Control of scale deposition in geothermal operations
AssigneeUnion Oil Company of California
InventorsDarrell L. Gallup, John L. Featherstone
Life of this patent
Estimating the term…
Abstract
Radioactivity and fluoride ion are inhibited or prevented from precipitating in scale formed from a geothermal brine by adding a scale inhibitor to the cooling brine solution. Preferred scale inhibitors include polyacrylate dispersants and phosphonomethylated amines.
Claims49
A method for treating a feed geothermal brine containing silicon-containing components and naturally occurring radioactive materials comprising:
- introducing said brine into a clarification zone in which silicon-containing components are induced to deposit by addition of a flocculating agent;
- inhibiting the deposition of naturally occurring radioactive materials in said clarification zone by introducing into said clarification zone a crystal structure modifier;
- and
- recovering from said clarification zone a product geothermal brine of substantially reduced content of silicon-containing components but containing a substantial proportion of the naturally occurring radioactive materials originally contained in said feed geothermal brine.
A method for treating a feed geothermal brine containing silicon-containing components and naturally occurring radioactive materials comprising:
- introducing said brine into a clarification zone in which silicon-containing components are induced to deposit by addition of a flocculating agent;
- inhibiting the deposition of naturally occurring radioactive materials in said clarification zone by introducing into said clarification zone a phosphono-lower-alkylated amine;
- and
- recovering from said clarification zone a product geothermal brine of substantially reduced content of silicon-containing components but containing a substantial proportion of the naturally occurring radioactive materials originally contained in said feed geothermal brine.
A method for treating a feed geothermal brine containing silicon-containing components and naturally occurring radioactive materials comprising:
- introducing said brine into a clarification zone in which silicon-containing components are induced to deposit by addition of a flocculating agent;
- inhibiting the deposition of naturally occurring radioactive materials in said clarification zone by introducing into said clarification zone a phosphono-lower-alkylated amine;
- and
- recovering from said clarification zone a product geothermal brine of substantially reduced content of silicon-containing components but containing a greater percentage of the naturally occurring radioactive materials originally contained in said feed geothermal brine than would be contained in the brine if said phosphono-lower-alkylated amine were not introduced into said clarification zone.
A method for treating a feed geothermal brine containing silicon-containing components, fluoride ions, and one or more metal values comprising:
- introducing said brine into a clarification zone in which silicon-containing components are induced to deposit by addition of a flocculating agent;
- recovering from said clarification zone a product geothermal brine of substantially reduced content of silicon-containing components;
- and recovering metal values originally present in the brine in the presence of a dispersant for inhibiting contamination of said metal values with fluorides present in the brine.
A method for treating a feed geothermal brine containing silicon-containing components, fluoride anions, one or more alkaline earth cations, and one or more metal values comprising silver, said method comprising:
- introducing said brine into a clarification zone in which silicon-containing components are induced to deposit by addition of a flocculating agent;
- recovering from said clarification zone a product geothermal brine of substantially reduced content of silicon-containing components;
- and
- recovering metal values comprising silver from said product geothermal brine in the presence of a fluoride-depositing inhibitor selected from the group consisting polyacrylates, polyphosphonic acids, polyethylene imines, phosphono-lower-alkylated amines, sulfonated polyacrylates, amino-lower-alkyl phosphonates, polyacrylate-acrylamide copolymers, salts of polyacrylate, acrylic acid, polymaleic acid, acrylic acid-maleic acid copolymers, phosphate esters, and phosphonocarboxylate xylate.
Dependencies are inferred from the claim text.