Boiler Water Treatment Chemicals

Boiler Water treatment is necessary due to problems occurred in boiler like scaling, carryover, corrosion & Pitting in Internal Tubes & Condensate lines. Boiler water should be free from all type of Hardness, Dissolved Oxygen which always implies scaling resulting in poor heat transfer& higher fuel consumption. Boiler Water treatment programme consist of combination of Oxygen Scavenger, Alkalinity Builder, Scale Inhibitor, All Volatile Treatment Programme ,Amine Treatment & Inorganic Phosphate & Polymers.

Objectives of Boiler Water Treatment Programme:

It consists of External & Internal Treatment Programme .External Treatment is the removal of impurities from incoming water which was used in boiler. This is use when different type of feed water quality is to be use in boiler system. There are so many ways as Deaeration, Evaportion, Softening .Membranes for the treatment of feed water for a particular system. Internal Treatmentis the treatment of impurities within the boiler system. The reactions occur properly in feed tank & boiler drum. Internal treatment is use alone or with external treatment. Main purpose is to properly reaction of Scale Conditioner, Oxygen Scavenger & Alkalinity Builder with feed water impurities & here chemicals addition is made to feed water Boiler Water & Steam.

The commonly used products include:

• Phosphates & Polyphosphates Dispersants : Itreacts with alkalinity of boiler water & neutralize the hardness of water by forming complex phosphate forms & also some insoluble compound that can be easily remove by blow down .

Anti-Scaling agents: increase the dispersive properties of the conditioning products. They can be Lingo sulphonates, tannins, Polyacrilates, malefic styrene copolymer etc.

• Oxygen scavengers: They are divided in two categories Volatile & Non Volatile .Volatile are as Hydrazine, Diethyl hydroxylamine Amine (DEHA),Carbohydrazide, MEK Base while Non Volatile are as Sodium Sulphie & Tannin Base. These scavengers reduce the oxides and dissolved oxygen & passivate inner metallurgy & metal surfaces.
• Anti-foaming or anti-priming agents: Mixtures of surface-active agents remove foam and prevent the carryover of fine water particles in the steam.
• All Volatile Treatment: In this volatile Conditioning chemicals are used with D.M. Water in order to maintain Virtual Absence of Solids in Boiler Water.