Method and system for denitration control of thermal power plant

Abstract

The invention discloses a method and a system for denitration control of a thermal power plant. The method comprises the following steps: calculating an O'clock every hour average value of NOX emission amount according to an NOX emission concentration value detected at a chimney by a CEMS (Continuous Emission Monitoring System); then judging whether the O'clock every hour average value is within apreset NOX emission threshold value range or not, increasing the ammonia spraying amount if the O'clock every hour average value is higher than a preset NOX emission threshold value, and reducing theammonia spraying amount if the O'clock every hour average value is smaller than the preset NOX emission threshold value. Compared with a traditional method for controlling the ammonia spraying amountaccording to an emitted NOX real-time concentration value, environment protection assessment standard can be met by just ensuring that the O'clock every hour average value accords with the preset NOXemission threshold value no matter how big an emitted NOX real-time concentration value is, the ammonia spraying amount can be accurately controlled on the premise that the NOX emission amount according with the environment protection requirements is ensured, and the situation that too much or too less ammonia is sprayed can be prevented from happening, so that the probability of blocking an airpre-heater is reduced, the resistance of a draught fan is reduced, and the overhauling cost is reduced.

Description

technical field [0001] The invention relates to the technical field of exhaust gas treatment, in particular to a denitrification control method and system for thermal power plants. Background technique [0002] Thermal power generation is still a relatively important power generation method at present, but with the requirements for environmental protection, how to reduce pollutant emissions while ensuring the normal operation of thermal power generation equipment is the main development requirement for thermal power generation. [0003] The existing denitrification control method is mainly to detect NO at the outlet of the reactor. X (nitrogen oxides), however, the environmental assessment standard is the NO measured by the CEMS (Continuous Emission Monitoring System) of the environmental protection department at the chimney. X As the standard, the length of the flue between the two measuring points is far away, and there are many important equipment in the middle, such as ...

AI Technical Summary

Problems solved by technology

[0008] The purpose of the present invention is to provide a denitrification control method and system for thermal power plants, which can effectively solve the problems of inaccurate control of the amount of ammonia injection

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