INA, the Croatian subsidiary of Hungary’s MOL Group, announced on September 21, 2026 that it has begun feedstock introduction and successfully started up a newly built delayed coker unit (DCU) at its Rijeka refinery. The project, into which roughly €700 million was invested, is reportedly operating stably at around 70% of its design capacity.
The new DCU at the Rijeka refinery is an upgrading unit that cracks heavy residues to increase the yield of lighter petroleum products; INA confirmed that feedstock introduction began on September 1, 2026, and that the unit reached a stabilized operating stage through continued operation since then. The specific equipment supplier or technology licensor was not identified in this announcement.
Roughly €700 million (equivalent to about KRW 1 trillion) was invested in this project, and it is currently operating at around 70% of design capacity. When processing the same crude oil, diesel yield increases by up to 30% compared to before, and operation of this unit has reportedly fully eliminated the need to import vacuum gas oil (VGO). INA and its parent MOL Group have invested a total of €1.3 billion in refining and logistics infrastructure over the past 12 years, according to the report.
The start-up of this DCU is understood as an extension of MOL Group’s refining infrastructure upgrade strategy aimed at raising self-sufficiency in diesel and other light products across the Adriatic region, including Croatia, while reducing dependence on imported feedstock.
This case reflects a recent trend in the European refining industry of focusing on upgrading existing facilities to improve light-product yields rather than expanding new refining capacity. Because equipment investments that reduce dependence on imported VGO also connect with discussions on strengthening energy security within Europe, similar upgrading projects could follow at other refiners in Eastern Europe and the Adriatic region. The industry expects steady demand for replacing and expanding aging facilities among European refiners in the market for upgrading units such as delayed cokers. It is also worth noting how an integrated energy company like MOL Group, which holds refining assets across multiple countries, executes investments sequentially over a long period at the group level.
When this unit will reach 100% of its design capacity is of interest going forward. Which additional projects will follow among MOL Group’s announced refining and logistics infrastructure investment plans is also worth watching. Whether the spare light-product capacity secured through this upgrade will lead to expanded regional export volumes also needs to be confirmed going forward.