CORROSION INHIBITOR FOR RECIRCULATING COOLING WATER

DESCRIPTION:

ALKEN® NPC-767 is an exceptionally effective corrosion inhibitor for use in open recirculated cooling water systems. ALKEN® NPC-767 contains a special blend of cathodic corrosion inhibitors, including zinc, designed to inhibit corrosion of ferrous metals by creating a passivating barrier. A specific inhibitor is included also to protect copper alloys from corrosion. ALKEN® NPC-767 is recommended for use when the system water is soft and low in alkalinity. It is not applicable when the water is scale-forming.

ADVANTAGES:

• STABLE even at elevated skin temperatures.
• EFFECTIVE corrosion control at stability indices as high as 10.5.
• ANTIFOULANT properties maximize heat transfer, minimize under-deposit corrosion.
• PROTECTS against galvanic corrosion in mixed-metal systems.
• EXCEPTIONALLY EFFECTIVE control of pitting of ferrous metals.
• CONVENIENT single-package treatment for corrosion and fouling.

DOSAGES:

ALKEN® NPC-767 dosages may vary somewhat according to operating conditions, but generally 100-125 ppm of NPC treatment should be maintained in the system water. (This is equivalent to about 1 pint of NPC per 1000 gallons of water.) This dosage should be tripled for a two-week period when initiating treatment, whenever the system is refilled with fresh water, and after any major system upsets, in order to establish effective corrosion control. If the stability index of the recirculated water is higher than 10.5, an alkalinity booster such ALKEN® TREATMENT 479 should be fed to reduce the index to less than 10.5. ALKEN® NPC-767 should not be used when the stability index of the system water is below 7.0.

FEEDING:

ALKEN® NPC-767 must be fed continuously to the system by a proportioning pump. Automated systems to control conductivity, pH, and inhibitor level in the system water are available from ALKEN-MURRAY, which may include micro-processor control and interfacing with other computers in the plant.

PACKAGING & HANDLING:

ALKEN® NPC-767 is shipped in containers conforming to Performance Oriented Packaging standards. Consult the current Material Safety Data Sheet for precautions in handling and storing this product.

ENVIRONMENTAL NOTE:

In some areas, the release of zinc into receiving waters or sewers may be restricted. Before recommending ALKEN® NPC-767, ensure that the presence of 2-3 mg/L of zinc in the tower blowdown will not put your customer in jeopardy of violating any restrictions. In particular, the customer's discharge permit, if any, should be checked for any limitation on zinc discharges.

Update: 02-25-2007