Study of the Biofouling Problems in the Recirculating Cooling Water System of a Petroleum Refinery Plant

摘要

Monitoring and field studies of the biofouling problems in a recirculating cooling water system (RCWS) of the Bulgarian Petroleum Refinery Plant, Plama Ltd. were carried out. Chemical and microbiological characteristics of the biofilms developed on different surfaces in contact with the cooling water (heat exchanger surfaces, carbon steel and stainless steel biofilm collector coupons) were made. The microbial compositions of the biofilm consortia formed on the heat exchanger surfaces and biofilm collector tests were the same, including the diverse corrosion-related bacteria. The biofilms on the surfaces of both types of steel were of complex composition but of the the same microbial content, i.e. they contained the same physiological groups of bacteria or bacterial species. The quantities of the diverse microorganisms in the biofilm samples developed on the carbon steel surfaces were larger than on the stainless steel. The experimental results offered new specific information, concerning the problems in the operation of this RCWS. They showed the important role microbial activity in biofouling and corrosion of the metal surfaces in contact with the cooling water.