Published May 2000
Petroleum refiners have been moving toward a strategy to upgrade low-value fuels to higher value-added petrochemical feedstocks because of a desire to improve refining profitability and comply with environmental regulations. Producing aromatic feedstocks (mainly benzene, toluene, and xylenes) seems to be a natural fit with the refining business. Benzene, toluene, and xylenes (BTX) recovery may also be part of a refinery's overall strategy to meet tighter gasoline specifications, e.g., U.S. reformulated gasoline (RFG) limits of 1% benzene and about 25 wtl% total aromatics.
This Review analyzes profit margins for refinery-based BTX production between 1985 and1998, encompassing two economic cycles. Unlike refinerylolefins integration, which improves refinery profitability with production of ethylene and propylene, reformer/aromatics integration not only has not improved refinery profitability, it subjects the refinery to greater volatility in earnings. In fact, each additional step in the integration decreased the instantaneous return on investment (ROI), except during the late 1980s and mid-1990s.
Timing is crucial to the success of launching an aromatics complex. The pay back period (before taxes) ranged from 2 to 3 years for p-xylene capacity that started up during periods of supply/demand squeeze, to more than 5 years for units that started up during periods of over capacity.