[Studies on harmful microbes in recirculating cooling water system of oil refinery].

The microbiol counts, type, distribution as well as interrelation between microbial counts and biofouling of the main harmful microbes including slimeforming heterotrophic bacteria, sulfate reducing bacteria, iron bacteria and fungi has been studies in 16 oil refineries of China. The control guideline of the harmful microbes for recirculating cooling water system of refinery were suggested, that is slime-forming bacteria less than 10(5)/ml, sulfate reducing bacteria less than 10(2)/ml. iron bacteria less than 10(3)/ml, fungi less than 10/ml. The appearing rate of the predominant strains from cooling water system of various refineries were calculated and identified and the composition of the main harmful representative microbes in cooling water system were determined.