Assessment of MIC in Carbon Steel Water Injection Pipelines

Abstract

The present study compares corrosion mass loss and pit depth measurements on carbon steel corrosion coupons exposed under similar operating parameters, but with different biological consortia. One set of data were obtained from standard flush disc corrosion coupons used to monitor corrosion rates in a water injection pipeline on the North Sea continental shelf. The coupons were exposed on average for 6 months over 6 years operational time. These data are compared with published corrosion data of coupons exposed in abiotic district hot water systems from several power plants situated in Europe. The exposure time for these coupons was 9 months. Both systems were anoxic and in the same temperature range and are comparable. Observations regarding relationship between MIC and bacterial consortia, bacterial numbers and type, water quality and corrosion products are also made. The corrosion rate of the water injection pipeline is approximately 10 times higher compared with the corrosion rate in the abiotic district hot water system. It is concluded that the increased corrosion on the carbon steel coupons in the early stage is caused by MIC. This is also supported by the chemical and biological information available for the pipelines. The results reported here constitute the first step of an overall study to improve the level of understanding of the bacterial contribution to the total corrosion rates of carbon steel in water injection flowlines. Such understanding is expected to improve management and operational decision-making for practical control of corrosion in the field, by providing predictions of expected life time as a function of control of biotic consortia (e.g. through pigging, and biocide treatments). Further, it will facilitate decisions concerning choice of pipeline construction materials for future design.

Proteins identified through predictive metagenomics as potential biomarkers for the detection of microbiologically influenced corrosion

“…However, the limited amount of corrosion observed (up to 0.06 mm/year) suggests a passivation phenomenon rather than active biocorrosion. A more environmental-oriented study from Comanescu et al found that water injection pipelines for secondary oil recovery with average temperatures 50–60°C presented deeper pits and higher bacterial counts than those with average temperatures between 60 and 120°C (Comanescu et al, 2012 ). Although interesting, such study is probably less relevant for production pipelines, since a low amount of oxygen is present in water injection pipelines, along with different pools of electron donors and acceptors, correlated with the origin of the waters (groundwater, seawater, or river/lakes).…”

Corrosion of carbon steel in presence of mixed deposits under stagnant seawater conditions

“…The severe channelling corrosion sometimes observed in offshore water injection pipelines is assumed to be associated with microbiologically influenced corrosion and much attention has been given to this possibility in the practices adopted by industry (Comanescu et al, 2012;Comanescu et al, 2016;Heidersbach and van Roodselaar, 2012). The potential influence of under-deposit corrosion has been given much less attention even though there is circumstantial evidence for it from field observations (Heidersbach and van Roodselaar, 2012).…”

Control of Microbiologically Influenced Corrosion using Ultraviolet Radiation

“…Microbiologically influenced corrosion (MIC) such as sulfate reducing bacteria (SRB) in biofilm consortia has signalled the role of this particular bacterium in the process of corrosion in pipelines and seawater injection systems (AlAbbas 2013; Almahamedh et al 2011;Comanescu et al 2012;Maxwell & Campbell 2006). It is well-known that MIC can oxidize a wide variety of chemicals and use them as nutrient sources and enhance their proliferation.…”