The Energy Alternatives: Extreme Petroleum — Parts 4 thru 6

The Energy Alternatives: Extreme Petroleum II

By S. Thomas Bond, Lewis County, WV

PART IV

Before we start the second part of Extreme Petroleum we must define an important ratio qualifying the utility of an energy source. It is energy return for energy invested, referred to as EROEI. It is simply how much energy you produce from a source for each unit of energy put into obtaining that energy. For example Wave power returns about 15 units of energy for each unit expended in getting it. This has to do with economics indirectly, and applies only to energy. If you are considering organic compounds, there are many other uses involving higher value than burning them for energy, feedstocks for producing chemicals being among the most conspicuous.

I am indebted to Richard Heinberg and Jerry Mander for the numerical data used in this article, from “Searching for a Miracle: ‘Net Energy’ Limits & the Fate of Industrial Society.”

At a EROEI ratio of less than 1:1 there is a loss of energy, and thus the process is not feasible as a way to get energy. A 10:1 gain is the lower edge of comfortable. For comparison, here are a couple of figures important in our national energy program. Coal returns about 50:1 and ethanol from corn is marginal, probably between 1.1 to 1 and 0.9 to 1. More about that below.

PART V

The next form of extreme petroleum we will look at is tar sands. It is soil mixed with a heavy, sticky hydrocarbon tar. Canada and the former Soviet Union are believed to be able to produce 300 million barrels of “oil” from their deposits and Columbia, South America, also has large deposits.

Tar sands may be strip mined, the product requiring subsequent processing with steam. Deeper deposits are recovered from wells which must be stimulated with injection of steam by other wells, a method called “recovery in situ.” Vast amounts of water are required, which presents a gathering problem. Strip mined tar sands after processing have about the same volume as the original deposit and must be disposed of back on the surface. The petroleum produced is heavy oil and requires additional processing for use as fuel, and it must be diluted with lighter hydrocarbons before it can be transported by pipeline. At present, one million barrels a day, 40% of Canada’s oil production is from tar sands. The product is referred to as “synthetic crude oil.”

Huge environmental problems are involved. Much land is disturbed, much water is required, several barrels for each barrel of “oil,” but some of the water can be reclaimed. Air pollution and wildlife are also affected.

The Keystone XL Pipeline, hated for its effects on farmers and ranchers, and on the environment, is designed to transport the tar sands “oil.” The 1,700-mile, $7 billion project would bring 700,000 barrels of carbon-heavy tar-sands oil per day from the Athabasca tar sands of North Eastern Alberta, Canada, to Houston and Port Arthur on the U. S. Gulf Coast. Numerous leaks have been a problem with parts already built. Tar sands have an EROEI of 5.4 to 5.5:1.

PART VI

Shale oil, another form of extreme petroleum, is produced from oil shale, a greasy rock, primarily by heating it. This converts the kerogen, the organic material in the rock, to a kind of oil and to gas. This process has been used for a long time, at least 700 years, long before modern petroleum recovery began.

Today most shale oil is produced from shale removed from the ground and taken to a retort. There it is heated to temperatures in the neighborhood of 900 degrees Fahrenheit.

The yield is low, 10% of product by weight being a very good result. It is so thick it can not be transported in pipelines without additional treatment. And the shale residue after the oil is taken out is both bulkier than the original shale input and has toxic heavy metals and organic compounds activated so they can leach out when it rains.

Typically, the product includes sulfur and nitrogen, which cause air pollution, sometimes also arsenic and iron. Particulates are a problem. Extensive upgrading, including adding hydrogen to the molecules, is required to bring the oil to standards required for transportation.

Several companies are working on processes to recover the oil by wells from the ground, so it doesn’t have to be removed and transported. These processes haven’t been advanced enough to consider any environmental problems that might be connected. The national Oil Shale Association claims “The three states of Colorado, Utah and Wyoming contain an amount of shale oil that is comparable with the conventional oil reserves in the Middle East.”

Thus reserves are substantial, especially in the U. S., but in March 2011, the United States Bureau of Land Management called into question proposals in the U.S. for commercial operations, stating that “There are no economically viable ways yet known to extract and process oil shale for commercial purposes” [for fuel]. The EROEI is 1.5 to 4 : 1, a marginal way to produce energy at best.

Parts VII thru X are to follow on tomorrow.