Hydraulic fracturing and the chemicals used

Hydraulic fracturing has been used in the oil and gas industry for more than 50 years and in Australia for several decades.

when drilling wells, grout or cement is pumped between the well casing (a steel tube) and the hole back to the surface. This forms a barrier between the coal seams and any nearby aquifers.

Hydraulic fracturing involves mostly water and sand that is injected into wells at high pressure to crack the coal seams so gas can flow more freely. The sand holds open the cracks. The process is designed to only affect the target coal seam. Like farmers who use chemicals on crops, QGC uses chemicals with extreme care.

The small proportion of chemical additives in hydraulic fracturing fluid are needed to reduce friction, remove bacteria, dissolve some minerals and enhance the fluid’s ability to transport sand. They consist mainly of commonly used compounds like:

• Surfactants (in soap or toothpaste)
• Guar gum (in ice cream)
• Sodium hypochlorite (in swimming pools)
• Hydrochloric acid (also in swimming pools)
• Acetic acid (basis of vinegar)

All chemicals are handled according to strict procedures by trained personnel and are used in concentrations so low as to cause no adverse environmental impact. The chemical product safety data sheets (SDS) are supplied in Table 1 below. Table 2 provides stimulation chemical risk assessments, prepared by an independent and qualified consultancy, that:

• identify the hazards associated with proposed stimulation chemicals;
• consider potential exposure pathways and the risk of potential impacts; and,
• determine the required management measures.

Chemicals Used in Hydraulic Fracturing

Service Company Name or Handling Name (links to SDS)	Main chemical components	Common uses	Main CAS#
Function: Biocide	-	-	-
BE-09	Tributyl tetradecyl phosphonium chloride	Biocide used industrial cleaning, oil field waters, papermaking	81741-28-8
BE-6	Bronopol	Eliminates bacteria in water	52-51-7
Magnacide 575, M298L	Tetrakis (hydroxymethyl) phosphonium sulfate	Eliminates bacteria in water for farming uses	55566-30-8
M275, BPA68915	3:1 CIT/MIT biocide, Magnesium Nitrate	Eliminates bacteria in water	55965-84-9
Sodium Hypochlorite, BE-7, M091	Sodium hypochlorite	Household bleach, disinfectants	7681-52-9
M300A	Glutaraldehyde	Industrial water treatment, disinfectant	111-30-8
Clay control	-	-	-
KCL, M117	Potassium chloride	Fertilisers	7447-40-7
L071, ClayCare, ClayTreat-2C, Choline chloride	Choline chloride	Agricultural feed additive	67-48-1
Corrosion inhibitor	-	-	-
B499, Gelatine	Gelatine	Marshmallows, canned hams, desserts and dairy products, pharmaceuticals	9000-70-8
L058	Sodium erythorbate	Food additive used predominantly in meats, poultry, and soft drinks	6381-77-7
U042	Tetrasodium ethylenediaminetetraacetate	Food perservative, shampoo products, dentistry, cosmetics	64-02-8, 1310-73-2, 5064-31-3
Crosslinker	-	-	-
XLW-10A	Borax, also known as sodium borate, sodium tetraborate, di-sodium tetraborate	Detergents, soaps	1330-43-4, 107-21-1, 1310-73-2
J480	Aliphatic acid salt	Fish bait additive, food preservatives	N/A .
J610	Potassium hydroxide	Manicure treatments, hair removal, soft soaps	1310-58-3
J604	Ethane-1,2-diol, Sodium tetraborate	Corrosion protection, antifreeze	107-21-1, 1330-43-4
Gel
J580	-	Food thickening agent	N/A
J594	Carbohydrate polymer derivative	None. Considered non hazardous.	-
J596, J450	2,2',2"-nitrilotriethanol	Laundry detergents, dishwashing liquids, general cleaners, shaving cream.	102-71-6, 1330-43-4, 7699-43-6
Service Company Name or Handling Name (links to SDS)	Main chemical components	Common uses	Main CAS#
Function: Gel breaker	-	-	-
GBW-30	Carbohydrates, hemicellulase enzyme	Food additives, coffee processing	9012-54-8
J218, J479, GBW-5	Diammonium peroxidisulphate	Hair bleach, household cleaners, etching copper, printed circuit boards	7727-54-0
J134	Hemicellulase enzyme	Food additives, coffee processing	9012-54-8
J318	2,2`,2"-nitrilotriethanol	liquid laundry detergents, dishwashing liquids, general cleaners, hand cleaners, polishes, metalworking fluids, paints, shaving cream and printing inks	102-71-6
J481, J490	Sodium bromate	Hair pigments, clothes dyeing	7789-38-0
Gel stabiliser	-	-	-
J589	Propan-2-ol	Keyboard, LCD screen, whiteboard and eyeglasses cleaner	67-63-0
J511	Aliphatic polyol	N/A.	N/A.
Friction Reducer	-	-	-
FRW-16	1-Propanesulfonic acid, 2-methyl-2-[(1-oxo-2-propen-1-yl)amino], sodium salt (1:1) homopolymer	Water treatment, Thickener, Personal care products	35641-59-9
J353L	Sodium thiosulphate	Preservative, stain remover, bleach and chlorine remover	7772-98-7
J568	Butyl Diglycol	Printing ink, surface cleaners, foam fire extinguishers	112-34-5
J599	Tetraethylenepentamine	Adhesives, agriculture, veterinary and detergents	112-57-2, 4067-16-7, 112-24-3
Other	-	-	-
Nitrogen	Nitrogen	Refrigeration, supercooling, inert gas	7727-37-9
Carbon Dioxide	Carbon Dioxide	Dry ice	124-38-9
Sodium Chloride, Rock Salt, D044	Sodium chloride	Table salt	7647-14-5
Fluorobenzoic acids	Fluorobenzoic acids	Groundwater tracers	385-00-2, 445-29-4, 1583-58-0
Oxygen Scavenger	-	-	-
Oxygon	Organic acid salt	Removal of dissolved oxygen in fluids, meat processing	6381-77-7
J528	Organic polymer	Biodegradable plastics (eg. Biodegradeable plastic bags, sheets, cups)	9051-89-2
J554	Aliphatic synthetic polymer	Carpenters glue	N/A
pH buffer	-	-	-
M003, Soda Ash	Sodium Carbonate	Neutralise acids, water softening	497-19-8
Sodium Hydroxide, U028	Sodium Hydroxide	Manufacturing of paper, textiles, drinking water, soaps, detergents, drain cleaner	1310-73-2
BF-3	Sodium Bicarbonate	Baking soda	144-55-8
BF-7L	Potassium carbonate	Additive in soaps, wines, dyes, glass	584-08-7
Acetic Acid, BF10L, L401	Acetic acid	Vinegar	64-19-7
HCL	Hydrochloric Acid	Swimming pool pH control	7647-01-0
FE-300	Citric Acid	Naturally occurring in citrus fruits, flavouring, cosmetics	77-92-9
Scale inhibitor	-	-	-
L065	Calcium Chloride, 1,2-Ethanediol	Brine, desiccant	10043-52-4, 107-21-1
Surfactant	-	-	-
F112	Polyethylene glycol monohexyl ether	Cleaning fluids, paints, coatings, silk screening inks	31726-34-8
Foam Stabiliser	-	-	-
B271	beta-Alanine, N-coco alkyl derivs., sodium salts	Carwash foams	68608-68-4, 111-76-2, 67-63-0
Proppant	-	-	-
Sand	quartz	Construction	14808-60-7
Carboprop	Corundum, Mullite	Ceramics	1302-93-8
NRTCarboprop	-	-	-

Stimulation Risk Assessment Reports

Type	Title
Main text	Stimluation Chemical Risk Assmt (Golder 2014)
Addendum	Urea sulphates polymer
Addendum	Glutaraldehyde
Addendum	Butenedioic acid polymer
Addendum	Fluorobenzoic acid
Addendum	Xanthan gum, sorbitol, ethane-diol, borate
Addendum	Acetates, amines, tetrafluoroethylene
Addendum	Boronatrocalcite, fumarate, diutan
Addendum	Propenoic acid, calcium chloride, oxydiethanol

Note: The above tables are periodically updated with new chemical products and also to remove some that are obsolete. Chemical products are retained on the QGC website for at least a year following their use in hydraulic fracturing. For information about historical chemicals used in hydraulic fracturing please contact us.