| 摘要 |
<p>Heavy hydrocarbon containing sludges (10) such as refinery waste streams, oil storage tank sludges and marine oil tanker ballast are treated by passing the sludges in a flow stream through an indirect dryer (12) to vaporize liquids having a boiling point at atmospheric pressure of less than about 700 DEG F and to provide substantially dried solid particles (22) discharged from the dryer. The dried particles, containing heavy hydrocarbons as a coating or as a part of the solids, are conducted to a combustor/oxidizer (62) and exposed to a high velocity flow stream of oxygen containing gas, typically low pressure forced air, to burn the residual hydrocarbons in the solids and to reduce heavy metals and the like to oxides thereof. A sludge handling system (9) includes a rotary disk type indirect dryer (12) connected to a lift pipe type combustor/oxidizer (62) for thorough exposure of the dried solids to an oxygen containing atmosphere. A centrifugal or cyclone type gas-solids separator (80)] receives the flow stream discharged from the lift pipe (64) and a portion of the dried solids (52) may be diverted after discharge from the dryer (12) back to the dryer inlet (18) to reduce the moisture content of the sludge flow stream introduced to the dryer (12) to minimize caking and clogging of the dryer (12) itself.</p> |
