SNCR denitration automatic control method and system thereof

The invention discloses an SNCR denitration automatic control method and a system thereof. The method comprises the steps 1-5. The system comprises a control module, an ammonia water pump, a nitrogenoxide collection module and a PID function module, wherein the control module is internally provided with a timing module and a data processing module; full-automatic control of an SNCR system can beachieved; on the premise that nitric oxide is controlled to meet the environmental protection requirement, nitric oxide control does not exceed the standard and is not too low; an ammonia water control mode and a nitrogen oxide control mode can be automatically switched without disturbance; the ammonia water spraying amount is calculated according to the nitrogen oxide content and the formula thatthe ammonia water flow set value = the ammonia water flow set value at the last moment +/- the ammonia water step length, and the automatic tracking control of the nitrogen oxide is controlled by automatically adjusting the am