An UF continuous recycled system was operated for 80 hours
with sterile effluents (two types) primarly inoculated with three bacterial
species: Pseudomonas aeruginosa, Acinetobacter johnsonii and Bacillus
subtilis (separately and combined) and supplemented with their
corresponding bacteriophages (phages) versus control (bacteria without phages).
The lytic activity of these phages reduced membrane biofouling by an average
of 40 to > 60 % compared to control (bacteria only). Phage numbers
increased in the concentrate and some were found in the permeate, however no
bacteria were found in the permeate. Combinations of one, two and three
bacterial species and their specific phages revealed very good inactivation
rates as well reduced biofouling as observed under high resolution electron scaninng
microscope (HSEM). The advantage of phage utilization in combating biofouling
in such system as UF was demonstrated, pointing towards future application in
other membrane processes such as: nanofiltration and reverse osmosis.