TWO NEW UNITS CUT REFINERY COSTS AT PUERTOLLANO

Repsol Petroleo SA has cut gasoline production costs at its 135,000 b/d Puertollano, Spain, refinery.

The company attributes the first half 1992 cost reduction to use of process technologies licensed from Phillips Petroleum Co.

With installation of Phillips' hydrofluoric acid (HF) alkylation and Hydrisom technologies, Repsol no longer has to import methyl tertiary butyl ether and run its platformers at maximum severity.

Repsol said its new HF alkylation and Hydrisom units permit the refinery, 240 km south of Madrid, to produce all of its own base gasoline and motor fuel blending agents.

The licensed processes also allow Repsol to upgrade its products to meet European Community environmental standards and satisfy growing demand for high octane unleaded gasoline. The refinery is using the new units to produce an alkylate additive of more than 97 research octane number (RON) and about 94 motor octane number (MON) to increase the octane of motor fuels and meet Spanish limits on lead.

Refiners in the U.S. can average RON and MON standards for acceptable "pump octane" numbers, Phillips said. In Europe, however, each standard must be met individually.

Before adding the 3,500 b/sd HF alkylation unit, Repsol had to produce gasoline with higher RON than required in order to meet minimum MON standards, again increasing operating costs.

Using the HF alkylation process, Repsol now can meet new gasoline environmental standards and market demands throughout Europe by:

Reducing lead in premium (97 RON, 87 MON) and regular (92 RON, 82 MON) gasoline to 0.15 g/l. from 0.4 g/l.
Increasing production of premium gasoline.
Increasing production of Eurosuper unleaded gasoline (95 RON, 85 MON) while decreasing overall production of leaded gasoline.

The Phillips Hydrisom unit prepares HF alkylation reactor feedstock from butenes produced in the refinery's fluid catalytic cracker, coker, and steam cracker units and then processed in an upstream MTBE unit. The Hydrisom process enhances the alkylation feedstock by upgrading C4 hydrocarbons from these units by hydrogenation and isomerization.

During installation, Repsol engineers also proved the efficiency of the alkylation unit's rapid acid transfer system. The system is designed to move hydrofluoric acid to a secure storage tank quickly in the event of an unplanned release.

Prior to the unit start-up, engineers activated the acid transfer system. Repsol engineers said transfer to the gravity fed secure storage tank was carried out in less than 7 min, well within design limits.

Phillips developed the basic engineering design package for fabricating the units. Detailed engineering was done by Tecnicas Reunidas in Madrid.