The oil and gas industry has faced many challenges over the years - the most significant of these being corrosion control and corrosion protection. The United States contains the largest energy piping network in the world, with over 2.4 million miles of pipe traversing through mountains, forests, wetlands and urban areas. As one can imagine, it is difficult to consistently and effectively monitor such a vast network.
Oil and Gas Pipeline Corrosion Costs and Impact
According to a study conducted by the National Association of Corrosion Engineers (NACE), pipeline corrosion costs the oil and gas industry over $US 7 billion each year. Furthermore, according to one report, corrosion is cited as the second leading cause of oil and gas spills and is blamed for nearly one-quarter of all incidents.
In light of these staggering statistics, it is evident that the oil and gas industry is in need of highly effective corrosion control and protection mechanisms.
The Limitations of Current Corrosion Monitoring Techniques in the Oil and Gas Industry
Pipeline companies in the oil and gas industry are known for employing high tech leak detection systems, such as aerial scanning and other methods, to ensure that pipeline networks operate safely and effectively. However, the advanced technology used to identify leaks are typically not capable of detecting corrosion.
Traditionally, corrosion inspections are carried out using manual methods. (A pilot study is examined in Use of Non-intrusive Inspection in Onshore Gas Facilities.) While popular techniques, such as CCTV camera systems and ultrasonic testing are effective at detecting the onset of corrosion, inspection personnel are required to be present on site. (For more on these techniques, see How Closed Circuit Television (CCTV) is Changing Sewer and Pipeline Asset Management and Guided Wave Ultrasonic Testing for Non-piggable Pipelines.) Another common pipeline defect, corrosion under insulation (CUI), requires the physical removal of insulation to visually check for corrosion defects. For vast pipeline networks, these methods can be both time-consuming and costly.
To address the shortcomings of conventional monitoring techniques, the oil and gas industry is rapidly adopting innovative and smart technologies, collectively known as the internet of things (IoT). The use of this technology enables real-time monitoring of asset conditions while improving on-field communication, reducing downtime and ensuring the safety of inspection workers.
What is the Internet of Things (IoT)?
The internet of things (IoT) is a concept that involves connecting physical objects to the internet, thus making them capable of collecting and sharing data. This is done through the use of embedded electronic sensors (e.g., pressure sensors, thermocouples, and others), software and network connectivity. In simpler terms, IoT is a framework that allows data exchange between physical objects and remote computer systems over an existing network.
The rise of IoT technology is mainly attributed to the advent of inexpensive processors and wireless networks. These components make it possible to turn almost any physical object into a smart device. This adds a level of intelligence where changes in physical conditions can be communicated with little or no human interaction once the systems are installed.
The automated monitoring capabilities of IoT systems make them ideal for consistent pipeline corrosion monitoring.
How IoT is Used in the Oil and Gas Industry
Remote sensors connected to pipelines, along with appropriate software, provide actionable insights based on the collection of real-time data. For example, electronic devices integrated into piping networks can be used to detect when assets are in the process of corroding and becoming thinned (e.g., wall loss) to the point where leaks and breaks are an imminent threat.
IoT sensors work via several mechanisms, depending on the parameters they are designed to monitor. One of the most common types of sensing technologies involves measuring changes in an object’s magnetic field. In this case, IoT magnetic sensors are attached directly to a pipe, process vessel or storage tank, to identify defects (such as corrosion) that disturb the natural magnetization of the steel. This data is then collected and automatically transmitted to various channels, including systems management, incident reporting and supervisory control departments.
Other sensing technologies are used to analyze the behavior of the asset as well as its susceptibility to corrosion under different external conditions including weather changes, changing pH levels and structural loading.
Figure 1. A variety of sensors, including sensors for ultrasonic, methane gas, carbon monoxide and CO2 monitoring.
Benefits of Implementing IoT for Corrosion Monitoring in the Oil and Gas Industry
As previously mentioned, IoT permits continuous, real-time and accurate monitoring of oil and gas assets (pipelines, process vessels, tank farms, etc.) for corrosion-related defects. This allows faults to be detected in the early stages, thus minimizing repair work and associated downtime. Of particular importance is the ability to monitor corrosion in hard-to-inspect and localized areas, such as elbows and joints, where corrosion rates tend to be accelerated.
IoT sensors are also critical in protecting inspection workers and preventing the onset of catastrophic events. This type of sensing technology allows crucial inspection data to be reported wirelessly to a safe and remote location. Complete visibility of pipeline conditions can be observed from the operational floor. As a result, there is no need to physically deploy workers to hazardous environments to carry out inspections.
Systems connected via IoT can also be programmed to send alerts and instructions to other devices in the event of failure. For example, if an IoT sensor in a particular component detects potentially dangerous corrosion damage, signals are sent to other devices to take actions (e.g., sounding alarms, alerting console stations, shutting off relevant valves) that prevent leaks or the creation of unsafe conditions.
By collecting pipeline integrity data and functioning conditions over time, some corrosion failures can be anticipated and prevented using appropriate maintenance strategies. Additionally, long-term monitoring and integrity deterioration assessments can assist in the calculation of asset longevity and remaining service life. This is especially crucial when scheduling maintenance to minimize the impact on ongoing operations.
The implementation of IoT has revolutionized corrosion inspection and monitoring for the oil and gas industry. It provides a universal solution to address the safety, performance and accuracy concerns associated with conventional investigations.
Real-time plant corrosion monitoring also helps to provide data that can be used to deploy timely preventive actions using predictive analysis. In light of these benefits, many companies in the energy sector are making significant investments in IoT for corrosion monitoring.