Estudo e avaliação de um sistema composto de membrana-resina para fins de produção de água de baixa condutividade elétrica.

Abstract

Whit the growing od good quality water, not only for human consumption, but also for some industrial applications, several purification technologies on water has been implemented successfully, such as desalination through reverse osmosis membranes, electrodialysis, thermal processes, ion exchange resins and others. The system aims the production of pure water, whit low electrical conductivity, which may be a research source for study and producing waters for hospital and pharmaceuticals purposes, etc... It is our understanding that these types of waters are very guarded by ANVISA and other federal agencies and their physico-chemical and biological properties are subject to change by the treatments to assess the quality of the product and the proper functioning of the system. From the parameters of pH and electrical conductivity, we observed a considerable decrease after regeneration of ion exchange resins within 30 to 80 minutes of operation. The pH varied from 6.2 to 4.2 and after 40 minutes the electrical conductivity became constant, reaching 0.8 uS.cm"1, indicating the regeneration. It can be observed in the present study a low salt rejection in a resin II column, to a pressure of 8.2 kgf.cm"2, reaching a maximum of 30% indicating a little efficiency of the reverse osmosis desalinization systems, unlike the other studied pressures (2.2 and 6.2 kgf.cm"2), where a rejection rate of 90% for most ions is observed.