It’s no secret that the lubricants industry is laser-focused on sustainability right now. After all, many countries around the globe are passing stringent legislation that is requiring lubricant industry players to reevaluate how and what they blend. What’s more, consumer demands are also placing more pressure on lubricant marketers, forcing them to come up with creative ways to please their customers while meeting specifications and turning a profit.
Enter rerefined base oils.
In an effort to create more circular processes and to cut back on the quantities of virgin material that they use to blend lubricants, many lubricant formulators are now placing a stronger emphasis on rerefined base oils. And while using rerefined oils may seem to some like a new practice, industry veterans know that the recycled oils have actually been around for quite some time.
“Rerefining has been a part of the base oil industry essentially since its inception,” Ernie Henderson, president of K&E Petroleum Consulting, said in a panel discussion at the ICIS Pan American Base Oils and Lubricants conference in December. “When the Groups were created by API and ATIEL back in the early 1990s, we specifically made the definitions such that rerefined base oils could be incorporated in our definitions along with virgin base oils. So we set the stage from the very beginning to allow rerefined base oils to be part of that—of the industry and the base oil network.”
So how have rerefined base oils benefitted the industry up until now, and how might they help to secure the future of the industry in a rapidly changing world?
Rerefined Base Oils Meet Sustainability
If rerefining base oils seems like a solid step toward sustainability, that’s because it is. Most obviously, blending lubricants with rerefined base oils lessens the volume of virgin base oils that must be used, preserving finite natural resources such as crude oil.
Furthermore, rerefining used engine oil into base oil prevents used oil from being burned off or dumped into the environment. All too often, used engine oil is not disposed of properly and ends up polluting water, air or soil. Collecting and rerefining used oil prevents such pollution.
Additionally, according to the United States Environmental Protection Agency, less energy is required to produce a gallon of rerefined base oil than is required to produce a base stock from crude or other feedstocks.
Rerefining Evolution
Just like the processes used to refine virgin base oils, the processes used to make rerefined base oils have undergone necessary changes over the years to improve their safety, their efficiency and the quality of the end product.
“My company started developing technologies for rerefined base oils in 1995. At that time, the existing technology was rather primitive and also really polluting,” Luke Staengl, CEO of Pragmatic Environmental Solutions, said in the panel discussion. “There are a number of players that have tried all kinds of different things, but we decided to go to a relatively straightforward, traditional chemical engineering approach, which was to vacuum distill the incoming used lube oil. What we found was that the better the vacuum, the better the product.”
Staengl explained that in order to make most rerefining plants work, especially the ones that produce base oils on a smaller scale, “we had to develop technologies that were quite low impact, low danger, lower cost, etc. … So, we focused a lot of attention on using solvent extraction as the step right after the distillation process and were able to produce good Group I oils from that. Depending on the input, we were able to develop Group II oils and, in some rare cases, even Group III.”
Quality of Rerefined Base Oils
Some consumers may have concerns that finished lubricants made from rerefined base oils might not possess the same level of quality as those made from virgin base oils. Fortunately, a few of the panelists were happy to set the record straight.
“Rerefined base oil technologies have come a long way, and the quality of the oil is now exceptionally good—sometimes even better than virgin base oils,” Joshua Park, president and CEO of Chemical Engineering Partners, said. “With the use of hydrogen technologies, you can produce an extremely high-quality rerefined base oil.”
Varun Chopra, vice president of sales for Safety-Kleen agreed: “I would probably go one step further and say that, at least at Safety-Kleen and many other rerefiners in North America, we make Group II+ base oils.” He added that the rerefined oils made by Safety-Kleen are able to meet today’s engine oil specifications and that they even surpass expectations.
What factors determine the possible quality level of a rerefined base oil?
According to Staengl, as a general rule, the quality of the input material determines the quality of the rerefined base oil.
Erica Snedegar, vice president of business development for Vertex, agreed: “When we first started our rerefinery in 2008, the VI (viscosity index) very consistently was somewhere around a 113 or a 114. As the engine oils out there improved, we consistently saw really no technology improvements. We saw VI creep up to very consistently 118 or 119. That is actually with no capital improvement within the plant—that’s just the quality of the used oils we’re seeing. So it’s getting there—the quality of the rerefined Group II.”
On the commercial side, Snedegar explained that there was some misconception in the industry regarding the quality of rerefined base oils. “Back when I got into the industry and was selling base oils, there was a stigma that rerefined base oils were subpar and weren’t as good as virgin ones,” she said. “I think that that messaging was probably put out there on purpose, and there was a longer scale of difficulty trying to move the product. Today, it’s just as easy to sell rerefined as it is virgin.”
Sydney Moore is managing editor of Lubes’n’Greases magazine. Contact her at Sydney@LubesnGreases.com