ADJUNCT Hardness Controller

Hardness Control is formulated to form a precipitate with calcium ions which will not adhere to metal surfaces but are in a form suitable for blowdown. Disodium phosphate as a scale controller used in lowpressure boiler systems (0-32 bar) and medium-pressure steam propulsion vessels (32-60 bar) also in boiler water treatment program for highpressure steam generating systems (60-84 bar).

Used for boilers and water softening.

Formation of Calcium Sulfate is main cause for SCALE formation :::

The principal problem potential posed by sulfate ions in water is the possibility of calcium sulfate scale formation.  Precipitation of calcium sulfate can occur when high concentrations of both calcium and sulfate exist simultaneously.  There are three primary areas of water treatment in which calcium sulfate precipitation may occur boilers, cooling systems, and ion exchangers operating in the hydrogen or acid mode.

In boilers, calcium sulfate scale formation has been reduced to a minimum by modern treatment practices.  The low hardness levels largely preclude calcium sulfate boiler scale.    By contrast, cooling systems are subject to calcium sulfate scale deposition because the makeup is usually not treated for hardness removal.  Cooling water is usually treated with sulfuric acid for pH control, and the makeup is cycled, i.e. concentrated.  Calcium sulfate scale deposition can  result unless the cycles of concentration are properly controlled in conjunction with the proper use of scale control chemicals.  Cation ion exchangers regenerated with sulfuric acid also can pose a major calcium sulfate problem. Calcium sulfate precipitation can be avoided by controlling the acid concentration and the flow rate through the exchanger.  

Sulfate content can be calculated in Laboratory by using this method ::: http://rxmarine.com/SULFATE-TEST-KIT

For optimum results dose Hardness Control direct to the boiler via the bypass pot-feeder. The dry powder should be dissolved in hot water (50°C) at a ratio of 1 part powder to twenty parts condensate (e.g. 500 grams/10 litres). Ensure that treatment is fully dissolved before dosing.


This  treatment dosed at 1.49 grams per ton of distilled water provides 1.0 ppm phosphate.

Feed Points: Dose with other BOILER CHEMICAL/alkaline liquid by diluting withcondensate and feed directly into the system drum (below the water level) using a bypass pot feeder. For low-pressure boilers, It may be dosed to the hotwell or condensate return tank, although this is not the preferred method.
 

Dosage and control

Select row on righthand side for applicable pressure range. Compare test result with comment in table and dose stated amount of product per ton boiler water volume.

These are recommended values based on experience and are in no way intended to replace the boiler manufacturer's specifications or company regulations.

The use of Disodium phosphate treatment in BOILER converts calcium hardness into soft, non-adherent sludge that is easily removed by blowdown.
Sampling And Testing

A sample of boiler water should be drawn for analysis daily. The sample should always be taken from the same point after blow down, cooled and tested immediately. Follow the Rxsol Hardness Test Kit instructions and fill the Boiler Water Log Form according to result results. It is important that regular testing is carried out to ensure levels of treatment are correct.

Physical Properties :

Appearance        :White powder
Corrosive action  :NonE
pH 1% solution   :8.8
Flash point         :None