Accelerated Low Water Corrosion
ACID researchers at Swinburne University of Technology are using cutting edge science to learn about the community of microbes responsible for accelerated low water corrosion (ALWC), with the aim of developing diagnostic techniques and mitigation/prevention strategies.
Extremely rapid corrosion (up to several mm/year) of port/harbour infrastructure can occur at the low water level due to the interaction of microbes with the structure of interest (e.g. sheet piling walls or tubular support piles). This can lead to rapid degradation of structural integrity and the requirement for expensive repairs as well as loss of earnings and/or asset availability.
What we are doing
Together with a multidisciplinary team of microbiologists, metallurgists and corrosion scientists we are investigating what causes accelerated low water corrosion. This includes using a combination of traditional and the latest microbiological methods to understand the community of microbes responsible. While sulfate reducing bacteria (SRB) are often exclusively implicated as being responsible for ALWC, in reality there is a complex community of different types of microbes. This group of microbes works together and it is the interactions between them as well as the metal surfaces that leads to the acceleration of corrosion. As such, it is critical to determine the various microbes present and to better understand the roles that they play.
At present there are no standard methods for diagnosing/verifying whether a structure is suffering from accelerated low water corrosion. Verification can provide an asset owner with critical information about potential changes required to long term planning of structures at the site in terms of remaining structural life, due to changes in corrosion rates of the structure. We are developing methods/procedures for the verification of ALWC that are designed for general use and minimise the requirements for complicated laboratory equipment and/or high-level scientific expertise.
What are the outcomes/impacts
- Understanding of the mechanisms responsible for ALWC
- Standard methods for the diagnosis/verification of ALWC
Orange bloom (often associated with accelerated low water corrosion) on marine sheet piling.