Catalyzed Hydrazine Hydrate - For Boiler Maintenance

Boilers are used for heating water at more than its initial temperature for adequate steam generation. Water is used as a heating agent in boilers, as it is abundant, inexpensive and easily available. Due to the many dissolved salts present, some residue contaminants affect the quality of steam. This may cause many deficiencies in system including scaling, foaming, priming and corrosion. For ceaseless execution of process, these deficiencies should be treated with time, this strategy prevents any disruptions and detrimental effects in the boiler system. Dissolved gases such as oxygen and carbon dioxide will react with the metals in the boiler system and lead to boiler corrosion. In order to protect the boiler from these malfunctions, some specific conditioning agents are used in subsequent treatment processes.

Catalyzed Hydrazine Hydrate is a hydrated solution of hydrazine. It is especially used in boilers, where it works as Oxygen Scavenger and removes the excess oxygen in feed water.

Oxygen in water causes pitting, that is very acute because of its localized nature. Water containing ammonia, particularly in the presence of oxygen, readily attacks copper and copper bearing alloys. The resulting corrosion leads to deposits on boiler heat transfer surfaces and reduces efficiency and reliability. Oxygen is highly corrosive to most of the metals, especially the mild steel used for boiler tubes. Iron oxide generated by the corrosion can cause iron deposits in the boiler, and also shortens its lifespan.

Catalyzed Hydrazine Hydrate is used after mechanical deaeration of water and results complete corrosion inhibition by Oxygen in boilers. Catalyzed Hydrazine Hydrate is a colourless liquid which is highly soluble in water. It is a powerful reducing agent that reduces oxygen to form nitrogen and water.

N2H4 + O2 → 2 H2O + N2

At high temperatures and pressures, the reaction between hydrazine and dissolved oxygen also forms very small quantities of ammonia.

It is observed that mere 0.1 ppm hydrazine (0.01% hydrazine) lowers the DO level tremendously, as hydrazine reacts with molecular oxygen. On decreasing the hydrazine addition, say 0.3mL, to the 30L de-aerated water, at 30°C, it results 54% oxygen scavenging and, comparably observance of 98% scavenging with 3mL hydrazine suggested that oxygen scavenging is concentration dependent as lower the hydrazine content, lower is the oxygen scavenging. Similar concentration dependence of scavenging action had been also been observed at 45, 60, 75°C too.

Catalyzed HH is generally used in boilers with pressures of 40 bar and over, but they can also be used for lower pressure boilers suffering from oxygen corrosion. Catalyzed HH does not donate solids to the system, and reduces the quantity of derivating sludge particles after the process. It also forms protective magnetite film by reacting with soft Haematite Layers (Red Iron Dusts) on the boiler tubes and drums, which helps in inhibiting further corrosion.

Acuro Organics Limited offers Catalyzed HH, being successfully used in boilers for oxygen scavenging.  

 Catalyzed HH