Inhibition and Control of Microbiologically Influenced Corrosion in Oilfield Materials

摘要

Most engineering systems experience unexpected problems, premature failures and costly repairs due to damages wrecked by Microbiologically Influenced Corrosion (MIC). This research is aim at establishing the influence of certain microorganisms in increasing corrosion rate in steel coupons, characterizing and isolating the microbial strains associated with the accelerated corrosion in waterlogged clay soil area and determining the corrosion inhibitors that can effectively reduce the MIC, acting as a biocide instead of a nutrient source. Microbial count tests in both dry and waterlogged soils and Biochemical tests on isolates were conducted. Results show that effective prevention and control of MIC can be achieved through proper characterization of the microorganisms involved and understanding their specific roles in the clay soil environment. The Inhibitive Efficiency of the three inhibitors used in this study decreased in the following order: Copper (II) Chloride, Glutaraldehyde and sodium molybdate with CuCl2 giving 78.9% efficiency. The effective use of biocides helps reduce the equipment damage by lowering the rate of corrosion attack and thereby saving maintenance cost such as repair costs, lost production and lost sales.