| abstract |
The present invention concerns a process for producing water enriched with natural orthosilicic acid, said process comprising at least the following successive steps: a. a step of reverse osmosis of a raw water containing a low amount of orthosilicic acid in order to obtain a retentate; b. a step of electrodialysis of the retentate obtained in step a) with an electrodialysis stack comprising alternating pairs of cation selective membranes and anion selective membranes, said cation selective membranes and anion selective membranes being selected in the group of monovalent selective membranes and standard grade membranes such that the stack contains at least one cation standard grade membrane, one cation monovalent selective membrane, one anion standard grade membrane and one anion monovalent selective membrane; c. a step of recovery of a final water having a orthosilicic acid weight content equal to at least 150%, particularly at least 200%, more particularly at least 300% of the orthosilicic acid weight content of the raw water, and a dissolved valuable mineral ions weight content comprised in the range of 70 to 130%, particularly in the range of 80 to 120%, more particularly in the range of 90 to 110 % of the dissolved valuable mineral ions weight content of the raw water. It concerns also the still drinking water obtainable by the process and its uses. |