Solvent-refined coal conversion

Chemical Week 1980, 128, pp 25-27. Rogers and Hill, Coal Conversion Comparisons, pp 69-71 Assessment of Technology for the Liquefaction of Coal, pp 111-15 Gulf Oil Corporation Information Brochure, "Solvent Refined Coal-II Environmental Issues and Protection Measures,"... 

One of the objectives of this work was to determine the effect of higher reactor pressure and space velocity on conversion and product quality. Heretofore, only temperature had been used to adjust or maintain conversion and product quality. Two different coal extract types were used in this study - namely, whole filter feeds obtained from Wilsonville short contact time coal extract (SCT) operations (Wilsonville run numbers 145 and 146 with 287 and 580 pounds of Indiana V coal feed per hour, respectively), and a conventional solvent refined coal (SRC-I)/ Koppers heavy residue creosote oil (KC-Oil) feed blend. The SRC-I was obtained from the Fort Lewis, Washington SRC-I facility... 

Hydroprocessing of Solvent Refined Coal (SRC-I) Extract , presented at Fifth International Conference on Coal Gasification, Liquefaction, and Conversion to Electricity, Pittsburgh, PA, August, 1978. 

Primary coal liquefaction products from three processes— solvent-refined coal, Synthoil, and H-Coal—were hydrotreated. Upgrading was measured in terms of the decrease in heptane and benzene insolubles, the decrease in sulfur, nitrogen, and oxygen, and the increase in hydrogen content. Hydrotreating substantially eliminated benzene insolubles and sulfur. An 85% conversion of heptane insolubles and an 80% conversion of nitrogen was obtained. Catalyst stability was affected by metals and particulates in the feedstocks. 

In this paper, we have described how minerals in coal can be quantitatively determined by the combination of SEM-AIA and Mi5ssbauer spectroscopy. These techniques can be applied to all coals, from lignite to anthracite, with little or no modification. Although such applications are not discussed in any detail here, these techniques can also be applied to cokes, chars, solvent-refined coals, and other products of coal conversion. 

The solvent refined coal (SRC) process has been conveniently described in two forms the SRC 1 process and the SRC 11 process (Schmid, 1975 Baughman, 1978). In the SRC I process, high-sulfur, high-ash coals are converted to a low-ash solid fuel whereas the SRC II process results in a liquid product (rather than a solid product) from a recycle of the product slurry, thereby increasing the conversion of the coal to lower molecular weight species (Figures 19.11 and 19.12). 

Synthetic Fuel. Solvent extraction has many appHcations in synthetic fuel technology such as the extraction of the Athabasca tar sands (qv) and Irish peat using / -pentane [109-66-0] (238) and a process for treating coal (qv) using a solvent under hydrogen (qv) (239). In the latter case, coal reacts with a minimum amount of hydrogen so that the solvent extracts valuable feedstock components before the soHd residue is burned. Solvent extraction is used in coal Hquefaction processes (240) and synthetic fuel refining (see Coal conversion processes Fuels, synthetic). 

Liquid Fuels. Liquid fuels can be obtained as by-products of low temperature carbonization by pyrolysis, solvent refining, or extraction and gasification followed by catalytic conversion of either the coal or the products from the coal. A continuing iaterest ia Hquid fuels has produced activity ia each of these areas (44—46). However, because cmde oil prices have historically remained below the price at which synthetic fuels can be produced, commercialization awaits an economic reversal. 

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. 

An array of products can be made via coal conversion processes. For example, refined coal tar is used in the manufacture of chemicals, such as creosote oil, naphthalene, phenol, and benzene. Ammonia gas recovered from coke ovens is used to manufacture ammonia salts, nitric acid, and agricultural fertilizers. Thousands of different products have coal or coal by-products as components soap, aspirins, solvents, dyes, plastics, and fibers, such as rayon and nylon. 

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