Brine Recovery System
Salt for the dyeing process is a major daily expense in the textile industry, especially for natural fabrics such as cotton. Besides the economic aspects concerning the money savings, environmental issues linked to excessively salty water discharges make water and salt reuse a priority for all the dyeing companies having strong environmental and sustainability policies. Our technology allows us to treat just the dye bath, which represents a small water amount as compared to the whole amount of water generated by the textile process. Moreover, the dye bath does not contain a significant concentration of hardness and therefore salt can be recovered without residual hardness.
Water coming from the dye bath is screened and filtered before the UF stage. Ceramic membranes are our choice for the UF section because they have a robust structure, resist temperature values of up to 130 °C, pH ranges between 0 and 14 and are almost impossible to foul thanks to wide passage channels and a high filtration velocity. The system efficiency allows for the removal of the suspended solids, as well as macromolecules and colloidal particles. Our UF membranes are designed according to our clients’specifics needs in order to guarantee maximum customization.
The NF section contains spiral polymeric membranes for textile industrial applications; these membranes show a high rejection of ions with +2 and -2 valence, such as Ca2+, Mg2+ and SO42-. while ions with +1/-1 valence like Na+, Cl- are able to pass with the permeate. Therefore, if in the dyeing process only NaCl is used, only this salt will be present in the permeate. The NF treatment line is able to recover up to 95 percent of the salt, while the remaining 5 percent of the water flow contains the rejected bivalent salts, color and impurities.