Inside Fracking Fluids (Feb Materials World)
The article on the possible dangers of additives to fracking fluids, gave a brief mention of the most important additive, “fracking sand” which makes up to 10% of what is pumped down to the shale layers. In the context of the article, this was understandable. Sand is not toxic, although silicosis is a potential hazard to the blue collar guys doing the mining and rock crushing.
But to those in the fracking industry, and to readers of Materials World, sand is the most important constituent of fracking fluid, it being a surprisingly costly mineral. Fracking companies have been paying up to $300 a ton at the well head. Rather than being a grit, grains of fracking sand have to be like mini-ball bearings. The best size range is from 0.4 to 0.8 mm. enabling the fracking fluid to carry the sand to where it is needed. The demand from the shale oil and gas industry is vast. In the USA, ten thousand ton train loads of sand are regularly transported hundreds of miles to the oil and gas fields. New rail heads have had to be built to service mines and sand processing centres.
What is the situation over in Britain? Fracking sand in North America is derived from rock formations that are, effectively, the fossilised remains of deserts from ages past. We have these in Scotland (not again…they have got the oil, gas, wind and hydro already!) but in the panic to “grow” shale oil and gas, will we bringing in ship loads of this vital material from the USA? Perhaps some of your mining and minerals specialists could comment?
Dr Fred Starr FIMMM, C. Eng
In the July issue of Materials World , Philip Crowson, Honoury Prof , Centre for Energy, Petroleum and Mineral Law and Policy, University of Dundee has backed up what I wrote. He points out that as a result of the demand for fracking sand, extraction in the USA soared from 6 million tonnes/annum in 2007 to 54 m tonnes in 2014.
He also calculated that on average about 90kg of sand will be needed for each tonne of oil equivalent. British sand extraction is 4 million tonnes per annum, currently. Crowson points out the aversion of the public to new quarries.
On Crowson’s figures, even a relatively modest fracking industry of 20 million tonnes of oil or gas a year, would require a 50% increase in sand extraction.