The fractionation tower is used to separate products at low pressure so that less energy is required in their further processing. The tower is approximately 50 metres high, almost 11 metres wide and weighs about 400 tonnes – similar to a fully loaded Boeing 747. Hoisting it into place was a huge operation that took approximately three hours. The tower was first lifted from a horizontal to a vertical position and then placed on a 30-metre high concrete ‘frame’ by a caterpillar crane.
Improved energy efficiency
Involving an investment of over a billion euros, the hydrocracker unit has enabled ExxonMobil to strengthen the leading position of the Rotterdam refinery in the European oil industry. The refinery was already one of the most energy efficient in Europe, and this investment will improve energy efficiency by another five per cent.
Safety and efficiency gains
The vacuum fractionation tower arrived at the refinery's ‘laydown area’ (a safe zone outside the construction site) by ship in October 2016. Work on the tower immediately started after its arrival: platforms, 13 tonnes of pipelines, insulation, two kilometres of cables and instrumentation were added. Although this approach led to heavier lifting work, it also allowed for significant safety and efficiency gains. The amount of work that had to be done at height was minimised - the top platform is more than 60 metres above the ground – and carrying out the fitting work in the ‘laydown area’ was less complex than it would have been on the construction site.
Cleaner end products
The new hydrocracker unit is able to convert heavier grades of crude into cleaner end products, such as high quality base oils for a new generation of lubricants and ultra-low-sulphur diesel. Using technology developed and patented by ExxonMobil, the Rotterdam refinery will be the first in Europe to produce EHC™ Group II base oil.
Approximately 650 ExxonMobil personnel and many other people from subcontractors and service providers work at the refinery every day. During the three-year construction period, an average of more than 600 extra people were working on the site each day, with peaks of up to 1300 people in 2017. From 2019 onwards, the new hydrocracker unit will provide about 40 additional jobs.