ALIA Webinar: The role of re-refined base oils in a circular economy

The significance of re-refining waste oil is on the rise as the lubricant sector ardently adopts a sustainability agenda amid global environmental challenges. While this may seem like a relatively recent initiative, re-refining is not a new concept. Several global refiners have been operating for decades—optimising their processes, technology and product quality over time.

Re-refined base oils (RRBO) are an integral part of our collective effort to transition towards a circular economy and reduce product carbon footprints (PCF). However, there are still a lot of misconceptions out there when it comes to RRBO.

One of the main challenges is a legacy perception that RRBO products do not have the requisite quality or performance, says Mark Southby, industry liaison manager and sustainability lead at Shell Lubricants Technology. Over the last 15 years, the quality of RRBO has increased hugely, he says. While not all RRBOs are the same, we now have RRBOs which meet the specifications of API Groups I, II and III in North America and Europe and Groups I and II in Asia.

There is a need for updated information for industry professionals and stakeholders to try to tackle some of these misconceptions. On January 18, 2024, the Asian Lubricants Industry Association (ALIA) held a webinar on Product Circularity of Re-refined Base Oils where industry experts outlined the fundamentals of RRBO. Dr. Detlev Bruhnke, a board member at Avista Oil AG, and Inga Herrmann, sustainability lead at Ergon International, joined Southby to discuss RRBO manufacturing, quality and performance, as well as key topics such as legislation, health, safety and environment (HSE), and product carbon footprint (PCFs). The session was facilitated by Charlotte Kehoe, technology director at bp Castrol and the current chair of ALIA and ALIA’s Sustainability Subcommittee.

Adoption of RRBO offers significant advantages in waste reduction and the conservation of resources, lowering greenhouse gas emissions and meeting ever-increasing regulatory requirements. It reduces exposure to fluctuations in crude oil supply, as well as enhancing a company’s reputation and brand.

Raw materials and end-of-life phases are the largest contributors to value chain emissions. While a shift to RRBOs demonstrates a commitment to a cleaner environment, it also results in a lower PCF than virgin base oils because it carries no upstream burden. RRBO will have 20-40% lower carbon dioxide emissions compared to a virgin base oil in the same group, according to Shell.

“I’ve heard many people talking about RRBO as if they’re completely different to virgin base oils,” says Southby. While a big range of quality and performance exists for RRBO, this is also true for virgin base oils. RRBO should be treated the same as virgin base oils and fall into the same API base oil classification, as defined by their physical and chemical properties, he says.

ATIEL is the technical association of the European lubricants industry. Southby is chair of the ATIEL RRBS (Re-Refined Base Stock) Sub Group, part of ATIEL’s Sustainability Committee. ATIEL’s position is that there shouldn’t be mandates on the use of RRBO. Formulators need the freedom to create finished lubricants to meet increasingly demanding technical requirements. Some finished products can accommodate large percentages of RRBO. In others, it might be detrimental to performance. We wouldn’t want to reduce sustainability-related benefits—such as avoided emissions from fuel economy or extended drain intervals—by mandating the use of RRBO, says Southby.

India and Turkey have both introduced mandates to drive the adoption of RRBO. Turkey established regulations related to the management of used oils in December 2020, with a progressively increasing target on RRBO content in finished lubricants, starting at 8% in 2024.

An extended producer responsibility (EPR) scheme extends a producer’s responsibility to the post-consumer stage of a product’s lifecycle. India’s EPR guidelines require 5% RRBO content in finished lubricants from April 1, 2024—increasing annually to 50% by 2029.

Europe has no plans to mandate the use of RRBO. Southby, who was actively involved in updating the Waste Framework Directive with the European Commission, notes there is no mention of mandating RRBO. The directive does suggest waste oil is collected responsibly and this will facilitate waste oil moving more towards re-refining, instead of being burned as fuel.

There have been recent reports of some original equipment manufacturers (OEMs) insisting on minimum RRBO content in lubricant products. However, the panel members were unaware of any impending legislation mandating RRBO. Vietnam recently introduced an EPR programme, but there are still questions about how it will be executed, says Kehoe. Australia’s product stewardship scheme is focused more on rebates for those that convert to reusable products, not mandates, she says.

The number one challenge in achieving commercial scale in RRBO use in lubricant formulations is the availability of good quality feedstocks, says Bruhnke. In some instances, it is not technically feasible to re-refine the used oils as they are heavily contaminated, and some waste oils that were used in certain applications are not suitable to be re-refined, he says.

While the consensus is that we shouldn’t mandate the use of RRBO in formulations, the same cannot be said when it comes to feedstock collection. There is a need for practical regulations to incentivise the market, including used oil producers and collectors, to embrace a degree of circularity, says Herrmann. Small steps are being taken in countries like Peru and Chile to encourage the collection of waste oil, she says.

RRBO can drive circularity, without compromising quality and performance. However, even though the quality has changed markedly over the last few years, not all re-refined base oils are safe, says Southby. The re-refining process must be capable of removing harmful contaminants. The Shell representative highlighted the importance of rigorous testing protocols for both virgin base oils and RRBOs to ensure safety and performance.

Feedstock for RRBO differs from virgin base oils and the related health hazards also differ. We need to ensure lubricating base oils are not harmful to humans and the tests used are appropriate.. For example, the carcinogenicity of virgin base oils is controlled through the IP346 test. Shell does not consider this test to be applicable for RRBO. A modified Ames test ASTM E1687-19 is a more appropriate way to screen for carcinogenicity properties, he says.

The full ALIA webinar, including a breakdown of different re-refining processes and emerging technologies, is available in the members-only section of the ALIA website.