Sulphite Oxygen Controller

Sulphite Oxygen Controller

SULPHITE OXYGEN CONTROLLER is a liquid sodium sulphite product used for oxygen scavenging in low and medium pressure marine boilers.

How does it work?
SULPHITE OXYGEN CONTROLLER reacts rapidly with dissolved oxygen in the boiler to form inert sodium sulphate. this prevents damage caused by oxygen pitting and corrosion in the boiler. Oxygen Scavenger is a convenient to use liquid oxygen scavenger recommended for the complete removal of oxygen from deaerator heaters, feedwater storage areas, feedwater lines, ship condensate return lines, boiler internals and closed recirculating water systems.
The product is dosed to give a reservoir level of sodium sulphite in the boiler. If the reserve drops below a minimum level then oxygen corrosion will occur. It is therefore essential to maintain a level at all times. The product is used as part of a boiler water treatment programme.


Results of use
The interior of the boiler is protected from oxygen corrosion attack. However please note that extra solids are produced in the process so additional blow-down will be required.

Dosing and Sampling
A reserve of 30-50ppm sulphite (Aalborg recommend 30-60 p.p.m) should be maintained in the boiler. SULPHITE OXYGEN CONTROLLER should be dosed continuously to the boiler by means of a metering pump into the feed line after the recirculation line. Continuous dosing can also be achieved by dosing into the hotwell to a point as close to the feed water pump suction as possible, although efficiency is adversely affected by low hotwell temperatures.

A representative sample of boiler water must be obtained, at an interval set by experience in operation of the boiler. The sample should be taken after the regular blow down and analysed immediately. The target usage is 30-50ppm of sulphite. The product should be applied separately to CONDENSATE CONTROLLER and should not be mixed with any alkaline treatment.

18 p.p.m of Oxygen Scavenger are required for each p.p.m of dissolved oxygen, plus a slight excess residual for testing purposes.
Dose per M³ feed = (18 x p.p.m Oxygen) + (________65__________)
Boiler concentration factor

This formula will give 30 p.p.m sulphite as Na²So³
Where Feed temp = 80°C then p.p.m Oxygen = 2.9 p.p.m

Oxygen Scavenger liquid may be fed directly from the shipping container or diluted with clean condensate in a chemical mix tank. It is compatible with most boiler chemical additives except filming amines. Minimum agitation is suggested to prevent premature activation of the oxygen scavenger with oxygen (air) captured by mechanical action at the solution interface. Covered mix tanks or floating plastic plugs are desirable. It may be dosed in conjunction with Liquid Boiler Water Treatment PLEASE TAKE SPECIAL NOTE: DO NOT ADD NEAT LIQUID BOILER WATER TREATMENT AND SULPHITE OXYGEN SCAVENGER TOGETHER. Typically the neat sulphite Oxygen Scavenger should be added to pre-dilute Liquid Boiler Water Treatment in a mixing tank. A typical mix would be for a 100 litres of pre-mixed treatment: 75 litres water, 25 litres Liquid Boiler Water Treatment and 3 litres of Sulphite Oxygen Scavenger.

Oxygen Scavenger is controlled by maintaining a fixed sulphite excess of not less than 30 p.p.m in boilers or 3 p.p.m in feedwater lines, as detectable sulphite using a reagent dropper method or standard titration technique. Aalborg recommendation is 30 -60 p.p.m. Please check specific manufacturer’s instructions as they may vary.

Avoid direct contact with skin and eyes to prevent mild irritation. In case of accidental contact, flush area with water, and seek medical attention. Product should not be ingested. Please refer to Material Safety Data Sheets for detailed handling and storage information.

SULPHITE OXYGEN CONTROLLER is an catalysed sulphite oxygen scavenger used as part of a boiler water treatment programme in low or medium pressure boilers.

Pack Size – 25 litre Drum.
NSN J150-6810-99-378-4863 Product Ref. 0055

Liquid Boiler Water Treatment Extra

Liquid Boiler Water Treatment Extra – generally used as a marine one-shot chemical treatment for Medium-Low Pressure Marine Boilers

pH, corrosion, scale and sludge controller for boiler water

Aquamarine Boiler Water Treatment is a combined concentrate liquid alkaline product that inhibits corrosion, controls alkalinity, controls hardness and oxygen. It is easy to use, non-hazardous and effective. It functions by neutralising acid conditions, precipitating salts, sludge conditioning and oxygen scavenging. For additional Oxygen Scavenger please see separate product details.

Boiler water additive for low/medium pressure boilers (up to 250 psi).

Aquamarine Boiler Water Treatment is fed into the water feed line by means of a continuous feed dosing pump.
Initial dose: 2.4 litres of Boiler Water Treatment/tonne in the boiler water system.


Please download a boiler water log sheet from the log sheet section on the CD or from our website Logs should be submitted monthly for analysis and a report will be sent out by the end of the month in which they are received.
Key parameters are PAlkalinity, Chloride and Sulphite
• Above 200 p.p.m. no dose is required but above 300 PAlkalinity p.p.m. blow down should be implemented
• Sulphite should be kept at 30-50 p.p.m or according to manufacturer’s guide-lines
• Chloride content should be controlled below a level of 200 p.p.m. (Above 200 – Blow-Down) Please ensure that all the test reagents are within the date on the bottle before using.

Feedwater Temperatures – Some typical issues
Temperature of the hotwell is too low. (The temperature should be kept between 70° – 80° C to reduce the oxygen content):
• Return condensate lines and make up line are fitted above the water level. (Tubes to be length under the water level to avoid oxygen intake) Hotwell covers open!
(steam cushion left)
• Temperature of hotwell is above the 90° C. ( Temperature must be kept maximum 90° C to avoid cavitation)
• Feed pump should be placed on the same level as the hotwell or one deck lower to avoid vapour formation in the pump Aquamarine BWT test kit is available for accurate system checking.

(see under Test Kits)

Pack Size 25 Ltr.

NSN J150 6850-99-834-9159 Product Ref. 0003