CONCAWE REPORTS REDUCED EMISSIONS FROM EUROPEAN REFINERIES

Discharged Oil chart (46537 bytes) Conservation of Clean Air and Water Europe (Concawe), an organization of European oil companies, has released its most recent data on refinery-related emissions trends. In the October 1994 edition of "Concawe Review," the Brussels-based organization summarized a number of its ongoing studies in this area.

Included in the review were data on sulfur dioxide emissions and results from a survey of refinery effluent water quality. In general, refiners' efforts are reducing pollution from these sources.

SO2

Concawe has surveyed refinery sulfur balances since 1979. Its most recent survey of sulfur intake and output at European refineries gathered data from 1992.

The 1992 survey covers 85 European refineries processing 476 million metric tons/year (mty), or about 9.6 million b/d, of crude oil. These refineries constitute 81% of Western Europe's processing capacity.

Total sulfur intake for these refineries in 1992 was 5.6 million metric tons (mt). Table 1 (18666 bytes) summarizes sulfur output by category.

The most recent data reflect several important trends since the survey began in 1979:

Total crude runs had been declining sharply since 1979, but have been recovering slowly since 1985.
The percentage of sulfur in crude oil has declined from about 1.4 wt % to a little more than 1 wt %. The lowest point (slightly less than 1 wt %) was reached in 1985.
Sulfur in oil products used for combustion has decreased 60% since 1979.
Sulfur recovery in refineries has increased from slightly more than 1 million mt/year in 1979 to nearly 1.9 million mty in 1992.
SO2 emissions from refineries have declined more rapidly than crude runs, although they have remained constant since 1985, except for a slight increase in 1992.

REFINERY EFFLUENT

The discharge of oil in refinery effluent water continues to decline in Western Europe. Between 1990 and 1993, Concawe reports a 46% reduction in the ratio of oil discharged to oil processed. These figures are calculated from survey responses from refineries representing 90% of Western Europe's refining capacity.

Concawe's results also revealed:

In 1993, 2,018 mt of oil were discharged with the aqueous effluents from 95 refineries, compared to 3,340 mt from a slightly different set of 95 refineries in 1990. This decrease occurred despite the fact that 9% more oil was processed in 1993.
During the past 3 years, there has been a 40% reduction in total oil discharged.
In 1993, 3.6 mt oil were discharged per million mt oil processed, compared to 6.7 mt in 1990. This is equivalent to a 46% reduction.
Since the first survey in 1969, there has been a 95% reduction in oil discharged in refinery effluents (the 1969 figure was 44,000 mt).
Of the refineries surveyed, 85% are now equipped to biologically treat their effluents. In fact, since 1990, 5% more refineries have added these facilities, and 20 of the 95 refineries surveyed have improved their effluent treatment systems.

On the other hand, says Concawe, the volume of effluent has increased from 3.5 mt/ton of oil processed in 1990 to 4.8 mt/ton in 1993. In terms of total effluent, this is

an increase from 1,782 MMmty to 2,670 MMmty in 1993.

This increase was caused mainly by the inclusion of two refineries in the most recent survey, neither of which have responded to the survey before. Both of these refineries have once-through cooling water systems. Without the addition of these two plants, there would have been a modest reduction in total effluent. These results are encouraging, says Concawe, particularly in view of the increased complexity of refineries needed to meet increased demand for light distillates and reduced demand for fuel oil.