Using Submerged Vibration Membrane System for Lignocelluloses Hydrolysate Filtration

In the 2^nd generation bioethanol production process, the low bio-ethanol concentration in fermentation broths results in a higher purification cost. A high bio-ethanol concentration can be achieved by different ways. The most direct way is by increasing the loading of the lignocellulose biomass [3, 4]. The two most important problems of high solid loadings are: a very high viscosity of the reaction mixture and the inhibitory effect of high concentrations [4-6]. To manage these problems, the bioreactor can be coupled to a membrane filtration process (membrane bioreactor, MBR). The fermentable sugars can be removed continuously while maintaining the enzymes in the bioreactor. However, challenges are recognized in practice, such as too low permeate sugar concentration (which is not helpful to increase ethanol yield in the fermentation step) and more pronounced membrane fouling at high substrate levels [7]

The recently developed magnetically induced membrane filtration (MMV) system was applied in a submerged configuration to filtrate a high substrate level lignocellulose hydrolysate using four different commercial ultrafiltration membranes to investigate the antifouling effect. The results indicated that membrane surface anti-fouling modifications could not really prevent fouling, while on the other hand, vibration enhanced filtration was proven to be an efficient way to improve membrane performance through prevention or reduction the foulant layer, especially at higher vibration amplitudes.

References:

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