Coal-fired power plant boiler intelligent soot blowing closed-loop control method, device and system

Abstract

The invention discloses an intelligent soot blowing closed-loop control method, device and system for a coal-fired power station boiler. The method includes the steps that a cleaning factor, a time integral factor and a corresponding supplement factor of a heating surface are determined according to field data collected in real time and are converted into quantization levels respectively in the fuzzy field; the cleaning factor quantization level, the time integral factor quantization level and the supplement factor quantization level are input into a preset soot blowing fuzzy control model, and the soot blowing fuzzy control model is resolved to obtain a corresponding soot blowing confidence coefficient; a corresponding soot blowing instruction is generated according to the soot blowing confidence coefficient and working conditions of a unit and is then sent to a PLC so that the PLC can carry out corresponding soot blowing operation according to the soot blowing instruction. Closed-loop control over a soot blowing system is achieved by comprehensively considering operation factors affecting soot blowing, soot blowing frequency is reduced to the minimum under the condition that heat transfer characteristics of the heating surface are guaranteed, and the purposes of saving energy, reducing consumption and improving the operation economy and safety of the unit are achieved.

Description

technical field [0001] The invention relates to the fields of energy-saving transformation and information control of pulverized coal boilers, in particular to an intelligent soot-blowing closed-loop control method, device and system for coal-fired power plant boilers. Background technique [0002] Thermal power installed capacity has been widely used due to its large capacity and high energy consumption. However, slagging and ash accumulation on the heating surface of utility boilers is an important problem affecting the safe and economical operation of pulverized coal boilers. Due to the accumulation of dust, the heat transfer resistance of the heating surface increases and the heat exchange deteriorates, which reduces the heat transfer efficiency. Generally speaking, compared with the clean state, the efficiency of the boiler will be reduced by 1%-2.5% after being polluted, and the exhaust gas temperature will increase by more than ten degrees. Blowing the heating surfa...

AI Technical Summary

Problems solved by technology

This method has various problems such as blindness: on the one hand, overblowing will cause damage to the heating surface due to thermal stress and wear, shortening the life of the heating surface

On the other hand, insufficient soot blowing will cause the exhaust gas temperature of the boiler to rise, which will affect the economy of operation. Severe slagging on some heating surfaces will even cause boiler slagging accidents, which seriously threatens the safety of boiler operation.

[0004] Since the existing soot blowing optimization system is still in the guidance stage of open-loop operation, it has the following disadvantages: they cannot perform real-time online coal quality analysis and calculation, and to a certain extent, there is deviation in the monitoring of the pollution status of the heating surface

In addition, the existing system often only monitors the ash state of the heated area through a certain parameter, such as cleaning factor, without comprehensive consideration of various factors affecting soot blowing

At the same time, due to the limitation of on-site operating conditions, the optimization effect of the open-loop system cannot be guaranteed

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