Abstract: This invention relates to a hydrometallurgical process for the treatment of mercury contaminated muds. More particularly, this process pertains to a hydrometallurgical process for the treatment of Environmental Protection Agency designated K106 muds discharged from a mercury chlor-alkali plant.

Abstract: This invention relates to a hydrometallurgical process for the treatment of mercury contaminated muds. More particularly, this process pertains to a hydrometallurgical process for the treatment of Environmental Protection Agency designated K106 muds discharged from a mercury chlor-alkali plant.

Abstract: A method to detoxify municipal sewage sludge containing heavy metals comprises the steps of mixing sewage sludge, at least one catalytic oxidant such as a ferric salt, at least one regenerative oxidant and an acid to form a reacting slurry having a solids fraction and a liquid fraction and, after a suitable retention time, separating the solids fraction from the liquid fraction. The reacting slurry is maintained during its retention time at a pH range between approximately 1.0 to 2.0 and at an oxidation reduction potential of, at least, +400 milivolts. The heavy metals originally absorbed into the solids fraction of the sewage sludge solubilize into the liquid fraction of the reacting slurry. Thereafter, the reacting slurry is discharged into a conventional solids/liquid separating device so that the metal-laden liquid fraction becomes separated from the solids fraction which is now substantially bar ren of heavy metals.

Abstract: Brine containing at least two salts, one or more of the salts having a higher hydrated form and a lower hydrated or anhydrous form, is fed to a non-convective solar pond and one of the salts having a higher hydrated form and a lower hydrated or anhydrous form is crystallized in a higher hydrated form, dehydrated to a lower hydrated form, and recovered from the bottom of the pond in solid, pure form essentially free from the other salts in the brine. To effect separation, the salt having a higher hydrated form and a lower hydrated or anhydrous form, which is to be recovered in pure form must be present in the pond in an essentially saturated concentration. The concentrations of any of the other salts must generally not exceed saturation concentration at the temperature in the top layer of the pond, and must not exceed saturation concentration at the conditions in the bottom layer of the pond. Concentrations of other salts in the pond must be controlled such that the required density gradient is maintained.

Abstract: Mined salt mixtures comprising sodium-carbonate, -bicarbonate, -chloride, -sulfate, and -double salts, such as trona and burkeite, are leached with a bicarbonate-saturated solution and added carbon dioxide to selectively dissolve the sodium chloride, sodium sulfate and burkeite and to precipitate additional trona, leaving a leach residue consisting essentially of trona. The trona is calcined and dissolved, and the carbonate solution is purified, crystallized and dehydrated in a non-convective solar pond yielding high purity sodium carbonate monohydrate which is converted into dense soda ash. The brine solution from the leach may be treated for the recovery of a further amount of trona.