Electro-ultrafiltration of amylase enzymes: Process design and economy

Electro-ultrafiltration (EUF) has previously resulted in flux improvements in the order of 3–7 times during filtration of amylase enzymes [Enevoldsen, A.D., Hansen, E.B., Jonsson, G., 2007. Electro-ultrafiltration of industrial enzyme solutions. Journal of Membrane Science 299, 28–37]. To determine the energy balance for EUF, the influence of TMP, crossflow velocity and conductivity of the enzyme solution is studied and compared to conventional ultrafiltration (UF). EUF is favorable when filtering solutions of high concentration, while UF is favorable when filtering solutions of low concentration. The dimension of the feed channel, especially the height and the conductivity are crucial for the feasibility of the EUF process. The channel height should be below 1.0 mm and the conductivity less that 2 mS/cm before EUF is economically feasible.