Here’s a word that I’ll bet you haven’t come across before: proppants. (Although if you’ve found this post through a web search, chances are pretty good that you were looking the word up.)
At the moment, the word is still industry jargon, but it’s likely to creep further into the language. It might not ever become common, but it stands a good chance of becoming one of those words that most people understand, even if most people rarely or ever use it.
Fracking is the common term for hydraulic fracturing, a controversial technology used primarily for oil and natural gas extraction. Fracking has been in the news a lot the last few years, and by now most people have heard of it. As with any industry or technology, fracking comes with its own vocabulary, much more than a single word.
In addition to fracking and hydraulic fracturing, it’s also sometimes referred to even more precisely as hydraulic stimulation fracturing. Other related words and phrases that you’re likely to encounter around a serious fracking discussion include horizontal drilling, injection well, shale oil (and shale gas), kerogen, pyrolysis, fracturing fluid (or fracking fluid), tight oil, tar sands (and oil sands) — and probably many others. While all those words are interesting, you can guess by simple volume that it’s too much to cover with a single post. This one will only delve primarily into proppants.
Proppants (the word could arguably be a contraction of “propping agents,” but most sources suggest it was more likely coined by imitating the form of the word propellants) describes a class of substances used in fracking. In the same way that fracking isn’t a drilling technique by itself (it’s an add-on process used after a well has been drilled), fracking doesn’t work by simply pumping water (or another drilling fluid formulation) down a well and waiting for the oil or gas to flow out.
Proppants are essentially tiny pellets, often produced by a proprietary method. They might be grains of sand that have been coated with a tough resin, or they might be glass beads, or they might be micron-sized ceramic pellets. Or they might be something else. They key to an effective proppant is that it is sized properly for the particular application (to find its way into the various fractures extending from the well) and that it’s strong enough to hold the fractures open (or to actually create them under pressure) in order to improve gas extraction.
Proppants are a component of fracking fluid, regardless of the specific fracking application. Depending on the conditions and the needs, proppants will make up from less than 1% of the fluid to nearly 9%. Most of any fracking fluid (up to 99% in many cases) will simply be water, while the rest (often about 1%, and rarely more than 7%) will consist of other components determined by the geology and conditions of the site and the substance being extracted. These formula are often proprietary (trade secrets), but have been known to include substances that run the gamut from the innocuous (guar gum) through the relatively safe (methanol) and into the potentially hazardous (hydrochloric acid). Some are diesel-based, some use toxic and potentially carcinogenic volatile organic chemicals (such as benzene and toluene), and some even employ radioactive tracers (to better determine the characteristics of the drilling area). It should be stressed that those active substances are not proppants; to best fulfill their function, proppants are inert.
You’ll find an actual use of proppants here, in a good summary article on fracking that most non-specialized readers can follow.
Proppants and the other vocabulary associated with fracking are relatively new. But not as new as you might think. The technique has been used since sometime during the late 1800s (for water as well as oil), and the term fracking itself first appears in print (with this context and use) no later than 1938. The more technical term, hydraulic fracturing, began showing up in industry literature by at least the mid 1920s.
“Propping agent,” one possible source of proppant, and proppant itself, both seem to spring into existence in 1966. In that year, the words appeared in print in the Journal of Petroleum Technology, the Journal of the Institute of Petroleum, Petroleum Management, Independent Petroleum Monthly, Indian Science Abstracts, and several other publications. The words tracked together until the mid 1970s, after which proppant won out (the online data for recent years is unreliable, but hint that the words might again be seeing about equal use).
(As a side note, Google ngrams points to a use of proppants from around 1811, but doesn’t display the citation. This is so far off the mark that it’s probably an OCR error, as sometimes happens with old, scanned books.)
Note also that “fracking” shouldn’t be confused with “frakking,” one of the forms of the all-purpose swear word, frak, from the Battlestar Galactica television series (although in some people fracking has been known to produce reactions that lead to a liberal use of words similar to frakking).