US3923643A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Removal of lead and other suspended solids from used hydrocarbon lubricating oil
Assignee: Shell USA Inc
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Filing: 1974-06-14
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Granted: 1975-12-02
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Expires: 1994-06-14
Abstract
Abstract Lead and other dispersed solids present in used hydrocarbon lubricating oil which also contains water and light hydrocarbon impurities are removed by a process wherein agglomeration of the suspended lead and other solids is induced by heat treatment of the used oil at about 500 to 700*F after flashing off the water and light hydrocarbon material. The agglomerated solids are readily separated from the heat treated oil by conventional physical separation techniques such as centrifuging or gravity settling to afford a used oil substantially free, i.e., at least 90% lead removal, of lead and other solid contaminants.
Inventors
- 👤 Robert W Lewis
- 👤 Thomas A Rodgers
- 👤 Jr Charles F Goeking
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 21:28
CPC Classifications
C; C10; C10M; C10M175/00; C10M175/0025
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
146 words
A PROCESS FOR REMOVING SUSPENDED LEAD AND OTHER DISPERSED SOLIDS FROM USED HYDROCARBON LUBRICATING OIL WHICH COMPRISES: A. HEATING THE USED HYDROCARBON LUBRICATING OIL UNDER TEMPERATURE AND PRESSURE CONDITIONS AT WHICH SUBSTANTIALLY ALL THE WATER AND VOLATILE HYDROCARBON MATERIALS BOILING BELOW ABOUT 500*F AT ATMOSPHERIC PRESSURE WILL VOLATILIZE OUT OF THE USE OIL IN A DEVOLATILIZATION ZONE TO AFFORD A USED HYDROCARBON LUBRICATING OIL SUBSTANTIALLY FREE OF WATER AND SAID VOLATILE HYDROCARBONS, SAID WATER AND VOLATILE HYDROCARBONS BEING REMOVED AS A GASEOUS OVERHEAD, B. SUBJECTING THE USED HYDROCARBON LUBRICATING OIL SUBSTANTIALLY FREE OF SAID WATER AND VOLTILE HYDROCARBONS TO FURHER HEAT TREATMENT AT A TEMPERATURE BETWEEN ABOUT 500* AND 700*F FOR ABOUT 1 TO 12 HOURS IN A HEAT TREATMENT ZONE THEREBY AGGLOMERATING THE LEAD AND OTHER DISPERSED SOLIDS CONTAINED IN THE USED OIL AND C. SEPARATING THE AGGLOMERATED SOLIDS FROM THE USED HYDROCARBON LUBRICATING OIL.
Claim 2
Dependent Claim
146 words
A PROCESS FOR REMOVING SUSPENDED LEAD AND OTHER DISPERSED SOLIDS FROM USED HYDROCARBON LUBRICATING OIL WHICH COMPRISES: A. HEATING THE USED HYDROCARBON LUBRICATING OIL UNDER TEMPERATURE AND PRESSURE CONDITIONS AT WHICH SUBSTANTIALLY ALL THE WATER AND VOLATILE HYDROCARBON MATERIALS BOILING BELOW ABOUT 500*F AT ATMOSPHERIC PRESSURE WILL VOLATILIZE OUT OF THE USE OIL IN A DEVOLATILIZATION ZONE TO AFFORD A USED HYDROCARBON LUBRICATING OIL SUBSTANTIALLY FREE OF WATER AND SAID VOLATILE HYDROCARBONS, SAID WATER AND VOLATILE HYDROCARBONS BEING REMOVED AS A GASEOUS OVERHEAD, B. SUBJECTING THE USED HYDROCARBON LUBRICATING OIL SUBSTANTIALLY FREE OF SAID WATER AND VOLTILE HYDROCARBONS TO FURHER HEAT TREATMENT AT A TEMPERATURE BETWEEN ABOUT 500* AND 700*F FOR ABOUT 1 TO 12 HOURS IN A HEAT TREATMENT ZONE THEREBY AGGLOMERATING THE LEAD AND OTHER DISPERSED SOLIDS CONTAINED IN THE USED OIL AND C. SEPARATING THE AGGLOMERATED SOLIDS FROM THE USED HYDROCARBON LUBRICATING OIL.
Claim 3
Dependent Claim
27 words
The process according to claim 1 wherein the separation of agglomerated solids from the used hydrocarbon lubricating oil is effected in one or more gravity settling zones.
Claim 4
Dependent Claim
46 words
The process according to claim 1 wherein the heat treatment step and the agglomerated solids separation step are carried out in a single processing step in one or more gravity settling zones wherein the lead and other dispersed solids are allowed to settle as they agglomerate.
Claim 5
Dependent Claim
87 words
The process according to claim 1 whErein the volatilization of water and volatile hydrocarbons contained in the used hydrocarbon lubricating oil is effected continuously by recycling a portion of the used hydrocarbon lubricating oil substantially free of water and volatile hydrocarbons from the devolatilization zone through a separate used oil heating zone and continuously introducing fresh used hydrocarbon lubricating oil feedstock into this recycle line at a point subsequent to the used oil heating zone but prior to recycle of the used oil into the devolatilization zone.
Claim 6
Dependent Claim
99 words
The process according to claim 4 wherein the agglomeration of the lead and other dispersed solids and at least partial separation of said agglomerated solids are effected continuously by passing the used oil substantially free of water and volatile hydrocarbons into a heat treatment zone comprising at least two gravity separation zones operated in parallel, one separation zone being filled with said used oil while the other separation zone filled with said used oil is utilized to effect the heat treatment for the time required to substantially agglomerate and at least partially separate the lead and other dispersed solids.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-12-01 | 1979-06-02 | 1979-12-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-12-01 | 1983-06-02 | 1983-12-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-12-01 | 1987-06-02 | 1987-12-02 | $7700.00 | Window Closed / Lapsed |