Chemical use in hydraulic fracturing

Certain chemicals are needed to ensure that the hydraulic fracturing process is efficient and effective. The primary chemicals used for hydraulic fracturing operations are gelling agents, friction reducers, biocides, corrosion inhibitors, oxygen scavengers, and acids – all commonly used in other sectors of the petroleum industry and elsewhere in everyday life.

In the UK, approximately 0.25% of the total volume of fracturing fluid consists of chemicals, the rest being water (~95%) and proppant (~5%). Regulators such as the Environmental Agency (EA) and Scottish Environment Protection Agency (SEPA) require operators to disclose the chemical constituents in fracturing fluids.

In the US, the concentration of chemicals can reach up to about 2% of the total volume of fracturing fluid. The exact constitution of fracturing fluid depends on the characteristics of the formation. A growing number of states currently require operators to divulge the chemicals used; to increase transparency, most operators disclose the chemicals used through the publically available FracFocus Chemical Disclosure Registry.