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Although the United States has not built a large refinery for decades, existing processing facilities are constantly expanding their capacity in a bid to utilize the constantly increasing fuel production. Construction of major facilities is partly impossible because of tight environmental regulations, so refiners are either building small, highly specialized plants, or are looking for ways to adapt their existing refineries to higher output rates and production lines, the Wall Street Journal reported this week.

According to data gathered by the news service and consultancy IHS, U.S. refineries are projected to add capacity of more than 400,000 barrels of oil per day to operational facilities through 2018. This is roughly the capacity that a major new refinery would have, according to the news source. Capacity expansion is on the agenda for a number of large companies, including Valero Energy and Marathon Petroleum Corporation.

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A relatively new industry trend is the construction of so-called "splitters" or "toppers," which are used to process the superlight oil from the Eagle Ford Shale in Texas. Building a splitter is relatively inexpensive and the facility is not actually considered a refinery because it is not suitable for a wide range of crude types. Because crude cannot be exported from the United States, these small plants can be used to process oil to an extent that allows the refined product to be shipped to refineries in Latin America, Europe and Asia for further processing.