The use of conventional methods for industrial purification and concentration of waste water are not always effective. The evaporation and reverse osmosis which are applying in this purpose may generate high costs. An alternative may be the use of cryoconcentration. In the paper the physical background of the process and the possibility of practical application of freezing to industrial purification and concentrating of waste water were presented. The Niro GEA methods and the methods of direct water crystallization in tubular and drum heat exchangers were detailed discussed. It has been found that the purification of waste water when use of freezing technology is characterized by many economical as well as practical advantages. It was also indicated that the use of natural weather conditions in the winter could be a breakthrough into wider application of freeze concentrating for the purification of sewage in Poland.

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