Product information

This product supersedes product no: 777705

Features

  • NALFLEET™ Oxygen Control is a liquid product, easy to feed
  • Does not contribute to conductivity
  • Protects boiler, steam lines, condensate lines and feed water lines from corrosion
  • Fast action due to catalyst
  • Assists mechanical deaeration
  • Simple test to determine level of treatment
  • NALFLEET™ Oxygen control can be used to condition the water used for laying up the boiler in a wet condition.

Benefits

  • Economical in use
  • Reduces corrosion of iron and copper, increasing system life and reliability
  • Passivates metal in the boiler

Specification

Safety Data Sheet (SDS)

Documents

Directions for use

NALFLEET™ Oxygen Control can be used in all boiler systems, from low to high pressures and in conjunction with mechanical de-aeration systems. The treatment combines with dissolved oxygen to form water and inert nitrogen gas, thus effectively removing O2 from the water. No solid materials are produced, so there is no contribution to the increase in total dissolved solids -a critical factor in high pressure boilers. The removal of dissolved oxygen is vital for preventing oxygen pitting and corrosion in boilers. NALFLEET™ Oxygen Control reacts with ferrous and non-ferrous oxides to prevent general corrosion.Ferric oxide (red rust, Fe2O3) is converted to magnetite (black iron oxide, Fe3O4), which is a tough corrosion resistant oxide which protects the metal surface. The term for this is 'passivating' the surfaces, so that they are protected from further corrosion.

Dosing method

For optimum protection, NALFLEET™ Oxygen Control should be fed continuously into the boiler feed line, after the feed pump recirculating valve, using an automatic dosing systems. For steam turbine systems, NALFLEET™ Oxygen Control can be dosed into the cross over between the H.P. and L.P. turbines or the storage section of the deaerator for full protection.

Dosage and control

The objective is to maintain a hydrazine residual between 0.05-1.0 ppm depending on operating pressure and boiler design. Actual consumption is determined under operating conditions.

HYDRAZINE TEST RESULT ppm

Boiler Pressure

Control Range

0-0.05ppm

0.05-0.10

0.10-0-.50

0.50-1.00

1.00-1.50

<18 to 31 bar

0.1-1.0ppm

Increase dose 25%

Increase dose 25%

Satisfactory Maintain dose

Satisfactory Maintain dose

Decrease dose 25%

31 to 42 bar

0.1-0.5ppm

Increase dose 25%

Increase dose 25%

Satisfactory Maintain dose

Decrease dose 25%

Decrease dose 25%

Recommended Control Limits in ppm. These are typical values. Follow boiler manufacturers guidelines where required.

Wet lay-up

When wet lay-up of the boiler is required then a minimum dosage of 1.25 litres/tonne of boiler water is required.

Sampling and testing

A representative sample of boiler water should be drawn for analysis daily. The sample should always be taken from the same point after blowdown, cooled and tested immediately. Follow the WSS Test Kit instructions and log the results in Waterproof. The results should be sent to WSS as stated in the Waterproof instructions.
It is important that regular testing is carried out to ensure levels of treatment are correct.