Question: Why Hydrazine Is Dosed In Boiler?

What is the purpose of hydrazine?

Hydrazine is a convenient reductant because the by-products are typically nitrogen gas and water.

Thus, it is used as an antioxidant, an oxygen scavenger, and a corrosion inhibitor in water boilers and heating systems..

What chemicals are used in boiler water?

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.

How do you kill hydrazine?

Hydrazine is not hydrolyzed but easily oxidized by dissolved oxygen in the aquatic environment and degraded. Hydrazine at a low concentration can be eliminated by biodegradation.

How do you get hydrazine?

Currently, most hydrazine is produced by the ketazine process, which is a variation of the Raschig process. Ammonia is oxidized by chlorine or chloramine in the presence of an aliphatic ketone, usually acetone. The resulting ketazine is then hydrolyzed to hydrazine.

What should the pH of boiler water be?

pH 11Boiler water should be maintained at pH 11. Generally, the higher the pH (basic), the less soluble some solids are in the water. The lower the pH (acidic), the more soluble these solids are.

Why do we test boiler water?

Industrial Boiler water testing is important to understand the scaling or corrosion potential of the water, to see whether sufficient chemical inhibitor is present and whether there is risk of carryover which can contaminate product if you use live steam or cause corrosion of steam and condensate lines with wet steam.

Why is hydrazine explosive?

Hydrazine is also used as rocket fuel propellant. Mixing it with oxidising agent dinitrogen tetroxide, N2O4, creates a hypergolic mixture – a mixture so explosive, no ignition is required. … This, along with fuel leaks, killed more pilots than enemy fire.

Why is phosphate used in boilers?

Phosphate compounds are common additives for boiler water treatment. Phosphate compounds react with any remaining hard water compounds to create a soft sludge that is eliminated through blowdown. … Phosphates also scavenge (or remove) any remaining oxygen and create a pH buffer to minimize corrosion potential.

Why does silica increase in boiler drum?

Silica build-up is monitored inside the boiler drum. The silica concentration is distributed between the water and vapour phases in a boiler. As the temperature and pressure are increased, more silica becomes present in the steam. … This is the removal of contaminated water from the boiler.

Why ammonia is dosed in boiler?

Ammonia is commonly used cheaper material to maintain pH in boiler water. … In OT Ammonia is used to control pH and remove little Oxygen, but slightly oxidizing environment is maintained to promote formation of oxidizing layer on the metal surface.

What is boiler water conductivity?

For boiler water, the conductivity increases at the rate of approximately 2% (of the value at 25°C) for every 1°C increase in temperature. This can be written as: Example 3.12.3. A boiler water sample has an unneutralised conductivity of 5 000 μS/cm at 25°C.

What is CBD in boiler?

Continuous blowdown (CBD) refers to the removal of the dissolved solids portion of these impurities. … This tube is connected by external piping to a blow-off tank, or pond, so that boiler water with a high level of total dissolved solids (TDS) can be removed.

What is LP and HP dosing?

Dosing System basics…  In a typical boiler feed water dosing system:  The HP Dosing system doses direct into boiler drum, under high pressure.  The LP Dosing system doses into the boiler feed water pump suction line, or, de-aerator inlet line, under low pressure PSI ENGG SYSTEMS P. LTD.

What does phosphate do in boiler water?

Phosphates. Phosphate treatment programs precipitate calcium and magnesium hardness from boiler feedwater in the form of hydroxyapatite and serpentine. These compounds form sludge, which, when properly conditioned with polymers, is removed from the boiler via blowdown.

Is hydrazine acidic or basic?

Chemical properties: Hydrazine is a highly reactive base and reducing agent, and is widely used in organic synthesis. Hydrazine is a moderate base, while its aqueous solutions are highly alkaline. It reacts violently with oxidants, acids, metals and metal oxides, creating a potential fire and explosion hazard.

Why hydrazine is used in boiler water treatment?

Hydrazine hydrate is mainly used as a raw material for plastic foaming agents, with 28% of hydrazine used in water treatment and pH control. Oxygen dissolved in water causes corrosion. Because hydrazine removes this oxygen via the reaction N2H4 + O2 → N2 + 2H2O, it is useful in preventing corrosion.

Why ammonia and hydrazine is added in boiler feed water?

surfaces which acts as an additional protection against oxygen corrosion. C The excess hydrazine in the boiler breaks down to produce ammonia which has beneficial effects in raising the pH of the steam/condensate system and thus affords some protection to the system by neutralising any carbon dioxide.

How dangerous is hydrazine?

Symptoms of acute (short-term) exposure to high levels of hydrazine may include irritation of the eyes, nose, and throat, dizziness, headache, nausea, pulmonary edema, seizures, and coma in humans. Acute exposure can also damage the liver, kidneys, and central nervous system in humans.

How do I control the pH of my boiler water?

Controlling pH pH is controlled by either removing water impurities or adding other chemicals to neutralize the condition. For example, Caustic Soda, an alkaline, is added to neutralize CO3, carbonic acid.

Why is hydrazine so toxic?

Liquid hydrazine on the skin is quickly absorbed and acts as a neurotoxin. Burning hydrazine is extremely hot, but produces no visible flame (yes, it’s like invisible fire!) which can quickly spread to other combustible materials (clothes, skin, etc.).

What is hydrazine made of?

Hydrazine is a chemical compound that acts like water and is made of nitrogen and hydrogen atoms. It is basic and has chemical properties similar to those of ammonia. Hydrazine, N2H4, is a chemical compound that is made by coupling a pair of ammonia with one hydrogen removed from each.