Treatment of petroleum cokes with a puffing inhibitor in a rotary calciner

摘要

A rotary hearth calciner for treating petroleum cokes with a puffing inhibitor has a horizontal or inwardly sloping hearth floor rotatable around a vertical axis for receiving particles of coke to be calcined and a central opening in the hearth floor for discharging the coke into a soaking pit. A water cooled, refractory covered feed pipe extending downward into the calciner interior has an inlet for connection to a source of petroleum coke puffing inhibitor and an outlet near the edge of the hearth central floor opening for adding the puffing inhibitor to the coke as the coke is discharged from said hearth floor. The feed pipe outlet is approximately at or below the level of the hearth floor to reduce loss of inhibitor in gas flow above the hearth floor. A puffing inhibitor such as sodium carbonate is supplied by a screw feed mechanism to the feed pipe to add the puffing inhibitor at a desired rate for reaction with the coke. The coke is normally maintained in the soaking pit for about 30 minutes at 1200 DEG -1400 DEG C.