Hydraulic fracturing, often called fracking, provides access to valuable fluids far below the Earth’s surface such as natural gas, petroleum and brine. The method to extract these fluids involves highly pressurized liquid (fracking fluid) being forced into a wellbore and thereafter into the expansive layers of rock beneath the Earth’s surface. This creates cracks in the rock that are propped open by small particles in the fracking fluid. At that point, the desired fluids in the ground are able to escape and are harvested through the well shaft.

The small particles used to “prop” up the cracks in the rock anchor the success of the whole process. These particles, called proppants, come in a variety of forms, the two most common being sand and ceramics. Proppants are mixed into the fracking fluid and delivered with high force through the well pipeline. There, the fluid is released into the rock formations, causing the fractures.

The size and shape of the proppants used affect both the proppant suspension within the fluid (how well the particles stay suspended and don’t settle) as well as the efficacy of keeping the fractures in the rock open. Irregular sized particles often experience more breakage under the pressure of the rock formations. Conversely, perfectly spherical particles provide better load support with less collapsing.

A variety of tests are performed to find the proper size of particle in relation to the viscosity of the fluid (the thickness or flow of the fluid). The size of the particle has bearing on the proppant suspension within the fluid. Particles must be uniform in size and shape to provide the best outcome.

Attritor Grinders provide a controlled method for grinding these fracking materials. Contrary to conventional ball grinders where the entire drum rotates, these use ball bearings and an arming shaft that stirs the media in a stationary tank.

The Attritor Grinders provide increased efficiency through less energy consumption, less space needed and the ability to test and observe the grind throughout the process as a result of the open tank model.

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