SELECTION OF RO/NF MEMBRANES FOR WASTEWATER TREATMENT IN PRODUCTION OF VETERINARY PREPARATIONS

The efficiency of membrane wastewater treatment in the production of veterinary preparations whose primary goal is to remove antibiotics as the new kind of contaminants was tested. To this end, ten commercial composite reverse osmosis and nanofiltration membranes were selected. The membranes' porous characteristics, size and pore size distribution as well as flow's pressure-dependence were determined. By letting model solutions of antibiotic mixture through the RO/NF laboratory instrument, antibiotics separation was examined on the membranes of the characterized porous structure. The results showed that most tested membranes fully reject antibiotics from model waters. Three out of ten types of membranes were selected for further testing of the removal of antibiotics and other present substances from two wastewater equalization basins of Veterina d.d. Chromatographically, a presence of one antibiotic was determined in each equalization basin. The analysis of permeates for two membranes (XLE and NF90) showed maximum separation of the present antibiotic in wastewater, whereas slightly poorer but still satisfactory results were achieved with the HL membrane. From the presented chromatographs of feed, a presence of a whole series of unknown substances in equalization basins was observed, while from the chromatographs of permeates the success in their removal on individual membranes can be seen.