On-line monitoring system and method for accumulated dust of convection heat exchanger at tail part of coal-fired boiler

Abstract

The invention discloses an on-line monitoring system and method for accumulated dust of a convection heat exchanger at the tail part of a coal-fired boiler. The system comprises a DCS (distributed control system) server, a serial server, a PLC (programmable logic controller) and an industrial personal computer, wherein a virtual DPU (distributed processing unit) program running on the DCS server is in TCP / IP (transmission control protocol / Internet protocol) communication with the serial server through a dynamic link communication interface program; the other end of the serial server is in communication connection with the accumulated dust monitoring PLC through an MODBUS; the PLC comprises a power module, a communication module and a processor module; the communication module is connectedwith a serial server and performs data communication through an MODBUS protocol; the processor module is connected with an industrial personal computer through a network cable to realize data communication; the power module is used for supplying power to the PLC; the industrial personal computer is used for debugging the dust deposition monitoring program and storing data; and the processor moduleis used for calculating the dust deposition degree of the convection heat exchanger at the tail part of the boiler in real time. The system is capable of characterizing the degree of dust depositionof the heat exchanger by monitoring the strength of the heat transfer process of the convection heat exchanger at the tail of the boiler in real time.

Description

technical field [0001] The invention relates to the technical field of coal-fired power plant boiler operation monitoring and optimization, in particular to an on-line monitoring system and monitoring method for ash accumulation in a convection heat exchanger at the tail of a coal-fired boiler. Background technique [0002] Power plant boilers that use non-design coal or thermal coal of poor quality can easily lead to serious ash accumulation and slagging in boiler heat exchangers. Especially, units that use Xinjiang Zhundong coal face serious ash deposition problems during operation. The dust deposited on the heat exchanger will hinder the heat transfer from the flue gas side to the working medium side, resulting in an increase in the exhaust gas temperature of the boiler and a reduction in boiler efficiency. The thicker dust will also form a flue gas corridor, which not only aggravates the local wear of the heat exchanger, but also causes the deviation of the steam tempera...

AI Technical Summary

Problems solved by technology

[0005] The internal working conditions of the operating boiler are harsh, and hardware equipment such as heat flow meters and high-temperature imagers are used to monitor the degree of dust in the heat exchanger. Not only the investment cost of hardware installation is high, but also the later maintenance costs are large, and equipment failures cannot be repaired during the operation of the boiler.

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