1383988 Coke briquettes FMC CORP 14 Sept 1972 [15 Sept 1971] 42652/72 Heading C5E Coke briquettes are made from coal by (a) reacting coal particles with oxygen at above 250‹ F., shock heating the resulting particles to tardistilling temperatures to produce a char and a tar distillate, further heating the char to produce a calcinate having a non-condensible volatiles content of up to 3% and containing at least 1% hydrogen and cooling the calcinate; (b) treating the tar with oxygen to produce an oxygenated pitch; (c) briquetting the calcinate with the oxygenated pitch and heating the green briquettes in the presence of oxygen to induce an exothermic reaction and cure the briquettes; and (d) coking the cured briquettes at 1400- 1600‹ F. while recirculating the volatiles driven off and producing additional tar which is separately blown with air at a temperature above the boiling point of water to produce a pitch having a softening point above 120‹ F. and blending this pitch with the mixture to be briquetted in step (c). As shown cured briquettes from step (c) are heated in zone 12 of a kiln 10 by hot gases from the zone 14, the briquettes then pass through the hot zone 14 and through the cooling zone 16. Heat for the hot zone 14 is provided by a burner 18 fed with air 20, gas 22 and recycle gas 40. The volatiles from the heating are passed through a dry cyclone 28, a scrubber 30 and a wet cyclone 32 from which a tar 34 is recovered. The tar 34 is blown with air at 250-300‹ F. before being incorporated in the briquettes.
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