Electrodialysis cell added

A volume of wine is pumped into the treatment vat and then into the diluate circuit of the electrodialysis cells. When conductivity reaches the set point, determined by an instability test, the wine is automatically pumped into a reception vat using a system controlled by solenoid valves. A new volume of wine is then pumped into the system and stabilized under the same conditions. Treatment time and, consequently, the performance of the system depend on the wine s degree of instability. Treatment flow rates vary from 50 to 150 1/h/m, depending on this parameter. The concentrate circuit consists of a saline solution that collects the ions extracted from the wine. The ion load is adjusted by adding water to avoid the precipitation of bitartrate crystals inside the small, easily blocked cells. This function is also automatically controlled by conductivity measurements. 

The other bottleneck for lactic acid production is the operating cost. For example, sterilization is necessary for fermentative production. Hence, microorganisms have an optimal fermentation temperature between 30 2°C (John et al., 2007). Therefore it is difficult to avoid contamination if the medium is not sterilized. Qin et al. (2009) have reported the use of a newly isolated thermophilic strain. Bacillus sp. strain 2 to 6, for the unsterilized fermentative production of L-lactic acid. A high yield (97.3%), productivity (4.37g/L/h), and optical purity of L-lactic acid (99.4%) were obtained in batch and fed-batch open fermentations (Qin et al., 2009). This will help to reduce energy consumption and lower labor costs. Moreover, because of the inhibitory effects of a low pH on cell growth and lactic acid production, CaCOs must be added to maintain a constant pH as a consequence, the regeneration of precipitated calcium lactate is observed (Datta and Henry, 2006). To solve this problem, a sodium lactate-tolerant strain. Bacillus sp. Na-2, was obtained by ion-beam implantation and applied during an L-lactic acid production process (Qin et al., 2010). On the other hand, new processes can be applied to prevent the production of calcium lactate, for example, reverse osmosis, ultrafiltration, electrodialysis, and solvent extraction (Datta and Henry, 2006). 

---