The oil and gas drilling industry uses calcium zinc, and sodium bromides to prepare high-density, clear drilling fluids. These brine fluids are used in deep, high-pressure oil and gas wells; they do not plug the formation in workover and completion operations, as conventional drilling muds can do. Such bromide salt brine usage led to higher production rates and longer production lifetimes. Calcium bromide is the most popularly used, with zinc and sodium bromides following closely.
Calcium Bromide:
A clear brine fluid, Calcium Bromide (CaBr2) solution is used as single salt brine in densities ranging from from 11.7 lbs/gal to 15.1 lbs/gal. It is used as a completion, workover, gravel pack, and packer fluid. It can also be used as a spike fluid to increase density in fluids up to 14.2 lb/gal. Due to its inhibitive properties, CaBr2 can help reduce formation damage induced by clay swelling and dispersion. CaBr2is becoming a popular choice in oil and gas drilling, it is, in fact preferred over many other fluids because it mixes easily with all the major zinc and calcium based brines, adjusts the density of other brine systems, is chemically and thermally stable, and is absolutely non-damaging to formation.
Sodium Bromide:
Sodium Bromide (NaBr), a salt is used alone or in a combination with sodium chloride or zinc bromide to form clear workaround and drilling fluids with densities of 8.4-12.5 lbs/gal. Non-damaging to the formation, it can be mixed with other solutions of bromide and chlorides. It is especially useful when used in formations that are known to have sensitivity towards calcium. When chloride ion is not desirable and when calcium may not be the preferred choice. It is extensively used in situations where formation of waters contains high levels of sulfate or carbonate that may precipitate with the calcium ion.
Zinc Bromide:
Zinc Bromide is a clear, solid-free brine fluid with minimum density of 19.2 lbs/gal. It is used in completion fluids and offers features and benefits like it is non-damaging to the formation, it is thermally and chemically stable, and It can be blended with other solutions containing bromides and chlorides. It can be used with other bromides and chlorides to prepare non-damaging liquids with densities ranging from 15.1 lbs/gal to 19.2 lbs/gal. It can never be produced as dry material in sufficient quantity to be used in the completion fluid market it can be prepared only as a liquid brine.
These bromide based completion fluids are used in both offshore and onshore drilling operations. Recent expansion in drilling activity like deep, high pressure wells have contributed to the rapid growth in this market, accounting to an expected growth from $10.86 billion in 2013 to $18.37 billion by 2020, with a CAGR of 7.8 percent.