Closed-loop sidestream systems that simulate cooling water conditions are being used to investigate corrosion control using regenerative biofilms (CCURB) at the UC Irvine Central Generating Facility. The closed-loop operation avoids possible ground loop problems associated with electrochemical measurements and permits the investigation of bacterial treatments prior to approval for use in the target service water systems. These treatments are being developed as alternatives to the use of biocides and inhibitors for controlling corrosion. Electrochemical impedance spectroscopy and mass loss measurements were performed with coupons and pipe samples of 1018 mild steel under different flow conditions in service water that was inoculated with engineered bacteria. A comparison of these results with those for samples simultaneously exposed to unaltered service water indicates that the engineered bacteria significantly reduce the corrosion rate of mild steel under service water conditions. It was also noted that corrosion control by the engineered bacteria was less effective for samples that were installed at the time of inoculation as opposed to those pre-exposed to unaltered service water. Furthermore, the addition of supplemental nutrients did not enhance the corrosion control by the engineered bacteria.
All Science Journal Classification (ASJC) codes
- General Chemistry
- General Chemical Engineering
- General Materials Science