Scale-up of the Solid−Liquid Extraction Using Characteristic Function Technique

• Published in: Industrial & engineering chemistry research Vol. 43; no. 16; pp. 4903 - 4907
• Main Authors: Simeonov, E, Seikova, I, Pentchev, I, Mintchev, A
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 04.08.2004
• Subjects: Applied sciences; Chemical engineering; Exact sciences and technology; Characteristic function; Extrapolation; Scale effect
• ISSN: 0888-5885; 1520-5045
• DOI: 10.1021/ie030650m

A scale-up methodology based on the characteristic function approximation for the mass-transfer rate is proposed that provides a reliable and inexpensive method for designing and controlling an extraction apparatus. The characteristic function is derived in terms of the usual kinetic and equilibrium parameters. An analytical expression for the overall resistance to mass transfer is also obtained, providing a linearly variable mass-transfer resistance during the extraction. Experimental data for the kinetics of extraction in a laboratory-scale batch extractor from four solid−liquid systems are presented and discussed in relation to the theory. The calculation procedure is applied to estimate the extraction times in a continuous-action apparatus corresponding to an assigned extraction yield. The calculation results are also supported by experiments in a pilot screw extractor.