CONTINUOUS METHOD FOR PROCESSING COAL TO PRODUCE STABLE SEMICOKE Russian patent published in 1997 - IPC

FIELD: coal conversion. SUBSTANCE: invention relates to favorable passivation and rehydration of reactive semicoke. Method includes following stages. Coal is pyrolyzed by way of gradually heating essentially all amount of coal to a temperature sufficient to evaporate and remove volatile components of low-boiling coal fraction to produce semicoke and mobilize some volatile components of high- boiling coke fraction. Combined effect of removal and mobilization of volatile components consists in partially destroying micropores in semicoke. Semicoke is then cooled to a temperature sufficient for immobilization and deposition of volatile components in partially destroyed micropores in order to pyrolytically passivate semicoke and produce one with volatile components of high-boiling fraction about 14-22 wt %. From the second stage, semicoke is transferred into reaction vessel, through which process gas with 3-21 vol.% of oxygen is passed at least partially fluidizing and oxidation-wise passivating coal because of chemisorption of oxygen. Finally, passivated semicoke is subjected to essentially simultaneous rehydration and cooling to yield stable semicoke with 5-10 (preferably 8) wt % moisture content. EFFECT: enhanced efficiency of process. 18 cl, 4 dwg