Fracking Chemicals List – What’s involved and what’s dangerous

Photo by Nicholas A. Tonelli

Hydraulic-fracturing uses a great deal of water, but many other chemicals may also be involved in the fluids used for fracking. There are not large quantities of many chemicals, ranging from just 0.5 to 2.0 % of the fracturing fluid total volume, but the possible effects can still be negative on people and the environment.

• Proppants, also known as “props”, are chemicals that open the fractures and then allow the fluids or gases to flow in a freer way to the wellbore. Sand, including zirconium oxide and sintered bauxite, is used to keep fractures open, so that the gas or oil can be extracted. Ceramic beads are also a part of this mixture.
• Acid is used in cleaning intervals of drilling mud and cement before the fluids are injected. Hydrochloric acid HCL, also known as muriatic acid, is used in this process. Breaker chemicals, like Peroxydisulfates, reduce fluid viscosity so that proppants can be released into fractures. They also enhance the fracturing fluid recovery.
• Bactericides and Biocides including Gluteraldehyde inhibit the growth of certain organisms that might otherwise produce gases that could contaminate the methane gas. These also prevent bacteria growth which could reduce the fluid’s ability to carry the proppant into new fractures.
• Buffers, or pH adjusting agents, like potassium carbonate or sodium carbonate and acetic acid are able to adjust and control the pH levels of the fluid so that other additives will work properly.

• Clay controls or stabilizers, including potassium chloride and tetramethyl ammonium chloride prevent the migration and swelling of formation clays, so that they do not block pore spaces. Otherwise, they might reduce the permeability of the shale.
• Corrosion inhibitors like ammonium bisulfate and methanol help to reduce the growth of rust on the steel tubing, tanks, tools and well casings.
• Friction reducers including petroleum distillates and sodium acrylate-acrylamide copolymer allow the fluids used in fracking to be injected at the best possible rates, by lowering the amount of friction between the fluids and the piping.
• Iron control chemicals like polyacrylate, ethylene glycol and Ammonium chloride prevent any precipitation of sulfates and carbonites, so that they can’t plug off the shale formation.
• Surfactants like ethoxylated alcohol, isopropanol and methanol reduce the tension in the surface of the fracturing fluids, to aid in the recovery of the fluid.

Some of the chemicals used in fracking are toxic to the environment, as well as to humans and to wildlife. Some may cause cancer. The substances that are potentially damaging can contaminate water in the areas around the fracking wells.