Flash hydropyrolysis of coal. Quarterly report No. 11, October 1-December 31, 1979

The following conclusions can be drawn from this work: (1) when the caking bituminous coals are used with diluents, only 20% Pittsburgh No. 8 coal can be added to the diluent swhile 40% Illinois No. 6 could be added due to the higher free swelling index of the Pittsburgh No. 8; (2) When limestone is used as a diluent, considerably more sulfur is retained in the char than when using sand; (3) when the char from an experiment using limestone is recycled as the diluent for another experiment, the char continually retains additional sulfur through at least three recycles; (4) decomposition of the limestone and reduction is indicated by the high concentrations of CO observed at 900/sup 0/C; (5) increasing the coal feed rate by a factor of 4 from 2.4 to 10.7 lb/hr at low H/sub 2//Coal ratios (approx. = 0.6) results in no appreciable change in gaseous HC yields (approx. = 27%) or concentration (approx. = 45%) but higher BTX yields (1.1% vs. 5.4%); (6) although only one experiment was conducted, it appears that hydrogasification of untreated New Mexico sub-bituminous coal at 950/sup 0/C does not give an increase in yield over hydrogasification at 900/sup 0/C; (7) the hydrogasification of Wyodak lignite gives approximately the same gaseous HC yields as that obtained from North Dakota lignite but higher BTX yields particularly at 900/sup 0/C and 1000 psi (9% vs. 2%); (8) treating New Mexico sub-bituminous coal with NaCO/sub 3/ does not increase its hydrogasification qualities between 600/sup 0/C and 900/sup 0/C at 1000 psi but does decrease the BTX yield