Why bother cooking what nature failed to finish?
by Mike Duncan
Tar sands are no longer a what-if. This water-intensive form of mining may be coming to Utah soon, and what it could turn into is a big deal indeed.
Unlike gas wells, extracting oil from sand is neither quiet nor unobtrusive. Despite the industry's admirable efforts to minimize water use and reduce water pollution, the process uses considerable water and generates wastes, especially if pipelines are built and field refineries established to avoid the need to truck the thick oil elsewhere.
It is estimated that it takes the energetic equivalent of four barrels of oil to make 10 barrels of synthetic crude from tar sands. The process generates greenhouse gases, and it also requires a huge infrastructure to supply that up-front energy and transport the oil out.
Of course, we need oil, and as a statewide industry, tar sands might help supplement our daily oil consumption -- perhaps by a few percent. It might also depress the rising price of gas a bit. It will definitely generate some well-paying jobs and tax revenue for cash-strapped governments.
It will also compete with renewable energy for public subsidies. We will not be able to tell Saudi Arabia to get lost. A lot of rural country, some of it in or near spectacularly scenic areas that attract cash-laden tourists, could eventually be transformed into open pits, refineries and rolling hills of porous beach sand covered by a thin layer of topsoil whose reclamation will be neither easy nor quick.
Living Rivers of Moab and other organizations have fought to stop the project, but barring their appeal's unlikely success, Earth Energy Resources, a small Canadian company, will eventually get its permit from the Utah Division of Oil, Gas and Mining. The company plans to develop a 200-acre, 150-foot-deep mine on state-owned land atop East Tavaputs Plateau. If it's successful, in 10 years it could apply for 2,000 more acres. The lease lies within the 225 square miles of PR Springs, one of 10 Special Tar Sands Areas designated in 1981 by Congress, back when James Watt was Interior secretary.
Energy Resources says that it plans to strip mine, but proudly points out that it will use less water and energy than is used in Athabasca, Alberta.
Here's what Earth Energy Resources plans to do: The ore, a cross between asphalt and sandstone, will be dynamited, scooped, hauled and crushed. Utah's oil sands hydrocarbon is a bitumen, which is heavier and more viscous than Canadian tar sands, and more difficult to separate from sandstone. Citrus oil, a hydrocarbon solvent ideally obtained from Brazilian oranges and lemons (according to the patent application), is added, so that the coalesced bitumen and oil is light enough to float on water once it is skimmed off.
One part surfactant per 200 parts oil is added as well; it is Witconate P-1059TM made by Akzo Nobel Surface Chemistry Corp., a Swedish company. EER doesn't say where the surfactant goes when the oil and water mixture settles. It appears that it could end up in damp reclaimed sand unless otherwise removed. The data sheet says it's moderately toxic to aquatic organisms. Because concentration is everything in toxicology, it's not clear whether this is a problem. Additionally, smaller amounts of an anti-foaming agent, Guardex PC-O-H 4625, are added, and possibly water-softening chemicals such as lime, soda ash, soda water or chlorine to control pH. The exact recipe is secret.
About 10 parts water per part oil are added and heated to 100 degrees Fahrenheit, another energy-intensive step. The resulting slurry is agitated and then allowed to settle. The water is drained, centrifuged and about 80 percent recycled, leaving damp sand with water-soluble chemicals and residual citrus oil-bitumen to be re-deposited in the ore body. The citrus oil is then distilled from the bitumen and recycled, another energy-intensive step.
What's left -- the bitumen -- must be heated to get it into barrels for trucking to a heavy oil refinery and later heated again to get it out of those barrels. As in Canada, bitumen must be upgraded to make synthetic crude oil, and upgrading requires the energetic equivalent of roughly 17 percent of a barrel of oil. The process requires water as well to cool the porous coke to get it in and out of the transportation carts.
All of this, then, to recover what nature didn't finish cooking in the first place. Is it worth it? Not in my book. Let's spend our energy development dollars on more promising technologies that leave wild country in peace.
Mike Duncan is a former aerospace engineer now living in Moab, Utah.© High Country News