Separation Science and Technology, Vol.34, No.9, 1859-1872, 1999
Oldshue-Rushton column in supercritical fluid extraction
The performance of a mechanically agitated Oldshue-Rushton column using carbon dioxide solvent at 10 MPa and 313 K to extract ethanol from aqueous feed was investigated. The overall mass-transfer coefficient K(od)a, the height equivalent to a theoretical stage (HETS), dispersed phase holdup, as well as the column capacity data were measured as a function of solvent-to-feed ratio and rotor speed. The values of overall mass transfer coefficient K,da generally ranged from 0.009 to 0.012 s(-1), and the values of the HETS ranged from 0.44 to 0.74 m. The total throughput of the Oldshue-Rushton column without agitation was approximately 68 m(3).h(-1).m(-2), whereas at 300 rpm the total throughput was approximately 48 m(3).h(-1).m(-2).