Patent ID: 6939483

Claim:
A corrosion resistant brine fluid comprising: water; a source of water soluble cations where the cations are selected from the group consisting of sodium, calcium, zinc, ammonium, rare earths, and mixtures thereof to form a brine with the water; and an additive present in a concentration ranging from about 0.05 to about 2.0 moles of additive per mole of cation, in the absence of added arsenic; where the density of the brine is at least 11 pounds/gal (1.3 kg/l), and where the additive is selected from the group consisting of ammonia, hydrazine, azoles, piperidines, piperizines, azindines, azides, betaines, amino acids, guanidines, salts of hydrazine, azoles, piperidines, piperizines, aziridines, azides, betaines, amino acids, ureas, guanidines, thereof, and mixtures thereof.