GB1494162A - Method for reclaiming used active carbon - Google Patents

Abstract

1494162 Reclamation of active carbon TAIYO KAKEN CO Ltd 21 April 1976 [21 April 1975] 16212/76 Heading C1A Used particles of active carbon are reclaimed by passing an electric current through the carbon particles so as to heat them, the electric current being passed through the carbon particles in a reclaiming zone manitained filled with the carbon particles and through which the particles progressively move in a direction generally parallel to the flow of electric current, and wherein a gas is blown through the carbon particles in a direction countercurrent to the direction of movement thereof, to remove gases desorbed from the surfaces of the particles in the reclaiming zone. The reclaiming zone is suitably a substantially vertical column through which the particles (which are preferably spherical) move with the aid of gravity; preferably the upper and lower ends of the zone are defined by a generally horizontal electrode plate having a plurality of openings therethrough of a size to permit the carbon particles to pass therethrough to enter or leave the reclaiming zone, the electric current being applied between the electrode plates. At least 25% of the surface area of the plate, desirably at least 40%, may be represented by said openings. The heat-treatment may be carried out in two stages, a pre-heating stage followed by a desorption stage. Where several kinds of materials having different desorption temperatures are adsorbed on the carbon particles, the contaminants may be separately desorbed and recovered by appropriately controlling the voltage applied to a plurality of pairs of electrode plates arranged to form several reclaiming zones in series.