Method for inhibiting corrosion in aqueous systems

Patent · Tue Dec 02 04:00:00 EST 1980

OSTI ID:6504558

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

This invention is a method for inhibiting corrosion in aqueous systems containing components composed of aluminum, copper, iron, or alloys thereof. The method comprises (A) incorporating in the aqueous medium 2-10 ppm by weight of tolyltriazole; an effective amount of a biodegradable organic biocide; 500-1000 ppm by weight of sodium metasilicate; 500-2000 ppm by weight of sodium nitrite; and 500-2000 ppm by weight of sodium tetraborate, all of these concentrations being based on the weight of water in the system; and (B) maintaining 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 special application to solar systems in which an aqueous medium is circulated through aluminum-alloy heat exchangers.

• Assignee: Department of Energy
• Patent Number(s): US 4237090
• OSTI ID: 6504558
• Country of Publication: United States
• Language: English

Related Subjects

14 SOLAR ENERGY
141000 -- Solar Collectors & Concentrators
36 MATERIALS SCIENCE
360105* -- Metals & Alloys-- Corrosion & Erosion
ALLOYS
ALUMINIUM ALLOYS
AQUEOUS SOLUTIONS
BIODEGRADATION
CHEMICAL REACTIONS
CORROSION INHIBITORS
CORROSION PROTECTION
DECOMPOSITION
DISPERSIONS
EQUIPMENT
FLUIDS
HEAT EXCHANGERS
HEAT TRANSFER FLUIDS
MIXTURES
SOLAR COLLECTORS
SOLAR EQUIPMENT
SOLUTIONS