Shell Refining & Marketing Co. has changed the blend of its premium grade gasoline in 10 U.S. metropolitan regions.
It's part of industry's first large scale effort to market a summertime product that reduces air emissions and can be used in all automobiles.
Shell's product, SU 2000E, reduces hydrocarbon vapor and carbon monoxide emissions by replacing the butane content with methyl tertiary butyl ether (MTBE). Shell might later expand the conversion system-wide, depending on customer acceptance.
Steven L. Miller, president of Shell R&M, said premium grade gasoline was chosen for the reformulation because it can be used in the entire automobile fleet.
The regions where the new blend is sold are Los Angeles, New York City, Chicago, Houston, Milwaukee, Baltimore, Philadelphia, San Diego, Hartford, and Washington, D.C. It currently is available only at Shell owned stations.
Shell earlier this year began a methanol/gasoline fuel test program in California (OGJ, Feb. 12, p. 22).
SU 2000E'S BLEND
Miller said SU 2000E's Reid vapor pressure (Rvp) will vary depending on the market area, but it will be at least 1/2-2 psi Rvp below the legal limit. The summertime Rvp, which meets most of California Air Resources Board's proposed 1992 standards, will range from 8 psi to 8.5 psi, depending on area.
Miller said SU 2000E will contain at least 5.5 vol % MTBE and the same octane number of 92-93 (R+M)/2 and proprietary detergent additive as SU 2000.
Shell figures summertime hydrocarbons and CO emissions will decline 82.3 tons/day in the 10 metropolitan regions, assuming current customers continue to buy Shell's premium unleaded gasoline. Nitrogen oxides emissions, on the other hand, will grow 1.6 tons/day because of the higher oxygen content of the blend. Aromatics and olefin levels of the gasoline were not changed.
Shell hired Systems Application Inc., San Rafael, Calif., to perform modeling studies on the new product. The studies showed that total emissions are reduced by 80 tons/day - hydrocarbons down 16 tons/day, CO down 66 tons/day, and NOx up less than 2 tons/day.
The model, which takes into account fleet characteristics, fuel volatility, and atmospheric conditions unique to each area, assumes the sales volume of SU 2000E is the same as current sales to Shell's premium gasoline customers.
In Houston and Los Angeles, where the SU 2000E vapor pressure is 1 psi below the legal standard, there is a 10% reduction in vehicle hydrocarbon emissions.
SU 2000E is produced in Shell's refineries at Norco, La., Deer Park, Tex., Wood River, Ill., and Wilmington, Calif., where modifications were mostly limited to tankage, storage, blending operations, and distribution.
Shell has no MTBE production capability. Miller said the company continues to study the economics of building capacity but currently buys its MTBE. Butane backed out of the blend will be used as refinery fuel and petrochemical feedstock.
REASON FOR CHANGE
Shell hopes to gain market by offering the first product for all automobiles that reduces some air emissions.
Shell Oil Co. Pres. Frank H. Richardson said, "This new gasoline reflects Shell's commitment to make environmental considerations a priority in development of our new products and processes.
"We do not view SU 2000E as a total solution to our nation's air quality problems. We do believe, however, it is an important step in the right direction."
Although the new product costs 2cts/gal more to produce, Richardson said, it will be priced competitively in the market.
Premium grade unleaded gasolines generally provide refiners/marketers a higher margin than midgrade and regular grade gasolines.
Nine of the 10 regions where the product is sold were identified by President Bush as having the most severe ground level air quality problems in the U.S. The exception is Washington, D.C.
SU 2000E sales in the 10 markets are projected to be more than 3.5 million gal/day, which represents 35-40% of Shell's total premium gasoline sales nationwide and about 13% of Shell's total gasoline sales.
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