Utah’s tar sands
By mike duncan
Mar 09 2011
Salt Lake Tribune
Tar sands are no longer a what-if. This water-intensive mining may be coming to Utah soon, and what it could become is a big deal indeed.
Unlike gas wells, extracting oil from sand is neither quiet nor unobtrusive. Despite admirable efforts to minimize water use and reduce water pollution, the industry uses considerable water and generates wastes, especially if pipelines are built and field refineries established to avoid trucking the thick oil.
It is estimated that making usable oil from tar sands consumes four barrels of energy to make 10 barrels of synthetic crude, generating greenhouse gases in the process. It 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, it might supply a few percent of our daily oil consumption. It might also depress the rising price of gas a bit. It will generate well-paying jobs and tax revenue for cash-strapped governments.
It will also compete with renewable energy for public subsidies. We will not 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.
Barring the unlikely success of an appeal from organizations that include Living Rivers of Moab, 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-feet deep mine on state-owned land atop East Tavaputs Plateau. If successful, in 10 years it could apply for 2,000 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 it plans to strip mine and proudly points out that it uses less water and energy than the process 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 called a bitumen, heavier and more viscous than Canadian tar sands, and more difficult to separate from sandstone. Citrus oil, ideally 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 where it is skimmed off.
While citrus oil is a hydrocarbon solvent, one part surfactant per 200 parts oil is added as well; it is Witconate P-1059 made by Akzo Nobel Surface Chemistry Corp., a Swedish company. EER doesn’t discuss where the surfactant goes when the oil and water mixture settles. It appears that it could end up in damp reclaimed sand unless removed otherwise. Its data sheet says it’s moderately toxic to aquatic organisms. In toxicology, concentration is everything, so it’s not clear if it’s 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, an 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 redeposited in the ore body. The citrus oil is distilled from the bitumen and recycled, another energy-intensive step.
What’s left — bitumen — must be heated to get it into barrels for trucking to a heavy oil refinery and heated again to get it out. As in Canada, bitumen must be upgraded to make synthetic crude oil, and upgrading requires roughly 17 percent of a barrel of energy. It uses water as well to cool the porous coke to get it in and out of transportation carts.
All of this, then, to recover what nature didn’t finish cooking. 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 contributor to Writers on the Range, a service of High Country News (hcn.org). He is a former aerospace engineer now living in Moab.
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