Five Questions for a leading authority on pipeline corrosionPublished: May 3rd 2017
Microbiologically-Influenced Corrosion (MIC), or microbial corrosion, is the deterioration of metals by certain microorganisms found in water and soils. MIC is a problem for many industries including onshore and offshore oil and gas operations. Responding to the constant threat of pipeline leaks from the direct and indirect effects of MIC corrosion costs the oil and gas industry billions of dollars annually in corrosion monitoring, control and repairs.
For a plain-speaking perspective on this complex and poorly understood phenomenon, Genome Atlantic contacted Calgarian, Dr. Tom Jack, a leading authority on the subject.
Few microbiologists command the oil and gas industry’s attention like Dr. Jack. His work is widely acknowledged for significantly improving the scientific understanding of bacterial oilfield and pipeline corrosion. Although he has been retired from NOVA Research and Technology Centre since 2005, he retains a formidable presence in his field as a consultant and as an adjunct professor and research associate, Petroleum Microbiology Research Group, University of Calgary. He was NOVA Research and Technology Centre’s first scientist and stayed with the organization for 25 years.
Dr. Jack has led programs on enhanced oil recovery and environmental stewardship for companies in the NOVA group, including Husky Oil, NOVA Gas Transmission, Foothills Pipelines, TransCanada Pipelines and NOVA Chemicals. He is a Fellow of the Chemical Institute of Canada, a recipient of the Alberta Premier’s Award of Excellence and the NOVA Chemicals President’s Responsible Care Award. His scientific credentials include more than 200 proprietary reports, seven patents, and more than 100 articles in scientific and technical journals.
Currently he is lending his expertise to the $7.9 million Managing Microbial Corrosion in Canadian Offshore and Onshore Oil Production project, funded in part by Genome Canada. Co-managed by Genome Atlantic and Genome Alberta, this is a collaborative multi-disciplinary venture led by the University of Calgary, the University of Alberta and Memorial University of Newfoundland. Project partners for the Atlantic portion of the project also include Dalhousie University, Husky Energy, Suncor Energy, LumniUltra, Petroleum Research Newfoundland and Labrador (PRNL), Research and Development Corporation of Newfoundland and Labrador (RDC), and Mitacs.
When Genome Atlantic connected with Dr. Jack, he had just returned from NACE2017 in New Orleans, the world’s largest corrosion conference, convened by the National Association of Corrosion Engineers International or NACE.
Genome Atlantic: Microbiologically influenced corrosion accounts for about 20 percent of corrosion failures in oil and gas pipelines. How significant an issue is it for the oil and gas industry, and does the industry view other factors as more critical?
Dr.Jack: Yes there are other causative factors (such as oxygen or acid gas), but the corrosion mechanisms involved are more predictable and better understood. In contrast, microbiologically influenced corrosion (MIC) can cause rapid corrosion failures to occur under chemical conditions that seem otherwise relatively benign, and in places not predicted by chemical and physical factors. The oil and gas industry routinely injects biocides to control microbial activity in many of its operations, based on past experience and a record of improved performance where such chemicals are used. A better understanding of where and when MIC failures might occur and the processes involved offers the prospect of more efficient and effective prevention of MIC related failures.
Genome Atlantic: Although MIC was first reported in the 19th century, the explanations of how and why the phenomenon occurs under most operating conditions in the oil and gas industry are still unclear. Why has science been so slow to provide the answers?
Dr. Jack: As implied in the phrase ‘microbiologically influenced corrosion’, microbial communities present in most oil and gas operations can cause corrosion failures to occur by many mechanisms. It is not a single phenomenon. Added to this complexity has been a lack of comprehensive tools for examining the microbial communities involved in MIC. The traditional tools used by microbiologists were limited to assays (culture based), based on the ability to grow microorganisms in selective media. Because only a very small fraction of the organisms present could be grown in known media the picture of the microbial community involved in a corrosion scenario obtained was extremely limited.
Early application of genomics has overcome this limitation by allowing complete communities to be characterized. Modern bioinformatics techniques used to understand the large amount of information generated now allow organisms to be identified more extensively and more precisely, and give insights into how these communities may be organized and the metabolic processes that may be occurring within the community.
Genome Atlantic: In your experience, does the industry factor MIC into its selection of materials for new construction as much as it could or should? For instance, could wider use of titanium alloys, more resistant to corrosion than carbon steel, significantly reduce the role of microbiologically influenced corrosion in sub-sea and offshore production?
Dr. Jack: In some applications steel is being replaced by non-metallic materials which are not susceptible to corrosion. Examples include use of high-density polyethylene pipe in relatively low-pressure natural gas distribution systems, or the use of line pipe made of fiber reinforced plastic in oilfield gathering systems. Plastic liners are also used inside steel pipes to arrest corrosion and control leaks. In larger, higher-pressure systems, carbon steel remains the material of choice. Exotic metals such as titanium are too costly for general use in the extensive systems required for oil and gas production and transportation, but stainless steels are used where it makes sense to do so.
Genome Atlantic: Is there a relationship between MIC in the sub-sea and offshore environment and souring of offshore oil and gas? Aren’t microbes at work in both activities?
Dr. Jack: Absolutely. Souring offshore occurs in deep hot oil reservoirs lying below the sea floor where seawater injection is used to maintain reservoir pressure and push oil to the surface. Prolonged injection of seawater cools the region around the injection well and introduces water, sulfate and microorganisms into the oil bearing formation. The result is an upsurge in anaerobic sulfate reducing microbes that convert seawater sulfate to sulfide as an essential part of their metabolism. The hydrogen sulfide ultimately produced is toxic and can lead to corrosion and cracking problems in production facilities sub-sea and topside. Introduction of sulfide into topside operations may also trigger other sulfur cycle processes including ones catalyzed by microorganisms. These processes can result in unexpected threats to system integrity through the generation of thiosulfate, elemental sulfur and other chemical species. Investigation of sulfur cycling and the threat it poses to topside facilities offshore is a key aspect of the present project.
Genome Atlantic. What hurdles do investigators face when trying to establish MIC as the probable cause of a component failure?
Dr. Jack: The rapidly developing field of genomics is allowing researchers to get a complete picture of microbial communities in field samples from corroding systems for the first time. The challenge will be to link specific organisms, communities, activities or metabolic products to specific corrosion scenarios. Obtaining the right samples and setting up realistic test systems in the laboratory is a key issue and will entail close collaboration with project partners in the oil and gas industry. These partners include operators of the pipeline and offshore facilities that are the principal areas of focus for the (Managing Microbial Corrosion in Canadian Offshore and Onshore Oil Production) project as well as biocide suppliers and service companies already engaged in applying genomic analysis to field problems.
Genome Atlantic. How optimistic are you that the current four-year Managing Microbial Corrosion in Canadian Offshore and Onshore Oil Production project will provide answers to better predict, how, where and why MIC occurs and how to mitigate it?
Dr. Jack: I am quite optimistic. Progress to date has shown this to be a promising field. New methods of sampling, sample preservation, analysis and interpretation are already emerging; however, they have only been applied in a haphazard way across the industry to date. The multi-disciplinary nature of the research team in the current four-year Managing Microbial Corrosion in Canadian Offshore and Onshore Oil Production project will allow a much better perspective on what is occurring in operating systems and its implications for corrosion control and risk management. The project has specific deliverables in terms of knowledge, models to predict corrosion and manage risk and methods, tools and devices for field use. Substantial effort is embedded in the project work plan to transfer these deliverables to industry through an extensive network of industry partners and through organizations such as the National Association of Corrosion Engineers International (NACE), industry associations and other agencies responsible for developing and updating standards that are used by the oil and gas sector internationally to address the threat of corrosion.
Learn more about the Managing Microbial Corrosion in Canadian Offshore and Onshore Oil Production project