WAX and ASPHALT CRUDE OILS
Petroleum crude is infinitely complex and varied. The character of crude oil depends on where it is found. Crude oil found in Pennsylvania and nearby West Virginia and Southeastern Ohio is a paraffinic crude oil, or commonly termed wax-based. In contrast, the crude oil found in California, Mexico, the Gulf Coast, Kansas, Illinois, and Canada is generally asphaltic, or asphalt-based. Yes, some crude, such as that found in the Lima field of Northwestern Ohio and Indiana, is considered mixed-based and contains significant amounts of both wax and asphalt. Even the asphaltic Gulf Coast crude at the beginning of the twentieth century contained some wax. The asphaltic Gulf crude oil exhibited different qualities than the very heavy, asphaltic California crude emerging as a huge field in the West. Variety was the rule.
The wax-based crudes of the old Appalachian field have a variety of translucent colors. On the other hand, asphalt absorbs light, and, thus, asphalt-based crudes are black, or nearly so. In the nineteenth century, each of these very different crudes presented unique problems to refiners. The wax and asphalt products manufactured as byproducts when refining these different kinds of crude oil have proven to be of immense value over the years. However, in the early years of the North American petroleum industry, this was not considered the case.
Wax was an unwanted nuisance to both the early Appalachian field producers and early refiners. The wax impeded production by inevitably clogging the wellheads, tubing and bore holes, and the gathering pipelines. Producers resorted to steam, compressed air and explosives to clear a well of the buildup of unwanted wax. In the latter 1860’s, the refiners of Pennsylvania crude who manufactured lubricating oils realized wax caused lubricating oil to gum and in cold weather prevented the oil from pouring. It was evident to refiners that the pour point of lubricating oil could be lowered and that performance improved generally by removing the wax. After the light naphtha and kerosene fractions were removed, oil refined from the intermediate and heavy Pennsylvania fractions was stored in barrels or tanks in the winter outside when the temperature was below 40º F for ten days. Ice houses were also used for this purpose. The chilled, refined oil was poured into cotton bags and pressed to remove the lubricating oil stock. What remained in the cotton bag was the wax. The best refiners, such as Samuel Downer, by the end of the 1860’s were getting 7 to 10 pounds of wax from a barrel of Pennsylvania crude.
Removing the wax was costly. Early refiners incurred this cost to produce better lubricating oil. With the increased demand, however, for lubricating oil from petroleum, the supply of wax obtained from petroleum also increased. Early markets for wax had been created by the coal oil refining industry and soon wax from crude oil was competing for the wax market. What was seen as a nuisance in 1860 was considered a valuable byproduct at the end of the decade.
A relatively heavy, mixed-based crude was discovered in Northwestern Ohio in 1885 near Lima. This nineteenth century field proved to be of great value to the industry, but it was perceived initially as something of a disappointment, and Lima crude sold for substantially less than the lighter, paraffinic Pennsylvania and West Virginia crude oil. The Lima crude contained significant levels of sulfur in its complex oil molecules. Kerosene initially refined from Lima crude had a foul odor, smudged the lamp chimney and caused the lamp wick to crust. After an acceptable refining process was devised, the kerosene yields from Lima crude remained substantially less than that of Appalachian crude. It was also impossible at the time to obtain acceptable lubricating oil from Lima crude because the sulfur could not be totally eliminated. Much of the mixed-base Lima crude was used as fuel oil in industrial boilers.
Asphalt exists in natural deposits in California. In the 1860’s, it was being mined and a variety of uses were tried including road paving. California natural asphalt was used widely throughout California and on the East Coast throughout the end of the nineteenth century. The production of the California asphalt mines suggested any crude oil found in the state would be asphaltic. When the California oil field emerged as a new giant in the 1890’s and the Gulf Coast field was discovered at the beginning of the twentieth century, both fields produced a heavy, black, asphalt-based crude oil. Both crudes sold for substantially less than the eastern crudes and like the Lima crude were used extensively for fuel oil. By 1902, both the California and Gulf Coast crudes were being processed to produce refined asphalt. Small refiners produced the 29,000 tons of asphalt refined in 1902. In 1903, both The Texas Company and Gulf Oil began producing refined asphalt from Gulf Coast crude. In 1907, the Texas Company, Gulf Oil and Sun Oil each produced 25,000 tons of refined asphalt from Gulf Coast crude oil. Nationally, total production of refined asphalt in 1907 reached 138,000 tons, the first year refined asphalt production exceeded the production of natural asphalt. The market for refined asphalt grew with the growth of the American automobile industry and the North American highway system. Refined asphalt became a valued byproduct of the industry.
Very different in their character and personality, the wax-based and asphalt-based crudes of North America in time found valuable uses for their differences.
by Neil McElwee, 2008
Sources:
Rintoul, Drilling Through Time, Sacramento, 1990
Williamson and Daum, The American Petroleum Industry, The Age of Illumination, 1859-1899, Evanston, 1959
Williamson, Andreano, Daum and Klose, The American Petroleum Industry, The Age of Energy, 1899-1959, Evanston, 1963