Boiler water method and ammonia-diazine method for protection

Thread Content

This method is used when the boiler is out of service for an extended period. After the boiler is taken out of service, drain all the water from it, remove or isolate the copper components in the system, and fill it with an ammonia solution prepared from condensate or feedwater at a concentration of 700–800 mg/L ； Or, after the boiler is taken out of service, water is not drained, and ammonia and hydrazine are directly introduced. Maintain the pH level of the water in the boiler between 10 and 10.5, with an excess amount of hydrazine of 200 mg/L. The liquid medicine is pumped into the system and circulated to ensure uniform distribution; once the boiler is fully filled with the protective liquid, all valves are closed. During the shutdown period, the entire system must be airtight to prevent air from entering. Using this method, when the boiler is to be put back into operation, all the protective fluid must be drained completely and the boiler must be thoroughly flushed. After ignition, steam should first be vented through the exhaust valve to the atmosphere, and steam can only be supplied once the ammonia content in the steam is below 2 mg/kg, in order to prevent high ammonia concentrations from corroding the copper tubes of the condenser.