Mayor of Rotterdam Ahmed Aboutaleb today opened the sixth desulphurisation plant, HDS-6, at the Shell complex in Pernis. This considerably expands the capacity for deeper desulphurisation of diesel and domestic fuel in accordance with the most recent European environmental specifications. The investment of approximately 400 million euros contributes to the position of Pernis as one of Shell’s most important refinery complexes in the world. There has been close to continuous and considerable, investment since the 1980s, especially in cleaner and more flexible plants.
Shell Pernis is Europe’s largest refinery, with a processing capacity of more than 400,000 barrels of oil per day (over 44,000 litres per minute). Including the new plant, Shell captures around 450 tonnes of sulphur per day. The golden ‘syrup’ is used as a raw material in the chemical industry and the production of artificial fertiliser.
The HDS (HydroDeSulphurisation) plant removes sulphur from the heavier gas oil fractions. The desulphurised gas oil ends up in the diesel pool (the plant produces 10 ppm sulphur gas oil for this) or the domestic fuel pool (50 ppm sulphur gas oil) of Shell Pernis.
The influence of a catalyst, high pressure, temperature and hydrogen-rich gas convert the sulphur molecules in the gas oil into H2S. The H2S is separated from the gas oil elsewhere in the plant.
All this takes place with the latest technology. For instance, the plant operates at higher pressure than existing HDS plants, enabling more and deeper desulphurisation. The existing HDS plants can only desulphurise a relatively light gas oil and their catalyst has to be replaced much more frequently.
Sources: Shell and miscellaneous, 14-06-2012