What is frac sand?
Silica sand or frac sand is a durable, round grain, crush-resistant material produced for use in the hydraulic fracturing process (otherwise known as fracking). This process is used to gather energy sources, such as oil, natural gas and natural gas liquids from underground rock units that lack adequate pore space for these fluids to flow into a well.
How is frac sand used?
Some subsurface rock units, such as organic shale, contain large amounts of oil, natural gas or natural gas liquids that will not flow freely because the rock either lacks permeability or the pore spaces in the rock are so small that these fluids cannot flow through them.
Hydraulic fracturing solves this problem by generating fractures in the rock. This is done by drilling a well into the rock, sealing the portion of the well in the petroleum-bearing zone, and pumping a mixture of water, silica (frac) sand and chemicals under high pressure into that portion of the well.
The chemical in the water creates a viscous gel which in turn facilitates the water's ability to carry grains of frac sand in suspension. Billions of frac sand grains are carried deep into the fractures made by this pumping action. Over one million pounds of frac sand can be used to stimulate a single well.
Where is it found?
Frac sand can be found all over the world, with sizable reserves in Italy, Australia, Turkey and Germany (see pie chart on this page). The worlds largest producer of frac sand is the US, where more than 49m tonnes was produced in 2012.
A few years ago producers in Wisconsin and Texas were supplying much of the frac sand used by the oil and gas industry. However, a huge spike in demand caused by the natural gas and shale oil boom has motivated many companies to provide this product.
Frac sand producing companies are located in the central part of the US where the St. Peter Sandstone and similar rock units are close to the surface and easily excavated yet much of the frac sand used for the oilfields is found in the Marcellus Shale, Utica Shale, Bakken Formation, Haynesville Shale, Fayetteville Shale, Eagle Ford Shale and Barnett Shale.
Who is using it?
There are many end uses for silica sand including abrasives, filtration, foundry, glassmaking and silicon metal applications. The specifications for each use differ, but silica resources for most uses are abundant.
The demand for frac sand has risen sharply in the last few years in response to numerous shale plays developing in many parts of the US. Most major silica sand producers increased production capacity as a direct result of the hydraulic fracturing boom.
Who is producing frac sand?
Major frac sand plays include:
Smart Sand Inc.
A schematic of a typical hydraulic fracturing operation, showing surface equipment and services and subsurface fracking.