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Combined technology electrodialysis - nuclear desalination for liquid water solutions treatment Dr B. Pilat Eikos Co. Ltd. (Russia) It goes without saying that civilization development is the irreversible process. However using its benefits we pay little attention to the expenses that being ignored would influence the prosperity of many regions. Liquid wastes or solutions with radioactive substances appear both as systematic and inevitable factor and as the result of the ill-considered human activity. Solutions get in laboratories, leakage from nuclear stations, etc can be considered the first group. Water solutions formed spontaneously as the result of nuclear disaster and nuclear weapons tests can be considered the second group: Chernobl (Ukraine), the Urals (Russia), Semipalatinsk (Kazakhstan). Ions� migration in the soil with radioactive charge inclusive, does not take place as united front but get specific configuration of � tongues� under the influence of peculiarities of configuration of terrain and soil condition. Well contouring of such grounds or fields allows to find out the places with abnormal high concentration of radioactive matter and in some cases to highlight and group these flows with the help of special engineer facilities with the aim of their further treatment. Practical issues of their concentration are of the most interest taking into consideration those real technologies that are available now. Only three industrial ways of solution concentration and treatment exis: reverse osmosis; electrodialysis; various evaporation technologies (nuclear inclusive). RO does not fit for concentration due to impossibility to reduce radically the concentrate�s volume over the standard 30 %. Electrodialysis proved itself beautiful for concentration in industrial application. In particular in Japan the whole amount of food salt is received from the ocean by solutions� concentration to 120-150 g/l followed by evaporation. Thus the combined technological scheme is the ideal one, when at the first stage radioactive water solutions are subjected to electrodialysis getting fresh diluted not radioactive water and concentrate that is to be evaporated at the second stage. Even from general view it is clear that this scheme is very economical. TDS in natural water varies in the range of 120-1200 mg/l. At the first stage the result of electrodialysis is the solution, with TDS to 1,2 mg/l. Thus radioactive matter concentration decreases by 100-1000 times. Concentrate with more than 120 mg/l salts is directed to nuclear concentration, and it is clear that in this case the solution volume subjected to evaporation can be reduced by 1000 times. Special methods of electrodialysis allow get solutions heated to 70-90 degrees C and that increases the process efficiency even more. The most well known part of this technology is electrodialysis, however the progress developed in the last years in many countries allows to use electrodialysis systems completely automatic without men interference for a long time.