Liquids, hydrocarbon content

Disposal of Drainage of Process Equipment Contents - When items of onsite process equipment are taken out of service, either individually during plant operation or for general turnaround, means of draining and safe disposal of the residual liquid hydrocarbon contents must be provided. The following are important considerations and terminology in the design ... 

The term inventory refers to liquid hydrocarbon contents at the top of the working level range. Tray holdup is included, but piping contents are disregarded. 

Table 1 provides a summary of the safe practices applied to the disposal of liquid hydrocarbon contents from various sources. 

A Presently available equations of state can be used to accurately calculate the water content of gas and hydrocarbon liquid phases but not the gaseous or liquid hydrocarbon content of the water phase. Equations of state can predict only qualitative results for the water phase. 

The yield of liquid products, including all hydrocarbons in the boiling range of gasoline as well as neohexane, is approximately 70 per cent by weight of the net consumption of ethane-propane and isobutane consumed during decomposition and alkylation. As the normally liquid hydrocarbon content of the coil effluent is increased from 20 to 35 per cent by weight (conversion per pass), the neohexane content of these liquids decreases from about 40 to about 30 per cent. 

Methanol eoncentration has essentially no effect on predicted water content of the liquid-hydrocarbon phase. The water eontent (not shown in the tables) was about 0.02 mol%. 

It is possible to produce some liquid hydrocarbons from most coals during conversion (pyrolysis and hydrogenation/ catalytic and via solvent refining)/ but the yield and hydrogen consumption required to achieve this yield can vary widely from coal to coal. The weight of data in the literature indicate that the liquid hydrocarbons are derived from the so-called reactive maceralS/ i.e. the vitrinites and exinites present (7 8 1 9). Thusf for coals of the same rank the yield of liquids during conversion would be expected to vary with the vitrinite plus exinite contents. This leads to the general question of effect of rank on the response of a vitrinite and on the yield of liquid products and/ in the context of Australian bituminous coals, where semi-fusinite is usually abundant/ of the role of this maceral in conversion. 

Purge gases used with liquid fluorine (—188°C or below) must be scrupulously dry and of low hydrocarbon content (<5 ppm), to prevent formation of ice crystals or solid hydrocarbons. 

The bulk of the naphtha was hydrotreated and catalytically reformed over a chlorided Pt/Al203-based catalyst to produce an aromatic motor gasoline. However, the hydrotreated Fischer-Tropsch naphtha is a poor feed for standard catalytic reforming on account of its high linear hydrocarbon content (>75%).37 In order to limit liquid yield loss, typical operation resulted in a reformate with quite low octane value (Table 18.10). Higher octane reformate could be produced, but at the expense of significant liquid yield loss. 

Wade and Quinn [12] measured the hydrocarbon content of sea surface and subsurface samples. Hydrocarbons were extracted from the samples and analysed by thin-layer and gas-liquid chromatography. The hydrocarbon content of the surface micro layer samples ranged from 14 to 599 pg/1 with an average of 155 pg/1, and the concentration in the subsurface samples ranged from 13 to 239 pg/1 and averaged 73 pg/1. Several isolated hydrocarbon fractions were analysed by infrared spectrometry and each fraction was found to contain a minimum of 95% hydrocarbon material, including both alkenes and aromatics. 

Zsolnay A (1974) Determination of aromatic and total hydrocarbon content in submicrogram and microgram quantities in aqueous systems by means of high-performance liquid chromatography. Special publication no. 409. National Bureau of Standards, Washington, DC, p 119... 

An oil containing 2.55 mole per cent of a hydrocarbon is stripped by running the oil down a column up which live steam is passed, so that 4 kmol of steam are used/100 kmol of oil stripped. Determine the number of theoretical plates required to reduce the hydrocarbon content to 0.05 mole per cent, assuming that the oil is non-volatile. The vapour-liquid relation of the hydrocarbon in the oil is given by ye = 33x, where ye is the mole fraction in the vapour and x the mole fraction in the liquid. The temperature is maintained constant by internal heating, so that steam does not condense in the tower. 

Although the calculated phase compositions for the hydrocarbon - rich liquid phase and the vapor phase showed excellent agreement with the experimental data, the calculated hydrocarbon contents of the aqueous liquid phase was consistently several orders of magnitude lower than the reported experimental values. 

One method (ASTM D6379, IP 436) is used to determine the mono- and diaromatic hydrocarbon contents in distillates boiling in the range 50 to 300°C (122 to 572°F). In the method the sample is diluted with an equal volume of a hydrocarbon such as heptane, and a fixed volume of this solution is injected into a high-performance liquid chromatograph fitted with a polar column where aromatic hydrocarbons are separated from nonaromatic hydrocarbons. The separation... 

Sulfur Poisoning. - Many conventional liquid hydrocarbon feeds contain large quantities of sulfur. For example, military diesel may contain as much as 3,000 ppm. Currently in the European Union the sulfur content in diesel is limited to 350 ppm, which was reduced to 50 ppm for both diesel and gasoline in 2005. Even with the pending limits on the sulfur content for U.S. fuels, deactivation by sulfur will be an ongoing concern. 

Gasworks cmde benzene and the lower boiling liquid products from low temperature carbonization, so-called fresh oil or low temperature spirit, are too low in aromatic hydrocarbon content to be refined economically to synthesis-grade benzene and toluene. Formedy, these fractions were used as a gasoline additive in the 1990s, the lower boiling liquid products are used as fuel at the refinery. 

Produced water from the condensate coolescers ond liquids separated in the Glycol Contactor Inlet Scrubber have a high hydrocarbon content ond connot be discharged directly into the droin caisson. This wet condensate streom is reinjected upstream of the Production Separator for reprocessing. 

Liquid Hydrocarbon Fuels Having High Volumetric Energy Content in J33 Single Combustor, Natl. Advisory Comm. Aeronaut. RM E50H28 (1950). 

The liquid crystalline regions obey the general rules for the liquid phases, but only where the hydrocarbon content is high. Along the water-emulsifier axis the changes with temperature are small in the PIT range this indicates that the structure of the liquid crystalline phase depends mainly on short range emulsifier-water interactions, which limits the solubility of water into the emulsifier. 

Water Content of Liquid Hydrocarbon in Equilibrium with Hydrates... 

This combination analysis was necessary in order to accurately determine both the hydrogen and hydrocarbon content of the gas as well as a density. The liquid samples only required analyses by the capillary column gas chromatograph. 

Asphaltite a variety of naturally occurring, dark brown to black, solid, nonvolatile bituminous material that is differentiated from bitumen primarily by a high content of material insoluble in n-pentane (asphaltene) or other liquid hydrocarbons. 

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