Exploring NRB Biofilm Adhesion and Biocorrosion in Oil/Water Recovery Operations Within Pipelines

Area of Science:

• Materials Science
• Microbiology
• Corrosion Engineering

Background:

• Microbially influenced corrosion (MIC) poses a significant threat to the longevity of carbon steel infrastructure.
• Nitrate-reducing bacteria (NRB) are key contributors to MIC, especially in oil and gas operations.
• Understanding biofilm formation is crucial for mitigating corrosion in pipelines.

Purpose of the Study:

• To investigate the impact of NRB biofilms on carbon steel corrosion in Algerian oil/water recovery pipelines.
• To compare the corrosive effects of injection water and crude oil environments on carbon steel.
• To elucidate the mechanisms behind NRB-mediated biocorrosion.

Main Methods:

• Microbial analysis (sessile and planktonic cell counts).
• Gravimetric methods (weight loss measurements for corrosion rate determination).
• Surface characterization (contact angle measurements, Scanning Electron Microscopy).

Main Results:

• Carbon steel in injection water showed a corrosion rate of 0.0125 mm/year, versus 0.0042 mm/year in crude oil.
• Injection water contained significantly higher microbial populations (sessile and planktonic) than crude oil.
• SEM revealed extensive biofilm and corrosion pits on steel exposed to injection water, unlike crude oil samples.

Conclusions:

• Injection water is a primary driver of NRB biofilm formation and subsequent microbially influenced corrosion in these pipelines.
• Enhanced hydrophilicity of carbon steel in injection water facilitates greater biofilm adhesion.
• These findings highlight the need for strategies to manage microbial contamination in injection water to protect pipeline integrity.