Click for next page ( 189


The National Academies | 500 Fifth St. N.W. | Washington, D.C. 20001
Copyright © National Academy of Sciences. All rights reserved.
Terms of Use and Privacy Statement



Below are the first 10 and last 10 pages of uncorrected machine-read text (when available) of this chapter, followed by the top 30 algorithmically extracted key phrases from the chapter as a whole.
Intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text on the opening pages of each chapter. Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.

Do not use for reproduction, copying, pasting, or reading; exclusively for search engines.

OCR for page 188
H Coprocessing Technology Signal-UOP coprocessing technology (Luebke and Humbach, 1987) has its origins in resid upgrading and differs from most of the other processes in that it is a single-stage entrained-catalyst system. In the process (Figure H- 1) hydrogen, coal, petroleum resid, and catalyst are fed to a single-stage conversion reactor. After separation of the distillate products, the vacuum resid is processed to recovery catalyst for recycle. The process has been tested with bituminous and subbituminous coals. It operated well and gave resid conversions of about 55 percent. The UOP process is designed to be integrated into an existing refinery with the capability to handle the remain- ing resid from the coprocessing unit. Therefore, the conversion level re- ported above is acceptable in commercial operation. Depending on the ease of catalyst recovery, the UOP process is characterized by a simple flow sheet. The requirement of refinery integration may not be a severe limita- tion, because the predominant application of coprocessing is expected to be in retrofit situations. HRI coprocessing technology provides a clear link between laboratory and pilot plant development and possible near-term commercialization. The HRI two-stage coprocessing technology grew out of the COIL process, much as HRI two-stage liquefaction technology developed from the H-coal proc- ess. Each is based on the commercial H-oil process for heavy resid upgrad- ing. The H-oil process and similar expanded bed hydrotreaters are in com- mercial use in the United States, Canada, Mexico, and Kuwait. The HRI coprocessing scheme (Figure H-2) feeds a coal-oil slurry to two expanded bed catalytic reactors in series. The use of a recycle stream is optional, depending on the feed coal-to-resid ratio. HRI has processed coals from lignite to high-volatile A bituminous (ruddy et al., 1989), achieving high conversions (greater than 90 percent at 975F+), 188

OCR for page 188
APPENDIX H COAL ~ RESID- ~ . CATALYST: 189 100 , l CATALYST RECYCLE AF = ATMOSPHERIC FRACTIONATOR R= REACTOR S= SEPARATOR VF = VACUUM FRACTIONATOR ~ H2 H2O' H2S' NH3 LIGHT GASSES LIGHT OIL VGO REFINERY CONVERSION . UNIT FEED Lo CAT. I REC. _ OIL UNCONVERTED COAL, ASH, RESIDUE FIGURE H-1 Signal/UOP's proposed residlcoal processing scheme. SOURCE: Luebke and Humbach (1987~. RECYCLE HYDROGEN ~ , HYDROGEN ~ l ~ FIRST-STAGE f CATALYTIC REACTOR T HYDROGEN HEATER _ ~ SLAY MIX ~ IRY | HEATER SECO~STAGE CATALYTIC REACTOR RECYCLE SLURRY OIL I ~ IBP-350F 350-500F _500-750f '_750-975F ~VPSJ l l I L, VACUUM I BOTTONIS 1 ~ _ FIGURE H-2 Simplified flow plan for HRI's two-stage process. SOURCE: Duddy et al. (1986~.

OCR for page 188
190 APPENDIX H desulfurization (86 percent), denitrogenation (80 percent), and demetalla- tion (99 percent). Because of the high conversions, HRI coprocessing tech- nology could be considered for either retrofit to an existing refinery or for a stand-alone grass-roots facility. The argument that this technology could be commercialized within the 5-year study time frame is based on the commer- cial status of the expanded bed technology and the successful operation of the H-coal pilot plant in Cattletsburg, Kentucky, in the early 1980s. This pilot plant operated at 500 tons/day of coal and produced about lSOO bbl/ day of liquids with the process configuration used. This operation demon- strated various critical components, such as slurry pumps and let-down valves, for use with coal on a precommercial scale.