A preliminary comparison between nanofiltration and reverse osmosis membranes for grape juice treatment

• Published in: Journal of food engineering Vol. 50; no. 2; pp. 113 - 116
• Main Authors: Ferrarini, Roberto, Versari, Andrea, Galassi, Sergio
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.11.2001; Elsevier
• Subjects: Biological and medical sciences; Food engineering; Food industries; Fruit and vegetable industries; Fundamental and applied biological sciences. Psychology; General aspects; Grape juice; Nanofiltration; Pressure; Reverse osmosis; Temperature; Nanofiltration; Temperature; Reverse osmosis; Grape juice; Pressure; Fouling; Fruit; Grape; Selectivity; Permeability; Fruit juice; Comparative study
• ISSN: 0260-8774; 1873-5770
• DOI: 10.1016/S0260-8774(00)00199-0

Nanofiltration (NF) and reverse osmosis (RO) systems were compared using grape juice as feed solution. The initial permeate flux ( J) was 7.4, 8.1, and 1.7 dm 3 m −2 h −1 with NF membranes DS and DK, and RO membrane SWC, respectively. The exponential decay of J in the above NF and RO membranes was characterized by a fouling index equal to 0.16, 0.22, and 0.24, respectively. The permeability of NF membrane DS doubled by increasing the working pressure from 32 to 45 bar. Despite the additional power (+30%) required to work at the higher pressure value there was an energy saving per unit permeate of approximately 35%. The working pressure and temperature affected the selectivity of NF membranes. As expected, a direct relationship between membrane permeability and working temperature occurred; the permeate flux of NF membrane DS increased by about 3% per degree of temperature rise.