Material returning control system and method of circulating fluidized bed boiler

Abstract

According to the material returning control system and method of the circulating fluidized bed boiler, an air volume sensor and an air pressure sensor are arranged at an air inlet of a material returning system, a current sensor is arranged at a bus outlet of a material returning fan motor, and real-time monitoring data of the air volume sensor, the air pressure sensor and the current sensor are uploaded to an automatic control system of the boiler material returning system; real-time data of the sensor is compared with safety data set by the system, and the real-time working state of the material returning fan is monitored in real time. If the material returning fan is in the abnormal working state, different processing schemes for the faults of the material returning fan are given according to the critical degree of the faults of the abnormal working condition, furnace shutdown or equipment first-aid repair is avoided as much as possible, and compared with conventional emergency furnace shutdown or banking fire processing measures, the method can effectively reduce the number of non-shutdown times of a unit caused by the faults of the material returning fan, and improves the working efficiency of the unit. And the operation and maintenance cost of the unit is reduced to a certain extent.

Description

technical field [0001] The invention relates to the technical field of application of pumps and fans in the power generation industry, in particular to a material return control system and method for a circulating fluidized bed boiler. Background technique [0002] As we all know, circulating fluidized bed boiler technology is a new type of clean combustion technology, because it can burn some inferior fuels compared with traditional boiler technology, and at the same time it can realize desulfurization technology in the furnace, which effectively reduces the operating costs of enterprises and air such as sulfur dioxide. The discharge of pollutants is favored for its good economic and environmental benefits. The combustion principle of this type of boiler is that the materials in the combustion chamber are violently disturbed under the action of a certain fluidization wind speed, and part of the solid particles leave the combustion chamber and enter the furnace under the hig...

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Problems solved by technology

However, in the actual operation process, due to the violent fluctuation of the amount of returned material, the violent fluctuation of coal quality, the overload of the primary and secondary air volume motors, the overheating of the fan, abnormal noise, and excessive vibration, the return fan often fails suddenly during operation. Shutdown, resulting in serious ash blockage of the feeder, unable to adjust the differential pressure of the material layer in time, resulting in coking of the boiler, which seriously threatens the safety of the boiler operation

[0004] Moreover, because the return fan does not undertake the role of intensified combustion, in order to reduce the initial initial investment and operation and maintenance costs of some small and medium-sized circulating fluidized bed boiler power plants, many of the auxiliary equipment such as the return fan have adopted a stand-alone operation scheme; although In order to avoid the non-stop of the unit due to the failure of the return fan, all power plants strictly implement the regular inspection and equipment maintenance plan, and have a relatively complete emergency plan. However, due to the many auxiliary systems of circulating fluidized bed boilers, there are many adjustment and monitoring parameters, and the operating conditions are complicated. , so it is not uncommon for the boiler MFT to be caused by the failure of the single-unit operation of the return fan, resulting in non-stop accidents of the unit.

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