What is the purpose of phosphate in boiler water?

What is the purpose of phosphate in boiler water?

Phosphate buffers the boiler water, reducing the chance of large pH swings due to the development of caustic concentrations. In phosphate treatment, excess caustic combines with disodium phosphate to form trisodium phosphate.

Why is phosphate conditioning better than carbonate conditioning?

Phosphate conditioning is more beneficial than carbonate conditioning. Monosodium and disodium phosphate can be used for alkaline and neutral water. Carbonate conditioning is used in low pressure boilers. In this method, sodium carbonate solution is added to convert the calcium ions to soft and loose sludge.

What is Calgon conditioning How is it better than phosphate conditioning?

In calgon Conditioning, the added calgon forms soluble complex compound with CaSo4, thereby it prevents the scale and sludge formation in water. this soluble complex does not cause any problem in boilers. 2Na₃PO4 + 3 CaSO4 —> Ca₃(PO4)₂↓ + 3 Na2 SO4. Hence calgon conditioning is better than phosphate conditioning.

How does phosphate conditioning prevent scale formation?

(iv) Calgon conditioning involves in adding calgon [sodium hexameta phosphate (NaPO3)6 to boiler water. It prevents the scale and sludge formation by forming soluble complex compound with CaSO4.

What is phosphate conditioning?

This process is used in internal conditioning of boiler water, on the one hand and conditioning of cooling and process water, on the other orthophosphate such as trisodium phosphate and complex phosphates scuh as sodium hexametaphosphate are both used in steam boilers to precipitate whatever small amounts of calcium …

Why ammonia and hydrazine is added in boiler feed water?

2.2 Corrosion-control effects of hydrazine Oxygen dissolved in water causes corrosion. Because hydrazine removes this oxygen via the reaction N2H4 + O2 → N2 + 2H2O, it is useful in preventing corrosion. It decomposes at a temperature of 200°C or more to form ammonia (3N2H4 → 4NH3 + N2) , which acts as a pH adjuster.

What is meant by calgon conditioning?

Calgon conditioning: It is the process of addition of calgon or sodium hexametaphosphate to boiler feed water. The calcium ions (responsible for scale / sludge formation) are complexed by calgon to form a soluble complex and hence prevented from their scale forming action.

What is calgon conditioning?

What is Calgon treatment of boiler feed water?

Reagent added is Calgon. Calgon = sodium hexa meta phosphate The process involves the addition of calgon to boiler water. It prevents scale and sludge formation by forming highly soluble calcium hexa meta phosphate complex compound with CaSO4. 4) Describe the demineralization process of softening of hard water.

Why Hard water is unfit for boiler?

Hard water that’s filled with minerals like calcium and magnesium can cause damage to the tubes inside water boilers. This is because the dissolved ions are left behind when the water is heated to steam. The remaining ions bond to form calcium carbonate, aka limescale.

How do you remove hydrazine from water?

On the basis of the obtained experimental data, it is shown that the most suitable and environmentally safe method of detoxifying of hydrazine in waste waters is through oxidation of it by hydrogen peroxide in the presence of Cu(II) ions together with the bubbling of air.

How do I stop foaming and priming?

The most common measure to prevent foaming and priming is to maintain the concentration of solids in the boiler water at reasonably low levels. Avoiding high water levels, excessive boiler loads, and sudden load changes also helps.

How are phosphates used in boiler water treatment?

In systems where the feed water is less than 1° TH, phosphates are used to regulate alkalinity or boiler water pH and, therefore, to avoid acid or alkaline corrosion of boiler internal walls. Phosphates are often combined with natural and/or synthetic dispersants;

What kind of chemicals are used in boiler water treatment?

The softening chemicals used include soda ash, caustic and various types of sodium phosphates. These chemicals react with calcium and magnesium compounds in the feed water. Sodium silicate is used to react selectively with magnesium hardness.

What kind of supplements are used for boiler deposits?

Analyses of typical boiler deposits show that magnesium silicate is present in roughly the same ratio to calcium phosphate as magnesium is to calcium in boiler feedwater. Phosphate treatment results are improved by organic supplements. Naturally occurring organics such as lignins, tannins, and starches were the first supplements used.

What happens to calcium sulphate in boiler water?

High temperatures in the boiler water reduce the solubility of calcium sulphate and tend to make it precipitate out directly on the boiler metal as scale. Consequently calcium sulphate must be reacted upon chemically to cause a precipitate to form in the water where it can be conditioned and removed by blow-down.