Used lubricating oil reclaiming
AssigneeTexaco Inc.
InventorsCharles W. Harrison, Arthur G. Gorneau, Robert M. Steinberg, Bruce R. Bond
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Abstract
A used lubricating oil comprising lube oil additives, including zinc dithiophosphate is subjected to reclaiming. 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) distillate oil is useful as marine diesel fuel. 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.
Claims15
A process for reclaiming used lubricating oil comprising organometallic compounds including zinc dithiophosphate in a concentration of 0.01 to 5.0 wt %, comprising:
- heating the used lubricating oil to an additive decomposition temperature of about 400.degree. F. (204.degree. C.) to 1000.degree. F. (523.degree. C.), and
- maintaining the additive decomposition temperature for a residence time in the range of 10 to 120 minutes, thereby reducing the zinc dithiophosphate concentration to 0.001 wt % or less in the absence of chemical demetallizing.
A process for reclaiming used lubricating oil having a zinc dithiophosphate concentration of 0.01 to 2.0 wt %, comprising the steps of:
- (a) maintaining the used lubricating oil at an additive decomposition temperature of about 400.degree. F. (204.degree. C.) to 1000.degree. F. (538.degree. C.) for a residence time in the range of about 10 to 120 minutes;
- (b) vacuum distilling at a distillation temperature of 400.degree. F. (204.degree. C.) to 1050.degree. F. (565.degree. C.) and a distillation pressure of 20 to 500 mm Hg,
- (c) recovering a distillate product comprising 0.001 wt % or less zinc dithiophosphate, and an asphaltic bottoms product comprising zinc containing degradation products.
A process for reclaiming used lubricating oil comprising organometallic compounds including zinc dithiophosphate in a concentration of 0.01 to 5.0 wt %, comprising:
- (a) heating the used lubricating oil by means of direct heat exchange by admixing with a heated product oil to form an admixture, said heated product oil at an additive decomposition temperature of about 400.degree. F. (204.degree. C.) to 1000.degree. F. (523.degree. C.),
- (b) maintaining the admixture at the additive decomposition temperature for a residence time in the range of 10 to 120 minutes, thereby reducing the zinc dithiophosphate concentration to 0.001 wt % or less to form a product oil, and
- (c) heating the product oil to a temperature of 400.degree. F. (204.degree. C.) to 1000.degree. F. (523.degree. C.) by means of indirect heat exchange to yield the heated product oil.
A process for reclaiming used lubricating oil having a zinc dithiophosphate concentration of 0.01 to 5.0 wt %, comprising the steps of:
- (a) heating the used lubricating oil by direct heat exchange by means of admixing with a heated product oil at an additive decomposition temperature of about 400.degree. F. (204.degree. C.) to 1000.degree. F. (538.degree. C.) and maintaining a residence time in the range of about 10 to 120 minutes to yield a product oil comprising 0.001 wt % or less zinc dithiophosphate;
- (b) heating the product oil by means of indirect heat exchange to the additive decomposition temperature of 400.degree. F. (204.degree. C.) to 1000.degree. F. (538.degree. C.) to produce the heated product oil.
- (c) vacuum distilling the heated product oil at a distillation temperature of 400.degree. F. (204.degree. C.) to 1050.degree. F. (565.degree. C.) and a distillation pressure of 20 to 500 mm Hg, and
- (d) recovering a distillate product comprising 0.001 wt % or less zinc dithiophosphate, and an asphaltic bottoms product comprising zinc containing degradation products.
Dependencies are inferred from the claim text.