Method for inhibiting corrosion in aqueous systems

Patent · Wed Nov 15 04:00:00 EST 1978

OSTI ID:5925649

DeMonbrun, J R; Schmitt, C R; Schreyer, J M

A method for inhibiting corrosion in aqueous systems containing components composed of aluminum, copper, iron, or alloys is described. The method consists of incorporating in the aqueous medium 2 to 10 ppM by weight of tolytriazole; an effective amount of a biodegradable organic biocide; 500 to 1000 ppM by weight of sodium metasilicate; 500 to 2000 ppM by weight of sodium nitrite; and 500 to 2000 ppM by weight of sodium tetraborate. All of these concentrations are based on the weight of water in the system and maintain the pH of the resulting system in the range of 7.5 to 8.0. The method permits longterm operation with very low corrosion rates and bacteria counts. All of the additives to the system are biodegradable, permitting the treated aqueous medium to be discharged to the environment without violating current regulations. The method has application to solar systems in which an aqueous medium is circulated through aluminum-alloy heat exchangers.

• Assignee: Dept. of Energy
• Patent Number(s): None
• OSTI ID: 5925649
• Country of Publication: United States
• Language: English

Related Subjects

14 SOLAR ENERGY
141000 -- Solar Collectors & Concentrators
36 MATERIALS SCIENCE
360105* -- Metals & Alloys-- Corrosion & Erosion
ALKALI METAL COMPOUNDS
ALLOYS
ALUMINIUM
ALUMINIUM ALLOYS
AQUEOUS SOLUTIONS
ARYL RADICALS
AZOLES
BIODEGRADATION
CHEMICAL REACTIONS
COPPER
CORROSION PROTECTION
DECOMPOSITION
DISPERSIONS
ELEMENTS
HEAT EXCHANGERS
HETEROCYCLIC COMPOUNDS
IRON
METALS
MIXTURES
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
OXYGEN COMPOUNDS
PESTICIDES
RADICALS
SILICATES
SILICON COMPOUNDS
SODIUM COMPOUNDS
SODIUM SILICATES
SOLAR COLLECTORS
SOLUTIONS
TOLYL RADICALS
TRANSITION ELEMENTS
TRIAZOLES