AM-94-50 CATALYTIC DEWAXING OF VGO AND DIESEL AT OMV’S SCHWECHAT REFINERY

Description:

At OMV’s Schwechat refinery, a Unicracking/DW unit reduces the pour point of high- viscosity VGO by 9OoF with no reduction in viscositv. The unit also removes contaminants, yielding dewaxed products containing <20 wppm nitrogen and < 20 wppm sulfur. The first catalyst cycle lasted 4 years, with feed rates exceeding 125% 0 of design. The first run was terminated for a required inspection, not for lack of catalyst activity. In fact, during the 4-year run, Unocal’s H-80 catalyst showed no detectable activity loss. All products yields were stable throughout the cycle, as was the pour point (-4OF) of the dewaxed product. Product viscosities actually increased as the cycle progressed. During the winter months, the unit is also used to improve the pour point of diesel fuel, yielding low-sulfur products with good color (L 0.5 ASTM) and excellent stability.