Wet natural gas

If a very lean glycol is required, it may be necessary to use stripping gas. A small amount of wet natural gas can be taken from the fuel stream or contactor inlet stream and injected into the reboiler. The stripping gas can be taken from the fuel stream or the contactor inlet stream and injected into the reboiler. The leaness" of the gas depends on the purity of the wet glycol and the number of stages below the reconcentrator. The stripping gas is saturated with water at the inlet temperature and pressure conditions. but adsorbs water at the reboiler conditions of atmospheric pres-... 

Thermosorption A process for recovering hydrocarbons from wet natural gas by adsorption on activated carbon. Offered by Lurgi. See also Supersorbon. 

The constituents of liquefied petroleum gas [propane (CH3CH2CH3) and/or butane (CH3CH2CH2CH3)] occur as constituents of wet natural gas or crude oil or as a by-product from refining. For example, a natural gasoline plant treats raw wet natural gas through absorption by washing with gas oil and fractionating out the usable traction. 

Saturated four-carbon hydrocarbons (butanes) occur in natural petroleum products such as crude oil and the heavy vapors in wet natural gas. The saturated C4s are also produced from other hydrocarbons during the various petroleum refining processes. The butylenes— unsaturated C4s—do not occur in nature, but are derived from butanes or other hydrocarbons either deliberately or as by-products. The complex interrelationships of C4 hydrocarbons, including their production and use, are described in Fig. 10.27. 

Derivation An important component of natural gasoline, refinery gases, wet natural gas also obtained by isomerization of butane. 

Natural Gas. Natural gas is the simplest source of hydrocarbon raw materials for chemicals since it consists of a small number of compounds which are easily separated. Nonhydrocarbon constituents include water vapor (up to 2.5% by volume, the saturation value), carbon dioxide (up to 95% from some wells in Mexico, New Mexico, and Colorado), inert gases (nitrogen and helium), and sulfur compounds (largely hydrogen sulfide). The hydrocarbon constituents of natural gas contain up to 8 carbon atoms. Wet natural gas contains larger proportions of the heavier hydrocarbons in this range. 

Natural Gasoline. Natural gasoline is produced from wet natural gas or from casing-head gas by compression or by absorption under pressure. Adsorption on carbon is another method of producing natural gasoline, but is little used in this country. Natural gasolines commonly are composed of C4 to Cs hydrocarbons. 

Wet natural gas contains natural gasoline in vapor form. The wet gas, also known as casinghead gas, is chiefly a mixture of methane, ethane, and the volatile hydrocarbons propane, butane, pentane (C5H12), hexane (CeH ), and heptane (C7H16). The latter three hydrocarbons form the main constituents of natural gasoline, which is recovered in refineries in liquid form mainly by absorption or compression processes. Pentane, hexane, and heptane are liquids under normal atmospheric conditions and are the chief components of ordinary refinery gasoline. 

Some industrial chemical processes involve no chemical reactions but only operations for separating chemicals and phases together with auxiliary equipment. A typical process is shown in Fig. 1.3, where wet natural gas is continuously separated into light paraffin hydrocarbons by a train of separators including an absorber, a reboiied absorber, and five distillation columns. Although not shown, additional separation operations may be required to dehydrate and sweeten the gas. Also, it is possible to remove nitrogen and helium, if desired. 

Havhk, W., Thayer, K., Obemdorfer, M. 2007. Production of wet natural gas containing corrosive components Four case histories. SPE Production and Operations 22 (3), pp. 319-325. 

In the widest sense, natural gas encompasses all gases that are produced in nature or emitted from the earth. In the more limited sense, however, natural gas is a gas with a high proportion of aliphatic hydrocarbons. European natural gas is rich in methane, whereas Saudi Arabian and American natural gas is relatively rich in higher hydrocarbons (Table 24-4). Since these higher hydrocarbons can be readily liquified, natural gas rich in C2 to C5 hydrocarbons has also been called wet natural gas. The wet American natural gases were the initial starting points of the petrochemical industry, from which, at first butene, later, also butane, was used to produce butadiene and a series of other monomers and intermediates. 

In the USA, and to some extent in Great Britain and Norway, ethane is the dominant feedstock for steam cracking. It is recovered from wet natural gas and gives high yields of ethylene, hydrogen and methane. From naphtha, the preferred feedstock in Europe and Japan, additional principal products are propylene, C4 hydrocarbons and pyrolysis naphtha as well as highly aromatic pyrolysis tar. 

Butane and propane (with other hydrocarbons in the paraffin series) are recovered from wet natural gas, from natural gas associated with or... 

Butane and propane (with other hydrocarbons in the paraffin series) are recovered from wet natural gas, from natural gas associated with or dissolved in crude oil, and from petroleum refinery gases. They may be separated from wet natural gas or crude oil through absorption in light mineral seal oil, through adsorption on surfaces such as activated charcoal, or by refrigeration, followed in each case by fractionation. Propylene and other gases in the monoolefin series are recovered from petroleum gases by fractionation. 

When natural gas is mostly pure methane, it is considered dry natural gas. When natural gas contains significant amounts of the heavier hydrocarbons including butane, it is considered wet natural gas. 

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