Boiler combustion optimizing control system and optimizing control method based on accurate measurement system

Abstract

The invention discloses a boiler combustion optimizing control system and a boiler combustion optimizing control method. The method comprises the following steps of: on the basis of the equilibrium distribution and transformation for coal powder in a fire coal unit, accurately measuring parameters such as wind, powder, ash and the like by using a measuring device; analyzing a history behaviour of operation by the deep analysis and digging of data by using the acquired real-time history data of a boiler and taking the work condition optimization as a basic optimizing method; establishing mathematical models among operation parameter, status input parameter and parameters such as boiler efficiency, NOx and the like in the combustion process to obtain a unit operation mode knowledge base; performing the whole plant energy-saving and emission-reducing comprehensive assessment and diagnosis; analyzing the unit operation potential; and providing a knowledge base and a rule for optimizing operation; optimizing boiler combustion parameter configuration aiming at different combustion indexes or an index combination to realize the optimization of multiple optimizing objects and propose an energy-saving and emission-reducing implementation scheme and measurement in a classification mode. The method not only can realize closed-loop optimizing control but also can realize on-line optimizing guide.

Description

Technical field [0001] The invention belongs to the technical field of boiler optimized combustion, and specifically relates to an optimized control system and an optimized control method based on accurate measurement of boiler combustion parameters, historical optimization and closed-loop control, and is suitable for coal-fired generating sets. Background technique [0002] Currently, coal-fired power plants are facing the dual pressure of energy saving and reduction of NOx emissions. It is recognized that reducing NOx emissions while reducing coal consumption through combustion adjustment is the best solution. However, the current control of the combustion process still stays on the very backward total parameter control method, such as the boiler outlet oxygen and steam parameters, etc. This control method leaves great potential for the optimization and adjustment of boiler combustion. [0003] Boiler combustion optimization control is an important technical way to realize energ...

AI Technical Summary

Problems solved by technology

If the pulverized coal in the stratified state enters the burner, there will be a large deviation in the mass flow rate of the pulverized coal between the burners, up to more than 30%, and a series of problems such as flame instability and uneven combustion will occur.

[0007] 2. Unable to measure and adjust the air-powder two-phase flow online

However, in the past, due to the inability to measure and adjust the air-powder two-phase flow online, the coal feeder speed was used to replace the amount of coal to each burner, and then the air volume required by the corresponding coal feeder was determined.

This method does not consider the different characteristics and nonlinearity of the coal mill, separator and pulverized coal pipe, which leads to a large difference in the amount of pulverized coal to each burner at the same coal feeder speed, so that the coal volume and air volume cannot be matched correctly

[0009] 3. Lack of accurate and sufficient means of measurement

[0010] Domestic power plants have the problems of low installation rate, poor accuracy and stability of online detection of carbon content in fly ash, wind and powder, and lack of accurate measurement methods for parameters such as wind, powder and ash that reflect the combustion state of the boiler, which directly affect the optimization of combustion. Accuracy of modeling and optimization results

[0011] 4. The combination of closed-loop control and optimal operation adjustment is not enough

Considering the difficulty of online calculation and the lack of correlation analysis between the direct measurement value and the optimization target, the combustion optimization method of artificial intelligence is also difficult to realize

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