AKTIVERAD FLYTANDE KOKSKOMPOSITION SAMT SETT ATT FRAMSTELLA DENSAMMA

摘要

1440518 Activated fluid coke EXXON RESEARCH & ENG CO 22 June 1973 [28 June 1972 (3)] 29694/73 Headings C1A and C1C An activated fluid coke has a surface area of at least 400 m.2/gm. and a pore volume of 0À20 c.c./gm. The particle size of the coke is preferably in the range 50-600 microns. Coke may be activated by being heated in a fluidized bed with a gas containing steam at a temperature of at least 1500‹ F. for a period of time sufficient to convert at least 35 wt. per cent of the coke to gaseous products. The gas mixture used may contain at least 50 mole per cent of steam when an activated coke having the above stated properties is obtained. The period of activation may be at least 10 hours. The activation may be conducted at a pressure in the range 15 to 40 p.s.i.a. Before being contacted with steam the coke may be contacted with a free oxygencontaining gas stream at a temp. in the range 500‹ to 800‹ F., for a period of time so that the burn off of the initially present coke is maintained at less than 4% wt. an hour. The contacting with free oxygen containing gas and with steam may be performed in separate zones. The coke obtained may be used in removing suspended solids and organic contaminants from waste water. This may be accomplished by introducing an aqueous suspension of the fluid coke into the top of a vessel introducing waste water into the bottom of the vessel and countercurrently contacting the two and thereby removing contaminated coke from the bottom of the vessel and purified water from the top. The contaminated coke may be regenerated by separating from its accompanying water and then contacting with an oxidizing gas, e.g. air, at a temp. in the range 650- 800‹ F. If desired the waste water may be passed through a primary separation zone to remove a major portion of the suspended solids before contacting the activated coke.