diesel hydrotreaters revamp a way for increasing production

44th International Petroleum Conference, Bratislava, Slovak Republic, September 21-22, 2009 2
find a solution in this tough situation the technological department and the
research laboratory made estimation about the required catalyst volume
increase necessary to achieve production of NZSD in the hydrotreating units
HDS-2 and HDS-3 running on a mixture of heavy straight run gas oil and light
vacuum gas oil from Ural crude. This estimation showed that the liquid hourly
space velocity (LHSV) should be approximately 1.0h -1 if the mixture of heavy
straight run gas oil and light vacuum gas oil from Ural crude is hydrotreated at
a pressure of 35 kg/cm 2 on the Topsoe TK-576 Brim catalyst. This catalyst
proved to be among the best performers in the ultra low hydrodesulphurization
[1,2]. The LHSV of about 1.0h -1 was possible to achieve if reactors with
dimensions of the LNB FCC feed hydrotreating reactors were installed in the
HDS-2 and HDS-3 units. Drawings of these reactors were available and this
gave the opportunity to shorten the time for their manufacture. The LNB
signed a contract with the Haldor Topsoe (HTAS) for basic engineering of
reactor section for reconstruction of the LNB HDS-2 and HDS-3 units in
November 2007. In late November 2007 HTAS assured LNB that the LNB
FCC feed hydrotreating reactors fit the reconstruction of the HDS-2 and HDS-
3 units and LNB signed a contract for manifacturing of the hydrotreating
reactors for a period of less than 12 months with the Russian company OOO
Energomash-Atomash. Having the bitter experience with appearance of
leakage in the heat exchangers LNB was aware that the production of NZSD
could fail if the older heat exchangers were used [3]. That is why a contract
with the Ukrain company OOO Mashzavod was signed for manufacturing of
shell and tube heat exchangers for utilization of the energy of the reactor
product stream effluent. The delivery term for the heat exchangers was lower
than 12 months. With this tight schedule the HDS-3 was reconstructed and
successfully started up operation in late December 2008.The HDS-2 unit was
reconstructed and successfully started up operation in early March 2009. The
aim of this work is to discuss the achieved operation of the reconstructed LNB
heavy middle distillate hydrotreating HDS-2 and HDS-3 units.
EXPERIMENTAL
The performance test of the reconstructed LNB HDS-3 was carried out in
December 2008 at following conditions:
- Feedstock properties
Density at 15 °C, kg/m3 851.6-853.5
Distillation, ASTM D 86, o C
- IBP 208-220
- 10% vol% 257-265
- 50% vol% 294-300
- 90% vol% 330-340
- 95% vol% 338-349
- EBP 355-360
Sulfur , wt% 0.66-0.875
Bromine number, g Br2/100 g 0.9-2.8
Total aromatics,% 27.4-29.2
Polynuclear aromatics , % 8.8-9.7