Reconstruction of the Hydrocracker unit

Hydrocracker complex - implementation of the hydrocracking process (HVGO) of heavy vacuum gas oil under license UOP. The objective was to deepen the refining of crude oil to produce light petroleum products (gasoline, diesel).

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End user:
Naftan refinery
Novopolotsk, Belarus

The project followed the first phase of the reconstruction of this complex of the Belarusian Naftan refinery, where UNIS acted as the general designer in cooperation with Koch-Glitsch and Gicotechnica in 2002-2004.

Thanks to Hydrokrak, Belarus received a unique product during this period - diesel fuel meeting the Euro-5 standard. In 15 years, more than 7 million tonnes of diesel fuel have been produced here. The completed second phase of the reconstruction in September 2021 was based on the UOP licence as well and increased the capacity of the Hydrocracker by 25%, from the original capacity of 112.5 t/h of heavy vacuum gas oil to 142.2 t/h.


UNIS acted as the general contractor and designer for this phase of the project. The project started with the preparation of the engineering survey and inspections, continued with the preparation of the technical solution and design documentation and the supply of the complete equipment / materials. Pre-assembly and construction works have been underway since 2020. This was followed by the check of the installed the equipment and author's supervision. In April 2021, a scheduled shutdown of the entire hydrocracker complex took place, during which the technological modifications of the reconstruction were implemented. The hydrocracker complex was successfully commissioned in autumn 2021.

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The hydrocracker reconstruction project included three stages. The first was construction and installation work in the existing production environment. As hydrocracking is carried out under high pressure (5 - 20 MPa) and with a large amount of explosive substances, safety is a major concern. Some buildings important for the production process in the complex had to be rebuilt. These included a back-purification unit, a deaeration unit for the chemical water treatment plant, a new pumping unit for the supply of raw materials, an additional ammonia combustion unit, and the KP-2A electrical substation, whose capacity will improve the reliability of the power supply to Hydrocrack and other plant facilities.
With the completion of the ancillary works, the second and third stages of the reconstruction began, when the complex equipment was temporarily removed from the process chain. In a short period of time, measures were taken to coordinate the technological schemes, replace the equipment and the commissioning.


After the modernisation of the hydrocracking technology scheme, the production of diesel and kerosene increased. In addition, a completely new feedstock - heavy vacuum gas oil from the delayed coking unit - can be processed in the complex's facilities. And high-quality by-products continue to be provided in large quantities, i.e. - hydrotreated refined residues for paraffin oil production, components of base lubricating oils, liquefied gas and gasoline.