Method for improving denitration rate of SCR (Selective Catalytic Reduction) denitration system of power station boiler

Abstract

The invention discloses a method for improving the denitration rate of an SCR (Selective Catalytic Reduction) denitration system of a power station boiler. The method comprises the following steps: (1) measuring concentration distribution of NOx at the outlet of an SCR denitration reactor; (2) calculating the unevenness Cv of concentration distribution of NOx according to the measuring result in the step (1); (3) when Cv is greater than 20%, adjusting the valve opening in an area corresponding to an ammonia injection grid according to the concentration distribution of NOx at the outlet of the SCR denitration reactor; (4) repeating the steps (1) to (3) until Cv is less than or equal to 20%. Through optimization and adjustment by the invention, the evenness of distribution of NOx at the outlet of the SCR denitration reactor is remarkably improved, and the relative standard deviation of NOx is reduced from 46.4% to 14.8%. On the premise of ensuring that ammonia escape does not exceed standard, the denitration rate is improved from 77% to 83%. The method disclosed by the invention has important guiding meaning and engineering application value to safe, efficient and stable operation of the SCR denitration system of the power station boiler.

Description

technical field [0001] The invention relates to an SCR denitrification system of a coal-fired power station, in particular to a method for improving the denitrification rate of the SCR denitrification system of a power station boiler. Background technique [0002] my country is a country where coal is the main primary energy source. Coal accounts for more than 60% of total energy consumption, and coal consumption for power generation accounts for 50% of coal consumption, and this trend will continue for a long time. In 2005, the national nitrogen oxide emission was 19.1×106t, and the NO in my country’s atmospheric environment x The concentration is much higher than other countries and regions, among which the contribution rate of power plants is 43%. It can be seen that coal-fired power generation is one of the main sources of air pollutant nitrogen oxides in my country. Since the "Twelfth Five-Year Plan", the Chinese government has attached great importance to the control...

AI Technical Summary

Problems solved by technology

This will affect the overall denitrification effect of the system and bring great harm to the economic and stable operation of the system

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