Hydrazine Analysis in Power Plant:
The main objective of adding hydrazine in the boiler feedwater is to prevent dissolved oxygen corrosion effects.
Hydrazine holds a double function in the boiler water chemistry.
It first eliminates the dissolved oxygen (since hydrazine is an oxygen scavenger). The product of reaction between hydrazine and oxygen is nitrogen (N2H4 + O2 --> N2 + 2H2O) which has no bad effect on the boiler and turbine operation.
The residual hydrazine, once heated in the boiler decomposes to ammonia (3N2H4 --> N2 + 4NH3) which is a chemical used in the boiler water treatment.
Hydrazine (one of the costlier chemical) monitoring enables the power plant chemist to avoid under or overdosing hydrazine.
Normal working range: 0 to 20 ppb or 0 to 200 ppb
Hydrazine analyzer is provided with set point arrangement facility which can be use to control hydrazine dosing & thereby reduces cost of consumption of hydrazine in plant.