Corrosion control and integrity management in pipelines

Author: Ing. Antonio Zavarce, August 24, 2023.

Introduction

Pipelines are the arteries of the modern industrial world, transporting fluids such as oil, gas, and water over vast distances. However, like any infrastructure, they are susceptible to degradation over time, hence the importance of corrosion control. Ensuring pipeline integrity isn’t just about preventing leaks; but to safeguard the environment, protect assets and ensure the safety of communities. This article delves into the importance of pipeline corrosion control and integrity management best practices.

Understanding corrosion in pipelines

Corrosion is the natural process by which metal deteriorates due to chemical or electrochemical reactions with its environment. In pipelines, this can be caused by several factors:

• External Corrosion: Caused by environmental factors such as soil composition, moisture content, and microbial activity.
• Internal Corrosion: Resulting from the transported materials, especially if they contain water, acids or other corrosive agents.
• Galvanic corrosion: Occurs when two metals of different potentials are in contact, reacting electrochemically.

The importance of corrosion control

The implications of uncontrolled corrosion are multiple:

1. Safety Concerns: Corroded pipes can rupture, leading to catastrophic events, especially in the case of flammable or toxic materials.
2. Financial Implications: Leaks or failures can result in significant financial losses due to downtime, cleanup, and potential legal liabilities.
3. Environmental Impact: Spills can have devastating effects on local ecosystems and water sources.

Pipeline Integrity Management: A Holistic Approach

Integrity management goes beyond simply monitoring corrosion. It is a comprehensive approach that ensures the safe, reliable and efficient operation of the pipeline. Key components include:

1. Risk assessment: Identify potential threats, from corrosion to natural disasters, and assess their probability and potential impact.
2. Inspection and Monitoring: Regularly review the condition of the pipeline using tools such as Smart Pigging, ultrasonic testing, and real-time monitoring systems.
3. Maintenance and Repair: Proactively address identified issues before they escalate.
4. Data Management: Collect, analyze and store data to inform decision making and ensure compliance with regulations.

Corrosion Control Best Practices

1. Cathodic Protection (PC): Electrochemical method using; which reduces the anodic (corrosive) reaction on the metal surface. There are two types of PC: sacrificial anode and impressed current.
2. Protective Coatings: Apply a barrier between the metal and the corrosive environment, such as fused epoxy or polyethylene wraps.
3. Corrosion Inhibitors: Chemicals that, when added to the transported product, reduce its corrosivity.
4. Piping Design: Considering factors such as material selection, wall thickness, and construction practices can inherently reduce corrosion risks.
5. Regular cleaning: Using pipe pigs to clean the internal surface can prevent the buildup of corrosive agents.

The role of technology in Integrity Management

Modern technology plays a fundamental role in improving the integrity of pipelines:

1. Smart Pigs: These devices move inside the pipe, using sensors to detect anomalies such as corrosion, cracks or dents.
2. Remote monitoring: Sensors along the pipeline transmit data in real time to control centers, allowing an immediate response to possible problems.
3. Data analysis: Advanced algorithms can predict potential failure points, optimizing maintenance schedules.

The human factor

Although technology is crucial, the human element cannot be underestimated. Well-trained personnel, from field technicians to data analysts, are the backbone of any integrity management program. Ongoing training and adherence to safety protocols ensure that both the pipeline and the people who supervise it remain safe.

Applied cases, successes and technologies in corrosion control and pipeline integrity management

1. Case Applied: The Trans-Alaska Pipeline

• Problem: This pipeline, which stretches for more than 1,300 km, faces extreme challenges, including sub-zero temperatures and difficult terrain.
• Solution: A combination of cathodic protection, special coatings, and regular monitoring was implemented to prevent corrosion.
• Result: Despite the extreme conditions, the pipeline has operated with a minimal number of corrosion-related incidents since its construction in the 1970s.

2. Technology: Smart PIGs (Pipeline Inspection Gauges)

• Description: These devices travel inside the pipeline and use advanced technologies, such as ultrasound and MRI, to detect and locate defects.
• Success: They have enabled companies to identify and address potential problems before they become catastrophic failures, saving millions in costs and avoiding environmental disasters.

3. Case Applied: Keystone Pipeline

• Problem: Despite being a relatively new infrastructure, corrosion problems were identified in certain sections.
• Solution: Smart PIG technology was used to identify problem areas, followed by targeted repairs and upgrades to cathodic protection systems.
• Result: A potential large-scale failure was avoided and the life of the pipeline was improved.

4. Technology: Remote monitoring and IoT (Internet of Things)

• Description: Sensors installed along the pipelines transmit data in real time to control centers using IoT technologies.
• Success: This technology has enabled faster response to problems, from changes in pressure to small leaks, reducing downtime and preventing major incidents.

5. Case study: Nord Stream gas pipeline in the Baltic Sea

• Problem: The saline marine environment posed a high risk of corrosion for this subsea pipeline.
• Solution: High-density polyethylene coatings were applied and an impressive cathodic protection system was implemented.
• Result: The pipeline has operated at optimum performance, with minimal corrosion problems despite the challenging environment.

6. Technology: Drones and Robots for Inspection

• Description: These self-contained devices can inspect pipelines in inaccessible or dangerous areas, providing high-resolution images of potentially corroded areas.
• Success: They have improved the efficiency and safety of inspections, allowing companies to identify and address problems at an early stage.

Corrosion control and Integrity Management in the energy transition towards Hydrogen

The energy transition to cleaner sources, such as hydrogen , not only represents a challenge, but also an opportunity to apply and adapt integrity management and corrosion control techniques developed in the oil and gas sector. Here are some technical tips that may be helpful:

• Assessment of existing infrastructure: Current inspection and monitoring techniques can be used to assess the integrity of existing pipelines and storage systems. This will make it possible to determine which infrastructures can be reused, which need modifications, and which need to be replaced.
• Coating Adaptation: Anticorrosion coatings developed for oil and gas can be adapted or modified to be resistant to hydrogen. Research in this field can draw on decades of experience in corrosion protection.
• Continuous monitoring: Real-time monitoring technologies, such as corrosion sensors and internal inspection tools, can be tailored to detect specific hydrogen-related problems, such as hydrogen embrittlement or accelerated corrosion.
• Design of new facilities: The experience in the design of pipelines and storage systems that minimize corrosion and maximize integrity can be applied in the construction of new infrastructure for hydrogen. This includes the choice of materials, the design of flow systems and the implementation of cathodic protection systems.
• Education and Training: Professionals who already have experience with corrosion control and integrity management in the oil and gas sector can be specifically trained on the challenges associated with hydrogen. This combination of experience and specialized training will be invaluable.
• Regulatory development: Regulations and standards developed for oil and gas can serve as the basis for developing hydrogen-specific regulations. These new regulations can benefit from decades of experience in ensuring the security and integrity of infrastructures.
• Research and development: Institutions and companies that have invested in corrosion control and integrity management research for oil and gas can refocus their efforts on the specific challenges of hydrogen, drawing on their vast knowledge and experience.

Conclusion

Developed and refined in the oil and gas industry, corrosion control and integrity management offer tools, techniques and insights that will be critical in the energy transition to hydrogen. The adaptation and application of these techniques will not only guarantee the safety and efficiency of the new infrastructures, but will also accelerate the transition towards a cleaner and more sustainable energy matrix.

References

Own source