| 摘要 |
<p>1324054 Activated carbon PEABODY COAL CO 9 Sept 1971 [2 April 1971] 42156/71 Heading C1A [Also in Division C5] Activated carbon is made in an apparatus comprising a horizontally moving grate and a vertical shaft, similar to the apparatus described in Specification No. 1,181,647. At least three air boxes are located serially along and beneath the grate, air and steam being delivered upwardly through a bed of carbonaceous material, e.g., lignite, on the grate, from the two boxes nearest the output end of the apparatus, and hot gases (N 2 , CO, CO 2 , O 2 ) being drawn downwardly through the bed into the first box. The air and steam supply is controlled to cause limited combustion of the lignite sufficient to raise the bed temperature over the middle box to initiate the water gas reaction, i.e., to above 1830‹ F., and the lignite passing over the last box is quenched with steam, optionally with water, to a temperature below 1470‹ F. to initiate the reaction C + 2H 2 O = CO 2 + 2H 2 . The quenched lignite is then cooled with steam in the shaft in the absence of air and passed through a tumbler to a screen which separates coke and ash from the required activated char. The down-drawn gases may be sent to atmosphere through a scrubber or may be injected into the apparatus near the outlet end and sent to atmosphere through a waste heat boiler, see Fig. 2, (not shown).</p> |
