A used lubricating oil comprising lube oil additives, including zinc dithiophosphate is reconstituted. Zinc dithiophosphate is thermally decomposed at a temperature of 400.degree. F. (204.degree. C.) to 1000.degree. F. (538.degree. C.) for a residence time of 10 to 120 minutes. The resulting oil is subjected to vacuum distillation. A zinc-free (i.e. ash free by ASTM D-482) oil is stabilized by catalytic hydrogenation or clay treating to produce a lubricating oil blending stock. About 5 to 25 vol % is recovered as a metal containing bottoms product, useful as asphalt extender. The process is carried out in the absence of chemical demetallizing.
Used Motor Oil is re-refined by direct injection of a superheated, non-hydrogenating recycle vapor. The process operates at low pressures, preferably from atmospheric--10 atmospheres absolute. Preferably a significant amount of the energy required to vapor used motor oil is supplied in the form of increased sensible heat of a recycle vapor stream. Direct injection of superheated vapor reduces or eliminates fouling which can occur when indirect heat exchange is used to supply the heat needed to vaporize used motor oil.
A continuous, hot vapor injection process and apparatus is provided for recovering lube oil base stocks from used lubricating oil containing distillable liquid hydrocarbons and water. Also disclosed is an asphalt blend composition containing an asphalt component and the bottoms from the above process.
An asphalt blend composition containing an asphalt component and a bottoms fraction from a used motor vaporization process of the above process, and a pavement composition comprising aggregate and the asphalt blend composition. The process comprises directly contacting used lubricating oil with a heated vapor, e.g., steam, under conditions which at least partially decompose the organo-metallic component and provide a desired volume of pumpable bottoms containing organo-metallic compound decomposition products and an overhead comprising gases and distillatable hydrocarbons, with no substantial carryover of metals into the overhead. The process may be carried out under conditions which minimize decomposition of high molecular weight additives such as VI improvers.
A process for the direct contact heating and vaporization of UMO is disclosed. A superheated, but condensable, vapor heats and vaporizes distillable liquid hydrocarbons from a waste motor oil stream, producing an overhead vapor fraction of injected superheated vapor and vaporized boiling range components. This material is cooled and partially condensed to produce lube boiling range liquid hydrocarbons and a vapor phase, which is condensed to produce a recycle liquid phase. Recycle liquid is pumped and then heated to produce superheated vapor for recycle to contact the UMO.
A process is provided for recovering lube oil base stocks from used lubricating oil formulations containing base oil stock and organo-metallic component which obviates preseparation of water and light hydrocarbons contaminants. The process comprises directly contacting used lubricating oil with a heated vapor, e.g., steam, under conditions which at least partially decompose the organo-metallic component and provide a desired volume of pumpable bottoms containing organo-metallic compound decomposition products and an overhead comprising gases and distillatable hydrocarbons, with no substantial carryover of metals into the overhead. The process may be carried out under conditions which minimize decomposition of high molecular weight additives such as VI improvers, to provide a bottoms fraction which may be added to asphalt or fuel oil. Also disclosed are an asphalt blend composition containing an asphalt component and the bottoms of the above process, and a pavement composition comprising aggregate and the asphalt blend composition.
