Recovery of base materials from geothermal brines

Patent · Tue Jul 20 00:00:00 EDT 1993

OSTI ID:6286057

Duyvesteyn, W P.C.

A process is described for the recovery of substantially pure Zn from a reservoir of geothermal brine confined under pressure at elevated temperature at subterranean levels, the brine also containing recoverable and mounts of lead and silver which comprises: tapping and bringing to the earth's surface a portion of the geothermal brine; allowing the brine to flash at atmospheric pressure to produce steam for use in the generation of electrical power; cooling the flashed brine; extracting Pb and Ag from the brine by cementation by adding a metal selected from the group consisting of Zn, Fe and Al to the cooled brine, removing the cemented Pb and Ag from the brine by solid/liquid separation; mixing the brine impoverished in the Pb and Ag with a substantially immiscible anionic solvent selective to the extraction of Zn to produce a spent brine and a Zn loaded anionic extractant; the anionic solvent being dissolved in a diluent of water immiscible organic solvent, recycling the spent brine to the reservoir of geothermal brine; subjecting the Zn-loaded anionic extractant to mixing with an aqueous solution to produce a Zn-loaded aqueous Zn chloride solution, separating the Zn-loaded aqueous solution from the anionic extractant, adjusting the pH of the Zn-containing aqueous solution, if necessary, to a pH sufficient to promote the separation of the Zn by cationic extraction, subjecting the Zn-loaded aqueous solution to extraction with a cationic solvent selective to Zn; the cationic solvent being dissolved in a diluent of a water-immiscible organic solvent, stripping the Zn from the loaded cationic extractant using a sulfuric acid electrolyte solution, the volume ratio of the cationic solvent to the sulfuric acid solution being such as to provide a Zn electrolyte solution of Zn concentration sufficient for the recovery of Zn therefrom, and then electrowinning the Zn from the electrolyte solution to provide a product of substantially pure Zn.

• Assignee: BHP Minerals International Inc., Sunnyvale, CA (United States)
• Patent Number(s): US 5229003; A
• Application Number: PPN: US 7-763446
• OSTI ID: 6286057
• Resource Relation: Patent File Date: 19 Sep 1991
• Country of Publication: United States
• Language: English

Related Subjects

15 GEOTHERMAL ENERGY
GEOTHERMAL FLUIDS
MATERIALS RECOVERY
LEAD
SILVER
ZINC
BRINES
COOLING
ELECTRODEPOSITION
GEOPRESSURED SYSTEMS
GEOTHERMAL POWER PLANTS
GEOTHERMAL WELLS
SEPARATION PROCESSES
SOLVENT EXTRACTION
DEPOSITION
ELECTROLYSIS
ELEMENTS
ENERGY SYSTEMS
EXTRACTION
FLUIDS
LYSIS
MANAGEMENT
METALS
POWER PLANTS
PROCESSING
SURFACE COATING
THERMAL POWER PLANTS
TRANSITION ELEMENTS
WASTE MANAGEMENT
WASTE PROCESSING
WELLS
150700* - Geothermal Energy- Products & By-Products