Methane leaks in natural gas production
Methane is a major contributor to global warming. It has more than 80 times the global warming impact of CO2 and the rate at which it is being produced increases year on year. The atmospheric concentration of this gas has soared in recent years, and methane leaks and methane mismanagement are two of the leading contributors. These leaks are most commonly caused by equipment and pipeline seals failing.
However, some leaks are intentional, and oil and gas companies have been found to deliberately release methane into the atmosphere to release pressure from extraction systems - though this is largely an illegal practice. Proper monitoring and inspection can reduce the frequency and severity of these emissions, thus leading to a smaller environmental impact, as can properly adhering to governmental guidelines around methane production, use and handling.
There are a number of ways to detect methane leaks. In addition to relying on ground-based monitoring, scientists have used satellites and aeroplanes or drones to detect methane. This allows them to test the total amount of emissions and can identify sources of methane leaks that would otherwise go unnoticed. The governments of the United States of America and countries across Europe are increasingly focusing on reducing commercial sources of methane emissions as part of wider climate change initiatives.
Risks associated with methane leaks
Some methane leaks are so severe that they can cause an explosion, though this is usually a worst case scenario. A 2011 explosion in Allentown, Pennsylvania, killed five people and destroyed local homes. In San Bruno, California, a methane leak from an underground transmission line caused an explosion that killed eight people and destroyed properties and residences. Events such as these have resulted in increased public scrutiny for transmission and distribution lines and are relatively uncommon. The dangers of methane leaks are real, though, so mitigation is vital.
Not only do methane leaks in natural gas production and storage plants have the potential to cause explosive events, they can also cause fires and can be damaging to human and environmental health. While breathing methane is not inherently dangerous as it is non-toxic, breathing high concentrations can lead to hypoxia, shortness of breath, headaches and other health issues, especially if the gas contains concentrations of other more toxic elements and compounds. Environmentally speaking, methane can dissolve into waterways causing deoxygenation and damaging aquatic ecosystems.
The biggest methane leaks are the most dangerous. In addition to methane, the gas can contain toxic gases, carcinogens, and other harmful substances that affect the lives of the people in the vicinity. The leaks are most often found in underdeveloped areas where the health of the population is poor, though there is the potential for this kind of leak anywhere that methane and natural gas is handled in high volumes.
Detecting methane leaks
Fortunately, technology has made it easier to spot methane leaks. As methane is a colourless, odourless gas, leaks are difficult to detect without the help of infrared cameras and other such equipment. Today, cameras and other monitoring equipment in gas production facilities can detect even the smallest of all leaks under ideal conditions, including low wind, clear skies, and within a certain distance of the equipment.
These sensors detect methane leaks and many provide additional data on concentration, volume, flow rate and more. This makes methane emissions from gas plants much less dangerous than they were in the past as it is easier to spot them quickly before they can become a serious problem.
A recent study from the USA found that methane leaks are more likely to occur in cities than in smaller towns. In addition, it has been found that major leaks are more likely to be caught and fixed quickly, while minor ones go unnoticed and can remain undetected for months or years. Because leaked natural gas is a potent greenhouse gas, the effects of methane leaks are significant. Consequently, it is important to take measures to reduce these emissions as far as possible by installing adequate monitoring systems, and having a plan in place should a leak occur.
Where are leaks likely to occur
Methane leaks often occur near natural gas gathering and transportation points. It is also quite common for leaks to be found at joins in storage and transportation systems, including supply lines. Additionally, methane can leak directly from gas sources such as landfills and other waste disposal and treatment plants. They can be caused by human error, though it is more common to see leaks take place because equipment has developed a fault, pipes have corroded, or some other technical issue.