One question that various friends ask when they learn we work with many oil industry companies is, “Are we running out of oil?” The answer is no. There’s still plenty of oil and gas, but new sources are more difficult to extract, and the crude is often lower quality. Low-quality in this context generally means sour, based on sulfur content. The biggest problem with sour oil is its corrosiveness—it destroys equipment, costing industry trillions of dollars every year, and it has caused countless loss-of-containment incidents globally.
Beginning back in 1975, the National Association of Corrosion Engineers (NACE) published a group of standards for dealing with corrosive products, including critical effects of material selection. These standards have been updated and expanded over the years and are now widely used throughout the chemical and oil & gas industries. They offer guidance on material selection for piping, valves, and vessels. We wrote an article reviewing these standards in the February issue of Oil & Gas Engineering, showing how corrosion can have significant negative consequences.
The presence of sulfides in oil and gas creates additional challenges down the value chain until the sweetening process, which is used to remove sulfides from sour gas or oil. Hydrogen sulfide (H2S) in process media presents significant risks to hydrocarbon facilities in terms of cost, equipment damage, and harm to personnel.
The importance of these standards and the whole issue of corrosion is only getting worse:
The oil and gas industry has shifted more of its production to fields where sulfur and other corrosive agents are more abundant. A 4 parts per million (PPM) concentration of hydrogen sulfide in air under standard temperature and pressure is often referred to as sour, and crude oil with more than 0.5% sulfur is called sour crude. According to the International Energy Agency (IEA), about 43% of the world’s natural gas reserves are sour. The gas reserves in the Middle East, for example, are estimated to be about 60% sour.
Anyone working in an upstream oil & gas facility, a refinery, or many types of chemical plants, needs to understand these standards and how to apply them. The article is an excellent basic resource. There is also a webinar titled Wouldn’t it be NACE?, where we share what end users and vendors need to know from these standards, how they apply to the hydrocarbon value chain today, and the importance of reducing corrosion in severe applications in such facilities across the world.
Emerson’s portfolio of valves, actuators, and regulators offers an enormous range of configurations and materials designed to withstand corrosive crudes and other chemicals. What’s happening in your facility? Are you using effective strategies for managing corrosion? Visit the Valves, Actuators, and Regulators pages at Emerson.com to learn more about how you can improve your existing efforts.
Also, visit the Corrosion and Erosion Monitoring pages for products and techniques for measuring the effects of corrosion in real time. You can also connect and interact with other engineers in the Oil & Gas and Chemical Groups at the Emerson Exchange 365 community.
