus it was firmly believed that the nonstoichiometric compositions of gas hydrates found experimentally were all due to errors in the analysis. But more recent determinations of the composition by the indirect... 

The mobility of gases in the firn column leads to temperature-dependent changes in the composition of gas trapped in ice at the base of the fim (Severinghaus et ah, 1998). If there is a rapid change in climatic temperature at the ice-sheet surface, a steep temperature gradient will temporarily exist throughout the firn. This will temporarily cause thermal fractionation of gas-... 

By an analysis of the composition of gas or liquid stream and the arrangement or conditions at the particular facility one can prudently arrive at the optimum detection philosophy. 

Table 5.1. Compositions of Gas Mixtures and Associated Wavelengths Commonly Used in Excimer Lasers...

Henry constant (mmol-L -bar ) acidity constant of the couple (C02-Bicarbonate) composition of gas in A (%) liquid-gas exchange constant (day ) standard deviation of the variable A... 

Infrared (IR) spectroscopy offers many unique advantages for measurements within an industrial environment, whether they are for environmental or for production-based applications. Historically, the technique has been used for a broad range of applications ranging from the composition of gas and/or liquid mixtures to the analysis of trace components for gas purity or environmental analysis. The instrumentation used ranges in complexity from simple filter-based photometers to optomechanically complicated devices, such as Fourier transform infrared (FTIR) spectrometers. Simple nondispersive infrared (NDIR) insttuments are in common use for measurements that feature well-defined methods of analysis, such as the analysis of combustion gases for carbon oxides and hydrocarbons. For more complex measurements it is normally necessary to obtain a greater amount of spectral information, and so either Ml-spectrum or multiple wavelength analyzers are required. 

McFarland, D. F., Composition of gas from a well at Dexter, Kansas," Trans. 

Evolved gas analysis Nature and composition of gas liberated during thermal analysis. Gas analyzer... 

As discussed in the previous section, gas oils are complicated mixtures of several different hydrocarbon classes contaminated with small amounts of sulfur-containing species that lower product quality and limit marketability of the whole gas oil (see Fig. 1). The concentration of these sulfur species must be lowered significantly to meet present standards and, in the future, they must be nearly completely removed. To understand the difficulties in such conversions, it is helpful to consider the detailed composition of gas oils, from both the viewpoint of the desirable components of gas oils which are not to be converted and that of the sulfur-containing species which must be treated to extinction. 

Figure 7.2-2. Composition of gas from decomposition during homopolymerization of ethylene [3]. A, CH4 B, H2 C, C2H4 D, C2H6 solid line, 200°C, dashed line, 300°C.

The bubble-point line is also the locus of compositions of the liquid when two phases are present. The dew-point line is tire locus of compositions of the gas when gas and liquid are in equilibrium. The line which ties the composition of the liquid with the composition of gas in equilibrium is known as an equilibrium tie-line. Tie-lines are always horizontal for two-component mixtures. 

Component Composition of liquid, mole percent Composition of gas, mole percent... 

The compositions of gas and liquid samples taken from a separator are given below. The separator was stabilized at 945 scf/STB. Laboratory measurement indicated a separator/stock-tank volume ratio of 1.052 SP bbl/STB. The density of the separator liquid, calculated with procedures given in Chapter 11, is 49.8 lb/cu ft at separator conditions of 115 psia and 100°F. 

Component Composition of mixture, mole fraction zl Vapor pressure at 150°F, P i Composition of gas, mole fraction yi=zjf1 +ndp/t>v -1) Composition of liquid, mole fraction xi=yi(p/pvj)... 

Expt. No. Time mins Moles of gas per mole of Tetryl Composition of dry gas, vol % Composition of gas, moles per mole of Tetryl ... 

Lorenson, T.D., Collett, T.S., Gas content and composition of gas hydrate from sediments of the southeastern North American continental margin, in Proc. ODP, Sci. Results, (Pauli, C.K., Matsumoto, R., Wallace, P.J., and Dillon, W.P. eds.), College Station, TX (Ocean Drilling Program), 164, 37—46 (2000). 

Figure 2. Changes in the isotopic composition of gas phase oxygen and declines of 0 isotope content of gaseous oxygen or nitric oxide as a function of illumination time for preoxidized Ti02 samples.

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