Method for on-line monitoring of wax crystallization
AssigneeExxonMobil Research and Engineering Company
InventorsThomas R. Palmer, Brent E. Beasley, David S. Sinclair
Life of this patent
Estimating the term…
Abstract
The determination of wax crystal particle size and population is used to monitor the performance of wax crystallizers used in lubricant oil processing using solvent dewaxing. The wax crystal particle size is monitored using online measurements. The information obtained from on-line monitoring is then used to control crystallization in the dewaxing equipment in order to optimize performance of the dewaxing units.
Claims21
A process for on-line monitoring of wax crystal formation in solvent dewaxing equipment for use in lubricant oil production, said solvent dewaxing equipment including at least one chilling tower, which comprises:
- conducting a waxy feedstock to the at least one chilling tower having at least one inlet and outlet, contacting the waxy feedstock with chilled dewaxing solvent to form a mixture of solvent, oil and wax crystals, conducting the mixture from the at least one chilling tower outlet to a separator provided that wax crystal size distribution of the wax crystals in the mixture is measured prior to entering the separator using an on-line particle size analyzer, and separating wax crystals from oil and solvent.
A solvent dewaxing process for the preparation of lubricant oils from a waxy feedstock which comprises:
- conducting the waxy feedstock to at least one chilling tower having at least one inlet and outlet, contacting the waxy feedstock with dewaxing solvent in at least one chilling zone in the chilling tower under mixing conditions to form a mixture of wax crystals, solvent and oil, conducting the mixture from the at least one chilling tower outlet to a separator provided that wax crystal size distribution of the wax crystals in the mixture is measured prior to entering the separator using an on-line particle size analyzer, separating wax crystals from oil and solvent, and adjusting conditions as needed in the at least one chilling tower to modify wax crystal size to improve separation of wax crystals.
Dependencies are inferred from the claim text.