Patent · US Expired

Agitated heat exchanger to chill solvent-oil and wax slurry to wax filtration temperature

US4502787A · kind A · utility

8Cited by
19References
6Claims
0Family size

Assignee

Inventor

Key dates

Filing dateDec 5, 1983
Grant dateMar 5, 1985
Priority date
Expiry dateDec 5, 2003

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC10G73/06
  • WIPO fieldBasic materials chemistry
  • WIPO sectorChemistry

Abstract

An improved process for dewaxing waxy hydrocarbon oils, wherein said waxy oil is introduced at a temperature above its cloud point into a direct chilling zone divided into a plurality of stages, passing said waxy oil from stage-to-stage of said chilling zone, introducing a cold dewaxing solvent into at least a portion of said stages, maintaining a high degree of agitation in at least a portion of the stages containing solvent and waxy oil, thereby effecting substantially instantaneous mixing thereof while cooling said solvent-waxy oil mixture, preferably at a rate of from about 1.degree. to 8.degree. F./min., as it progresses through said direct chilling zone to a temperature greater than the wax separation temperature, whereby a substantial portion of the wax is precipitated from said waxy oil under conditions of said high degree of agitation and forming a solvent-oil mixture containing precipitated wax (slurry I), withdrawing said slurry I from said direct chilling zone and cooling same to the wax separation temperature in an indirect chilling zone thereby precipitating a further portion of wax from said waxy oil and separating said precipitated wax from the wax-oil-solvent mixtu…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.