Solvent-refined coal II

Gulf Oil Corporation, Information Brochure, "Solvent Refined Coal-II Turning Coal into Clean Energy," pp 4-5 Assessment of Technology for the Liquefaction of Coal, The National Research Council, Washington, 1977, pp 47-50. 

Gulf Oil Corporation, Information Brochure, "Solvent Refined Coal-II Background and Schedule."... 

Gulf Research/Tacoma, Washington [D0E/0R/03055-72, Feb 82] Solvent Refined Coal-II (Full Range Mixture)... 

Solvent Refined Coal-II (Middle Distillate Fraction)... 

The test material used In these experiments was CRM-1, a coal-oll comparative research material obtained from Oak Ridge National Laboratory. CRM-1 Is a liquid product from the SRC-II (solvent-refIned-coal-II) process and Is a mixture of middle and heavy distillates In a ratio of 2.9 to 1. Aqueous solutions of the test material were prepared by stirring crude CRM-1 with distilled water In 1-gal solvent bottles at a level of 2 g/L for five days. After equilibration, undlssolved oil was removed by passing the sample through a coarse glass frit, followed by filtration through a 0.45-U membrane filter three times to ensure a true aqueous solution with no visible droplets of undlssolved oil. 

Inspection of Products from the Solvent-Refined Coal II (SRC II) Process (See Also Table 19.5)... 

Solvent Refined Coal Process. Work ia the mid-1960s by the Speacer Chemical Co. (9) and dating the 1970s by the Gulf Chemical Corp. led to two solvent refined coal (SRC) processiag schemes SRC-I for productioa of low ash soHd boiler fuels and SRC-II for distillates, eg, "syn-cmde."... 

Solvent-Refined Coal Process. In the 1920s the anthracene oil fraction recovered from pyrolysis, or coking, of coal was utilized to extract 35—40% of bituminous coals at low pressures for the purpose of manufacturing low cost newspaper inks (113). Tetralin was found to have higher solvent power for coals, and the I. G. Farben Pott-Broche process (114) was developed, wherein a mixture of cresol and tetralin was used to dissolve ca 75% of brown coals at 13.8 MPa (2000 psi) and 427°C. The extract was filtered, and the filtrate vacuum distilled. The overhead was distilled a second time at atmospheric pressure to separate solvent, which was recycled to extraction, and a heavier liquid, which was sent to hydrogenation. The bottoms product from vacuum distillation, or solvent-extracted coal, was carbonized to produce electrode carbon. Filter cake from the filters was coked in rotary kilns for tar and oil recovery. A variety of liquid products were obtained from the solvent extraction-hydrogenation system (113). A similar process was employed in Japan during Wodd War II to produce electrode coke, asphalt (qv), and carbonized fuel briquettes (115). 

PANELIST SCHMID Several years ago we made a comparative economics study between SRC-I and SRC-II. The results then indicated that the overall selling price would be about the same for the two products namely, a liquid fuel oil of about. 3% sulfur from SRC-II versus a solid solvent refined coal containing about. 8% sulfur from SRC-I. Obviously, there is a substantial difference in the quality of the two products in favor of SRC-II. 

SRC II (Solvent-Refined Coal (SRC) II, Pittsburg and Midway Coal Mining Co.)—hydroliquefaction of coal with slurry recycle, 25.3 wt % on dry Western Kentucky coal, < 10 cP 850°F endpoint. 

Test Samples. Main properties of the residual oils used in the present test are represented in Table II. It should be noted in this table that No. 1 is propane deasphalted asphalt Nos. 2 to 7 are petroleum pitches derived from residual oil heat treated under various conditions No. 8 is KRP pitch made by Kureha Chemical Industry from crude oil heat treated with hot steam at temperatures over 1,000°C and Nos. 9 and 10 are both residual oils from coal, No. 9 being solvent refined coal made by NKK and No, 10 being heat treated coal tar pitch. These Nos. 1 to 10 are typical examples of binding material for coke-making in Japan. 

Fig. 19.19. Block flow diagram of SRC-II process for solvent refined coal. (CourtesyThe Pace Company, Denver, CO.)...

Solvent-Refined Coal. The solvent-refined coal (SRC 1) process (40) produces a low-sulfur, low-ash solid fuel from coal. Through the courtesy of L. Taylor, samples of SRC produced from five different feed coals were made available to us for ESR studies. Each of the five samples gave a strong ESR resonance near g=2 g values and spectral line widths are summarized in Table II. The g value and line width data, viewed collectively, suggest the presence of organic free radicals, with only minor interaction (except possibly for the Monterey sample) between the unpaired electrons and heteroatoms in the samples. 

Table II. ESR g Values and Spectral Line Widths for Selected Samples of Solvent-Refined Coal...

The solvent-refined coal (SRC) processes were originally developed to produce cleaner boiler fuels from coal. A 0.5t/day plant was built in 1965 and scaled up in 1974 into two separate pilot plants located at Wilsonville (SRC-I, 6t/day) and Fort Lewis, WA (SRC-I, 50t/day). The Fort Lewis plant was later converted to an SRC-II unit. Due to the more severe conditions required for SRC-II, the capacity was downgraded to about 25 t/day. The objective of the SRC-II process was to produce distillate products. Detailed designs for large-scale plant were subsequently prepared, although these plants were not built. The Wilsonville plant continued to be funded... 

Tomlinson, G., Gray, D., and Neuworth, M., "Effect of Coal Rank on Direct Coal Liquefaction Processes Solvent Refined Coal (SRC-II) Process Experience," The MITRE Corp., 84W00308, July 1984. 

During the past 7 years, we have developed and applied new methodologies using capillary-column GC for the separation and identification of PACs in coal-derived liquids. The primary samples that were used throughout these studies included a solvent-refined coal (SRC II) heavy distillate and a coal tar. Details of the isolation and identification of polynuclear aromatic hydrocarbons (PAHs) (II), sulfur heterocycles (12, 13), nitrogen heterocycles (14,15), amino- substituted PACs (16-18), and hydroxy-substituted PACs (14, 19, 20) in an SRC II heavy distillate have already been published (II, 13, 15, 18, 21). 

The solvent-refined coal heavy distillate (SRC II HD, bp 260-450 °C) that was analyzed and used in this study was collected during the processing of a West Virginia coal from the Pittsburgh seam. Data from the analysis of a solvent-refined coal vacuum residue (SRC II VR) from the same process was also used. A coal tar was obtained from the National Bureau of Standards. This tar was a medium crude coke-oven tar... 

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). 

The solvent-refined coal (SRC-II) process is an advanced process developed by Gulf Mineral Resources Ltd. to produce a clean, nonpolluting liquid fuel from high sulfur bituminous... 

The first process was studied by Berthelot in 1867 and was further developed in Germany by Bergius in 1910. The early Bergius process involved the reaction of H2 under atmospheric pressure with pulverized coal suspended in an oil heated to about 450°C in the presence of a catalyst such as stannous formate or Mo. The liquid oil product is separated from the solid residue and processed as ordinary crude oil. Modem developments in this coal liquefaction approach include (1) Exxon Donner Solvent (EDS) process, (2) the HRI H-Coal process, and (3) the Gulf Solvent Refined Coal SRC-II process. The major improvement of these processes over the Bergius process is in the catalyst used, allowing for milder reaction conditions. 

The solvent refined coal (SRC) process began as a study on the feasibility of coal de-ashing by Spencer Chemical in 1962. ° The aim was to produce a cleaned combustible fuel that was solid at room temperature. A 50-ton/day plant, located in Fort Lewis, Washington, operated in the SRC mode from its completion in October 1974 until it was modified in late 1976. It later was shut down in 1981. With this change came the new designation SRC-II, and the original process was sometimes designated as SRC-I. In 1972, another 6-ton/day pilot plant was built, in Wilsonville,... 

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