A method for dealing with outliers of flue gas NOx concentration based on standard deviation and median of absolute deviation

Abstract

The invention relates to a flue gas NOX concentration abnormal value processing method based on a standard deviation and absolute deviation median. The method comprises the steps of: 1, collecting a measured value sequence of the NOX concentration of flue gas on the A side and a measured value sequence of the NOX concentration of flue gas on the B side of an n-dimensional historical SCR denitration system, and calculating the difference value of the sum at each moment, wherein n is determined by historical normal data volume and actual data requirements; 2, calculating the mean value and the standard deviation of the difference values of the n A side flue gas NOX concentrations and B side glue gas NOX concentrations. The beneficial effects of the invention are that: the invention providesa new processing method for solving the problem that NOX measured values at the inlet and the outlet of an SCR system are abnormal; the abnormal values are processed by utilizing an NOX measured valuesequence of multiple measuring points through a filtering method based on the standard deviation and absolute deviation median, so that the reliable and applicable NOX concentration of flue gas is obtained. According to the method, the problem of abnormal measurement of the NOX concentration of flue gas can be solved by utilizing a relatively simple statistical method, and the method can be further popularized to other abnormal measurement problems.

Description

technical field [0001] The present invention relates to a method for monitoring process parameters of a denitrification system in a coal-fired power plant, in particular to a method for monitoring flue gas NO based on standard deviation and absolute deviation median X Concentration outlier processing method. Background technique [0002] Nitrogen oxides are an important part of air pollutants. How to deal with nitrogen oxides in the exhaust gas produced by coal-fired power plant boiler combustion is a hot topic at present, and how to achieve a balance between energy saving and environmental protection has become a current technical difficulty . According to the data of nitrogen oxides at the denitrification outlet, the flow rate of ammonia supply can be adjusted to ensure that the reactant is fully and reasonably used, and the cost can be effectively saved. Due to a series of problems in the measurement points and data collection process, there are bound to be errors in th...

AI Technical Summary

Problems solved by technology

Most of the existing methods use a series of physical methods to reduce measurement bias through specific analysis of specific scenarios, but lack data-driven methods with generalization capabilities for outlier processing

In addition, currently commonly used methods such as moving median filtering and standard deviation filtering tend to filter normal mutation values ​​as outliers during filtering, and cannot obtain reliable filtering effects

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