The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 15, 1982
Filed:
Nov. 24, 1980
Thomas E Broadhurst, Sarnia, CA;
Exxon Research & Engineering Co., Florham Park, NJ (US);
Abstract
In hydrocarbon oil dewaxing processes comprising passing the waxy oil through a staged vertical tower, injecting cold solvent at a plurality of stages along the vertical tower under conditions of high agitation to achieve substantially instantaneous mixing at each point, continuing the chilling, preferably at a rate of from 1.degree. to 8.degree. F. per minute, by means of cold solvent injection until a temperature at least 30.degree. F. above the filtering temperature but less than about 40.degree. to 45.degree. F. above the filtering temperature is reached and completing the cooling of the oil to the separation temperature in rotating element scraped surface chillers, the improvement comprising operating the scraped surface chillers at a chilling temperature range of at least 30.degree. F. while reducing the operating speed of the rotating elements in the scraped surface chiller to a speed of from 5 to 20% preferably 8 to 14% of the original design operation speed. Operation at this reduced speed improves wax separation rates by about 10 to 20% while not adversely effecting the heat transfer performance of the chillers.