SINGAPORE – ExxonMobil has reached mechanical completion of its Singapore Resid Upgrade Project, and is expected to bring new API Group II capacity online before the end of the year, sources commented on the sidelines of the 17th ICIS Base Oils and Lubricants conference taking place here.
There has been much speculation about the timing of the project’s start-up, with some expecting it to occur in July and others in December. While ExxonMobil has finished the construction part of the project, the plant commissioning is a complicated process that requires completion of many different steps and phases. The company has not communicated a specific start-up date, but it reiterated that the new capacity would be coming on stream some time in the second half of 2025. The upgrade was originally scheduled for start-up in 2023 but was later delayed due to the COVID-19 pandemic, which caused workforce disruptions.
The project adds around 20,000 barrels per day capacity of light, heavy and extra-heavy Group II base stocks, of which 6,000 bbl/d will be extra-heavy base stocks, including a new product that has kinematic viscosity of 32.5-35.5 square millimeters per second at 100 degrees C. This means it is as heavy as Group I bright stocks. ExxonMobil’s bright stock 150 has kinematic viscosity of 30.6-32.7 mm2/sec at 100 C.
Global bright stock supply declined by more than 20% between 2010 and 2024 as a result of Group I plant rationalizations, including those of an ENI unit in Italy, the Sapref facility in South Africa and two Eneos plants in Japan over the past three years.
A typical Group I bright stock contains a high number of waxy molecules that crystallize below the pour point temperature. The near absence of crystallizable molecules below pour point in the extra-heavy Group II oil coming from Singapore enables it to perform better in challenging operating conditions at low temperatures. Group I bright stock also has mono-ring and multi-ring aromatics that are not present in Group II oils. Group I base oils generally have one advantage over Group II base stocks: A higher proportion of unsaturated molecules means greater solubility of chemical additives. Finished lubricants containing Group II base stocks often require different additive formulation.
ExxonMobil claims its Singapore facility will be the first Group II plant to produce a cut meeting typical viscosity characteristics of a Group I bright stock.
While demand for extra-heavy neutral base stocks in engine oils will likely continue to fall due to lower-viscosity trends, this is expected to be largely offset by the need for more greases, industrial oils and marine lubricants. The rise in consumption levels of these base stocks is due to increasing industrialization in Asia-Pacific and other developing economies. ExxonMobil predicts demand for the extra-heavy neutral base stocks will remain robust through 2040.