Substitution nature

Bi-Gas process A high-pressure operation for the conversion of solid fuel into substitute natural gas (SNG) using two stages of gasification. 

Carbon monoxide and excess steam are normally passed over a cobalt catalyst at about 250-300 C resulting in greater than 99% conversion of CO to COj. This conversion reaction is widely used in oil or solid fuel gasification processes for the production of town gas or substitute natural gas. ... 

SNG Substitute natural gas. soaps Sodium and potassium salts of fatty acids, particularly stearic, palmitic and oleic acids. Animal and vegetable oils and fats, from which soaps are prepared, consist essentially of the glyceryl esters of these acids. In soap manufacture the oil or fat is heated with dilute NaOH (less frequently KOH) solution in large vats. When hydrolysis is complete the soap is salted out , or precipitated from solution by addition of NaCl. The soap is then treated, as required, with perfumes, etc. and made into tablets. 

Table 2. Potential Substitute Natural Gas in United States from Biomass at Different Crop Yields...

Substitute or synthetic natural gas (SNG) has been known for several centuries. When SNG was first discovered, natural gas was largely unknown as a fuel and was more a religious phenomenon (see Gas, NATURAL) (1). Coal (qv) was the first significant source of substitute natural gas and in the early stages of SNG production the product was more commonly known under variations of the name coal gas (2,3). Whereas coal continues to be a principal source of substitute natural gas (4) a more recendy recognized source is petroleum (qv) (5). 

Table 3. Gas Composition Requirements for Substitute Natural Gas and for Power Generation...

Oil Shale. Oil shale (qv) is a sedimentary rock that contains organic matter, referred to as kerogen, and another natural resource of some consequence that could be exploited as a source of synthetic natural gas (67—69). However, as of this writing, oil shale has found Htde use as a source of substitute natural gas. 

There has been considerable research into the production of substitute natural gas (SNG) from fractions of cmde oil, coal, or biomass (see Euels SYNTHETIC, Euels frombiomass Euels fromwaste). The process involves partial oxidation of the feedstock to produce a synthesis gas containing carbon... 

In 1987 nonmotor fuel uses of butanes represented ca 16% of the total consumption. Liquid petroleum gas (LPG) is a mixture of butane and propane, typically in a ratio of 60 40 butane—propane however, the butane content can vary from 100 to 50% and less (see Liquefied petroleum gas). LPG is consumed as fuel in engines and in home, commercial, and industrial appHcations. Increasing amounts of LPG and butanes are used as feedstocks for substitute natural gas (SNG) plants (see Fuels, synthetic). / -Butane, propane, and isobutane are used alone or in mixture as hydrocarbon propellents in aerosols (qv). 

Synthesis gas is used in the production of substitute natural gas (SNG), ie, methane, and higher hydrocarbons. 

Properties. Thienamycin is isolated as a colorless, hygroscopic, zwitterionic soHd, although the majority of carbapenems have been obtained as sodium salts and, in the case of the sulfated olivanic acids, as disodium salts (12). Concentrated aqueous solutions of the carbapenems are generally unstable, particularly at low pH. AH the substituted natural products have characteristic uv absorption properties that are often used in assay procedures. The ir frequency of the P-lactam carbonyl is in the range 1760 1790 cm . ... 

Although the limited examples of AE reactions on 2,3Z-substituted allyl alcohols appear to give product epoxides in good enantioselectivity, the highly substituted nature of these olefins can have a deleterious effect on the reactivity. For example, Aiai has shown that the 2,3E-substituted allyl alcohol 30 can be epoxidized with either (-)-DET or (+)-DET in good yields and enantioselectivity. However, the configurational isomer 32 is completely unreactive using (-)-DET, even after a 34 h reaction time. 

More than 60 percent of natural gas physically consumed in the course of a year is nevertheless attributable to purchases at lower, interruptible prices by industrial boilcr-fucl users and electrical generators that are capable of substituting natural gas in off-peak months, when gas is available at prices competitive with those of black fuels (coal and heavy fuel oil). In addition to these relatively low-value, pricc-scnsitivc industrial gas uses is a wide range of intermediate-value demand categories for natural gas, such as in process and feedstock use. 

Coal, oil shale, and tar sand are complex carbonaceous raw materials and possible future energy and chemical sources. However, they must undergo lengthy and extensive processing before they yield fuels and chemicals similar to those produced from crude oils (substitute natural gas (SNG) and synthetic crudes from coal, tar sand and oil shale). These materials are discussed briefly at the end of this chapter. 

Rudolph, P. F., "The Lurgi Route to Substitute Natural Gas from Coal, ... 

Methanation Section Test Conditions. To date, the HYGAS pilot plant has been operated with Montana lignite coal feed. This lignite is a low sulfur (usually less than 1 wt % ) coal which has good reactivity for hydrogasification. The coal is nonagglomerating (thus eliminating the need for pretreatment), and it represents the lowest rank of U. S. coals that are available for conversion to substitute natural gas. 

Feed gases to most, if not all, methanation systems for substitute natural gas (SNG) production are theoretically capable of forming carbon. This potential also exists for feed gases to all first-stage shift converters operating in ammonia plants and in hydrogen production plants. However, it has been demonstrated commercially over a period of many years that carbon formation at inlet temperatures in shift converters is a relatively slow reaction and that, once shifted, the gas loses its potential for carbon formation. Carbon formation has not been a common problem at the inlet to shift converters. It has been no problem at all in our bench-scale work, and it is not expected to be a problem in our pilot plant operations. 

Development of the LPM process is included within the American Gas Association-United States Office of Coal Research joint program on producing substitute natural gas (SNG) from coal. The development program consists of three phases which are proceeding in an overlapping manner. These are reviewed in Table I. Completion of the program is scheduled for June 30, 1975. 

A further important industrial reaction is the water-gas shift reaction [Eq. (75)] which provides a way of increasing H2 CO ratios, or of producing pure H2. Pure H2 is needed for ammonia synthesis, 2H2 ICO is needed for methanol synthesis, and 3H2 lCO is used for synthesis of substitute natural gas. 

Gasmaco [Gas Machinery Company] A process for making a substitute natural gas from petroleum fractions and residues by thermal cracking. Developed from the Hall (2) process in the 1940s by the American Gas Association. See also Petrogas. 

Medium heating-value gas (10 to 20 MJ/m3 or 270 to 540 Btu/ft3) can be used as fuel gas for gas turbines in IGCC applications, for substitute natural gas (SNG) in combination with methanation process, for hydrogen production, for fuel cell feed, and for chemical and fuel synthesis. 

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